辽东山区不同森林植被类型枯落物层截留降雨行为研究

Modes of litter interception rainfall of different forest vegetation types in mountainous areas of eastern Liaoning

对辽宁东部山区具有代表性的油松林、落叶松林、红松林、柞木林及杂木林 5种森林植被类型枯落物层截留降雨行为进行了比较研究。结果表明 ,枯落物截留量随林内雨量的增加而增加 ,呈显著的线性关系 ;枯落物截留率在低的林内雨量级时下降梯度较大 ,以后随林内雨量增大而逐渐减少 ,最后趋于某一定值 ,枯落物截留达到饱和。曲线估计的饱和截留率为 :杂木林 30 % ,柞木林2 3% ,落叶松林 2 0 % ,油松林 15 % ,红松林 10 %。林冠层与枯落物层截留量依林外雨变化呈显著的线性关系 ,总截留率在低雨量级时保持在较高的水平 ,随后急剧下降 ,并逐渐趋于某一稳定值 ,达到最大截留能力。由曲线推算的最大总截留率 ,杂木林和柞木林为 4 5 % ,落叶松林为 4 0 % ,红松林和油松林约为 30 %。枯落物生长季相对于林内雨的截留率为 14 .31%～ 4 3.15 % ,平均值为 31.15 % ,相对于林外雨量的截留率为 11.15 %～ 32 .30 % ,平均值为 2 4 .0 5 %。

Comparative studies were conducted regarding modes of litter interception rainfall of such 5 representative forest vegetation types as Pinus tabulaeformis stands,larch stands,P. koraiensis stands, stands of oaks and miscellaneous trees in mountainous areas of eastern Liaoning. The results indicated that litter interception quantity increased as the rainfall increased in forest,and presented a remarkable linear relationship; litter interception rates decreased significantly while the rainfall class in forest was low, then decreased gradually as the rainfall increased in forest, and headed for a specific value at last, litter interception tended to be saturated. The saturated interception rates estimated by curves were 30% for stands of miscellaneous trees, 23% for stands of oaks, 20% for larch stands, 15% for P. tabulaeformis stands and 10% for P. koraiensis stands, respectively. Interception quantities of canopies and litter assumed significantly linear relationship according to the changes of rainfall outside forests, total interception rates kept at a high level while the rainfall class was low, then decreased sharply and headed for a stable value gradually and the highest interception capacity was obtained. The biggest interception rates calculated by curves were 45% for stands of oaks and miscellaneous trees, 40% for larch stands, approximated 30% for P. koraiensis and P. tabulaeformis, respectively. The litter interception rate for the rainfall in forest during growing seasons was 14.31%～43.15%, the average value was 31.15% ; the litter interception rate for rainfall outside forest was 11.15%～32.30%, the average value was 24.05%.