Comparison of -Square, Point Centered Quarter, and -Tree Sampling Methods in Pittosporum undulatum Invaded Woodlands

Table 2

Different sampling methods and estimators used in this study (adapted from [1]).

Sampling methods	Estimators		Characteristic
-Square		[13]	λ = estimated density; = sample size; = distance from closest individual to nearest neighbor; = distance from random point to closest individual
		[14]
		[20]
		[26]
Point Centered Quarter		[15]	= estimated density; = sample size; = number of individuals to be located in each sector of the area around the random sampling point; = distance from random point to closest individual in quarter
		[3]
		[24]
-tree		For 3-tree	= sample size; = estimated density; = plot area in each plot is calculated separately using the following equation: ⁢; = plot radius and in normal method prolongs to mid diameter of th tree but in adjusted methods prolongs between and trees.
		3-tree adjusted
		For 4-tree
		4-tree adjusted
		For 5-tree
		5-tree adjusted
		For 6-tree
		6-tree adjusted [16]