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Confident Estimation for Density of a Biological Population Based on Line Transect Sampling
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作者 Ren-bin Gong Yun-bei Ma Yong Zhou 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第1期79-92,共14页
Line transect sampling is a very useful method in survey of wildlife population. Confident interval estimation for density D of a biological population is proposed based on a sequential design. The survey area is occu... Line transect sampling is a very useful method in survey of wildlife population. Confident interval estimation for density D of a biological population is proposed based on a sequential design. The survey area is occupied by the population whose size is unknown. A stopping rule is proposed by a kernel-based estimator of density function of the perpendicular data at a distance. With this stopping rule, we construct several confidence intervals for D by difference procedures. Some bias reduction techniques are used to modify the confidence intervals. These intervals provide the desired coverage probability as the bandwidth in the stopping rule approaches zero. A simulation study is also given to illustrate the performance of this proposed sequential kernel procedure. 展开更多
关键词 Line transect sampling Confident interval estimation Stopping rule Bias reduction
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Comparison of fixed area and distance sampling methods in open forests:case study of Zagros Forest,Iran 被引量:1
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作者 Mehrdad Mirzaei Amir Eslam Bonyad 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期1121-1126,共6页
The main aim of this study was to evaluate methods for fixed area and distance sampling in the Zagros open forest area in western Iran. Basic forest management and planning required appropriate quantitative and qualit... The main aim of this study was to evaluate methods for fixed area and distance sampling in the Zagros open forest area in western Iran. Basic forest management and planning required appropriate quantitative and qualitative information. Two sampling methods were compared on the basis of the actual means of characteristics derived from the 100 % survey. In total, 37 sampling plots were systematically installed with a grid of 100 m × 100 m in the study area. Density, crown canopy, and basal area of the stands were measured. The 100 % survey showed that tree density above 12.5 cm diameter at breast height was 68.04 stem ha-1, basal area was 15.16 m2 ha-1 and crown canopy percentage was 35.71% ha-1. The values for the traits determined by the two sampling methods differed significantly (P = 0.05). When the time required for the methods was compared, transect sampling required less than systematic-random sampling. Therefore, the transect sampling method was the more economical method for the Zagros open forests. The transect sampling method was statistically defensible and practical for quantitating characteristics of the Zagros open forests. 展开更多
关键词 Ilam - Systematic random sampling transect sampling Zagros Forest
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