International Journal of Forestry Research

Research Article

Effects of Soil Compaction and Relative Light Intensity on Survival and Growth Performance of Planted Shorea macrophylla (de Vriese) in Riparian Forest along Kayan Ulu River, Sarawak, Malaysia

Table 4

Stepwise multiple regression analysis on the survival and tree growth parameters (MAIH, MAID, and MAIV) in relation to explanatory environmental factors (soil compaction and relative light intensity).


		Explanatory Variables
		Soil Penetration Resistance				Relative Light Intensity	Adjusted R²
	Depth	0-10 cm	10-20 cm	20-30 cm	30-40 cm	Relative Light Intensity	Adjusted R²

Dependent Variables	Survival	-0.352	-0.360	-0.291	-0.238	0.359	-
	MAIH	-0.372	-0.250	-0.222	0.031	0.375	-
	MAID	-0.534	-0.533	-0.550	-0.340	0.550	0.424
	MAIV	0.266	-0.200	-0.178	-0.184	0.170	-

MAIH, mean annual increment in height; MAID, mean annual increment in diameter; MAIV, mean annual increment in volume.
Standardized regression coefficients, significant level, and adjusted R² values are given. n=24. : correlation is significant at P < 0.01, using Pearson correlation matrix. Unsuitable explanatory variables were excluded by the stepwise procedure.