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The Burns Bog Lagg Zone : An Assessment of Hydrological and Biological Indicators in the Bog Avenant, Hannah; Canonizado, Cyra; Jacobson, Robert; Matsuo, Kevin Apr 26, 2017

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                       The Burns Bog Lagg Zone: An Assessment of Hydrological and Biological Indicators in the Bog   Hannah Avenant Cyra Canonizado Robert Jacobson Kevin Matsuo  26/04/17 ENVR 400 Sara Harris                                ABSTRACT   In the Delta Nature Reserve (DNR), there have been observed changes in the hydrology              and ecology. The intention of this community project in the DNR was to examine hydrological               and biological indicators within the lagg zone in order to begin the establishment of a monitoring                and restoration framework for the Burns Bog Conservation Society (BBCS) to pursue with the              Corporation of Delta. Groundwater depth, pH, and electrical conductivity were assessed           throughout the area to test whether these values fell within regularly observed ranges for a lagg                zone. ​Along with hydrology, percent cover of understorey species was studied to quantify the              effects that trampling by humans and dogs may have on the ecosystem. Finally, a literature               review was completed to determine potential methods of invasive species removal within the             DNR to find viable options for the BBCS. ​Spatial patterns in groundwater depth and pH               suggested heavy mineral water input from flooding by the stream in the northeast, but additional               dipwells should be installed near it to make clearer conclusions. Through percent cover             measurements near the boardwalk, it was determined that signage should be placed to dissuade              patrons of the DNR from stepping off the boardwalk. Mowing or hand-pulling for policeman’s              helmet and mowing and mulching in combination for reed canary grass are the most feasible               management methods. ​A long-term monitoring plan should be implemented to assess           hydrological and ecological parameters, with measurements at least monthly to account for            seasonal variation while still maintaining feasible monitoring intervals for the BBCS.  AUTHOR BIOS   Hannah Avenant ​is a 4th year Environmental Sciences student at UBC, with a concentration of Ecology                and Conservation. In the summer of 2016, she worked as a Research Assistant for Agriculture and                Agri-food Canada in the Insect Pest Lab. Her interests include plant biology and marine conservation.   Cyra Canonizado ​is a 4th year Environmental Sciences student at the University of British Columbia,               concentrating on Land, Air and Water. She has knowledge in a variety of areas including oceanography,                soil science, hydrology, and environmental chemistry. Her technical skills include chemical analysis using             analytical chemistry methods and data analysis through Excel and Matlab.   Robert Jacobson is a 4th-year Environmental Sciences student at the University of British Columbia,              with a focus on ecology and conservation. An outdoor enthusiast, he plans to pursue further studies and                 work in the field of ecological restoration after graduating from UBC.  Kevin Matsuo is a 4th year Environmental Sciences student at the University of British Columbia,               concentrating on Land, Air and Water. He has experience in chemical and ecological lab and field work                 including relevant analytical methods from selected UBC courses.   1   TABLE OF CONTENTS   Abstract  1 Author Bios   1 Introduction   4 Methodology 7 Hydrology 7 Trampling 9 Literature Review 10 Results 11 Hydrology 11 Trampling 16 Literature Review 20 Discussion 22 Conclusions   28 Acknowledgements   29 Literature Cited   30 Appendices  34 Appendix 1. Dipwell coordinates                                                                               34 Appendix 2. Mean values for hydrological parameters 35 Appendix 3. ​Locations of trampling transects  35 Appendix 4. Raw values for species percent cover (W)                                            36 Appendix 5. Raw values for species percent cover (E) 37 Appendix 6. Simpson’s diversity index calculations 38 Appendix 7. Restoration and Invasive Species Removal Literature Review 39  List of Tables Table 1. Literature review synopsis of methodology for removal of reed canary 11 grass and policeman’s helmet in the DNR​.  Table 2. Results of a Welch’s ANOVA for each of the three water parameters. 15 Table 3. ​Invasive species removal literature review results for reed canary 21 grass and policeman’s helmet. Table 4. Summary of monthly mean depth to water table values (Owen, 2015). 22 Table 5. ​ ​Summary of mean depth to water table, pH and electrical conductivity 24 (Howie, 2012; Howie, 2013).     2   List of Figures  Figure 1.​ ​Diagram of a raised peat bog 4  Figure 2. Sampling locations of transects (yellow), control transects (blue), and 7  dipwells Figure 3. Diagram detailing calculation of depth to water table 8 Figure 4. Diagr​am of 1 m​2​ quadrats placed at different distances from the 9 boardwalk. Figure 5. Average depth to water table from the surface of the ground in the 12 Delta Nature Reserve. Figure 6. Average electrical conductivity of groundwater in Delta 13 Nature Reserve. Figure 7. Average pH of groundwater in Delta Nature Reserve. 13 Figure 8. Mean depth to water table values. 14 Figure 9. Mean pH values. 14 Figure 10. Mean electrical conductivity values. 15 Figure 11. Scatterplot of mean pH vs mean electrical conductivity for all dipwells 16 Figure 12. Species composition at 8 meters from the boardwalk of the 3 17 control groups, representing the 3 distinct ecosystems. Figure 13. Average percentage cover with increasing distance from boardwalk 18 in the three distinct ecosystems. Figure 14. Simpson’s diversity indices of different distances from boardwalk 19 of the three ecosystem in the three distinct ecosystems. Figure 15. Map of DNR showing dipwells and Howie’s (2012) transects. 23 Figure 16. Reed canary grass. 43 Figure 17. Policeman’s helmet. 45               3   INTRODUCTION   Burns Bog, due to its hydrological, biological, and topographical features, is classified as             a raised peat bog - the largest of its kind in western North America. The features Burns Bog                  displays include an internal water mound, nutrient-poor and acidic water sourced from            precipitation, a two-layered composition, and peat-forming biological communities (Howie ​et          al., 2011). The two layers are the acrotelm, which is the living layer that includes ​Sphagnum                mosses, and the catotelm, which is the dense peat that permanently resides underneath (Figure              1). The Burns Bog lagg zone covers most of the Delta Nature Reserve, and can be divided based                  on two plant communities: the ​Spiraea thicket lagg and Peaty forest lagg (Howie and van               Meerveld, 2016). The lagg zone acts as a buffer between the higher nutrient waters surrounding               the bog and the nutrient-poor waters within. This buffering system is crucial in maintaining the               unique biological communities within the bog, such as ​Sphagnum ​moss mounds. Along with             water chemistry, a high water table is critical to peat communities. Therefore, inflows of water               from precipitation must meet water amounts lost to evaporation, transpiration, and runoff to             maintain the communities (Howie ​et al., ​2009).   Figure 1. ​Diagram of a raised peat bog, as is Burns Bog in Delta, BC. Image retrieved from                  http://www.worldhistory.biz/sundries/43816-bogs-and-drainage.html.   Over the span of the UBC Environmental Sciences community project with the Burns             Bog Conservation Society (BBCS), one focus was to begin monitoring the water table height,              pH, and electrical conductivity of the groundwater within the Delta Nature Reserve. It had been               observed that areas of the Delta Nature Reserve were drying out, and that salal was taking over                 areas previously inhabited by ​Sphagnum ​moss, an important bog species. Along with these two              issues, high abundances of invasive species reed canary grass and policeman’s helmet were             observed along the periphery of the reserve. This project was completed to set a framework for                4   the continued monitoring of the hydrology in the lagg zone of Burns Bog, as well as provide                 methods of invasive species removal for the BBCS. The pH and electrical conductivity are useful               indicators for monitoring the ecological succession of the lagg zone in response to recovery              efforts (Gorham ​et al., ​2003). There are several restoration strategies that focus on restoring the               water table, including blocking ditches, bunds and terracing, and using mulch (Howie ​et al.,              2011). It is our hope that this foundation of data, along with a proposed plan for monitoring in                  the years to come, can be used to help educate others and preserve the Delta Nature Reserve.  Burns Bog is an ombrotrophic bog, therefore rain is its main source of water. However,               years of urban and industrial development adjacent to the bog raise the possibility of              contamination by external water sources, such as runoff. These external sources can significantly             influence the mineral composition and water chemistry of the lagg zone (Howie ​et al.​, 2009).               The Burns Bog Conservation Society has raised concerns over changes that they have been              noticing over the years, including the concern that some areas have become noticeably drier,              Sphagnum ​moss is disappearing, and other species such as salal have begun to outcompete              Sphagnum​,  as mentioned above. To address these concerns, we ask the following questions:   ● How do the pH and electrical conductivity of the groundwater, as well as the depth to water table vary throughout the Delta Nature Reserve?   ● Through spatial analysis of the hydrological factors pH, electrical conductivity, and groundwater level, how do potential outside water sources affect hydrological parameters of the Delta Nature Reserve?  ● To what extent does trampling with increasing distance from the boardwalk affect change in species composition and vegetation percent cover in the Delta Nature Reserve?  ● What are some feasible invasive species removal methods that can be applied by the Corporation of Delta in the Delta Nature Reserve?  