【作者】 董强；

【导师】 李凯荣；

【作者基本信息】 西北农林科技大学 ， 水土保持与荒漠化防治， 2007， 硕士

【摘要】 本文以天然林区、靠近天然林的人工林和远离天然林区的人工林(油松和刺槐)为主要研究对象,采用样地调查的方法,研究和分析了淳化县三个不同地区的人工林群落的物种组成和多样性,并与天然灌、草进行了比较。得出以下主要结论:(1)三个地区所调查的27个群落样方中共记录植物87种,隶属于31科70属,其中菊科植物8属14种,豆科植物8属11种,蔷薇科植物12属13种,禾本科植物9属9种,这四科植物占所含属种数分别占总属数的52.8%和总种数的54.0%。(2)天然灌丛在邻近人工林修复中起着主要作用。天然林区的刺槐群落和油松群落中分别有植物19种和17种,其中灌木植物数量均为8种,靠近天然林区刺槐群落内有植物16种,灌木植物有8种,这与当地的天然灌丛中的灌木植物数量比较接近,而远离天然林区的人工林中缺乏灌木。(3)天然林区和靠近天然林区的人工林群落以高位芽植物(中高位芽、小高位芽和矮高位芽)和地面芽植物占优势,该现象反应这里夏季温热多雨以及较长的严冬气候的特点,同时也反应了人工林层次结构特点,而远离天然林区的人工林群落物种较少,没有优势生活型组成。天然林区的灌木群落以小高位芽植物占优势,地面芽植物次之;草地群落以地面芽植物占优势。(4)人工林群落的物种丰富度在不同地区表现出明显的差异,天然林区和靠近天然林区人工群落的科、属、种的丰富度高于远离天然林区的人工群落;同一地区人工林的物种丰富度表现出刺槐群落高于油松群落,这是由群落特征和生境不同造成的。人工林区的刺槐和油松混交林群落的物种丰富度高于其纯林群落。(5)天然林区和靠近天然林的不同植被群落的物种多样性Shannon-wiener指数和丰富度指数高于远离天然林区的植被群落。三个地区的人工林中,刺槐群落的Shannon-wiener指数和丰富度指数均高于油松群落,说明有利于其他物种的侵入和定居。不同层次的Shannon-wiener指数和丰富度指数在刺槐群落表现出:草本层>灌木层>乔木层,油松群落的表现出:灌木层>草本层>乔木层。不同群落或群落不同层次之间,Simpson指数(生态优势度指数)的变化趋势与物种丰富度基本是负相关关系。(6)三个地区人工林群落之间的相似性较高,人工林群落与灌木群落、草地群落由于生境的不同相似性表现出不同的差异,生境接近的群落相似性较高,共有物种较多;反之则共有物种较少。更多还原

【Abstract】 Choosing the plantations forest in natural forest, closing natural forest and the plantations forest of far away from the natural forest as the study object, employing the way of sample plot’s surrey, studying and analyzing the spieces composition and diversity of plantation forest in three different region in Chunhua county, and compared with natural bush and grassland .Come to the following conclusions:(1)There were 87 species in the 27 sampling blocks in three investigation regions. They belong to 70 gengeras, 31 families. There were 14 species ,8 gengera of Chrysanthemums; 8 genera, 11 species of Leguminous;12 genera, 13 species of Rosaceae;9 genera, 9 species of Gramineae. The plants of these four families account for 52.8% of total gengeras and 54.0% of total species.(2)There were 19 species in Locust community and 17 species in Chinese pine Community in area of natural forest, in which there were 8 shrubs in two communities respectively. There were 16 species in Locust Community of area closing to natural forest, 8 of them were shrubs. Which were similar to the natural shrub community. The plantations of far away from the natural forest were lack of shrub, which indicted that the shrub community play major role in the process of restoration of plantations.(3)The plant of phanerophytes(meso-phanerophyta、micro-phanerophyta and mano-phanerophyta) and hemicryptophyte of plantation forest communities in the natural forest area and closing natural forest area were dominant. The phenomenon show the climatic characteristics of hot and much rain in summer, very cold and long in winter .The phenomenon also reflects the structure characteristics of plantation hierarchy. There had few species in plantation forest communities which is far away from the natural forest. And there had no dominant plant of life-form in plantation forest communities . The plant of micro-phanerophyta is dominant in shrub community of natural forest, hemicryptophyte take the second place. The hemicryptophyte is dominant in grassland community. (4)Species richness of plantations community in different regions show significant differences. The number of families, genera and species in forest plantations communities of natural forest and closing to nature forest were higher than the forest plantations communities far away from the natural forest. And the species richness of Locust community show higher than Chinese pinus community in same place. The difference between Locust community and Chinese pinus community were decided by characteristics and habitats of communities. The species richness of community of Locust and Chinese pine mixed higher than its pure. community.(5)Shannon-wiener index of species diversity and richness index of communities in natural forest area and closing to natural forest areas are higher than these communities far away from nature forest areas. Shannon-wiener index of and richness index of Locust Community was higher than Chinese pinus in three regions. Which note that Locust Community was favor to the invasion and Settlement of other species. Shannon-wiener index and species richness index of different levels of community show difference. Considering locust Community:herb layer >shrub layer > tree layer,Considering Chinese pinus Community: shrub layer > herb layer > tree layer. There was negative correlation between Simpson index and species richness index.(6) Similarity index between plantations communities in these three regions has a higher comparability. And there were discrepancy of Similarity index between the forest plantations community and the natural shrub community by different habitats .The same phenomena can be found between the forest plantations community and the grassland community. The results indicated that the common species were much more between two communities which had similar habitats. Conversely, the common species very few in different habitats.更多还原