杉木-山苍子-作物复合经营模式土壤肥力的研究

通过对杉木-山苍子(A)、杉木-山苍子-黄豆(B)、杉木-山苍子-烟叶(C)及对照的纯杉林土壤生物学活性、土壤化学性质、土壤结构、孔隙组成和水分性状等研究,结果表明:模式B、C表层土壤结构性状变差,土壤营养元素含量下降,土壤生物学活性减弱,但底层土壤熟化程度提高。为了维持幼林地土壤肥力,模式B、C应适当降低耕作强度,缩短间种年限,同时适当增加N和P肥使用量。模式A具有良好的改良土壤能力,是南方林区优良的杉木混农模式。

STUDIES ON THE SOIL FERTILITY IN THE AGROFORESTRY PATTERN OF CHINESE FIR WITH LITSEA CUBEBA AND CROPS

Studies on soil biological activities, chemical properties and structures ofsoil, constituents of pores and water status have been carried out in differentAgroforastry patterns, including Chinese fir-litsea cubeba (A), Chinese fir-litsea cubeba-Soybean (B), Chinese fir-litsea cubeba-Tobacco (C) and pureChinese fir forest. The results indicuted that the resultes showed that the top-soil structures of pattern B and C became poor, the content of soil nutrientsdeclined, soil biological activities decreased, but the ripening level of subsoilraised. In order to mantain the soil fertility of cultivated land, Pattern B andC would reduce the strength of cultivation, shoten the period of interplantingtimes, and appropriately increase the amount of the fertiliers of N and P Pa-ttern A had a good ability to modifing soil. Thus it would be a good agro-forestry pattern for Chinese fir in south forest areas of China.