生物土壤结皮对草原露天矿排土场生态恢复的影响

发布时间：2018-03-01 03:04

本文关键词： 生物土壤结皮伊敏露天矿土壤发育降水再分配植被群落演替　出处：《中国地质大学(北京)》2017年硕士论文　论文类型：学位论文

【摘要】：干旱半干旱草原区一直以来就是生态环境脆弱地区,随着露天煤矿开采,,典型草原区伊敏露天矿排土场上出现了与原地貌截然不同的生境——生长着大片的生物土壤结皮(BSCs),BSCs的生态功能对于解决草原区露天矿复垦表土不足、水资源短缺、适宜物种少这三大问题有重要的意义。本文通过生物土壤结皮调查、植被多样性调查以及土壤样品采集和降水模拟实验,分析了 BSCs对复垦土壤初期发育、降水再分配影响和与植被群落演替的关系,主要研究结果如下:1.排土场BSCs对复垦土壤初期发育影响明显。(1)对土壤质地和土壤容重的影响主要集中于0～5cm表土层。2mm～0.05mm范围内的颗粒是排土场BSCs形成和发育的物质基础,随着BSCs的拓殖和发育,粗砂粒含量减少、细砂粒和粗粉粒的含量在增高;藻结皮比苔藓结皮对土壤容重影响更为明显。(2)除了pH值,其他土壤发育化学指标受结皮影响且差异显著。有机质、水解性氮、速效磷、速效钾受结皮影响积累程度都可以达到土层20cm,全氮积累程度达到土层10cm;藻结皮对速效磷的积累能力高于苔藓结皮和地衣结皮。2.BSCs对表工具有显著的持水能力。(1)低降雨量(5mm)时,不同类型结皮的短期表土持水能力显著,但是较长时间内的持水能力存在差异,苔藓结皮持水能力大于其他两种结皮。(2)高降雨量(10mm)时,苔藓结皮短期和长期都有明显的持水能力。BSCs对降水拦截作用与其对土壤质地的影响共同改变了土壤水分的入渗。排土场复垦土壤表土持水能力和入渗、再分配过程的变化,形成了全新的土壤一植被系统水环境。3.随着BSCs盖度的增加,排土场植被功能群落重要值、物种多样性指数都呈现出不同的变化规律。(1) 一、二年生草本(AB)重要值逐渐减少,呈现负相关;多年生草本(PH)重要值和典型草原优势种(DS)先升后降;灌木、半灌木(SH)重要值呈现先降低后升高的变化趋势,存在明显的典型草原灌丛化。(2) Shannon-Wiener 多样性指数(H')、Simpson 多样性指数(D)、Patrick丰富度指数(Pa)、Pielou均匀度指数(Jp)呈现先上升后下降趋势,Patrick指数变化起伏更大,受结皮盖度影响更为明显,在人工扰动的露天矿排土场,BSCs成为植被演替的重要驱动因素之一。
[Abstract]:The arid and semi-arid grasslands have always been areas with fragile ecological environments. With the development of open pit coal mine, the ecological function of BSCS BSCs on the dump of Yimin opencast mine in typical grassland area is very different from the original landform, and the ecological function of BSCS BSCs can solve the shortage of reclaimed topsoil in open pit. It is of great significance that water resources are short and suitable species are few. Through the investigation of soil crust, vegetation diversity, soil sample collection and precipitation simulation, this paper analyzes the effect of BSCs on the initial development of reclaimed soil. The relationship between the influence of precipitation redistribution and the succession of vegetation community, The main results are as follows: (1) the effect of BSCs on the initial development of reclaimed soil is obvious.) the effect on soil texture and bulk density is mainly concentrated in the 0 ~ 5 cm surface layer of 0 ~ 5 cm surface layer. 2 mm ~ 0. 05 mm particles are the material basis for the formation and development of BSCs in the dump. With the colonization and development of BSCs, the content of coarse sand decreased, the content of fine sand and coarse silt increased, the effect of algal crust on soil bulk density was more obvious than that of moss crust. Other chemical indexes of soil development were affected by crusts and the differences were significant. Organic matter, hydrolytic nitrogen, available phosphorus, organic matter, hydrolysate nitrogen, available phosphorus, The accumulation of available potassium under the influence of crust can reach 20 cm in soil layer and 10 cm in total nitrogen, and the accumulation capacity of available phosphorus in algal crust is higher than that in moss crust and lichen crust. 2.BSCs have significant water holding capacity to surface tools. The water holding capacity of different types of crust was significant, but the water holding capacity of moss crust was higher than that of the other two types of crusts (10mm), but the water holding capacity of moss crust was higher than that of the other two types of crusts (10mm). Both short and long term moss crust has obvious water holding capacity. BSCs affect precipitation interception and soil texture together change the infiltration of soil water. With the increase of BSCs coverage, the important values of vegetation functional communities and the species diversity indices in the dump showed different variation patterns. One, the important values of the biennial herbaceous herbaceous plants gradually decreased with the increase of BSCs coverage. The important values of PHP and DSs of typical steppe increased first and then decreased, and the important values of shrub and subshrubs showed a tendency of decreasing first and then rising. There were obvious typical steppe thickets. 2) Shannon-Wiener diversity index, Shannon-Wiener diversity index, Patrick richness index, and Pao Pao Pielou evenness index (JpP) showed a trend of rising first, then decreasing. The variation of Shannon-Wiener index was more fluctuating, and was more obviously influenced by crust cover. BSCs have become one of the important driving factors of vegetation succession in artificial disturbed open pit dump.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD88;S812

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