|
|
|
| Effect of disturbances on soil fertility of northeast mountain swamp |
| Fan Jinfeng,Man Xiuling |
| College of Forestry,Northeast Forestry University,150040,Harbin,China |
|
|
|
|
Abstract Using species diversity indices,including Shannon-Wiener index(H′),Simpson diversity index(D1),the probability of two successive randomly chosen individuals belonging to different species(P),Pielou's evenness index (Jsw),Margalef species richness(D2),the characteristics of species diversity in difference communities was studied by selecting sample sites in hilly areas of Xiaolangdi reservoir.The relationship between species diversity and habitat was analysed using statistical methods.The results showed that: 1)The species diversity and richness had significant correlation with community types.The diversity indices had complex relationship with succession period.2) Some species diversity indices,such as H′,P,Jsw and D1,were always associated with relatively high soil moisture.and others diversity indices H′ and D1 have positively correlation with soil organic matter,available N,available P,However,thickness of soil had a significantly positive correlation with H′,D1 and P.3) The biomass of shrubs and trees had a significantly correlated with H′.There are no relation between D1 and biomass of herbs.4) The vegetation restoration period was positively correlated with species diversity indices Jsw and H′,but not P,D1 and D2.The species numbers increased by six averagely during 10 years of vegetation restoration.5) H′ had significantly positive correlation with coverage and height of shrubs.Therefore,the diversity indices in some communities decreased with increasing of coverage and height of community. 6)There was a clear negative correlation between species richness indices and height and coverage of herbs,and no significant correlation with H′.
|
|
Received: 05 December 2006
|
|
|
|
|
null
|
|
null
|
|
|
|
