不同刈割制度对大针茅草原优势种功能性状及功能多样性的影响

发布时间：2018-08-17 08:54

【摘要】：功能多样性、功能性状对草地生态系统功能属性影响越来越重要。刈割是草地利用管理的重要措施之一。因此本文设置4种刈割制度(刈割次数),调查选取优势种的七个功能性状,计算功能丰富度、功能均匀度、功能离散度以及Rao二次熵函数四个指数,探讨不同刈割制度对内蒙古大针茅草原优势种的功能性状、功能多样性的影响以及功能多样性指数与初级生产力之间的关系。结论如下:(1)刈割显著增加了物种的均匀度指数和多样性指数、而对丰富度指数无显著影响。(2)不同频次的刈割干扰显著降低大针茅草原优势种的植株高度、叶面积、丛幅等功能性状值。(3)刈割制度并不影响植物群落的功能丰富度(FRic);功能均匀度指数(FEve)在一年割一次的刈割频率下,功能均匀度指数达到最高,资源利用均衡程度最高;功能离散度(FDiv)指数在割两年休一年的刈割制度处理下,达到最高值,生态位重叠效应最弱;Rao二次熵函数(一年割两次)Rao二次熵函数(割两年休一年),一年割两次的刈割制度的功能性状的相似程度低于割两年休一年的刈割制度,刈割频率的增加会降低物种的趋同程度;(4)功能丰富度和功能均匀度与初级生产力之间无显著相关性。Rao二次熵函数和功能离散度指数与初级生产力呈现显著相关性,植物种功能性状的相似度增强和生态位重叠效应减弱有助于提高群落的初级生产力。
[Abstract]:Functional diversity and functional traits are more and more important to grassland ecosystem functional attributes. Cutting is one of the important measures in grassland utilization management. Therefore, four cutting systems (cutting times) were set up in this paper to investigate the seven functional traits of dominant species, and to calculate the four indexes of functional richness, functional uniformity, functional dispersion and Rao quadratic entropy function. To study the effects of different cutting systems on functional traits, functional diversity and the relationship between functional diversity index and primary productivity of dominant species in Inner Mongolia. The results were as follows: (1) cutting significantly increased the evenness index and diversity index of species, but had no significant effect on richness index. (2) cutting interference of different frequency significantly reduced the plant height and leaf area of dominant species. (3) the mowing system had no effect on the functional richness of plant community (FRic); function evenness index (FEve) reached the highest at the cutting frequency once a year, and the resource utilization equilibrium degree was the highest. The (FDiv) index of functional dispersion reached the highest value under the cutting schedule of two years and one year. The weakest niche overlap effect is Rao quadratic entropy function (cut twice a year) Rao quadratic entropy function (cutting two years off a year). The similarity of functional characteristics of cutting system with two times a year is lower than that with two years cut off. (4) there was no significant correlation between functional richness and functional uniformity and primary productivity. Rao quadratic entropy function and functional dispersion index were significantly correlated with primary productivity. The enhancement of the similarity of functional traits and the weakening of niche overlap effect of plant species can improve the primary productivity of the community.
【学位授予单位】：内蒙古大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S812

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