By pursuing the first two questions, we can observe spatial distributions to determine if              any patterns in hydrology could be the reason for the problems at hand. If we observe any                 deviations from expected patterns found in previous studies, we can explore the possibility of              hydrology being altered by outside sources. Knowledge of the spatial distributions can help             identify any problem areas that will need to be dealt with. Since hydrology plays a key role in                  maintaining the stability of the lagg zone’s ecosystem (Howie ​et al.​, 2009), regular monitoring of               hydrology is essential to proper maintenance of the Delta Nature Reserve. Given that hydrology              data in the Delta Nature Reserve is very fragmented, this project will mainly serve as baseline                5   research for collecting hydrologic data that can be used in future monitoring and maintenance              procedures.   In addition to the hydrology, human activity has the potential to alter the biology of the                bog. ​The Burns Bog Conservation Society has also expressed concern about the disappearance of              Sphagnum cover adjacent to the boardwalk. ​Sphagnum ​moss is a highly influential bog species,              and is often referred to as the building block of the bog. Trampling, as a result of individuals                  stepping off of the boardwalk, is a strong possibility for the disappearance of ​Sphagnum ​moss;               this possibility will be explored with the third research question. Sources of trampling damage              can be from humans and/ or dogs venturing off the boardwalk into deeper and more sensitive                areas of the Delta Nature Reserve. These mechanical disturbances can change the properties of              soil components, but more importantly cause a detrimental reduction in plant cover as well as               species composition of the plant community, increasing the risk of establishment of invasive             species. Low-intensity trampling causes noticeable damage, while high-intensity trampling can          reduce the ​Sphagnum cover into a layer of muck with no vegetation. Some studies show that                Sphagnum ​cover can recover as quickly as after two years from ceasing the trampling              disturbance. (Arnesen, 1999; Robroek ​et al​., 2010).  The fourth research question in this report is the potential restoration of the Delta Nature               Reserve, as well as the removal of invasive species along the stream banks on the periphery of                 the Reserve. In order to create the foundation of knowledge necessary to derive a restoration plan                for the Delta Nature Reserve, a literature review was completed. The first item of concern within                the Delta Nature Reserve is hydrological, as mentioned previously; it has been observed by              members of the BBCS that parts of the ecosystem are drier than historically observed. This is                problematic for many of the bog species that require an abundance of water to survive, such as                 Sphagnum ​moss. In the literature review, a goal was to research methods of bog water table                restoration that have been previously utilized and pinpoint possible methods that could be             successful in the Delta Nature Reserve. Another goal was to discover ways to restore ​Sphagnum               community abundance in a bog environment.   The final part of the literature review aimed to address the matter of invasive species               removal within the Delta Nature Reserve, specifically on the banks of the stream that flows               there. The two main invasive species that have been observed are ​Phalaris arundinacae, ​or reed               canary grass, and Impatiens glandulifera, ​or policeman’s helmet. These two plant species display             all of the qualities of an invasive species that make them difficult to eradicate - effective                dispersal, fast reproduction, and quick growth rate. The process of complete removal of the two               invasive species from the Delta Nature Reserve must also aim to minimize damage to the               surrounding ecosystem. The literature review aimed to pinpoint both economically and           6   ecologically feasible removal strategies of reed canary grass and policeman’s helmet from the             Delta Nature Reserve.   METHODS  Hydrology   Data Collection   Depth to water table, pH, and electrical conductivity were collected from eight            pre-existing dipwells located throughout the Delta Nature Reserve (Figure 2). Seven were            located using coordinates from Owen (2015), and one additional dipwell was found, which we              identified as “Unmarked” (DW um). The dipwell marked “4” in Owen’s study was inaccessible,              and the one she marked as “V” could not be located due to snow. The dipwell marked “I” did not                    have a lid, so we covered the opening with duct tape.    Figure 2. ​Sampling locations of transects (yellow), control transects (blue), and dipwells (pink) in the               Delta Nature Reserve. 7    Figure 3. Diagram detailing calculation of depth to water table. Labels are shown for depth from top of                  dipwell (to the water table) and pipe-stickup. The blue line indicates the water table  As suggested by Howie (2012), one week prior to collecting the first samples, a              peristaltic pump (Pegasus​® Athena) was used for 30 minutes at 300mL/min to remove stagnant              water in each dipwell, allowing them to be refreshed with groundwater. We took measurements a               total of four times (January 14th, January 29th, February 11th, and March 5th, 2017), visiting the                dipwells in the same order each time. To calculate the depth to water table from the surface, the                  pipe stick-up (height of each dipwell opening above the ground) was subtracted from the depth               to the water table from the rim of the dipwell (Figure 3), as measured by an electric water level                   probe (Solinst​® Model 101 Water Level Meter). ​pH and electrical conductivity were measured by              directly inserting the probes into the dipwells ​(​Oakton​® pH 11/110 Handheld Meter; Oakton​®             Con 6 Handheld Meter). Coordinates for each dipwell were recorded from the compass app on               an iPhone 6. After measurements were collected, each dipwell was pumped out for 20 minutes at                300mL/min..   Data Analysis   The mean values for each of the three parameters at each of the dipwells were mapped                using ArcGIS 10.5. The data were loaded as XY data, converted to a point shapefile, and then a                  raster for each was interpolated using bilinear interpolation. To determine if the measurements             taken at each dipwell formed a statistically significant spatial pattern, R (version 3.3.2) was used               to conduct a Welch’s ANOVA was for each of the three parameters, as the minimum and                maximum variance among the groups for each parameter differed by more than a factor of four.       8   Trampling  Data Collection     Figure 4​. Diagram of 1m​2​ quadrats placed at different distances from the boardwalk.   To examine the possibility of the decrease in ​Sphagnum ​cover from trampling, 10             transects perpendicular to the trail 5-20 m apart were randomly allocated using MS Excel (Figure               2). 1 m x 1 m quadrats were used to create three plots along each transect. To enable sampling of                    10 transects in the 3 distinctly different ecosystems of salal-rich, “bog”, and peat forest, transects               were randomized to be placed in any ecosystem. The quadrats were placed along the transect at                0, 1.5, and 5 m away from the boardwalk ​(Figure 4). Three Control plots were each randomly                 placed 8 m away from the boardwalk in each ecosystem, with the assumption of no history of                 trampling. 8 m was selected for the control because accessibility at this distance is very low.                Control 1 represents the salal-rich region, Control 2 is “bog” and Control 3 is peat forest. This                 led to a total of 30 plots, and three control plots. The distances between each plot were chosen to                   be used as a proxy for three trampling intensities (low, medium and high), with the assumption                that trampling intensity will be higher adjacent to the boardwalk and lower at farther distances.               The dominant species in each control (largest relative cover) were chosen as a representative              species for trampling, this allowed a more consistent comparison between each ecosystem.            species Percentage cover of different species were recorded and the species composition at the              different quadrats were graphed. In addition, the relative cover of species were also calculated              by:  9   To determine the impact of trampling on species diversity, the Simpson’s diversity index             (D) was estimated using the following equation:   where ​n is the percent cover for species ​i. ​S is the number of species and ​N is total number of                     plants in the population. For this calculation, the distances at different transects in each              ecosystem were grouped. This resulted to 4 diversity indices of each distance (including the              control) for the 3 ecosystems.  Data Analysis   The standard error of the mean was calculated to estimate variability of the average              percentage cover with increasing distance from boardwalk. Standard error bars that overlap            between distances show no significant difference.    Invasive Species Removal Literature Review  To complete this literature review, peer-reviewed papers were compiled and read through            in order to locate scientific research projects that assessed removal methods. Along with             peer-reviewed papers, articles from cities that faced similar issues with the invasive species were              read, as these articles often had valuable information about the use of different methods in a                non-scientific context. Once these methods had been compiled, they were evaluated in the             context of the Delta Nature Reserve to conclude if each method was a viable one for the area                  (Table 1). Findings were compiled into a literature review format; twenty sources in total were               utilized to form practical removal methods for the two invasive species. Success of removal of               invasive species is particular to size of stand and location.            10   Table 1. ​Literature review synopsis of methodology for removal of reed canary grass and policeman’s helmet in the DNR.  