UBC Theses and Dissertations
A general theory on common point intersect sampling with special application to downed woody particles Egglestone, Jeffrey N.
A general sampling theory referred to as common point intersect sampling is developed and assessed. This new technique is specifically applied to the problem of estimating parameters of populations of downed woody particles of interest in fire research. The performance of the common point intersect sampling method is compared to that of the well-established line intercept technique with respect to two lesser (less than 3 inches in diameter) downed woody particles populations. Results of these tests indicate that proper application of the new sampling system can yield total volume estimates of approximately 15 per cent precision with savings of up to 40 per cent of the total sampling time required by the line intercept technique. The common point intersect sampling method is demonstrated to be a useful approach to solving the problem of obtaining estimates for numerous attributes of populations of downed woody particles. General formulas are also provided which facilitate the application of common point intersect sampling to the task of obtaining parameters of standing timber such as crown area and average crown diameter from aerial photographs. The common point intersect technique is shown to be a fast and accurate means of sampling forest material. The new sampling system has been applied rigorously in only one problem area. The general nature of the common point intersect system suggests, however, that it has many other applications in a multiplicity of scientific disciplines.
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