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从凋落物和根系生物量角度对三峡库区不同年龄马尾松人工林土壤理化性质进行测定.结果表明:马尾松成熟林凋落物的年产量分别比近熟林、中龄林高19.4%和65.7%,凋落物现存量大小为成熟林>中龄林>近熟林,周转系数为近熟林(0.51)>成熟林(0.40)>中龄林(0.36);根系总生物量、活根及死根生物量均为中龄林最高、近熟林最低;中龄林土壤总孔隙度最大,容重最小;土壤有机质和总氮含量均是成熟林>中龄林>近熟林;近熟林土壤中硝态氮含量比重较大,中龄林和成熟林铵态氮含量比重较大.近熟林凋落物产量适中、周转系数最大,土壤养分最低;中龄林根系生物量和总孔隙度最大,土壤容重最小;成熟林土壤养分含量最高,根系生物量较低.根系生物量增加可以改善土壤的物理性质.
The soil physical and chemical properties of Pinus massoniana plantations at different ages in the Three Gorges Reservoir Area were measured from litter and root biomass.The results showed that the annual yield of litter in the mature Pinus massoniana plantations was 19.4% and 65.7% %, And the litter size was mature forest> middle-aged forest> near-mature forest, and the turnover coefficients were near mature forest (0.51)> mature forest (0.40)> middle aged forest The dead root biomass was the highest in the middle-aged forest and the lowest in the mature forest. The middle-aged forest had the highest total porosity and the lowest bulk density. The contents of soil organic matter and total nitrogen in mature forest> middle-aged forest> near-mature forest and near-mature forest The proportion of nitrate nitrogen in soil was higher than that in middle-aged forest and mature forest, and the litter yield of middle-aged and middle-aged forest was moderate, with the highest turnover coefficient and lowest soil nutrient content. The root biomass and total porosity The largest and the lowest soil bulk density.The content of soil nutrient in mature forest is the highest while the biomass in root system is lower.The increase of root biomass can improve the physical properties of soil.