Reed Canary Grass Removal Method Viable for DNR Hand-pulling ✓ Shading/Mulching ✓ Mowing ✓ Plowing ✗ Fire ✗ Herbicides ✗ Policeman’s Helmet Removal Method Viable for DNR Hand-pulling ✓ Mowing ✓ Herbicides ✗   RESULTS   Hydrology   Spatial analyses revealed three different patterns for the measured water parameters. The            water table was closest to the surface on the northeast side of the Delta Nature Reserve (Figure                 5). The electrical conductivity was highest in the southern area of the Delta Nature Reserve               (Figure 6), while pH showed an opposite pattern to that of the water table depth (Figure 7), being                  lowest in the south-east corner.    A Welch’s ANOVA (Table 2) revealed that depth to water table, pH, and electrical              conductivity all varied significantly between dipwells (P=0.0072, 0.034, 0.00024 respectively).          For depth to water table, the dipwells in the north-west did not differ from any of the other                  dipwells, but several of the other dipwells differed from one another, though spatial groupings              cannot be made (Figure 8). Dipwell I differed from dipwells in the north-west corner and some                11   of the other western dipwells, having a much higher electrical conductivity (Figure 9). Dipwell I               also had a lower pH on average than most of the other dipwells, which usually did not differ                  from one another (Figure 10).   Figure 5. Average depth to water table from the surface of the ground. Lower depths (in green) are                  considered better values for the persistence of a bog. Measurements were taken in the Delta Nature                Reserve biweekly from January to March 2017.  12    Figure 6. ​Average electrical conductivity of groundwater in Delta Nature Reserve. Higher EC values (in               green) are usually better for a bog, as pH values further from 7 lead to more dissolved ions and thus                    higher electrical conductivity. Measurements were taken biweekly from January to March 2017.  Figure 7. Average pH taken at dipwells throughout the Delta Nature Reserve biweekly from January to                March 2017. Lower pH values (in green) are closer to standard bog values. 13     Figure 8. ​Mean depth to water table at various dipwells spread throughout the Delta Nature Reserve. N=4 for each group (except Unmarked, for which N=3). Error bars indicate standard error.   Figure 9. ​Mean pH values at various dipwells spread throughout the Delta Nature Reserve. N=3 for each                 group. Error bars indicate standard error. 14    Figure 10​. ​Mean electrical conductivity at various dipwells spread throughout the Delta Nature Reserve.              N=4 for each group. Error bars indicate standard error.   Table 2. Results of a Welch’s ANOVA for each of the three water parameters. There were 8 groups for                   each analysis. N=4 for depth (except for one group, which had N=3) and EC, and N=3 for pH. Parameter Numerator df Denominator df F-Value P-Value Water Table Depth 7 9.78 14.67 <0.01 pH 7 6.67 4.61 0.03 Electrical Conductivity 7 9.18 15.00 <0.01   15    Figure 11. Mean pH vs mean electrical conductivity for all dipwells in the DNR. Ranges for different                 water types that were identified by Balfour and Banack (2000) and described in Howie and van Meerveld                 (2011) are indicated by double headed arrows: bog water (pH 3.5-5.5), transitional water (pH 4.5-6.0),               and minerotrophic water (pH 5.0-8.0).  Figure 11 plots mean pH against mean electrical conductivity. Ranges for different water             types (Balfour and Banack, 2000; Howie and van Meerveld, 2011) were indicated to provide a               sense of where data points lie. Mean electrical conductivity values fell between 65 and 165               μS/cm, while mean pH recordings collected fell between 3.5 and 4.5, and are classified as “bog                water” by Balfour and Banack (2000). No apparent correlation between pH and electrical             conductivity was found.  Trampling  Selected species of each distinct ecosystem (Figure 13) show a weak pattern of increasing              average percentage cover with distance from boardwalk. There is no statistical difference            between the different distances from the boardwalk as suggested by standard error. However,             there is a significant difference between the three distances from the boardwalk and their              respective control (Figure 13). Similarly, there is also no statistical difference between distances             from boardwalk for Simpson’s Diversity index (Figure 14). A Simpson’s Diversity Index of 1              suggest no diversity.   16    Figure 12. ​Species composition at 8 meters from the boardwalk of the 3 control groups, representing the                 3 distinct ecosystems.    a 17   b  c  Figure 13. ​Average percentage cover with increasing distance from boardwalk in the three distinct              ecosystems: a) Salal - Salal-rich b) Labrador Tea - “Bog” c) Sphagnum - Peat Forest. Error bars represent                  standard error of the mean (N=3). Dotted line represents the value seen 8 m away from the boardwalk.                  Species representative of each ecosystem were chosen based on the dominant species in each control.  18    a  b 19    c Figure 14. Simpson’s Diversity indices of different distances from boardwalk of the three ecosystem in               the three distinct ecosystems: a) Salal - Salal-rich b) Labrador Tea - “Bog” c) Sphagnum - Peat Forest.                  Error bars represent standard error of the mean (N=3). Dotted line represents the value seen 8 m away                  from the boardwalk.    Invasive Species Removal Literature Review   Removal methods viable for the DNR were compiled into a table (Table 3), and listed               with their various benefits and drawbacks.                 20   Table 3. ​Invasive species removal literature review results for reed canary grass and policeman’s helmet. Reed Canary Grass Removal Method Pros Cons Hand-pulling Small infestations – ensures removal of whole plant when completed in spring-early summer Unrealistic with large infestations, can spread seeds if done when plant seeds mature Shading/Mulching Prevents vegetative regrowth of RCG Non-selective, kills native species present as well Mowing If done when seeds not mature, removes bulk of plant - stubs can be mulched to prevent regrowth If done when seeds mature, will spread seeds. Stubs will regrow if not dealt with Plowing Suitable for when native species present to recolonize Can release seedbank, further spread invasive species growth Fire Can be used before herbicide treatment to lessen vegetation cover Not useful on its own; can release seedbank Herbicides Will effectively prevent regrowth from seeds and rhizomes Can harm stream ecosystem if proper surfactant not used Policeman’s Helmet Removal Method Pros Cons Hand-pulling Small infestations. Should be done in spring before seeds develop Regrowth can occur if plant parts not disposed of properly (bagged and removed from site) Mowing Good for larger infestations – cut below lowest node to prevent regrowth Seeds can get into stream and spread – place barriers along stream while mowing to prevent this Herbicides Can be used to spot-treat regrowth after mowing or hand-pulling Can harm stream ecosystem if proper surfactant not used           21   DISCUSSION   Hydrology  Comparisons with past studies  In order to assess how characteristic our results were of the DNR and whether any               changes have occurred, we compared our data to other similar studies conducted in the past.               Owen (2015) also carried out a hydrology study, with measurements collected weekly, at the              Delta Nature Reserve between August 2013 and February 2014. While they did measure from              the same dipwells used in our study, their data was spatially averaged across all the dipwells to                 get one mean depth to water table value for the entire DNR. They observed mean depth to water                  table values (Table 4) across the whole DNR of 8.5 cm in January 2014, and 13.7 cm in February                   2014. These high water table values were due in part to heavy rains, particularly on the week of                  January 17th and February 14th. In comparison, we measured depth to water values of 19 cm in                 January 2017 and 15.1 cm in February 2017. During these periods, we experienced heavy              snowfall rather than rain, which could explain the differences between values in 2014 and 2017               for the same months. From this alone, it is hard to conclude whether the water table values we                  obtained are “characteristic” of the DNR or whether significant changes occurred simply because             of the different weather conditions and their influence on the groundwater. Furthermore, our             study completely excludes summer months that could be compared with Owen (2015)’s data,             wherein summer months show a drastic increase in the depth to water table (signifying a deeper                water table), with a mean value of 49.5 cm for August 2013.  Table 4. ​Summary of monthly mean depth to water table values from August 2013 to February 2014, as                  reported in a 2015 report on the Hydrology of the DNR (Owen, 2015).  Paper Month Mean Depth to Water Table (cm) Owen (2015) August 2013 49.5 September 2013 48.2 October 2013 22.4 November 2013 17.6 December 2013 15.8 January 2014 8.5 February 2014 13.7 22     Figure 15. ​Map of the Delta Nature Reserve with pink markers indicating numbered dipwells and white                markers indicating locations of transects sampled by Howie (2012).  Howie (2012) observed three study transects (Figure 15) to the east of Highway 91 in the                 Delta Nature Reserve labelled as Lagg 1 (​Spiraea thicket lagg), Lagg 2 (Peaty forest lagg), and                Mineral (area beside the railway). They recorded values for depth to water table, pH and               electrical conductivity (Table 5). Since their transects do not directly correspond to any of the               dipwell locations that we sampled from, we can only compare values from the closest possible               dipwell to the transect in question.  The Lagg 2 (Peaty forest) area corresponds to the area about 100 m north-east of DW I                 and 100 m north-west of DW II. Values at this transect were measured to be less than 10 cm for                    the sampling period of January 2011 to March 2011. On the other hand, our values at DW I                  ranged from 22.3 cm to 36 cm from the surface, while our values at DW II ranged from 8.1 cm                    to 17. cm from the surface. If values at Lagg 2 are taken as a proxy for DW I and DW II, 2017                       values suggest that the water table at DW I is lower than the past, while DW II does not seem to                     differ much from the past measurements.  