| The Jingwei Wetland Nature Reserve in Xi’an has a large amount of wetland resources,which play a crucial role in maintaining biodiversity,climate regulation,water quality purification,and other aspects of the city.However,in the unstoppable urbanization process of Xi’an,it gradually becomes an urban wetland,which is a challenge for its own ecosystem and faces enormous human activity and climate pressure.Wetland plants are indispensable elements in the structure and function of wetland ecosystems,playing an important role in the ecosystem,while vegetation degradation is the most common problem in wetlands.Studying the plant resources of the Jingwei Wetland to provide data support for the management of protected areas is of great practical significance.This study used 3S technology to design wetland sample lines and conducted a comprehensive survey of the vegetation of the Jingwei Wetland in Xi’an.The plant species composition,family and genus species diversity,life form,number of rare and endangered plants,key protected plants,and number of invasive plants were analyzed and counted;Based on relevant research by Academician Zhengyi Wu and others,divide the geographical components of plants in the Jingwei Wetland;Using the MaxEnt model to predict changes in the suitable habitat for invasive plants,the results are as follows:(1)The Jingwei Wetland has a high diversity of vascular plants.In this field survey,420 species of vascular plants belonging to 96 families and 301 genera were counted in the Jing Wei wetland,with angiosperms accounting for absolute advantage;According to the classification of plant life forms,herbs accounted for the largest proportion;From the perspective of intra family genera,single genus and oligogenus families are the majority,accounting for 86.46 % of the total number of families in the Jingwei Wetland;From the perspective of species within the family,there are the most oligospecific families,totaling 49families;At the level of subspecies,the single genus is the most abundant,accounting for75.08 % of the total genera in the protected area.(2)The Jingwei Wetland is rich in plant resources.There are a total of 13 national and provincial rare and endangered plants in the protected area,of which 10 are national rare and endangered plants,accounting for 2.38 % of the total number of vascular plants in the Jingwei Wetland;There are a total of 11 nationally and provincial-level key protected plants,including2 national level I key protected plants and 7 national level II key protected plants.(3)There are diverse invasive plants in the Jingwei Wetland.The origin comes from Brazil,North America,Mexico,Central Asia,South America,Europe,India,West Asia,and North Africa;Belonging to the family Plantaginaceae,Fabaceae,Malvaceae,Poacea,Compositae,Onagraceae,Solanaceae,Cyperaceae,Phytolaccaceae,Amaryllidaceae,Amaranthaceae,etc.Among them,there are a total of 18 species of highly harmful Grade 1malignant invasive plants and Grade 2 severe invasive plants.(4)The geographical composition of plants in the Jingwei Wetland shows a close correlation between temperate and tropical components.At the plant family level,the proportion of temperate and tropical components in non world wide distributed genera is the same;At the plant genus level,the proportion of temperate components in non world wide distributed genera is the highest,accounting for 68.72 % of non world wide distributed genera in total.(5)The adaptability of the Jingwei Wetland and even the entire Guanzhong area in Shaanxi Province to Symphyotrichum subulatum is increasing.From the distribution map of adaptability levels,amplification reduction area map,and centroid transfer analysis map of the first level malignant invasive plant Symphyotrichum subulatum under future climate conditions,it can be seen that regardless of whether under the SSP1-2.6,SSP2-4.5,SSP3-7.0,or SSP5-8.5 pathways,the total adaptability area of Symphyotrichum subulatum in the future period shows a trend of expansion along the north,and the distribution centroid shows a clear trend of moving along the northwest direction.The Jingwei Wetland has abundant plant resources and complex components,but invasive plants are widely distributed and of diverse types,which may gradually lead to the singularity and degradation of the Jingwei Wetland ecosystem.This study can provide data support for the long-term restoration plan,dynamic monitoring of wetland plants,comprehensive plant protection measures,vegetation restoration,and invasive species prevention and control of the Jingwei Wetland.It can also provide a foundation for the importance of plant species in the Jingwei Wetland and the response of plants to environmental factors. |
