半干旱黄土丘陵区不同土地利用类型植物物种多样性研究

【目的】为了更好地利用半干旱黄土丘陵区的土地资源,促进该区域植被恢复,提高生物多样性,使区域生态环境有所改善。【方法】以半干旱黄土丘陵区龙滩流域的植被为研究对象,对该流域11种典型的土地利用类型(2种农地、自然荒草地、人工牧草地、撂荒草地、灌木林地、5种乔木林地)的植被物种组成和多样性进行了调查研究。【结果】流域内共调查到种子植物56科166属254种,其中裸子植物门3科7属13种,占流域总科、总属、总种的5.36%、4.22%、5.12%;被子植物门53科159属241种,占流域总科、总属、总种的94.64%、98.78%、94.88%。在被子植物门中,双子叶植物纲有50科134属205种,单子叶植物纲有3科25属36种,两纲物种分别占流域总种数的80.71%和14.17%,占该门物种总种数的85.06%和14.94%。不同土地利用类型植被多样性分析结果表明,物种丰富度表现为农地物种丰富度低,人工牧草地、撂荒草地和灌木柠条林地居中,乔木林地(山杏、山毛桃、油松、侧柏、青杨)和天然荒草地高;物种多样性表现为马铃薯农地的物种多样性低,覆膜农地、人工牧草地、撂荒草地及灌木柠条林地居中,自然荒草地和乔木林地比较高;物种均匀度表现为农地、撂荒草地、人工牧草地及灌木柠条林地的均匀度高,自然荒草地居中,乔木林地低。【结论】不同土地利用方式和植被演替恢复时间差异是产生植被多样性差异的基础,也是该区域植被恢复和物种多样性保护需要考虑的重要要素。

Plant diversity of different land utilization types in semiarid loess hilly area

【Objective】In order to make better use of land resources in semi-arid loess hilly region,promote vegetation restoration,improve biodiversity and improve regional ecological environment.【Method】11 typical land use types(2 kinds of farmland and natural weeds)in Longtan watershed of semi-arid loess hilly region were studied.【Result】The species composition and diversity of vegetation in land,artificial grassland,abandoned grassland,shrub forest land and five kinds of arbor forest land were investigated:254 species of 166 genera from 56 families of seed plant were investigated in the basin,among them 13 species of 7 genera from 3 families were gymnosperms,accounting for 5.36%,4.22%and 5.12%of the total families,genera and species in the basin;the other 241 species belonging to 159 genera in 53 families were angiosperms,accounting for 94.64%,98.78%and 94.88%of the total families,genera and species in the basin.Among angiosperms,there are 205 species of 134 genera from 50 families for dicotyledons and 36 species of 25 genera from 3 families for monocotyledons,both species were respectively accounted for 80.71%and 14.17%of the total species in the basin,85.06%and 14.94%of the total species in the phylum.The results of plant species diversity analysis of different land types indicated that the species richness was low in agricultural land,medium in artificial grassland,abandoned cropland and shrub land of Caragana korshinskii,but high in natural grassland and the five kinds of arbor forestland(Armeniaca sibirica,Amygdalus davidiana,Pinus tabuliformis,Platycladus orientalis,Populus cathayana);The diversity of species behaved as low in Solanum tuberosum cropland,medium in mulch cropland,artificial grassland,abandoned cropland and C.korshinskii shrub land,high in natural grassland and arbor woodland;The species evenness was different from its richness and diversity,it is low in arbor woodland,medium in natural grassland,but high in cultivated cropland,abandoned cropland,artificial grassland and shrub land of C.korshinskii.【Conclusion】The study indicated the difference of land use patterns and different duration of vegetation succession and recovery is the basis for the difference of vegetation diversity,so it is important to consider the land use patterns and vegetation succession and recovery duration for the vegetation restoration and species diversity protection in this region.