23   The Lagg 1 (​Spiraea ​thicket) area corresponds to the area about 74 m southwest of where                DW 6 is installed. Here, they measured depth to water table values between 20 cm and 30 cm for                   the sampling period of January 2011 to March 2011. In comparison, our values at DW 6 ranged                 from about 16.5 cm to 23 cm below the ground surface. Taking Lagg 1 values as a proxy for DW                    6 values, comparisons with Howie (2012) seem to indicate that the water level is now higher                than before.  Table 5. ​Summary of mean depth to water table, pH and electrical conductivity values at the                DNR, as reported in an unpublished report (Howie, 2012) and a Ph.D Thesis (Howie, 2013).  Paper Area Mean Depth to Water Table (cm) Mean pH Mean EC Howie (2012) Bog 0-32 4.09-4.36 101-122 Lagg 1 -14-58 4.17-4.57 66-81 Lagg 2 13-57 5.20-5.39 78-165 Mineral -17-48 5.51-5.72 106-168 Howie (2013) Spiraea Thicket -14-58 Winter:​ 4.49 Winter: ​68   Summer:​ 4.35 Summer: ​66 Peaty Forest 13-57 Winter:​ 5.39 Winter:​ 105   Summer:​ 5.34 Summer:​ 165   Howie (2012) measured pH and electrical conductivity every 2 months at the Delta             Nature Reserve from September 2010 to December 2011. Average winter pH values were 4.49 at               Lagg 1, and 5.35 at Lagg 2. Our values at similar sites were 4.27 (DW 6), 3.71 (DW I), and 4.16                     (DW II), respectively. Average winter electrical conductivity values were 68 μS/cm at Lagg 1              and 105 μS/cm at Lagg 2. In comparison, our electrical conductivity values were 88.65 μS/cm               (DW 6), 164.4 μS/cm (DW I), and 117.82 μS/cm (DW II). Comparisons with Howie (2012)’s               data show that while their pH leans more towards a characteristically minerotrophic water pH              (Howie and Meerveld 2011), our pH values were noticeably more acidic and “bog-like” (Figure              11), especially at DW I. Similarly, our electrical conductivity values were also noticeably             different, especially in comparing the Lagg 1 value to DW6 and the Lagg 2 to DW I.  While it seems that changes have occurred from 2011 to 2017, it is difficult to say                whether these differences point towards an underlying problem as there are many factors that              24   could explain why the values seem to significantly differ. Values may simply differ because the               distances between the comparison points are far enough that groundwater characteristics differ as             well. Additionally, the weather conditions during Howie (2012)’s study are unknown, and if             these were to differ significantly from the weather conditions during our study, this could also               explain the differences in values obtained.   Spatial Distributions   From Figure 5, we can observe a general trend of increasing depth to water table from the                 northeastern part of the DNR towards the southwestern part, where the main bog is cut off by                 Highway 91. This is a similar pattern to Howie (2012)’s study, where they described a higher                depth to water table in the Peaty forest lagg and lower depth to water table at the ​Spiraea ​thicket                   area to the west. It is possible that these areas of high depth to water table are due to a denser                     cover of trees (Howie, 2009). Tree height is said to be related to water table, wherein one would                  find taller trees in areas with a higher measured depth to water table (Howie, 2009). Lower depth                 to water table values at the northern part of the DNR could be due to flooding of the creek                   leading to increased water levels at adjacent dipwells. Howie (2012) also mentions a higher              depth to water table in the “Mineral area” (Figure 15; an area of higher soil mineral content                 adjacent to the railway), however, we were unable to measure here due to dipwells not being                installed in this area of interest.   From Figure 6, we observe increasing electrical conductivity values towards the southern            part of the DNR. This figure suggests that electrical conductivity increases with decreasing pH              values. However, the expected pattern should be a decrease in electrical conductivity towards the              bog, as water farther away from the stream should have less minerotrophic influence and              therefore a lower concentration of dissolved solutes (Howie, 2013). Despite this, Howie (2013)             also mentions that when pH values are lower than 5.0, electrical conductivity values can be               significantly affected by conductance due to hydrogen ions. Naturally, lower pH values translate             to higher amounts of hydrogen ions in solution. However, this correction led to some of our                values becoming negative, so we could not use these values. This led to questions regarding the                validity of our measured pH values.   From Figure 7, the general trend in pH values is a decrease from the northeastern DNR to                 the southwestern region. This pattern is to be expected as the northeastern part is adjacent to an                 urbanized area, as well as an active railway, which are both potential sources of minerotrophic               runoff (Howie, 2013). As the creek adjacent to the railway floods during heavy rain periods, this                could increase mineral content further into the lagg zone, causing higher pH values in the areas                most affected. Neighbouring industrial areas can also be a source of mineral deposition as dust               precipitates over areas at the margin of the DNR (Howie, 2013). On the other hand, the                25   southwestern region is further from such external influences, thus explaining the pH values             leaning towards characteristically acidic soil water values of an undisturbed bog.  Sources of Error and Limitations   Possible sources of error include weather effects and instrumental error. Sampling was            carried out during a period of heavy snow and some flooding, which is uncharacteristic of               Vancouver and may have affected our measurements. During heavy periods of rain, some             malfunctioning would occur with the pH readings, which led to values being extremely             underestimated. This occurred during our January 29th sampling day, where there was severe             rainfall, leading us to completely exclude any pH values collected. While precipitation was             lighter on other sampling days, it is still possible that this same underestimation effect may have                affected our readings to some degree. But judging from the similarity of our data with that of the                  aforementioned studies, this underestimation effect may not have been too significant.           Additionally, the electrical conductivity probe would sometimes display unusually high values           under these conditions, however, this was mostly corrected by recalibrating the instrument in the              field.  Patterns observed during this study may possibly be restricted to the wet season, due to               flooding of the stream being mainly due to heavy rains. The main input of water into the DNR                  comes from precipitation (Hebda, 2000). While winter months like our sampling period ​are             characterized by wet conditions, the DNR has been shown to experience a moisture deficit              during the summer months (Hebda, 2000). Evapotranspiration, the primary water removal           process (Hebda, 2000), is relatively low in the winter as vegetation are in their dormant phase                (Oishi ​et al​.​, 2010). However, in the summer, evapotranspiration is at its peak as vegetation is at                 the height of photosynthetic activity (Iroumé et al​., 2005). Therefore, summer months should             also be investigated to examine whether there is a change in spatial distribution and mean values                of parameters compared to the wet season.  Trampling   Figure 13 displays average percentage cover of each control in the three distinct             ecosystems. The average percentage cover of the selected species for each ecosystem showed no              significant difference between distances from the boardwalk. However, percentage cover of           dominant species at the different distances for each ecosystem are significantly less than its              control. Therefore, it can be concluded that trampling is apparent but the extent to which species                composition is affected with increasing distance within 5 meters is insignificant.    26   The degree to which trampling affects each species varies. This may be due to the general                structure, branches and leaves of the plant species that affect the magnitude of response toward               trampling. For example, in the Bog ecosystem (Control 2), Labrador tea is the dominant species.               Figure 13b (Bog ecosystem) suggest almost no difference of percentage cover at different             distance with its control, thus relative cover also remaining constant. With its tall branches and               structure, it is difficult to step off the trail in this region, therefore may be subject to less                  trampling.    Simpson’s Diversity indices of the three ecosystems showed no observable pattern           (Figure 14) with increasing distance from boardwalk. The values at different distances of each              ecosystem varied randomly. However, they are significantly less than its control. This may             suggest that the extent to which trampling is occurring does not have a significant impact on                species diversity until 5 meters from the boardwalk. The three controls, display higher values of               Simpson’s Index therefore suggesting  lower species diversity.   A more effective approach for assessing the impact of trampling is isolating the effect of               the amount of trampling from other confounding variables. During the experiment a number of              observations were made. These include, noticing that many dogs were not on a leash and               ventured in areas away from the boardwalk. Therefore, for future studies a comparative analysis              of human and dog trampling can be conducted, to accurately determine the source of trampling.               In addition, the use of hiking sticks was observed, however, the extent to which it affects                vegetation is unknown. Other response variables to trampling can also be studied such as litter,               rock and soil abundance. Accurately determining the resistance and resilience of each species to              trampling pressure can determine areas which are most sensitive that may require more attention.              