长期施肥对黄土区苜蓿草地群落特征及其多样性的影响  

Effects of Long-term Fertilization on Structure and Species Diversity of Alfalfa Grassland Communities in the Loess Plateau

作　　者：蔡志风[1] 郝明德[1,2] 吴振海[3] 史培[1] 王缠军[1] 普琼[1] 

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]西北农林科技大学生命科学学院,陕西杨凌7121001

出　　处：《西北农业学报》2010年第10期86-90,共5页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家重点基础研究发展计划项目(2009CB118604和2005CB121101);国家科技支撑计划项目(2006BAD05B07和2006BAD15B01-03);中科院知识创新方向性项目(kzcx2-yw-424-3)

摘　　要：利用长期定位试验,对不同施肥条件及粮草轮作不同生长年限的苜蓿草地群落特征和多样性变化进行了研究。结果表明,不同施肥处理下连作苜蓿草地群落物种多样性指数变化不显著,苜蓿种群重要值明显增加,且单施P肥比NPM配施增幅大,施P肥可维持群落较高的多样性,延缓苜蓿草地衰退时期和延长其高产期年限;轮作苜蓿草地物种丰富度和多样性指数随苜蓿生长年限的增加均呈先降后升的趋势,均匀度指数变化不显著,苜蓿重要值表现出先增加后降低的趋势,苜蓿生长的第2 a,其种群重要值最大,群落物种多样性最低,后因杂草入侵和养分匮缺,人工草地呈现出明显退化态势,中耕除草与施肥可延长其使用寿命。The changes of the characteristics and biodiversity of alfalfa grasslands communities under different fertilizations and different growth age alfalfa grasslands communities in cropping wheat-alfalfa rotation system were analyzed,respectively,from the trial of long-term located fertilization.The results were as follows,.the species diversity indexes of the continuous cropping alfalfa grassland under different fertilizer treatments did not significantly differ,but the importance value of alfalfa populations obviously increased,and the increase was greater in the P manure plot than N,P plus organic manure plot,P manure could maintain high species diversity of communities,postpone the degraded time and prolong the years of high productivity of the alfalfa grassland;the variation trends in species richness and Shannon-Weiner index of the alfalfa rotation grassland with the increase of alfalfa growth years were consistent,which decreased at first and increased subsequently,the change of Pielou evenness index was not significant,a change trend in important value of alfalfa populations raised at the beginning and dropped afterwards,the important value of alfalfa populations was greatest,while species diversity was lowest on the second year of alfalfa growth,then artificial grassland began to degrade from invasion of forbs and deficiency of nutrients,cultivation and fertilization can prolong the utilized life-span of artificial grassland to some extent.

关 键 词：黄土区 长期定位施肥 苜蓿草地 群落特征 多样性 

分 类 号：S541.9[农业科学—作物学]