Tree Growth Prediction in Relation to Simple Set of Site Quality Indicators for Six Native Tree Species in the Philippines

Table 3

Set of site quality indicators used in four (additive) steps of analysis.

Site Indicator	Parameter	Unit/Classification
(1) Landscape position	Orientation	1-N, 2-NE, 3-E, 4-SE, 5-S, 6-SW, 7-W, 8-NW
	Slope position	1-Summit, 2-Upper, 3-Lower, 4-Bottom
(2) Soil Type	Soil class	Based on USDA
(3) Soil physical properties	Sand	Content of sand (%)
	Silt	Content of silt (%)
	Bulk density	Bulk density (g/cm^3)
(4) Soil chemical properties	pH	Soil pH using 1 : 1 soil water ratio
	Organic matter	Content organic matter (%)
	Nitrogen	Total 𝑁 (mg/kg)
	Phosphorus	Extractable-𝑃 (me/kg)
	Potassium	Exchangeable-𝐾 (me/kg)