However, measurements may be needed to be conducted after one year to determine recovery of               vegetation. Including the use of aerial photography and computerised image analysis, can            accurately document and monitor changes of land cover resulting in better understanding of             cause and effect of species cover.   Invasive Species Removal Literature Review  With the issue of reed canary grass, the potential reasons why it infiltrated the              streambank in the first place should be addressed; the stressors that disturbed the ecosystem to               allow for reed canary grass to colonize should be removed if still at work. More ecologically                diverse sites respond to restoration efforts better, so if possible, the establishment of native              species should also be completed so that native species can take over areas where reed canary                grass has been removed. Hand-pulling is not a viable option for the removal of reed canary grass,                 as the abundance of the species is too high. Herbicide use is also not recommended due to the                  adjacency of the salmon-bearing creek. Mowing of invaded sites should be completed in spring              27   to early summer, before seeds have developed. After the grass has been mowed, stalks should be                covered in mulch or plastic to prevent regrowth. Continued monitoring and treatment would be              required for up to 5-10 years to ensure complete removal of reed canary grass (Tu, 2004). Along                 with long term monitoring, an adaptive management approach should be utilized in order to              effectively remove the species (Tu, 2004).  Policeman’s helmet is more easily removed through physical means such as hand-pulling,            though it must be ensured that all of the plant parts are removed and properly disposed of.                 Barriers should be placed along the stream as removal takes place to ensure that no seeds or plant                  matter enter the waterway, as seeds can persist in water for many months. As with reed canary                 grass, removal should be completed before seeds have fully developed, in spring or early              summer. Mowing can also be utilized for larger infestations, and is most successful when plants               are cut below their lowest nodes to prevent regeneration. As with reed canary grass, long-term               monitoring should be implemented in order to maintain complete eradication.  CONCLUSIONS   Hydrology   Overall, pH values were observed to be characteristically acidic, as expected in a bog or               lagg zone environment. The observed spatial distributions of the three water parameters may             indicate contamination from the stream during flooding periods, but more data will need to be               collected, especially during the summer months when flooding is not occurring, to make definite              conclusions. Additional dipwells will also need to be installed in the northeast corner of the Delta                Nature Reserve to better depict the spatial distribution of the different parameters. The measured              depth to water table data does not seem to reflect values that would suggest any issues. However,                 one should take into account that data was collected during an odd winter that included heavy                snowfall and very cold temperatures. Future measurements should be conducted at least once a              month, which accounts for seasonal variations while still being feasible for the BBCS as a               monitoring period. Annual data should also be compiled, with comparisons made between past             and subsequent years, in order to better assess long-term trends before deducing that a particular               deviation is indicative of an underlying problem.        28   Trampling   To our knowledge, this is the first study conducted in the Delta Nature Reserve that               demonstrates that trampling increases species diversity (lower Simpson’s Diversity-D than          control) and decreases relative cover of the selected species in each ecosystem. This emphasizes              the importance to consider mechanical disturbances from recreational activities in the bog.            Increasing the number of signs alerting visitors to stay on the boardwalk, leash their dogs and to                 be considerate of the vegetation around the area can possibility decrease the effects of trampling.               If needed, a monetary penalty may be enforced to increase the level of deterrence. In addition,                further information regarding the need to prevent trampling may be included areas along the              boardwalk.   Invasive Species Removal   Reed canary grass, which is found in high abundances along the stream in the Delta               Nature Reserve, has high seed counts and can reproduce both sexually and vegetatively through              rhizome growth; these factors make it extremely difficult to completely eradicate. If possible, the              establishment of native species should be done in synchrony with the removal of reed canary               grass to help prevent its continued monoculture on the stream banks. Since reed canary grass is                observed in such high quantities, mechanical removal such as hand-pulling is not feasible for the               Delta Nature Reserve. Mowing is a viable option, as long as mowed stalks are then shaded out                 with plastic or mulch in order to prevent vegetative growth. Long-term monitoring and removal              would be required to ensure the complete removal of the invasive species.   Policeman’s helmet can be removed in a more straightforward approach. The species is             more easily removed through physical means such as hand-pulling, though it must be ensured              that all of the plant parts are removed and properly disposed of. Barriers should be placed along                 the stream as removal takes place to ensure that no seeds or plant matter enter the waterway, as                  seeds can persist in water for many months. Mowing can also be done and is most successful                 when plants are cut below their lowest nodes to prevent regeneration. As with reed canary grass,                long-term monitoring should be implemented in order to maintain complete eradication.    ACKNOWLEDGEMENTS   Special thanks to our community partners, previously Evelyne Young and currently Hillary            Rowe of the Burns Bog Conservation Society, for making this project possible and guiding the               final product with your vision!   29   Another thank you to Laura Laurenzi and the UBC Hydrogeological Department for generously             showing us how to properly use hydrological equipment and lending it to us for the duration of                 our measurements.   Thirdly, we would like to thank Sarah Howie from the Corporation of Delta for helping us                narrow down the scope of our project and giving us many useful resources and tips.   We would also like to thank our fellow ENVR 400 classmates for support and helpful peer                review throughout the course of the project!   Lastly, but certainly not least, we would like to give a massive thanks to Sara Harris from the                  UBC EOAS department, as well as Bernardo and Vikas, for endless knowledge, guidance, and              help! Without you, we certainly would not have achieved what we did.    LITERATURE CITED   Apfelbaum, S. and C. Sams. 1987. Ecology and control of reed canary grass (​Phalaris arundinacea ​L.). Natural Areas Journal​ ​7: 69-75.   Bahm, M., T. Barnes, and K. Jensen. 2014. Evaluation of herbicides for control of reed canary grass (​Phalaris Arundinacea​). Natural Areas Journal 34: 459-464.   Balfour, J., and L. Banack. 2000. Burns Bog ecosystem review - Water chemistry: Report prepared for Delta Fraser Properties Partnership and the Environmental Assessment Office in support of the Burns Bog ecosystem review, with additional data collected on publicly owned lands conducted for the Environmental Assessment Office in association with the Corporation of Delta. EBA Engineering Consultants Ltd., Vancouver, BC.   Baugh, T., R. Evans, C. Stewart, and S. Artabane. 2011. Restoration of a southern Appalachian mountain bog: Phase I. Reed canary grass removal. Ecological Restoration 29: 13-14.   Bebeau, G. 2014. Reed canary grass. Friends of the Wild Flower Garden, Inc.   Bönsel, A., and A. Sonneck. 2011. Effects of a hydrological protection zone on the restoration of a raised bog: A case study from northeast Germany 1997-2008.​ ​Wetlands Ecology and Management 19: 183-194.   Burns Bog Conservation Society. 2016. Visit Burns Bog! Retrieved from: http://www.burnsbog.org/visitburnsbog/.   30   Burns Bog Conservation Society. (n.d.). Burns Bog Conservation Society plant guide. Retrieved from: https://www.burnsbog.org/bog/wp-content/uploads/BBCS-Plant-Guide1.pdf.   Canadian Wildlife Service. 1999. Invasive plants of natural habitats in Canada. Environment Canada Wildlife Habitat Conservation: 1-112.   Clements, D., K. Feenstra, K. Jones, and R. Staniforth. 2008. The biology of invasive alien plants in Canada. 9. ​Impatiens glandulifera​ Royle. Canadian Journal of Plant Science 88: 403-417.   Gillespie, J., and T. Murn. 1992. Mowing controls reed canary grass, releases native wetland plants (Wisconsin). Restoration and Management Notes​ ​10: 93-94.  González, E., L. Rochefort, S. Boudreau, S. Hugron, and M. Poulin. 2013. Can indicator species predict restoration outcomes early in the monitoring process? A case study with peatlands. Ecological Indicators 32: 232–238.   Gorham, E., and L. Rochefort. 2003. Peatland restoration: A brief assessment with special reference to Sphagnum ​bogs. Wetlands Ecology and Management 11: 109-119.   Hebda, R., K. Gustavson, K. Golinski and A. Calder, 2000. Burns Bog ecosystem review synthesis report for Burns Bog, Fraser River delta, southwestern British Columbia, Canada. Environmental Assessment Office, Victoria, BC.   Howie, S. 2012. Lagg characteristics of Burns Bog: Final report to Metro Vancouver Regional Parks (​Unpublished report​). Prepared for Metro Vancouver Regional Parks, Vancouver, BC.  Howie, S. 2013. Bogs and their laggs in coastal British Columbia, Canada: Characteristics of topography, depth to water table, hydrochemistry, peat properties, and vegetation at the bog margin (​Doctoral dissertation​), Simon Fraser University, Burnaby, BC.   Howie, S., and I. van Meerveld. 2011. The essential role of the lagg in raised bog function and restoration: A review. Wetlands 31: 613-622.  Howie, S., and I. van Meerveld. 