Responses of Different Plant Taxonomic Groups to Complex Environmental Factors in Peri-Urban Wetlands

Abstract

Wetland plants are essential for ecosystem functions. However, wetland plants in peri-urban areas have been affected by increased human interference. Hence, analyzing the drivers of plant diversity could be extremely useful for biodiversity conservation. The main objective was to investigate the response of plant diversity in wetlands (e.g., plant richness, plant abundance, and taxonomic distinctness) to the environment in peri-urban areas. The results show that the wetland area is the most important factor influencing plant diversity in peri-urban areas. Plant richness and abundance decreased significantly with a decreasing wetland area. The cultivated land decreased the abundance of native plants and indirectly promoted native plant growth and spread by increasing the total organic carbon content of the water. Forest encroachment on wetlands significantly reduced native plant abundance. The effects of soil pH, water body pH, soil organic matter, and slope on introduced species showed opposite trends to those on native plants. Introduced plants were significantly more adapted to the land use around the wetland than native plants. The green land and forest areas promoted the spread of introduced plants. Introduced plants were significantly less adapted to the physicochemical properties of the soil and water than native species. Humans, through agricultural cultivation, have caused introduced plants in cultivated lands to escape to wetlands, resulting in an increase in introduced species. The riparian zone length showed opposite effects for aquatic and terrestrial plants. Pollution from urbanization and agriculture both positively and negatively affects aquatic plants. The response of aquatic plants to nutrients in the water was better than their response to soil nutrients and the response of terrestrial plants to soil nutrients. Terrestrial plants can better withstand pollution from urbanization and agricultural activities, as well as the erosion of wetlands from forested and cultivated lands.