Characteristics of soil seed banks of different plant communities and their relationships with soil nutrients in karst desertification area, North Gangxi, China

Abstract: As a repository of genetic information of above-ground vegetation, the soil seed bank plays an important role in the natural succession and renewal of vegetation and the construction of ecological restoration. In this paper, three typical plant communities in the rocky desertification area of Gongcheng Yao Autonomous County were selected for the study, Analysis of soil seed bank structure and diversity in different communities and their response to soil nutrient characteristics, In order to provide a theoretical basis for karst stone desertification management and vegetation restoration in Gongcheng County. The results were as follows：(1) A total of 3 648 seedlings belonging to 55 species in 51 genera and 33 families were detected, These seedlings include 20 species of 1, 2-year-old herbs, 21 species of perennial herbs, 5 species of vines, 3 species of shrubs and 6 species of trees; The average density of soil seed bank of different plant communities in karstic desertification areas of Gongcheng County was: Prunus salicina economic forest (22 493 seeds·m-2) > Cyclobalanopsis glauca secondary forest (1 033 seeds·m-2) > Phyllostachys sulphurea shrub (793 seeds·m-2). (2) As for the plant life type of the soil seed bank, The soil seed bank life type of Prunus salicina economic forest is mainly annual malignant weeds, The plant life type of the soil seed bank in the Cyclobalanopsis glauca secondary forest and Phyllostachys sulphurea shrub is dominated by perennial herbs, while woody plants account for a relatively small proportion; The species diversity and similarity of the soil seed banks of different vegetation types were generally low, while the species composition of the soil seed banks also had low similarity with the above-ground communities. (3) The soil elements in the study area had higher nitrogen content and lower phosphorus content, And phosphorus as a limiting factor for plant growth in Phyllostachys sulphurea shrub and Cyclobalanopsis glauca secondary forest; In a comprehensive view, the plant community in the stone desertification area of Gongcheng County has some native germplasm resources, but overall shows low species diversity, and it is urgent to introduce native tree species artificially to accelerate the positive vegetation succession on the basis of natural sequestration, and pay attention to nutrient management, especially the regulation of phosphorus elements.