坡位对杉木×闽粤栲混交林和杉木纯林养分积累的影响

选择福建省建阳范桥国有林场16年生杉木×闽粤栲混交林与杉木纯林为研究对象,对不同坡位不同林分养分积累量进行分析对比。结果表明:上坡立地条件下,杉木纯林乔木层N、P、K养分积累量均大于杉木×闽粤栲混交林。中坡和下坡林分乔木层养分积累量则表现为混交林大于杉木纯林。不同林分乔木层养分积累量均占整个林分养分积累总量的90%以上,且表现为N>K>P和下坡>中坡>上坡。上坡杉木纯林的灌木层和草本层N、P积累量均大于混交林,下坡林分的灌木层N、P、K养分积累量均表现为杉木×闽粤栲混交林大于杉木纯林。不同林分凋落物的N和P的积累量均大大超过草本层和灌木层的积累量。

Effect of Slope Position on Nutrient Accumulation of Chinese fir Plantation and Its Mixed Forest with Castanopsis fissa

The plantation of 16-year-old Chinese fir(Cunninghamia lanceolata) and its mixed forest with Castanopsis fissa were chosen as research object in Fanqiao National Forest Farm in Jianyang of Fujian Province,and the nutrient accumulation of different forest stands in different slope position were determined and analyzed.The results showed that:in uphill stand conditions,N,P,K nutrient accumulations of pure Chinese fir tree layer were more than the accumulations of Chinese fir with C.fissa mixed forests.Tree layers,which lied on mid slope and downhill,nutrient accumulation of mixed forests was more than pure Chinese fir forests.The nutrient accumulations of tree layers took up more than 90% of the total amount of nutrient accumulation in different forest stands,and the law showed N>K>P,downhill>mid slope>uphill.N,P accumulations of shrub and herbaceous on uphill pure Chinese fir forests were more than those in mixed forests,the laws of N,P,K accumulations of shrubs in downhill stand showed that the fixed forests were more than the pure Chinese fir forests.The N and P accumulation quantity of litter were considerably more than the herb and the shrub layer in different forest stands.