| National forest park is one of the important carriers to promote the construction of ecological documents.Stable forest ecosystem can provide good ecological services.With economic development and social progress,people’s spiritual and cultural needs show a diversified development trend.Returning to nature and experiencing nature has gradually become an important pursuit for a better life.Baili Rhododendron National Forest Park is rich in plant resources landscape is a forest ecosystem with special protection value,the naturally formed alpine evergreen rhododendron has high ecological benefits and ornamental value.Based on this,the Pudihua District and Jinpohua District in Baili Rhododendron National Forest Park were selected as the study area,and three road distance levels(mild disturbance,moderate disturbance and severe disturbance)were divided as continuous variables to calculate the alpha-diversity of plants in various community structure layers.Slope,slope position and altitude were selected as environmental factors,and Pearson correlation analysis was used to study the response of plant community species distribution pattern and vegetation-environment interaction of Rhododendrons in three continuous variables.Secondly,on the basis of field investigation,AHP was used to conduct comprehensive evaluation and classification of plant landscape in Baili Rhododendron National Forest Park,and a scientific and comprehensive evaluation of plant community landscape was obtained.The main research results are as follows:A total of 170 species belonging to 70 families and 128 genera were recorded.A total of109 species belonging to 49 families and 80 genera were recorded in Pudi landscape,including 39 species belonging to 30 families and 38 genera in mildly disturbed plots,73 species belonging to 37 families and 42 genera in moderately disturbed plots,and 69 species belonging to 33 families and 55 genera in severely disturbed plots.A total of 141 species in 92 genera and 53 families were recorded in Jinpo Scenic area.There were 68 species in 61 genera and 41 families in mildly disturbed plots,101 species in 79 genera and 47 families in moderately disturbed plots,and 77 species in 67 genera and 41 families in severely disturbed plots.Ericaceae accounted for 46.4%,Fagaceae 23.5%,Ferns 3.6%,Rosaceae 3.0% and Gramineae 2.3%,and other families accounted for 21.2%.The proportion of plant communities in Jinpo scenic spot was 40.5% of azaleas,7.6% of fagaceae,6.1% of gramineae,3.6% of ferns,3.3% of roseaceae and 38.9% of other families.(1)In Pudi scenic spot,there was no significant correlation between niche width of dominant species and disturbance intensity(P > 0.05).(2)Niche width of white oak in shrub layer was negatively correlated with disturbance intensity(p< 0.01),niche width of Rhododendron alluvium was positively correlated with human disturbance intensity(p < 0.05).(3)Niche width of herbs aceous ivy was positively correlated with disturbance intensity(p < 0.01),while niche width of oxtail was negatively correlated with disturbance intensity(p < 0.01).In Jinpo scenic spot:(1)Niche width of dominant tree species Quercus supraus was significantly positively correlated with disturbance intensity(P < 0.05),while niche width of white quercus was significantly negatively correlated with disturbance intensity(P < 0.05).(2)Niche width of white quercus in shrub layer was negatively correlated with disturbance intensity(p < 0.01).(3)There was a significant positive correlation between niche width and disturbance intensity(p < 0.05).The α diversity of plant community in Baili Rhododendron National Forest Park was affected by environmental factors,species composition and road distance.The α diversity of plant community in Pudi area and Jinpo area showed different characteristics on the whole.There was no significant correlation between α diversity of plant community structure layer and environmental factors in Pudi area.In Jinpo area of Pudi region,there were significant differences in the correlation between the environmental factors,species composition and road distance of the plant community in each structural layer.The species richness of trees,shrubs and herbs in Pudi flower area was significantly different,and the shrub layer was the highest,and the herb layer was the second.The α diversity of the tree layer was lower than that of the shrub layer and the herb layer.The α diversity of the tree layer was lower than that of the shrub layer,which was not conducive to the development of the ecological process of the whole community.The species diversity of structural layer in Jinpo area was significantly different from slope,species composition and road distance.The species richness indexes was the highest in shrub layer and the lowest in tree layer.The tree layer was the upper plant controlling the community change trend,and the overall species diversity was low,which was not beneficial to the long-term development of the community.There were differences in αdiversity between the two flower regions.The interaction between species and environment resulted from different species distribution patterns,which would affect the ecological process of the whole community.The β-diversity of plant community was different in the whole community and each structural layer of Rhododendrons National Forest Park.β diversity characteristics of whole community,tree layer,shrub layer and herb layer were calculated sequentially between two groups.The Cody indexes of Pudi flower area was the highest in the whole plant community,which was ranked as herb layer,shrub layer and tree layer.The overall Cody indexes showed a bimodal curve,and the overall trend of trees,shrubs and herbs was stable.At the level of Jaccard indexes and Sorenson indexes,the plant community showed the order of tree layer >community whole > shrub layer > herb layer.The Wilson Shmida indexes of plant community was stable in the whole,tree layer and shrub layer.The herb layer fluctuated greatly,and the overall change was in the order of herb layer > whole > shrub layer > tree layer.At the level of Cody indexes,Cody indexes values of the whole community,tree layer,shrub layer and herb layer showed a unimodal curve distribution,and the Cody indexes of the whole community was the highest,followed by shrub layer and tree and herb layer.The order of Jaccard index was tree > whole community > shrub > herb layer,and Sorenson index was tree > shrub > whole > herb layer.Wilson Shmida index of the plant community changed little in the whole,tree layer and shrub layer.The herb layer showed a multi-peak curve distribution,and the overall change was shrub layer > whole > tree layer > herb layer.Based on method of AHP,12 evaluation factors were selected from three levels of ornamental function,ecological function and service function to construct a comprehensive evaluation system of plant community landscape in Baili Rhododendron National Forest Park.An analysis of preference of evaluators for beauty degree of plant community landscape based on SBE method.Through Kendalls’ W concordant coefficient to test the evaluation results of AHP method and SBE method,it is concluded that W = 0.871 and the asymptotic significance is P = 0.000 < 0.05,indicating that the evaluation results of the two methods are consistent overall.Based on the comprehensive evaluation results of AHP and SBE,the spatial pattern of plant community landscape was optimized to enhance the ecological,aesthetic and socio-economic values of Baili Azalea National Forest Park. |
