Predicting soil and forest floor carbon stocks in Western Anatolian Scots pine stands, Turkey

Abstract

The objective of this study was to determine the models which estimate the soil plus forest floor carbon stocks (TC) using some stand, climate, and topographic parameters in Scots pine (Pinus sylvestris L.) stands. 40 sample plots were taken from sites differing in aspects, elevation, slope degree, slope position, and stand growth condition. TC of the stands, as dependent variables, and stand, climate, and topographic properties, as independent variables, were determined and evaluated with multiple regression analysis (MRA) and classification and regression tree technique (CART). In conclusion, TC were related with elevation, slope degree, slope position, aspect, actual evapotranspiration, mean annual precipitation, length of vegetation period, rainfall in the driest month, rainfall from June to September, stand volume, and site index. 91% of the variance in TC was explained with CART while 60% with MRA in a local scale. The results showed that soil and forest floor might become a carbon source where the rainfall decreased, but a sink, especially in productive sites where rainfall of the driest month increased. Key words: Carbon stocks, forest floor, regression tree, Scots pine, soil.