| Vegetation restoration,as the starting point and fundamental measure of rock desertification control,has attracted the attention of many researchers.Gongcheng Yao Autonomous County is located in the northeast of Guangxi Zhuang autonomous Region.Rocky desertification was once one of the major environmental problems restricting the economic development of the county.In recent years,the continuous change of land use nature has led to the destruction of original vegetation resources,vegetation degradation and biodiversity reduction.This study based on Gong Cheng rocky desertification area land vegetation,soil chemical properties,soil seed bank survey,analysis and contact the ground,underground vegetation species composition,discusses different typical rocky desertification vegetation in the habitat,and effect on soil seed Banks in the process of vegetation restoration,a preliminary analysis,on the basis of which the vegetation restoration of corresponding countermeasures.The main results are as follows:(1)The survey of the three typical vegetation types found that there were 96 species of aboveground vegetation,belonging to 38 families and 91 genera,and a total of 55 species germinated in the soil seed bank,belonging to 33 families and 51 genera.The species diversity index in the rocky desertification area of Gongcheng County is low,and the restoration of the ecological environment is urgent.(2)The stability of the plum forest community is poor,and it is seriously disturbed by human beings.The life forms of species are mainly annual herbs,and most of them are malignant weeds,and the species diversity index is low.The long-term use of pesticides and fertilizers results in extremely high levels of organic carbon,total nitrogen,total phosphorus,total potassium,alkali-hydrolyzed nitrogen,available phosphorus and available potassium in the soil.The number of species germinated in the soil seed bank is relatively large,and annual or perennial herbs account for the vast majority.The similarity coefficient of aboveground and belowground species composition is 0.16,and the species richness of soil seed bank is much greater than that of aboveground vegetation.(3)The community stability of P.japonicum forest was relatively good,but the structure was unreasonable.The life forms of species were mainly composed of perennial herbaceous and perennial woody lianas.As the absolute dominant species,Goldenrod hindered the development of other species,and the entangling of perennial woody vines also affected the growth of other species.The biodiversity index was moderate,the soil nutrients showed obvious phosphorus limitation,and the contents of organic carbon,total nitrogen and alkali-hydrolyzable nitrogen were very high.Seed bank reserves are scarce,mainly perennial herbaceous.The similarity coefficient of aboveground and underground species composition was 0.2,and some species that had not been found in aboveground investigation spied.(4)The primary forest has a reasonable community structure,strong anti-interference ability,and is less affected by human activities.The above-ground vegetation has obvious stratification of trees,shrubs and grass,and perennial herbs are dominant in the soil seed bank.Soil seed density is low,the number is small,there is a certain degree of vertical distribution law.Phosphorus is extremely scarce in the soil,at very low levels in the national soil survey.The similarity coefficient of aboveground and underground species composition was 0.14,and the species richness of aboveground vegetation was much higher than that of soil seed bank.(5)According to the characteristics of the three typical vegetation types,the original malignant weeds should be removed and the species with both economic and ecological benefits should be planted in plum forest.Three-dimensional agriculture and compound ecological agriculture should be considered.In order to increase its biodiversity,some species should be selected and introduced artificially.Native forest can be protected by legislation to prevent reverse succession of potential rocky desertification.According to the chemical properties of soil,phosphorus fertilizer can be applied in p.japonicum forest and primary forest to control the use of pesticides and chemical fertilizers in Plum forest. |
