摘要
以黄土丘陵沟壑区的典型代表——安塞县为例,调查了退耕地植被恢复过程中的植被群落特征,分析了土壤速效N的分布特征、物种多样性的变化以及两者之间的相互作用关系,结果表明:土壤速效N的分布在剖面上具有明显的层次性,即从上到下依次降低;在不同植被群落中,土壤速效N含量在A、B层间的变化幅度大于B、C层次间,并且在植被恢复演替的前期,A、B两土层土壤速效N含量的变化相对较小,后期变化相对较大,而B、C两土层土壤速效N含量的变化则恰恰相反。0～60cm土层土壤速效N的平均含量在植被恢复的草本和乔木阶段,随植被的恢复演替而不断增加,在植被恢复的灌木阶段其含量变化则相反。相关分析表明,Menhinick指数和shannon-wiener指数与土壤速效N含量呈极显著正相关(P<0.01),simpson指数和Pielou指数与土壤速效N含量呈显著正相关(P<0.05)。因此,在对退耕地进行植被恢复时,应该保持和提高土壤速效N的含量,以保证植被恢复的进程。
Based on the typical hilly-gully regions on the Loess Plateau-Ansai county,the characteristics of plant communities during vegetation restoration were surveyed and the distribution characteristics of soil available N,the species diversity and their relationship were analysed.The results showed that soil available N gradually decreases from upper layers to under layers;the change ranges of the content of soil available N of different communities between layer A and layer B is bigger than that between layer B and layer C,and the changes of the content of soil available N in layer A and B is relatively smaller at the early stage of vegetation succession and is relatively bigger at the late stage of vegetation succession, the changes in layer B and C is just the contrary.The average content of soil available N of layer 0～60 cm gradually increases at the stages of herbage and arbour with vegetation restoration,and the change at the stage of shrub is just the contrary.There is most significant and positive correlations between soil available N and diversity index of shannon-wiener and richness index of Menhinick,and there is very significant and positive correlations between soil available N and diversity index of simpson and eveness index of Pielou.So in order to ensure actualization of vegetation restoration successfully,the content of soil available Nin abandoned lands during vegetation restoration should be maintained and improved.
出处
《水土保持研究》
CSCD
北大核心
2005年第1期13-16,21,共5页
Research of Soil and Water Conservation
基金
国家自然科学基金(40271074)
中国科学院"西部之光"项目(B22012900)
关键词
退耕地
土壤速效N
物种多样性
分布特征
相关性
黄土丘陵沟壑区
abandoned lands
soil available N
species diversity
distribution characteristics
correlation
loess hilly and gully regions
