缙云山不同植被类型林下土壤养分含量及物理性质研究

Investigation of Nutrients and Physical Properties of the Soil under Different Types of Forest Vegetation in Jinyun Mountain

采用野外调查与室内分析相结合的方法,对缙云山不同植被类型林下土壤养分含量和物理性质进行研究。结果表明:缙云山不同植被类型林下土壤随深度增加其pH值呈逐渐增大趋势,而有机质含量逐渐降低,有机碳含量呈现下降的趋势;土壤养分全量,除常绿阔叶林、针阔混交林、灌木林土壤养分全钾含量外,自上而下土壤养分全量逐渐降低;灌木林地的碱解氮和有效磷含量最高,常绿阔叶林地的速效钾含量最高。灌木林地、针阔混交林地和农地土壤质地为轻粘土,阔叶林地与楠竹林地土壤质地为中壤土,以A层为例,物理性粘粒(<0.01mm)含量依次为:农地(68.34%)>灌木林(62.38%)>针阔混交林(56.82%)>常绿阔叶林(51.78%)>楠竹林(24.52%)。土壤总孔隙度变动范围在56.82%～78.23%之间,非毛管孔隙度变动范围在11.31%～16.21%之间,非毛管孔隙度表现为:灌木林>针阔混交林>楠竹林>常绿阔叶林>农地。土壤微团聚体主要分布在0.01～0.5mm之间,以A层为例,团聚度大小为灌木林(57.45%)>农地(对照)(53.85%)>针阔混交林(50.16%)>常绿阔叶林(31.46%)>楠竹林地(6.4%),分散系数为灌木林(15.82%)<农地(对照)(21.02%)<针阔混交林(36.43%)<常绿阔叶林(42.74%)<楠竹林(43.17%)。研究结果可为森林土壤的合理利用,三峡库区的生态环境建设和保护提供一定的依据。

The nutrient content,physical properties of the soil under various plants communities in the Jinyun mountain were studied by means of field survey and laboratory analysis.The results showed that：（1） pH value increased with soil depth,while the amount of organic matter and soil organic carbon decreased gradually;Soil total nutrients,without total potassium in evergreen broadleaved forest,evergreen conifer and broad-leaved mixed forestand shrubs,also decreased with depth;（3）the greatest content of alkali-hydrolyzed nitrogen and available P was in shrubs,and rapidly available potassium in evergreen broadleaved forest.The soil texture is light clay in shrubs,mixed forest and cultivated land and loam in evergreen broadleaved forest,phyllostachys edulis forest,physical clay content（0.01 mm） appeared in the sequence of cultivated land（68.34%） shrubs（62.38%） mixed forest（56.82%） evergreen broadleaved forest（51.78%） phyllostachys edulis forest（24.52%）in A layers.The soil porosity was 56.82%~78.23%,and noncapillary porosity,appeared in the sequence of shrubs mixed forest phyllostachys edulis forest evergreen broadleaved forest cultivated land,was 11.31%~16.21%.Soil micro-aggregates mainly distributed in the layer of 0.01~0.5 mm,and the aggregation in A layers was made as follows： shrubs（57.45%）cultivated land（53.85%）mixed forest（50.16%）evergreen broadleaved forest（31.46%）phyllostachys edulis forest（6.4%）,and the order of the dispersion coefficient was shrubs（15.82%）cultivated land（21.02%）mixed forest（36.43%）evergreen broadleaved forest（42.74%）phyllostachys edulis forest（43.17%）.This paper provides theory for utilization of forest and eco-environment construction in three gorge reservoir area.