Research On Community Structure Of Typical Forests In Nanshan Forest Park

Biodiversity is the foundation of human survival and social sustainable development, withbooming development of the tourism industry which forest as its main body, forest vegetation in foresttourism destination and its habitat are under serious threat.Nanshan forest park in Jiyuan city of Henan province belongs to Taihang low hills mountain,Robinia pseudoacacia, Platycladus orientalis, Quercus variabilis are widely distributed in the park andhave obvious typical and representative in plant community types. The research of plant communitystructure not only contribute to clarify plant community species composition, dynamic function,etc.,also reflect the relationship between community and environmental factors, and thus provides thetheory basis for production practice of ecological function improving and reasonable management ofplantation which interfere with the strong artificial disturbance.The species component, community structure and species diversity of three typical forestcommunities, Platycladus orientalis, Quercus variabilis and Robinia pseudoacacia, were studied bysampling method in Nanshan forest park in Jiyuan city of Henan province in June and July2009, July2011. The results showed that:(1) There were99species of plants which belong to81genera42families in survey sample.There were50species of plants which belong to42genera29families in Platycladus orientalis. Therewere40species of plants which belong to36genera27families in Quercus variabilis. There were64species of plants which belong to57genera33families in Robinia pseudoacacia.(2) The results showed that structures of the sample communities were simple. The tree layer, theshrub layer and the herb layer were obviously stratified. The tree layer height was between3~15m, theshrub layer height was between1~3m and the herb layer height was under1m, generally between10~30cm. The diameter structure analysis showed that the average diameter at breast height (DBH) anddiameter class distribution of Quercus variabilis and Robinia pseudoacacia communities increases withforest age.(3) The edificators of tree species are the advantage tree species of tree layer in three kinds ofcommunity. The co-edificators of Platycladus orientalis and Quercus variabilis community was Robiniapseudoacacia. The co-edificators of Robinia pseudoacacia community was Diospyros lotus andBroussonetia papyrifera.(4) The highest important value of the three kinds of community shrub layer was Grewia biloba. The important value of tree seedlings in shrub layer showed that, the natural regeneration ability ofQuercus variabilis community was highest; Robinia pseudoacacia community was higher thanPlatycladus orientalis community.(5) The species had high important value in three kinds of community herb layer were Arthraxonhispidus, Cleistogenes caespitosa and Setaira viridis which like light and drought environment. Therewere Carex lanceolata and Oxalis corniculata which like wet and shadow environment. There also weresome medicinal herbs such as Saposhnikovia divaricata, Leonurus heterophyllus and Adenophorapolyantha.(6) The species diversity results showed that the Margalef index (R), Shannon-Wiener index (H)and Pielou index (J) were herb layer> shrub layer> tree layer, Simpson index (D) was tree layer>shrub layer> herb layer in three typical forest communities.The species diversity of different stand was Robinia pseudoacacia> Platycladus orientalis>Quercus variabilis.The species diversity of Robinia pseudoacacia with different plantation age was30years>20years>40years>10years.On different slope aspects, for the Platycladus orientalis, the species diversity of tree layer on thesouthern slope was highest, shrub layer and herb layer on the western slope was highest. For theRobinia pseudoacacia, the species diversity of tree layer and shrub layer on the southern slope washighest, herb layer on the western slope was highest. For the Quercus variabilis, there was nosignificant differentiation on the different slope aspects.To different stand density of Platycladus orientalis, the species diversity of tree layer was mediumdensity>high density>low density, the shrub layer was high density>low density> medium density andthe herb layer was high density> medium density> low density.Therefore, from the stand age perspective, the positive human disturbance and regeneration shouldbe taken to the mature Robinia pseudoacacia forest. From the slope aspects perspective, the Robiniapseudoacacia forest and the Platycladus orientalis forest appropriate the northern slope. From the standintensity perspective, the suitable intensity of intermediate cutting should be taken to the tree layer ofthe Platycladus orientalis forest under high density to adjust the stands density and keep the speciesdiversity.