衡阳紫色土丘陵坡地自然恢复过程中植被与土壤特性变化

Variations of vegetation and soil properties in the process of natural re-vegetation on sloping-land with purple soils in Hengyang

采用＂空间序列代替时间序列＂的方法,对衡阳紫色土丘陵坡地植被自然恢复过程中植被与土壤特性的变化进行研究.结果表明：（1）随着植被恢复的进行,土壤种子库密度显著增加（P〈0.05）,土壤种子库的Patrick丰富度指数（R）和Shannon-Wiener多样性指数（H）显著提高（P〈0.05）,土壤种子库的Simpson多样性指数（D）和Pielou均匀度指数（E）显著降低（P〈0.05）;（2）随着植被恢复的进行,植物的群落结构发生明显的改变,植被密度显著增加（P〈0.05）,植物的Patrick丰富度指数（R）、Simpson多样性指数（D）、Shannon-Wiener多样性指数（H）和Pielou均匀度指数（E）的大小顺序均为：恢复阶段（Ⅲ）〉恢复阶段（Ⅳ）〉恢复阶段（Ⅱ）〉恢复阶段（Ⅰ）（P〈0.05）;（3）随着植被恢复的进行,0～10 cm、10～20 cm和20～30 cm各土层的土壤含水量、土壤有机质、全氮、碱解氮和速效磷发生明显的变化（P〈0.05）,速效钾含量的变化不明显（P〉0.05）,其变化范围为259.55～368.32 mg·kg-1.研究表明：衡阳紫色土丘陵坡地植被自然恢复有利于改善植被与土壤特性.表4,参21.

Variations of vegetation and soil properties in the process of natural re-vegetation on sloping-land with purple soils in Hengyang were studied with the method of space for time. The results showed that：（ 1） In the process of natural re-vegetation,the density of soil seed bank significantly increased（ P〈0. 05）,R（ Patrick richness index） and H（ Shannon-Wiener index） of soil seed bank significantly increased（ P〈0. 05）,D（ Simpson index） and E（ Pielou evenness index） of soil seed bank significantly decreased（ P〈0. 05）;（ 2） There was obvious changes of re-vegetation structure,plant density significantly increased in the process of natural re-vegetation（ P〈0. 05）,and R,D,H,E were followed the order as re-vegetation stage（ Ⅲ re-vegetation stage（ Ⅳ） re-vegetation stage（ Ⅱ） re-vegetation stage（ Ⅰ）（ P〈0. 05）;（ 3） There were obvious changes of the content of SWC（ Soil water content）,SOM（ Soil organic matter）,TN（ Total nitrogen）,AN（ Alkali-hydrolyzed nitrogen） and AP（ Available phosphorus） in 0 ～ 10 cm,10 ～ 20 cm and 20 ～ 30 cm soil layers in the process of re-vegetation（ P〈0. 05）,but the content of AK（ Available potassium） was not obvious（ P〈0. 05）,varying in the range of259. 55 ～ 368. 32 mg. kg-1. All the results indicated the natural re-vegetation could improve vegetation and soil properties on sloping-land with purple soils. 4tabs.,21 refs.