桂东南主要造林树种林下乔灌草多样性研究

Study on the Diversity of Understory Trees,Shrubs and Grasses of Main Afforestation Tree Species in Southeast Guangxi

调查研究了博白林场马尾松、湿地松、杉木和巨尾桉4种纯林林下乔灌草多样性及其生物多样性。结果显示:4种纯林林分中的乔木、灌木、草本的Menhinick丰富度指数分别为0.452~1.387,0.906~1.17,0.409~0.905;Simpson多样性指数分别为0.4~0.81,0.82~0.86,0.51~0.92;Shannon-wiener多样性指数分别为1.05~2.79,2.96~3.33,1.44~4.02;均匀度指数分别为0.61~0.9,0.87~0.92,0.58~0.95。分析结果表明:随着海拔的升高,纯林乔木多样性指数呈先增大后减小,灌木多样性指数先增大后减小,草本多样性指数先减小后增加;随着坡度增大,乔木多样性指数呈先增大后减小,草本先减小后增大,灌木Shannon-wiener多样性指数先增大后减小,而Simpson多样性指数、均匀度指数基本保持不变,Menhinick丰富度指数先增大后减小;随着郁闭度增大,乔木多样性先增大后减小,灌木和草本的多样性则呈先减小后增大。

This paper studied the relationship of the diversity of arbors,shrubs,grasses and their biodiversity and their impact factors in 4 pure forests(Pinus massoniana,Pinus elliottii,Cunninghamia lanceolata and Eucalyptus grandis x urophyll).The result shows that the Menhinick richness indexes of trees,shrubs and herbs in the four stands were 0.452~1.387,0.906~1.17 and 0.409~0.905,respectively.The Simpson diversity indexes were 0.4~0.81,0.82~0.86 and 0.51~0.92,respectively.The diversity indexes of Shannon-Wiener were 1.05~2.79,2.96~3.33 and 1.44~4.02,respectively.The indexes of uniformity were 0.61~0.9,0.87~0.92 and 0.58~0.95,respectively.With the elevation increasing,the tree diversity index first increased and then decreased;the shrub diversity index first increased and then decreased,and the herb diversity index first decreased and then increased.With the increase of slope,the diversity index of trees first increased and then decreased;herb first decreased and then increased;shrub Shannon-Wiener diversity index first increased and then decreased;Simpson diversity index and evenness index remained basically unchanged;Menhinick richness index first increased and then decreased.With the increase of canopy density,tree diversity first increased and then decreased,and shrub and herb first decreased and then increased.