| The Qinling Mountains is located in the middle of China,which is the North-South boundary and contains complex and diverse habitats,so the plant species are also very rich.Studying the relationship between plant diversity and environmental factors is of great significance for the protection and utilization of biodiversity and the long-term monitoring of seed plant diversity in this region.This study takes the seed plants of the North Branch of the western Qinling Mountains as the research object.By establishing a plant database containing species names,distribution areas,invasion and protection levels,on this basis,the open environmental factor data are used to find the factors related to species richness,and analyze the main threatened species and causes in diversity protection,which is conducive to further protecting local plant diversity.The main conclusions are as follows:1 There are 2,136 species of seed plants belonging to 725 genera,141 families in the North Branch of the western Qinling Mountains(including varieties and forms,APG â…£classification system).The composition of geographical elements in the study area is diverse.The temperate elements account for the highest proportion in both family and genus distribution types,followed by tropical elements,showing a transitional nature.2.The altitude of the northern branch of the western Qinling mountains ranges from749 m to 2,369 m,and the trend of species richness shows a single peak curve,with the peak at 1,300 m to 1,500 m above sea level.The region with the highest species richness is in the Jialing River Basin on the southern slope of the Qinling Mountains,especially in the north of Hui County,while the species richness on both sides of the Weihe River and the Guanshan grassland in Longxian county is low.The relationship between plant richness and precipitation is the largest.The species richness in Xinjia mountain,Guanshan grassland and Jiulong Mountain in the east of the study area is positively correlated with the coefficient of precipitation variability and significantly negatively correlated with the annual precipitation and the driest quarter precipitation.The plant richness in the middle of the study area is negatively correlated with the driest quarter precipitation.3.There are 25 families,38 genera and 43 species of protected species in the study area,and the number of herbaceous species accounts for the largest proportion of the number of protected species.There are 75 species of alien invasive plants belonging to 55 genera and26 families.Human activities such as mining,road construction and forest tending in the Qinling Mountains have damaged the habitat of wild plants,and obviously threatened the survival of Acer Miaotai,Lianxiang,Taxus chinensis and Taxus chinensis.The following countermeasures must be taken for effective protection: reducing human interference,improving laws and regulations,and strengthening publicity and education activities;Implement on-site protection and ex situ protection,protect and manage rare and endangered species at different levels,and promote species breeding;Attach importance to biological threats,strengthen the prevention and control of plant diseases and pests,and conduct comprehensive management and monitoring to strictly prevent the invasion of alien species. |
