Effects Of Plant-soil Feedback On Species Diversity And Species Interactinon

The study on the succession,stability and diversity of grassland community from the perspective of plant-soil feedback(PSF)has become a hotspot.However,little research has been done on the effects of plant-soil feedback on species interaction and diversity,and the mechanism of action.It is necessary to explore the effects of plant-soil feedback on the patchy distribution of grassland under the regulation of interspecific relationship.The impacts of species diversity on grassland stability and productivity are helpful to understand the intraspecific and interspecific relationships and the processes of species diversity on grassland stability and productivity,thus providing technical support and scientific basis for the establishment of efficient artificial mixed grassland and the relief of natural grassland pressure.The experiment took artificial mixed grassland as the research object.Different soil conditions were obtained by setting different species diversity and patch size combinations.Pot experiments were conducted under different soil conditions to observe the feedback between plants and soil,and to explore the effects of plant-soil feedback on species diversity and interspecific relationship.The main results of this experiment are as follows:(1)The yield of forage growing in heterologous soil was significantly higher than that in homologous soil;the yield of mixed forage was significantly higher than that of single forage,and the yield of forage increased with the increase of species diversity.Soil microbial community has a certain effect on forage yield.(2)Soil feedback of coexisting species is affected by interspecific competition in soybean-grass mixed grassland.Compared with single sowing,the PSFs of tall fescue in mixed grassland were inhibited,while the PSFs of white clover in legume were changed from positive feedback to negative feedback,indicating that the higher competitiveness of tall fescue was due to the nutrient supply of white clover.(3)Spatial heterogeneity of PSFs in mixed grassland allows forage to grow selectively in heterogeneous soil patches,thus affecting forage yield and competitiveness by reducing growth differences among competing species,thereby promoting the coexistence of species in mixed grassland.(4)The PSFs response of forage depends on forage species and planting methods(single or mixed sowing).Compared with intraspecific competition,interspecific competition strengthens negative plant-soil feedback of species,and species diversity and patchy distribution patterns affect the relative competitiveness of mixed species through plant-soil feedback.This effect varies with the change of forage species,and it is possible to maintain species coexistence by limiting dominant species.