【作者】 林慧龙；

【导师】 刘荣堂；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2002， 硕士

【摘要】 本文主要从高寒地区三组份禾草混播草地群落的种内、种间竞争机制出发，建立了适合高寒地区三组份禾草混播草地群落种内、种间竞争机制的Lotka-Volterra竞争效应理论模型：讨论了对称与非对称情况下该理论模型解的有界性、全局稳定性和相空间中空间周期解的存在性，并对该理论模型所描述的竞争进行了计算机试验，模拟结果表明：试验所选的3种高寒地区三组份禾草混播草群表现为两种类型，即不稳定的群落：多叶老芒麦(Elymus nutans)+无芒雀麦(Bromus inermis)+垂穗披碱草(Clinelumus nutans)和垂穗披碱草(Clinelumus nutans)+多叶老芒麦(Elymus nutans)+扁穗冰草(Agropyron cristatum)，其竞争结局是：群落内多叶老芒麦和垂穗披碱草二者共同表现为优势种群，无芒雀麦或扁穗冰草与优势植物的竞争结果将导致其从群落中消失，多叶老芒麦和垂穗披碱草种群将能稳定共存；不稳定—稳定过渡群落：多叶老芒麦(Elymus nutans)+无芒雀麦(Bromus inermis)+扁穗冰草(Agropyron cristatum)，在没有多叶老芒麦种群的时候，无芒雀麦和扁穗冰草种群可以共存，但是如果多叶老芒麦种群加入无芒雀麦和扁穗冰草群落以后，将会导致无芒雀麦和扁穗冰草种群趋于绝灭。本研究从二组份种间竞争的经典Lotka-Volterra模型出发，针对高寒地区三组份禾草混播草地群落的种内、种间竞争的特点，理论模型的3个前提条件是可以普遍接受的基本假设，因此理论模型具有一定的普遍性，对理论模型所进行的定性与稳定性分析结果表明，这种方法可初步地对竞争作用及其结局做进一步的分析和预测，更重要的是计算机模拟试验所得到的模型(5)、(6)、(7)及其分析结果，与多年观测的试验数据、结果基本相吻合，所以本项研究方式、方法具有一定的可行性，该项结果对科学建植人工草地具有一定的指导意义，且本研究对三组份禾草混播草地群落竞争效应模型的进一步改进和生态学研究植物竞争生长关系提供了新的思路。更多还原

【Abstract】 Based on specific and interspecific competition mechanism in Mixed Grassland of Cultivated Perennial Grass in Alpine Region of Qinghai-Tibetan Plateau of China,establishing, a class of Autonomos three populations Lotka-Volterrathe competition Model is established:It’s shown that the system can be made persistence under some appropriate conditions.Moreover,sufficient conditions that guarantee the existence of a unque positive periodic solution which is globally asympototic are derived. In order to find the ideal ways to maintain Mixed Grassland of Cultivated Perennial Grass stability, from May, 1998 to Octobr of 2002, this study was conducted at the Jingqianghe Alpine Grassland Station of Gansu Agricultural University, which is located in Tianzhu County, 3000m ASL of altitude (with -0.1 癈 of annual temperature and 416mm of precipitin annually).According to the experiment data, computer simulation models were established. The results indicate: All the communities of grass hi this study can be assorted into 2 groups according to their compatible abilities, namely , the unstable communities, including Elymns nutans + Bromus inermis + Clinelumus nutans, Clinelumus nutans + Elymus nutans + Agropyron cristatum, and the transition community between stable and unstable communities, Bromus inermis + Elymus nutans + Agropyron cristatum.The study provides a new approach to deal with the further improvement of interspecies competition models of the Mixed Grassland of Cultivated Perennial Grass in Alpine Region of Qinghai-Tibetan Plateau and the Mixed Grassland competition-growth relationship ecological study.更多还原