杉木林群体光能利用研究

用半叶法测定杉木林分光合强度，可看出，杉木林的光合强度不但与叶量有关，且还与叶子质量、空间结构有关；增加树冠长度，能使叶子受光均匀，增大净光合强度；光照强度６０％时，杉木林净光合强度最大，大于或小于６０％都不利于光合强度的提高。杉木林叶子能制造３ｋｇ／ｈｍ２·ｈ左右的干物质，叶于制造的有机质只有５％转化为树干材积，这个转化率随每公顷断面积的增加而增加，幼林时期适当增加密度，有利于提高林地生产力．

Study on Light Energy Utilization of Chinese Fir Population

Determination of photosynthetic intensity of Chinese fir (Cunninghamia lanceolata)forest showed that it had close relation with leat quantity, leaf quality and spatial structure.Increase length of crown could make leaves open evenly and also could increase net photosynthetic intenslty. When photosynthetic intensity was 60%, net photosynthetic intensity of chinese fir population was the biggest. Leaves of the population could praduce 3 kg/ha.h of dry matter.Organic matter produced by leaves transformed only 5% into volume of tree.