低强度地表火对马尾松次生林物种多样性的影响

采用样地调查法对低强度地表火干扰样地马尾松次生林的物种多样性进行了调查.结果表明:对照样地马尾松林乔木层的重要值为68.1,而火干扰样地马尾松的重要值下降到51.4;火干扰样地内物种和植物个体数目均高出对照样地,分别为对照样地的118%和108%;对照样地内Gleason丰富度指数、Shannon-Wiener指数、Simpson指数、Pielou均匀度分别为3.01、11.21、10.30、0.74,火干扰样地的分别为12.13、5.61、26.13、0.84;火干扰样地各层和所有植物的均匀度值显著提高,乔木层、灌木层、草本层的均匀度分别由0.71、0.83、0.55提高到0.81、0.89、0.72.火干扰样地中的灌木层马尾松个体数量增加,说明低强度地表火可以增加马尾松林生物多样性和促进马尾松林的更新.

Species Diversity Response to Fire Disturbance of Pinus massoniana

Forest fire is one of the factors threatening species diversity.This paper investigates over the change of species diversity of Pinus massoniana secondary plantation caused by its low-intensity surface fire.Results show that its important value in contrast stand(CS) is 68.1 while that in fire disturbance stand (FS) drops to 51.4;that there are 74 kinds and 1078 plants in CS but the number of kinds and plants in FS increases respectively 18% and 8%;that the Gleason(IGL) index,the Shannon-Wiener(ISW)index,the Simpson(ISP) index and the Pielou(J)of CS are 10.30,3.01,11.21 and 0.74 but the index of FS is respectively 12.13,5.61,26.13 and 0.84;and that the value of evenness,of every layer and all the plants in FS,is enhanced respectively from 0.71(for crown canopy),0.83(for shrub layer) and 0.55(herb layer) to 0.81,0.89 and 0.72.All these indicate that the number of individual plants in FS is higher than that in CS;thus,low-intensity surface fire may increase the biodiversity and promote the renewing of Pinus massoniana forest.