摘要
深秋落叶前后杨树各部位养分贮量发生巨大变化。叶是生长中杨树的重要养分库,叶中N的贮量可占全树N总贮量的2/3,P、K分别可占1/3。落叶时叶中N贮量的60%和P贮量的50%向外输出,因此落叶中只含少量的N和P,但K含量几乎不变,Ca,Mg、Si含量明显增加。树干、枝和根是N、P和有机养分的冬季贮存库,冬季这些部位的N、P贮量比夏季高得多,但K、Si的贮量略有减少,Ca贮量几乎不变,Mg贮量略有增加。
There are big changes of nutrient storage in different parts of poplar tree before and after leaf fallen in west Liaoning. Foliage is the major nutrient pool for the growing poplar tree. Its N storage is about two third of N in total and P and K are more than one third. 60% of N and 50% of P in foliage are transferred to other parts of the tree during leaf fallen, with K content almost unchanged and Ca,Mg and Si contents significantly increased.The trunk, branch and root are the reservoirs for N,P and organic nutrients in winter,their storage of N and P is much higher than in sumer,but that of K and Si is slightly decreased.Ca is almost unchanged and Mg is slightly increased.
出处
《应用生态学报》
CAS
CSCD
1992年第4期296-301,共6页
Chinese Journal of Applied Ecology
基金
国家自然科学基金
关键词
杨树
养分含量变化
Poplar tree,Nutrient content change.