2016. Classification of vegetative lagg types and hydrogeomorphic lagg forms in bogs of coastal British Columbia, Canada. The Canadian Geographer 60: 123-134.  Howie, S., P. Whitfield, R. Hebda, R. Dakin, and J. Jeglum. 2009. Can analysis of historic lagg forms be of use in the restoration of highly altered raised bogs? Examples from Burns Bog, British Columbia. Canadian Water Resources Journal 34: 427-440.   Howie, S., P. Whitfield, R. Hebda, T. Munson, R. Dakin, and J. Jeglum. 2009. Water table and vegetation response to ditch blocking: Restoration of a raised bog in southwestern British Columbia. Canadian Water Resources Journal 34: 381-392. 31     Hulme, P., and E. Bremner. 2005. Assessing the impact of ​Impatiens glandulifera ​on riparian habitats: Partitioning diversity components following species removal. Journal of Applied Ecology​ ​43: 43-50.   Invasive Plants of Southwestern BC. Reed canary grass. Retrieved from: http://www.shim.bc.ca/invasivespecies/_private/ReedCanary.htm.   Iroumé, A., A. Huber, and K. Schulz. 2005. Summer flows in experimental catchments with different forest covers, Chile.​ ​Journal of Hydrology 300: 300-313.   IUCN SSC Invasive Species Specialist Group. 2015. Management and control information ​Impatiens glandulifera ​Royle.   Kelly, J., C. Maguire, and P. Cosgrove. 2008. Best practice management guidelines: Himalayan balsam (​Impatiens glandulifera). ​Invasive Species Ireland Project​.   King County Noxious Weed Control Program. 2010. Policeman's helmet. Retrieved from: http://your.kingcounty.gov/dnrp/library/water-and-land/weeds/BMPs/policemans-helmet-control.pdf.   Kohl, P. 2011. Invasive plants. Monitoring Your Wetland: 1-8.   Oishi, A, R. Oren, K. Novick, S. Palmroth, and G. Katul. 2010. Interannual invariability of forest evapotranspiration and its consequence to water flow downstream.​ ​Ecosystems 13: 421-436.   Owens, K. 2015. Hydrology of the Delta Nature Reserve (​Unpublished report​). Prepared for the Burns Bog Conservation Society, Delta, BC.   Potvin, L., E. Kane, R. Chimner, R. Kolka, and E. Lilleskov. 2015. Effects of water table position and plant functional group on plant community, aboveground production, and peat properties in a peatland mesocosm experiment (PEATcosm). Plant Soil 387: 277-294.   Price, J., A. Heathwaite, and A. Baird. 2003. Hydrological processes in abandoned and restored peatlands: An overview of management approaches.​ ​Wetlands Ecology and Management 11: 65-83.  Rochefort, L., F. Quinty, S. Campeau, K. Johnson, and T. Malterer. 2003. North American approach to the restoration of ​Sphagnum​-dominated peatlands.​ ​Wetlands Ecology and Management 11: 3-20.   Thompson, D., and J. Waddington. 2008. ​Sphagnum​ under pressure: Towards an ecohydrological approach to examining ​Sphagnum​ productivity. Ecohydrology​ ​1: 299-308.   32   Tu, M. 2004. Reed canary grass: Control and management in the Pacific Northwest. Retrieved from: https://www.invasive.org/gist/moredocs/phaaru01.pdf.                                                     33   APPENDICES   Appendix 1.  Coordinates for dipwells in DNR that were used in this study. Dipwell # Latitude N Longitude W 2 49​o​ 8’ 42.998” 122​o ​56’ 1.000” 3 49​o​ 8’ 39.999” 122​o ​56’ 0.999” 6 49​o​ 8’ 31.001” 122​o ​55’ 51.998” Unmarked 49​o​ 8’ 33.999” 122​o ​55’ 55.997” I 49​o​ 8’ 28.000” 122​o ​55’ 42.999” II 49​o​ 8’ 30.000” 122​o ​55’ 35.000” III 49​o​ 8’ 35.999” 122​o ​55’ 42.998” IV 49​o​ 8’ 38.687” 122​o ​55’ 48.256”                      34   Appendix 2. Mean values for Water Table, pH, and electrical conductivity. Dipwell # Depth from Surface (cm) pH electrical conductivity (μS/cm) 2 20.07 4.28 64.73 3 19.85 4.03 85.55 6 20.62 4.27 88.65 Unmarked 28.38 4.03 98.72 I 30.95 3.70 164.40 II 13.40 4.16 117.80 III 25.98 3.98 105.00 IV 14.00 4.57 86.00 Overall 21.65 4.13 98.24    Appendix 3. Locations of trampling transects Control/ Ecosystem Transects 1- Salal Rich 4E, 5E 2- “Bog” 10W,12W/E,14W/E 3- Peat forest 19W, 23E, 28W       35   Appendix 4. Raw values for species cover for the west side of the boardwalk Transect No. / Species 10     12     14     19     28     Distance from Boardwalk (m) 0 1.5 5 0 1.5 5 0 1.5 5 0 1.5 5 0 1.5 5 Sphagnum 0 0 0 5 0 0 0 5 0 0 30 5 0 0 80 Salal 90 50 50 0 0 0 30 5 50 10 10 0 0 5 0 English Holly 0 0 0 0 0 0 0 0 0 5 5 0 0 0 0 Labrador Tea 0 5 10 95 100 100 60 90 50 0 0 0 0 0 0 Western Red Cedar 0 0 0 0 0 0 0 0 0 0 0 40 0 0 0 Spiny Wood Fern 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Step Moss 0 0 0 0 0 0 0 0 0 10 0 0 0 0 0 No Vegetation 10 45 40 0 0 0 10 0 0 75 55 55 100 95 20 Sum 90 55 60 100 100 100 90 100 100 25 45 45 0 5 80 Relative Cover 0.9 0.55 0.6 1 1 1 0.9 1 1 0.3 0.5 0.5 0 0.1 0.8             36   Appendix 5. Raw values for species cover for east side of the boardwalk Transect No. / Species 4     5     12     14     23     Distance from Boardwalk (m) 0 1.5 5 0 1.5 5 0 1.5 5 0 1.5 5 0 1.5 5 Sphagnum 0 0 5 0 0 0 0 0 0 0 0 0 50 40 40 Salal 0 40 50 60 80 90 10 5 0 10 0 0 20 30 40 English Holly 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Labrador Tea 0 0 0 15 15 10 90 95 100 90 100 100 0 0 0 Western Red Cedar 0 10 0 0 0 0 0 0 0 0 0 0 0 0 0 Spiny Wood Fern 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 Step Moss 0 0 15 0 0 0 0 0 0 0 0 0 0 0 0 No Vegetation 100 50 25 25 5 0 0 0 0 0 0 0 30 30 20 Sum 0 50 75 75 95 100 100 100 100 100 100 100 70 70 80 Relative Cover 0 0.5 0.8 0.8 1 1 1 1 1 1 1 1 0.7 0.7 0.8            37   Appendix 6.  Simpson’s diversity index by ecosystem Salal Distance from Boardwalk (m) 0.0  1.5  5.0  Plant species ni ni(ni-1) ni ni(ni-1) ni ni(ni-1) Sphagnum 1.50 2.24 0.00 0.00 0.05 0.00 Salal 0.00 0.00 1.70 2.87 1.90 3.59 English Holly 0.15 0.02 0.00 0.00 0.00 0.00 Labrador Tea 0.00 0.00 0.20 0.04 0.20 0.04 Western Red Cedar 0.00 0.00 0.10 0.01 0.00 0.00 Spiny Wood Fern 0.00 0.00 0.00 0.00 0.05 0.00 Step Moss 1.35 1.81 0.00 0.00 0.15 0.02 Total 3.00  2.00  2.35  Simpson’s Diversity 0.4532  0.7337  0.6645  Bog Distance from Boardwalk (m) 0.0  1.5  5.0  Plant species ni ni(ni-1) ni ni(ni-1) ni ni(ni-1) Sphagnum 0.05 0.00 0.05 0.00 0.00 0.00 Salal 0.50 0.25 0.10 0.01 0.50 0.25 English Holly 0.00 0.00 0.00 0.00 0.00 0.00 Labrador Tea 3.35 11.19 3.85 14.78 3.50 12.22 Western Red Cedar 0.00 0.00 0.00 0.00 0.00 0.00 Spiny Wood Fern 0.00 0.00 0.00 0.00 0.00 0.00 Step Moss 0.00 0.00 0.00 0.00 0.00 0.00 Total 3.90  4.00  4.00  Simpson’s Diversity 0.7538  0.9270  0.7807  38   Peat Forest Distance from Boardwalk (m) 0.0  1.5  5.0  Plant species ni ni(ni-1) ni ni(ni-1) ni ni(ni-1) Sphagnum 0.50 0.25 0.70 0.48 1.25 1.55 Salal 0.30 0.09 0.45 0.20 0.40 0.16 English Holly 0.05 0.00 0.05 0.00 0.00 0.00 Labrador Tea 0.00 0.00 0.00 0.00 0.00 0.00 Western Red Cedar 0.00 0.00 0.00 0.00 0.40 0.16 Spiny Wood Fern 0.00 0.00 0.00 0.00 0.00 0.00 Step Moss 0.10 0.01 0.00 0.00 0.00 0.00 Total 0.95  1.20  2.05  Simpson’s Diversity 0.3841  0.4783  0.4452   Appendix 7.  The Restoration and Recovery of the Delta Nature Reserve: a Literature Review  Introduction Burns Bog, located in Delta, BC, is the only estuarine raised peat bog found in western                Canada. The bog acts as a large carbon sink, and also provides a habitat for many vulnerable and                  endangered species. The resilience of this fragile, rare ecosystem is vital in order to ensure it                persists far into the future. There are many hydrological and biological factors that must be taken                into consideration when analysing the health of the ecosystem and its potential restoration. This              literature review will act as a foundation of knowledge necessary to work towards the restoration               of the Delta Nature Reserve. This will be achieved through the review of past studies in similar                 ecosystems. A second item of concern within this ecosystem is the observed presence of invasive              species along the periphery of the Delta Nature Reserve, specifically on the banks of the stream                that flows there. The two main invasive species that have been observed are ​Phalaris              arundinacae, ​or reed canary grass, and Impatiens glandulifera, ​or policeman’s helmet. These two             plant species display all of the qualities of an invasive species that make them difficult to                eradicate - effective dispersal, fast reproduction, and quick growth rate. The process of complete              39   removal of the two invasive species from the Delta Nature Reserve must also aim to minimize                damage to the surrounding ecosystem. This literature review aims to pinpoint both economically             and ecologically feasible removal strategies of reed canary grass and policeman’s helmet from             the Delta Nature Reserve.  Background Information Burns Bog, due to its hydrological, biological, and topographical features, is classified as             a raised peat bog. These features include an internal water mound, nutrient-poor and acidic water               from precipitation, a two-layered composition, and peat-forming biological communities (Howie          et al., 2011). The Burns Bog lagg zone within the Delta Nature Reserve is located at the bog                  perimeter on the north side. The lagg zone acts as a buffer between the higher nutrient waters                 surrounding the bog and the nutrient-poor waters within. This buffering system is crucial in              maintaining the unique biological communities within the bog, such as ​Sphagnum ​moss. Along             with water chemistry, a high water table is critical to peat communities. Therefore inflows of               water from precipitation must meet water amounts lost to evaporation, transpiration, and runoff             (Howie ​et al., ​2009).  Over the span of the UBC Environmental Sciences community project, one focus was to              begin monitoring the water table height, pH, and electrical conductivity of the groundwater             within the Delta Nature Reserve. This was done in order to set a framework for the continued                 monitoring of the hydrology in the lagg zone of Burns Bog. The pH and electrical conductivity                are useful indicators for monitoring the ecological succession of the lagg zone in response to               recovery efforts (Gorham ​et al., ​2003). There are several restoration strategies that focus on              restoring the water table, including blocking ditches, bunds and terracing, and using mulch             (Howie ​et al., ​2011). It is our hope that this foundation of data, along with a proposed plan for                   monitoring in the years to come, can be used to help educate others and preserve the Delta                 Nature Reserve.  Bog hydrology also has a large impact on the biology of the area, as does human activity.                 