Biological invasions by non-native plants are a major cause of native ecosystem loss, and restorations following eradication of invasive species are often unsuccessful. There is growing recognition that interactions with belowground microorganisms play fundamental roles in restoration success, and non-native plants species have been shown to alter native soil communities, including arbuscular mycorrhizal (AM) fungi on which native species depend. We have conducted a series of cross-site studies on Oklahoma and Kansas (USA) to investigate potential effects of invasive non-native, warm-season grasses (Bothriochloa spp.) on biotic or abiotic soil properties. Further, we are evaluating the potential benefits of inoculation with native soil or native AM fungal communities to control non-native plant invasions and enhance restoration of ecosystem function. In addition to improving restoration success, re-establishing AM fungi can improve soil aggregate stability, thereby potentially contributing to soil carbon storage. Therefore, restoration of native soil microbial communities, including AM fungi, may be a useful tool to restore native plants and ecosystem function of grasslands.
Results/Conclusions
Our research indicates invasion by these non-native grasses disrupt native soil microbial communities, including AM fungi. However, our previous and on-going research has shown that the degradation of this symbiotic fungal community can be ameliorated by the introduction of prairie soil, with markedly improved success of native plant restorations and reductions in further invasion by the invasive grasses. However, inoculating with native prairie soil is not practical for large scale restorations. Therefore, we are assessing the potential to restore native soil communities by inoculation with AM fungi cultured from native prairies. Our approach is to inoculate nurse plants and allow the native AM fungi to benefit adjacent non-inoculated plants. Our research shows promise, as transplanting nurse plants inoculated with native AM fungi significantly increased the establishment, survival, and growth of native prairie plants. Our research indicates inoculation with native microbes may play an important role in successful restoration of damaged grasslands.