雷公山自然保护区不同植被类型土壤的肥力及碳含量

Soil Fertility and Carbon Content of Different Vegetation Types in Leigong Mountain Natural Reserve Area

为喀斯特森林植被恢复与喀斯特生态系统管理提供科学依据,根据喀斯特地区林地资源的实际情况,以贵州省雷公山自然保护区森林土壤为研究对象,在保证采样点具有典型性和代表性的基础上,通过野外调查与室内分析相结合的方法,对雷公山不同植被类型（灌草丛、常绿阔叶林、针阔混交林和暖性针叶林）林下土壤剖面（0～60 cm）的养分含量和颗粒态有机碳（POM-C）、黑碳进行了研究.结果表明：4种典型植被和农用地的土壤均呈较强的酸性,土壤pH值随深度的增加有增大趋势,各植被类型下土层0～ 15 cm的有机质和有效养分含量明显高于其他层,土层0～55 cm的养分含量逐渐减少.总体上灌草丛土壤的有效磷、速效钾、碱解氮含量较高,土壤氮、磷、钾含量受植被的影响很大,但土层越深受植被的影响越弱.不同植被类型下土壤中POM-C和黑碳含量均随剖面深度增加而下降.农用地土壤有机碳的稳定性明显高于森林土壤,灌草丛和农用地土壤中黑碳含量下降趋势一致并比较接近.

The nutrient content,POM-C content and black carbon content of forest soil with 0-60 cm depth of different vegetation types （scrub-grassland,evergreen broad-leaf forest,mixed broadleaf-conifer forest and warm coniferous forest） in Leigong Mountain Natural Reserve Area were determined by field investigation and lab analysis to provide the scientific basis for vegetation recovery and eco-system management in karst forest.The soil of four typical vegetations and farmland all are of strong acidity and the soil pH presents a rising trend with increase of soil depth.The organic matter and effective nutrient content of soils with 0-15 cm depth of different vegetation types is significantly higher than soils with other depth and the nutrient content of soils within 0-55 cm depth gradually decrease with depth increase.The soil available P,rapid available K and available nitrogen content of the scrub-grassland is the highest among four vegetation types.The soil N,P and K content is affected by vegetation types but the affecting ability decrease gradually with increase of soil depth.The soil POM-C and black carbon content of different vegetation types decrease with increase of profile depth.The stability of organic matter content of farmland is higher than forest soil obviously.The declining trend of black carbon content in soils of the scrub-grassland and farmland is no difference.