半干旱区封育措施下植物生态位研究

运用Levins生态位宽度指数及Pianka生态位重叠指数,对宁夏盐池封育措施下老封育区、新封育区和对照区的植物生态位宽度及生态位重叠度进行计量。结果表明,封育措施对沙化草地植被的恢复具有明显的促进作用;老封育区内阿尔泰狗哇花、刺沙蓬、隐子草和狗尾草的生态位宽度最大,是该区的优势种;新封育区和对照区都是黑沙蒿和丝叶山苦荬的生态位宽度最大。生态位重叠度的分析结果表明,生态位宽度与生态位重叠度之间并不存在直接的线性关系。

Study on Plant Niche under Enclosed Measures in Semi-arid Areas

Plant niche breadth and niche over-lapping under enclosed measures in old enclosed region,new enclosed region and contrast region in Yanchi county of Ningxia were measured by means of Levins niche breadth and Pianka niche overlapping indexes.The results showed that enclosed measures had significant promoting effect on the recovery of desertification grassland vegetation.The plants with the largest niche breadth in old enclosed region were Heteropappus altaicus(Willd.) Novopokr.,S.ruthenica Iljin,Cleistogenes Keng and Setaria viridis(L.) Beauv..They were the dominant species of this area.The plants with the largest niche breadth in new enclosed region and contrast region were Artemisia ordosica Krasch.,Lxeris chinensisvar.graminifolia(Ledeb.)H.C.Fu.The results of niche overlapping analysis also showed that the niche breadth and niche overlapping did not have a direct linear relation.