One of the most influential species present in the Delta Nature Reserve is ​Sphagnum moss,               which is a species that is responsible for almost half of the carbon accumulation in peatlands                (Thompson and Waddington, 2008). Studies observe that ​Sphagnum ​cover and production is at             its highest when the bog’s water table is sufficiently high (Potvin ​et al., ​2015), which displays                the dependence of ​Sphagnum ​moss on a moist environment. In the Delta Nature Reserve, a               lowered water table would lead to a decrease in ​Sphagnum ​abundance, allowing for the growth               of other native species such as Salal. This increase in the abundance of Salal has already been                 observed in parts of the Delta Nature Reserve.  40   Restoration of Hydrology In most North American raised peat bog restoration projects, those involved have            concentrated on the re-establishment of ​Sphagnum ​moss without addressing the main stressor,            dry conditions. For bog vegetation to persist, a high water table must be present, and therefore                the restoration of bog hydrology should begin if not prior to then along with vegetation               restoration (Howie and van Meerveld, 2011). There are a variety of methods that have been used                in bog rewetting, including ditch-blocking, bund and dyke construction, and excavating water            retention basins (Bönsel and Sonneck, 2011; Howie ​et al., ​2009; Rochefort ​et al., ​2003).              Removal of tall trees can also be done, as they utilize much of the water resources within the                  area. Along with these alterations of the habitat, extensive long-term monitoring must take place              in order to assess the successes of the restoration project.  The Delta Nature Reserve is a fragile, relatively small ecosystem located close to             residential and industrial areas, and has a small salmon-bearing creek running along its             periphery. These factors must be considered when deciding which hydrological restoration           methods to undergo. Methods involving large, heavy machinery may not be feasible or may do               more harm to the ecosystem than good, such as excavation of water retention basins or dyke                construction. However, there are alternative methods of hydrological restoration that could suit            the specific needs of the Delta Nature Reserve that would not require heavy machinery. Within               Burns Bog proper, Howie ​et al. ​(2009) completed a project involving ditch-blocking to restore              parts of the bog’s hydrology and ​Sphagnum ​communities. Plywood that was secured with             wooden stakes was used to block ditches, and were covered in peat and at times native                vegetation (Howie ​et al., ​2009). Supplies were brought to the problem areas on foot (Howie ​et                al., ​2009). To assess the long-term success of this project, water table and bog surface elevation                samples have been obtained monthly since 2005 (Howie ​et al., ​2009). Potential draining ditches              around the Delta Nature Reserve would have to be assessed in order to analyse whether this is a                  valuable method of hydrological restoration. Methods such as these that minimize further            damage to the ecosystem could be utilized in the Delta Nature Reserve to restore the area’s                hydrological function.   Restoration of ​Sphagnum ​Moss Communities Once a plan is underway to restore the area’s hydrological function, the successful             restoration of ​Sphagnum ​moss can be completed. ​Sphagnum ​moss relies heavily on a moist              environment, and therefore requires an environment in which the water table is sufficiently high.              There have been many restoration studies completed in which ​Sphagnum ​moss readily            re-established once the bog hydrology had been restored. In the study completed by Bönsel and               Sonneck (2011), ditch-blocking was completed in order to simulate a return to moist bog              conditions. Site monitoring of water levels and vegetation began before the restoration attempts             41   began to form an appropriately large collection of data (Bönsel and Sonneck, 2011). It was found                that after the ditch-blocking occurred, continuous high water levels were established, and a             diverse ​Sphagnum ​community was able to establish itself (Bönsel and Sonneck, 2011). In             addition to ​Sphagnum ​communities re-establishing, tree cover significantly decreased due to high            water level and increased acidity released into the soil from ​Sphagnum ​moss (Bönsel and              Sonneck, 2011). This project is one example of how the proper restoration of bog hydrological               features can aid in the restoration of the highly important bog species, ​Sphagnum. In some situations, ​Sphagnum ​moss communities are unable to establish on their own,             and additional steps must be taken in order to ensure their establishment. Natural colonization of               Sphagnum ​moss can be supplemented with transplanting from other natural bog locations,            seeding, or dispersing ​Sphagnum ​diaspores (Howie and van Meerveld, 2011). In a study             completed by Rochefort ​et al. (2003), following hydrological restoration, ​Sphagnum ​was           re-established through collecting the top 10 cm of natural bog cover to obtain diaspores for               spreading. Diaspores were then covered by straw mulch, in order to improve temperature             conditions and water availability for the growing ​Sphagnum (Rochefort ​et al., ​2003).            Additionally, in some areas phosphorus fertilization was done, which encourages the growth of             vascular plants, in turn stabilizing the bare peat surface and acting as a habitat for establishing                Sphagnum​ (Rochefort ​et al., ​2003).  In the Delta Nature Reserve, it has been observed that Salal has been encroaching on               Sphagnum ​communities. This could possibly be due to an overall drying out of the area, allowing                vascular plants to take root and preventing ​Sphagnum ​from competing effectively. The            Corporation of Delta, alongside the Burns Bog Conservation Society, would have to decide if              removing Salal to allow for the growth of ​Sphagnum ​moss is within their interests. Another               option would be to allow the native Salal to continue growing in areas previously inhabited by                Sphagnum, ​as it is not an invasive species and simply signifies a transition in the ecological                composition of the area from bog-like to forest-like. Patches of ​Sphagnum ​that have died due to                drying out or human trampling could be restored using methods mentioned above, such as              broadcasting diaspores and using fertilization, or simply allowed to re-establish on their own. An              important step in the restoration process would, again, be to address the stressors that cause               Sphagnum to die. In this case, those stressors are likely a low water table and trampling of                 Sphagnum near the boardwalks by Reserve visitors. Once the stressors have been addressed, the              restoration of a diverse ​Sphagnum ​community should be straightforward and successful in the             Delta Nature Reserve.    42   Reed Canary Grass  Figure 16. ​Reed canary grass in seed. Picture retrieved from: http://www.friendsofthewildflowergarden.org/pages/plants/reedcanarygrass.html  Along the Northeast side of the Delta Nature Reserve runs a North-flowing man-made             stream that drains the residential neighbourhoods above it. This stream, though originally            excavated as a method of drainage, has become a salmon-bearing stream and supports a small               ecosystem. However, because of human disturbances, invasive species have spread along its            banks in close proximity to the fragile ecosystem of the bog within the Reserve. One in                particular, ​Phalaris arundinacea, or reed canary grass, has the ability and tendency to form              dense, monotypic stands in areas it has colonized (Bahm ​et al., ​2014). Reed canary grass is a                 perennial, and can reproduce both sexually through seeds and asexually through vegetative            rhizome growth (Canadian Wildlife Service, 1999). Reed canary grass, once established, has            been shown to be extremely difficult to eradicate, and because of the sensitivity of the               surrounding ecosystem, removal methods must be effective yet minimally toxic. The           above-ground biomass, rhizomes, and seed bank must be targeted for complete, long-term            eradication (Gillespie and Murn, 1992). According to Bahm ​et al. ​(2014), hand-pulling of reed canary grass can be a successful               means of removal, requires a significant time investment and is better suited to small              infestations. Plowing is a method suited to when native species are present in sufficiently high               numbers to establish in the place of reed canary grass (Bahm ​et al., ​2014). Fire can be used as                   tool to reduce litter, making herbicide treatment more effective; however, herbicide treatment is,             43   again, only truly successful when there are native species present to take over (Bahm ​et al.,                2014).  In a study completed by Baugh ​et al. ​(2011), the herbicide Glyphosate was applied to               uncut flowering reed canary grass stems in June and July. The herbicide was broadcast over               monocultures of reed canary grass, and in transition zones, the grass was first cut, then allowed                to regrow to about 50 cm in height, then sprayed (Baugh ​et al., ​2011). This method used in                  transition zones allowed for precise application of the herbicide in order to minimize impact on               native species (Baugh ​et al., ​2011). Small infestations of the grass were either removed by hand                or spot-treated with Glyphosate (Baugh ​et al., ​2011). Since the treatments, long-term monitoring             has been underway to observe for resprouts or seedling emergence (Baugh ​et al., ​2011). It has                been found that so far, there has been a near-complete kill of reed canary grass in areas sprayed                  with Glyphosate (Baugh ​et al., ​2011). The combined method of herbicide spray and mechanical              removal seems to be effective in this mountain bog. Herbicide use was also discussed by the Canadian Wildlife Service (1999), who state it              seems to be the most effective if applied at the right time of year. This depends on the herbicide                   used - some are best used in the dormant season, and others in flowering season (Canadian                Wildlife Service, 1999). As mentioned previously, herbicides are the most effective when there             are native species present to colonize the area, otherwise nearby stands of reed canary grass               could replenish the treated area. According to Gillespie and Murn (1992), herbicides can only be               used near aquatic systems if they contain a surfactant that is approved for aquatic systems. In the                 Delta Nature Reserve, the health of the salmon-bearing stream would have to be taken into               consideration if the chosen method of eradication were to be herbicide use.  