红花尔基草原-森林生态系统边缘效应对夏季鸟类群落结构影响

2005年6月和2006年7月,对红花尔基草原—森林过渡带鸟类群落结构进行了调查研究,共调查到鸟类6目13科25种。其中:鸦科(Corvidae)、鹀科(Emberizidae)、鹡鸰科(Motacillidae)的鸟类占观察鸟类总数的69.34%。树鹨(Anthus hodgsoni)、小嘴乌鸦(Corvus corone)、山斑鸠(Streptopelia orientalis)、沙即鸟(Oenanthe isabellina)、大嘴乌鸦(Corvus macrorhynchos)、白头鹀(Emberiza leucocephala)为本地区的优势鸟类,占观察鸟总数的72.99%。3种边缘类型生境鸟类多样性调查结果显示:灌木草原—樟子松林、白桦针阔混交林生境鸟类物种数是18种,多样性指数为2.4245;草甸草原—天然樟子松成熟林鸟类物种数是14种,多样性指数为2.2348;草甸草原—樟子松人工林鸟类物种数为11种,多样性指数为1.9485。但是树龄长的草甸草原—樟子松成熟林生境内鸟类群落的均匀度最高,为0.8388;草甸草原—樟子松人工林生境多样性指数和均匀度都显示最低,分别是1.9485、0.7841。对不同边缘距离鸟类多样性研究结果显示:在边缘50m的范围内,3种边缘类型鸟类群落多样性指数都显示最高。随着边缘距离的加大,鸟类群落多样性指数呈下降趋势,灌木草原—樟子松林、白桦针阔混交林生境下降趋势最为明显,鸟类群落显示出显著的边缘效应。

Edge Effect on Avian Community Structure in Steppe-Forest Ecosystem of Honghuaerji in Summer

A survey of bird community structure of Honghuaerji was conducted during summer periods in June, 2005 and July, 2006, and a total of 25 bird species belonging to 6 orders and 13 families were recorded. Bird species of family Corvidae, Emberizidae and Motacillidae account for 69.34 percent of the total. The dominant species are Anthus hodgsoni, Corvus corone, Emberiza leucocephala, Streptopelia orientalis, Oenanthe isabellina and Corvus macrorhynchos, accounting for 72.99 percent of the total. Results of species diversity of bird community in different edge habitats manifest that there are 18 species of birds in the edge habitat between the shrub-steppe and Pinus sylvestris var. mongolica and Betula platyphylla coniferous and broad-leaved mixed forest (denoted by SPB), and its diversity index is the highest (2.424 5); there are 14 bird species in the edge habitat between the meadow-steppe and Pinus sylvestris var. mongolica natural mature forest (denoted by MPN), and its diversity index is 2.2348; there are 11 bird species in the edge habitat between the meadow-steppe and P. sylvestris var. mongolica artificial forest (denoted by MPA), and its diversity index is the lowest (1.948 5). However the SPB has the highest evenness index of bird community (0.838 8), and the diversity index and evenness index in MPA are the lowest (1.948 5 and 0.784 1). Within the edge distance of 50 m, the bird species diversity of the three types of edge habitats is the highest. The diversity index of bird community decreases with edge distance increasing, and the declining trend of SPB is obvious, which indicates a remarkable edge effect in bird community.