玛曲高寒沙化草地生态位特征及其施肥改良研究  

Research on characteristics of plant niche and effects of fertilization on plant productivity in a Maqu Alpine desertified meadow

作　　者：王鹤龄[1,2] 牛俊义[1,3] 郑华平 陈子萱[1] 

机构地区：[1]甘肃农业大学农学院,甘肃兰州730070 [2]中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室中国气象局干旱气候变化重点开放实验室,甘肃兰州730020 [3]酒泉职业技术学院,甘肃酒泉735000 [4]甘肃省科学技术厅,甘肃兰州730000

出　　处：《草业学报》2008年第6期18-24,共7页Acta Prataculturae Sinica

基　　金：甘肃省科技攻关项目(2GS052-A41-007-03);科技部科研院所社会公益研究专项(2005DIB3J100);甘肃省自然基金(3ZS061-A25-010)资助

摘　　要：为高寒沙化草地治理提供理论依据,本研究分析了玛曲高寒沙化草地植物群落特征,探讨施肥对物种多样性和生物量的影响。结果表明,异针茅为玛曲当前高寒沙化草地的优势种。生态位宽度最大的是亚优势种高山唐松草和乳浆大戟,而优势种异针茅的生态位宽度仅为0.941。在沙化草地植物群落中,优势种并不具有最强的适应能力和竞争力且地位不稳定。生态位宽度大的物种之间具有大的生态位重叠值,其中高山唐松草和乳浆大戟种群生态位重叠值最大,它们与其他种群之间的竞争也较强,高寒沙化草地的演替方向将是杂类草取代禾草的优势地位。施肥可增加高寒沙化草地物种丰富度,其中氮磷配施和氮磷有机肥配施分别比对照的丰富度提高42.9%和44.7%。氮、磷和有机肥混施后植物群落的Simpson指数和Shannon-Weiner指数与对照之间达显著或极显著性差异,施氮磷肥后植物群落Pielou均匀度指数也与对照之间达极显著差异;采用氮、磷和有机肥混施的方案可最大限度的增加沙化草地的地上生物量,比对照地上生物量增加2.5倍。从生物多样性和生物量增加综合考虑,氮、磷和有机肥混施为高寒沙化草地施肥的最佳处理。The characteristics of niche breadth and niche overlap of 20 species and the effects of fertilization on productivity in Maqu Alpine desertified meadow was studied. The dominant species was Stipa aliena and the species with the largest Niche breadth were Thalictrum alpinum and Euphorbia esula. The niche breadth of the dominant species was only 0. 941 thus it was not the strongest and most competitive population, so the positions of communities and community structure are unstable. This results in further degradation of the alpine desertified meadow. Fertilization can increase species richness and vegetation height. Compared to the control, treatment with N, P and with N, P and organic manure increased species richness 42.9 % and 44.7% respectively. The Simpson index, Shannon--Weiner index and Pielou evenness index were all improved by the different types of fertilizers. Application of N, P and organic manure significantly improved the aboveground biomass. Of all the fertilizer treatments, N, P and organic manure maximized the improvement of the aboveground biomass which increased by 2.5 times compared with the control. Consideration of plant diversity and productivity showed that application of N, P and organic manure was the best treatment for plant diversity and productivity in the Maqu Alpine desertified meadow.

关 键 词：高寒沙化草地 生态位 施肥组合 植物多样性 生物量 

分 类 号：S812.8[农业科学—草业科学] S147.2[农业科学—畜牧学]