A series of other possible removal methods of reed canary grass are outlined by Gillespie               and Murn (1992), including burning, excavation, planting vegetation, mowing, altering          hydrology, and mulching or solarizing. Burning is beneficial as it removes biomass and litter of               reed canary grass, and may kill seeds on the surface, but could also release the seed bank of                  undesirable species and stimulate dormant buds of reed canary grass to resprout (Gillespie and              Murn, 1992). Excavation removes plant rhizomes and the seed bank, but also removes sediment              and nutrients, and can alter hydrology (Gillespie and Murn, 1992). Planting vegetation such as              trees and shrubs can shade out reed canary grass, and adds structure and diversity to the                ecosystem, but reed canary grass must be managed for the 3-5 years it would take for plant                 seedlings to establish (Gillespie and Murn, 1992). Altering hydrology prevents reed canary grass             germination and kills plant rhizomes, but high water levels would need to be maintained              throughout the growing season (Gillespie and Murn, 1992). These high water levels could also              encourage the growth of native species such as cattails and bulrush. Finally, mowing and              solarizing kills adults and rhizomes, but is non-selective and can have an impact on soil               44   microorganisms (Gillespie and Murn, 1992). It is possible that some of these removal methods              could be used in the Delta Nature Reserve to aid in the eradication of reed canary grass. Much like the ​Sphagnum ​restoration, with the issue of reed canary grass, the potential              reasons why it established in the first place should be addressed; the stressors that disturbed the                ecosystem to allow for reed canary grass to infiltrate should be removed if still present. More                diverse sites respond to restoration efforts better, so if possible, the establishment of native              species should also be done so that they can take over areas where reed canary grass has been                  removed. Continued monitoring and treatment would be required for up to 5-10 years to ensure               complete removal of reed canary grass (Tu, 2004). Along with long term monitoring, an adaptive               management approach should be utilized in order to effectively remove the species (Tu, 2004).  Policeman’s Helmet  Figure 16. ​Policeman’s helmet in bloom. Picture retrieved from: http://www.kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-identification/policemans-helmet.aspx  A second invasive species of concern along the periphery of the Delta Nature Reserve is               Impatiens glandulifera, ​also known as Himalayan balsam, or more commonly in Canada,            Policeman’s helmet. The species was originally introduced to North America as an ornamental             plant, and proceeded to spread (KCNWCP, 2010). Policeman’s helmet is an annual plant             45   typically found in riparian habitats, and prefers moist soils and partially shaded to sunny              environments (KCNWCP, 2010). The plant grow to a height of between 3-8 feet, and has pink or                 purple flowers that resemble a policeman’s helmet (Clements ​et al., ​2008). Seeds are dispersed              explosively from parent plants, and can remain viable for up to 18 months as they are dispersed                 along adjacent waterways. The negative impacts of Policeman’s helmet are plentiful - the large              plant tends to shade out native species, compete for pollinators such as bees, and cause stream                bank erosion after it dies out in the fall (Kelly ​et al., ​2008). Stands of Policeman’s helmet have                  been observed in the Delta Nature Reserve. For the most part, physical removal of Policeman’s helmet has been shown to be a               successful means of removal due to the plant’s modest root system (IUCN, 2015). Small              infestations can easily be hand-pulled or dug up, which should be done in the spring or early                 summer when seeds have not yet fully developed (KCNWCP, 2010). Plant parts should be              properly disposed of to minimize the risk of recolonization; flower heads should be cut and               bagged, and disposed of in the garbage (KCNWCP, 2010). Stems can be piled upon tarps (to                prevent rooting) and composted (KCNWCP, 2010).  Larger infestations can be controlled through mowing - plants should be cut below their              lowest nodes in order to prevent regrowth (Kelly ​et al., ​2008). Continued monitoring is required               to identify areas of plant regrowth; these areas can be hand-pulled or mowed once more               (KCNWCP, 2010). While larger infestations can be controlled through the use of the herbicide              Glyphosate, this is not advisable in riparian areas as the herbicide does not contain suitable               surfactants (Clements ​et al., ​2008). As with smaller infestations, all plant parts should be              disposed of properly to prevent regrowth of the stands. When completing removal, barriers should be placed to prevent removed vegetation from            entering the waterway, as the plant can be further spread in this fashion (KCNWCP, 2010).               Along with barriers, removal processes should be completed while attempting to minimize            disturbance, along with synchronously planting native species (Clement ​et al., ​2008). The            removal of Policeman’s helmet has been shown to lead to an increase in species richness, and                this process can be facilitated with the planting of native species (Hulme and Bremner, 2005).               Planting should also be done to prevent the erosion of the stream bank (KCNWCP, 2010). Policeman’s helmet, which has been observed along with reed canary grass in the Delta              Nature Reserve, can be controlled by the Corporation of Delta through physical removal and the               proper disposal of plant parts. Hand-pulling of small infestations is successful if done in the               spring or early summer. For larger stands, mowing has been shown to be successful, especially if                plants are cut below their lowest node to prevent regeneration. Continued monitoring of the site               after removal is crucial, and any signs of regrowth can be spot treated through hand-pulling or                cutting. As the infestation is near a stream, barriers should be placed when removing the species                46   in order to prevent spread of vegetative matter and seeds downstream. Through physical             removal, Policeman’s helmet can be removed in a relatively straightforward fashion.  Conclusions Burns Bog, located in Delta, BC, is a very unique ecosystem, and the only estuarine               raised peat bog found in western Canada. The bog provides many ecosystem services, including              acting as a large carbon sink, and it provides a habitat for many vulnerable and endangered                species. Throughout recent years, the ecosystem has appeared dryer than what is considered             suitable for a bog environment. There has also been an encroachment of species such as Salal                that prefer drier environments on bog species such as ​Sphagnum ​moss. Along with more Salal,               the increased presence of invasive species reed canary grass and Policeman`s helmet have been              observed. While hydrological restoration methods in the Delta Nature Reserve that involve heavy            machinery are not feasible, there are small-scale methods that may be possible to restore the               water table. Ditch-blocking is a method that could be utilized, as used by Howie ​et al. ​(2009) in                  Burns Bog proper, using plywood and securing it with wooden stakes to block ditches. Supplies               could be brought in on foot to minimize impacts on the ecosystem. A long-term monitoring               project should be implemented in order to assess the success of this hydrological restoration              plan. The hydrology restoration should be addressed before or alongside ​Sphagnum ​moss            restoration, which requires suitably high water content to survive. ​Sphagnum ​moss restoration            can also be aided through moss transplants, distributing diaspores, or fertilization. Reed canary grass, which is found in high abundances along the stream in the Delta               Nature Reserve, has high seed counts and can reproduce both sexually and vegetatively through              rhizome growth; these factors make it extremely difficult to completely eradicate. If possible, the              establishment of native species should be done in synchrony with the removal of reed canary               grass to help prevent its continued monoculture on the stream banks. Since reed canary grass is                observed in such high quantities, mechanical removal such as hand-pulling is not feasible for the               Delta Nature Reserve. Mowing is a viable option, as long as mowed stalks are then shaded out                 with plastic or mulch in order to prevent vegetative growth. Herbicides can also mindfully be               applied, but only if said herbicides contain a surfactant approved for aquatic systems. Long-term              monitoring and removal would be required to ensure the complete removal of the invasive              species. Policeman’s helmet can be removed in a more straightforward approach. The species is             more easily removed through physical means such as hand-pulling, though it must be ensured              that all of the plant parts are removed and properly disposed of. Barriers should be placed along                 the stream as removal takes place to ensure that no seeds or plant matter enter the waterway, as                  47   seeds can persist in water for many months. Mowing can also be done and is most successful                 when plants are cut below their lowest nodes to prevent regeneration. As with reed canary grass,                long-term monitoring should be implemented in order to maintain complete eradication. 48 

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