【摘要】 以集约和粗放经营的毛竹(Phyllostachys heterocycla‘Pubescens’)林为研究对象,探讨了春季毛竹林集约经营后土壤有机碳的变化。结果表明:(1)集约经营后毛竹林0-10和10-20cm土层土壤总有机碳含量分别下降了7.01%和18.90%,易氧化碳含量分别下降了31.22%和46.03%,0-20cm土层轻组有机质含量下降了19.87%。(2)两种毛竹林的土壤有机碳含量在剖面上整体上均随土层深度的增加而呈下降趋势,但下降幅度不同。粗放经营的毛竹林土壤易氧化碳的剖面特征与总有机碳相似,而集约经营的毛竹林存在明显差异。轻组有机质具有表聚性,主要分布在土壤表层(0-20cm)。(3)土壤总有机碳、易氧化碳、轻组有机质与土壤养分之间的相关性均达到极显著水平(p<0.01),总有机碳与速效磷显著相关(p<0.05)。(4)集约经营后,毛竹林0-10cm土层土壤易氧化碳的碳素有效率和土壤碳库活度分别下降了26.01%和50.52%,差异显著(p<0.05);10-20cm土层分别下降了35.51%和54.41%。因此,施加适当配比的有机肥和无机肥,有利于土壤中各种有机碳的积累,也可改善土壤的生物化学活性。更多还原

【Abstract】 Aims Our objective was to determine the effects of intensive cultivation on soil organic carbon(SOC) in bam-boo(Phyllostachys heterocycla ’Pubescens’) forests.Methods We used the reference land unit method and collected soil samples in intensively and extensively managed bamboo forests in the spring.Important findings Under intensive management,total organic carbon(TOC) decreased by 7.01% and 18.90% and readily oxidized carbon(ROC) decreased by 31.22% and 46.03% in 0-10 and 10-20 cm soil layers,respec-tively.Also,light fraction organic matter(LFOM) decreased 19.87% in the 0-20 cm soil layer.Soil organic car-bon under the two types of management decreased with increasing soil depth,but the ranges of decrease were dif-ferent.The vertical distribution of ROC under extensive management paralleled that of TOC,while both were different under intensive management.LFOM tended to accumulate in surface layers(0-20 cm).TOC,ROC and LFOM were strongly correlated with soil nutrients(p < 0.01),and TOC was significantly related to available P(p < 0.05).After intensive management,the percentage of ROC to TOC and activity of carbon pool significantly dropped by 26.01% and 50.52%(p < 0.05),respectively,in the 0-10 cm soil layer and dropped by 35.51% and 54.41% respectively in the 10-20 cm soil layer.Therefore,a mixture of organic and inorganic manures with the proper ratio should be applied to promote SOC and improve biological and chemical soil activity.更多还原