千烟洲试验区人工林养分循环的研究

对中国科学院千烟洲试验区人工林的养分生物循环进行了研究。结果表明，湿地松和马尾松人工林中的N、P和K养分元素积累量分别占7种元素积累量的41．8％和46．6％。而木荷林只占22．9％，说明了湿地松和马尾松人工林生产1t干物质生物量要比木荷人工林消耗更多的N、P和K养分元素。通过降雨淋溶归还给3个林分的7种养分元素量，分别为相应林分凋落物中的养分元素归还量的0．29倍、0．20倍、0．15倍。按林分生物循环特点可把该试验区的人工林划分为：湿地松林和马尾松林为高存留、低归林，木荷林为高归还、低存留量两种类型。前者易消耗地力，后者则能改善林地土壤肥力。

Studies on Nutrient Biological Cycling in Plantaions in Qianyanzhou Experimental Area

Biological cycling of nutrient elements (N,P,C,Ca,Mg,Fe,Mn)was studied in the secondary Pinus ellionttii, Pinus massoniana and Schina superba stands. The research results:the accumulation of N,P and K in the Pinus ellionttii,Pinus massoniana and Schina superba stands were 42.8%,41.8% and 22.4% of the total respectively. The consumption of N, P and K of the secondary pine for making 1 ton organic material was more than that of the two other stands. The nutrient biocycling of the three stands was divided into two types, high retention and lower return, lower retention and high return. The Pinus ellionttii and Pinus massoniana be long to the former and the Schina superba to the latter.