贵阳市近郊不同人为干扰迹地土壤种子库研究

目的]对贵阳市边郊不同人为干扰迹地土壤种子库进行研究。方法]利用种子萌发试验,从土壤种子库数量、物种组成、物种多样性等方面,对贵阳市乌当区马背山喀斯特次生林不同干扰迹地(弃耕地、火烧地和碎石堆积地)土壤种子库进行研究。结果]土壤种子库中,弃耕地、火烧地和碎石堆积地的种子密度分别为7 919±616、2 791±350和4 204±372粒/m2,物种组成以演替早期阶段的草本植物为主。碎石堆积地土壤种子库的Margalef丰富度指数最大,火烧地最小;弃耕地土壤种子库的Shanon-Wiener多样性指数最大,火烧地最小;碎石堆积地的Pielou均匀度指数最大,弃耕地最小,表明火烧地土壤种子库的种子数量和种类组成最少,弃耕地优势种明显。弃耕地和火烧地土壤种子库的相似性较高。在0～15 cm土层内,弃耕地和火烧地土壤种子密度随土层深度的增加而减少,碎石堆积地则随土层深度的增加先减小后增大。结论]该研究为退化喀斯特植被的恢复与重建提供了理论参考。

Study on Soil Bank of Different Artificially Disturbed Lands in Suburban Area of Guiyang City

Objective] We aimed to study the soil bank of different artificially disturbed lands in suburban area of Guiyang City.Method] From the quantity,species composition,species diversity,etc.of soil seed bank,we analyzed the soil bank of different artificially disturbed lands(such as abandoned farmland,burned land and rubble-pile land) in karst secondary forest of Mabei Mountain,Wudang District,Guiyang City based on seed germination experiment.Result] In soil seed bank,the seed density of abandoned farmland,burned land and rubble-pile land was 7 919± 616,2 791±350 and 4 204±372 grain/m2 respectively,and herbaceous plant in early succession stage was the main species.In addition,rubble-pile land had the largest Margalef richness index of soil seed bank,while that of burned land was the smallest.For Shanon-Wiener diversity index of soil seed bank,it reached the maximum value in abandoned farmland and the minimum value in burned land.From Pielou evenness index of soil seed bank,rubble-pile land had the maximum value,while abandoned farmland had the minimum value.The results showed that the quantity of seeds and species in soil seed bank was the most in burned land,and dominant species of abandoned farmland was obvious.Besides,the composition of soil seed bank in abandoned farmland and burned land was more similar.In 0-15 cm soil layer,as the increase of soil depth,soil seed density reduced in abandoned farmland and burned land,but decreased firstly then rose in rubble-pile land.Conclusion] The research could provide theoretical references for the restoration and rebuilding of degenerate vegetation in karst areas.