围封年限对荒漠草原群落结构及物种多样性的影响  

Influence of Enclosed Period on Community Structure and Species Diversity of Desert Steppe

作　　者：潘笑笑 刘秉儒[2,3] 牛宋芳 王利娟 韩丛丛[2,3] 

机构地区：[1]宁夏大学农学院,宁夏银川750021 [2]宁夏大学西北土地退化与生态恢复国家重点实验室培育基地,宁夏银川750021 [3]宁夏大学西北退化生态系统恢复与重建教育部重点实验室,宁夏银川750021

出　　处：《贵州农业科学》2018年第7期95-99,共5页Guizhou Agricultural Sciences

基　　金：宁夏自然科学基金项目“荒漠草原人工灌木林地下水埋深生长季变化规律及其与降水量关系”(NZ15001)

摘　　要：为探明不同围封年限对荒漠草原群落结构及物种多样性的影响,揭示荒漠草原群落及植被随围封年限的变化规律,选取宁夏盐池县未围封、围封5年、8年、12年和15年的荒漠草原天然草地为研究对象,比较其群落组成、地上植被特征及物种多样性指数。结果表明:随着围封年限的增加,物种所属的科种数目呈倒V型,围封第5年达最多;一年生和多年生草本植物随围封年限的增加呈递减趋势;围封样地植被的盖度、高度及地上生物量均大于未围封样地,各围封年限之间地上生物量差异均显著(P<0.05);未围封样地与围封8年、12年的Simpson多样性指数间无差异显著性,与围封5年和15年的草地间差异显著(P<0.05)。围封对退化的草地生态系统有一定的改善作用,但有草地灌丛化的趋势,不利于草场发展,初次封育5年较合理,长期封育15年较适宜。To explore the influence of enclosed period on community structure and species diversity of desert steppe, and the change law of community and vegetation in enclosed period,the authors select five plots that were unenclosed, enclosed for 5 years, 8 years, 12 years, 15 years in the desert steppe grassland as the research object, and compare their community composition, vegetation characteristics and species diversity index. Results： Number of species presents as an inverted ＂V＂ type with enclosed years, and reaches the peak at the fifth year; Number of annual and perennial herbaceous plants decrease with enclosed years; The coverage degree, height and aboveground biomass of enclosed sites are all higher than unenclosed sites. Aboveground biomass varies significantly among different enclosed years（ P 〈0.05）; Simpson diversity index of unenclosed sites has no significant difference with that enclosed for 8 years and 12 years, but significantly different with that enclosed for 5 years and 15 years（ P 〈0.05）. The enclosure has a protective effect on degraded grassland ecosystem, but it tends to become shrub. It is not conducive to the development of grassland, enclosed for 5 years or 15 years is more appropriate.

关 键 词：荒漠草原 围封 群落结构 物种多样性 

分 类 号：S283[农业科学—农业水土工程]