The Impact of Elevation on the Ecological Niche and Interspecific Association of Wild Fruit Forests in Tacheng Area
As an important component of the wild fruit forest in Tacheng,Xinjiang,the wild fruit forest plays a crucial role in maintaining local species diversity.To explore the impact of habitat factors on the ecological niche and interspecific relationships of wild fruit forests in this region,80 plots of 30×30 meters were established in Emin County,Yumin County,and Toli Count,recording six habitat factor parameters:altitude,slope,aspect,soil moisture content,pH,and herbaceous coverage.The impact of habitat factors on species distribution was analyzed through Mantel test,and the most influential habitat factors were divided into 4 levels.Levins niche width index,Spearman rank correlation number(rik),Shannon-wiener index,and Simpson index were used for analysis.The results showed that,1)among the six habitat factors,altitude had the greatest impact on the distribution of tree species(Mantel index was 0.2615),and showed extremely significant(P=0.0001);next were soil moisture content and herbaceous coverage(Mantel in-dices of 0.1092 and 0.0987,respectively).2)The main tree species in the wild fruit forest of Tacheng area were Malus sieversii,Crataegus pinnatifida,and Spiraea salicifolia,which were mainly distributed at an altitude of 1100-1300 meters.3)The frequency and niche width of Malus sieversii were the highest at all levels,while other tree species showed significant differences at different levels.With the increase of altitude,the frequency and niche width of tree species showed a trend of first increasing and then decreasing.4)At four altitudes(the first level is 700-900 meters,the second level is 900-1100 meters,the third level is 1100-1300 meters,and the fourth level is 1300-1500 meters),Oik>0 accounted for 83.33%,65.38%,60.44%,and 76.19%of the ecological niche overlap a-mong tree species,respectively;the ecological niche overlap index showed a trend of first decreasing and then increasing with the in-crease of altitude.5)At four altitudes,rik≥0 accounted for 66.67%,58.97%,35.16%,and 38.10%of the positive correlations a-mong tree species at corresponding altitudes;tree species exhibited a predominantly positive correlation in the first and second levels,while negative correlation was predominant in the third and fourth levels.At the same time,positive correlation,significant positive correlation,and significant negative correlation showed a trend of first decreasing and then increasing with increasing altitude,while no significant correlation showed a trend of first increasing and then decreasing.The results indicated that,altitude was the main influen-cing factor on the distribution of wild fruit forest species in the Tacheng area,as the altitude increased,the frequency of tree species and niche width showed a trend of first increasing and then decreasing,while the niche overlap index and inter species correlation showed a trend of first decreasing and then increasing,at an altitude of 1100 to 1300 meters,tree species had better distribution and interspecific relationships.
Wild fruit forestelevationcommunity patternsample site surveyhabitat factorspecies association
万方数据
维普
