Species diversity and stability of natural secondary communities with different cutting intensities

来源 :Journal of Forestry Research | 被引量 : 0次 | 上传用户:jch26
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Species diversity and stability of natural secondary communities in different layers with different cutting intensities 10 years later were investigated by calculating Marglef Richness index(R),Shannon-Wiener diversity index(H),Simpson diversity index(P),and Pielou Evenness index(J).Results show that the values of R,H and P among different layers are listed in a decreasing order:the shrub layer > the arbor layer > the herb layer,all the three indices values reach the maximum under medium selective cutting intensity after 10 years.The J value of the shrub layer shows a concave parabolic change with the increase in cutting intensity;it shows a linear increase for the arbor layer,whereas the J value of the herb layer shows an opposite change pattern.The values of R at different cutting intensities had high significant difference,but other indices had not significant difference.The stability of communities at different cutting intensities after 10 years is non-cutting> low selective cutting intensity > medium selective cutting intensity > high selective cutting intensity > extra-high intensity > clear cutting.The stability of communities at different cutting intensities after 10 years shows that the greater cutting intensities,the worse the stability is. Species diversity and stability of natural secondary communities in different layers with different cutting intensities 10 years later were investigated by calculating Marglef Richness index (R), Shannon-Wiener diversity index (H), Simpson diversity index (P), and Pielou Evenness index ( J) .Results show that the values ​​of R, H and P among different layers are listed in a decreasing order: the shrub layer> the arbor layer> the herb layer, all the three indices values ​​reach the maximum under medium selective cutting intensity after The J value of the shrub layer shows a concave parabolic change with the increase in cutting intensity; it shows a linear increase for the arbor layer, whereas the J value of the herb layer shows an opposite change pattern. The values ​​of R at different cutting intensities had high significant difference, but other indices had not significant difference. stability in communities at different cutting intensities after 10 years non-cutting> low selective cuttin g intensity> medium selective cutting intensity> high selective cutting intensity> extra-high intensity> clear cutting. stability of communities at different cutting intensities after 10 years shows that the greater cutting intensities, the worse the stability is.
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