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作 者:韩崇选[1] 杨学军[1] 王明春[1] 卜书海[1] 张宏利[1] 杨清娥[1]
机构地区:[1]西北农林科技大学林学院,陕西杨凌712100
出 处:《陕西师范大学学报(自然科学版)》2003年第S2期184-190,共7页Journal of Shaanxi Normal University:Natural Science Edition
基 金:国家"十五"科技攻关项目 ( 2 0 0 1BA50 9B0 7- 2 - 0 2 )
摘 要:在林地啮齿动物群落结构研究的基础上 ,探讨了群落优势种的概念和判别方法 ,认为林地群落优势种是在群落中数量大、密度相对稳定、分布比较均匀的广布种 ,并提出优势种指数的概念、计算公式和判别方法 .同时 ,以幼林生态系统为研究对象 ,提出了与林木危害程度相关的群落关键种的概念以及关键种指数的计算公式和判别标准 .指出群落关键种的实质是对林木造成严重危害的种群 ,其密度和组成比与林木的被害程度呈正相关 .用林木受害程度与各种群密度或组成比的相关系数作为关键种指数 .相关系数越大 。Base on the study community structure, studied the dominant species concept and the distinguish method, and thinking the dominant species in the community are azonal species that have a big quantity, opposite stability of density, distribute the even; and bring up the dominant species index concept, calculation the formula and distinguish the method. At the same time, with the large sapling forest ecosystem is for the research object, bring up the concept of key species that with related the degree of harm sapling, and the calculation formula of key species index and distinguish the standard. Point out the community key species is species that result in serious impaired forest, its density with the constitute ratio and the degree of harm sapling is related. The key species index is the correlation coefficient that the degree of harm sapling and the rodent species density or constitute related analysis. The correlation coefficient is more big, and the degree of key species is more high.
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