Soil biota are critical drivers of plant growth, population dynamics, and community structure and thus have wide-ranging effects on ecosystem function. Interactions between plants and soil biota are complex, however, and can depend on the diversity and productivity of the plant community and environmental conditions. Plant-soil biota interactions may be especially important during stressful periods, such as drought, when plants can gain great benefits from beneficial biota but may be susceptible to antagonists. How soil biota respond to drought is also important and can influence plant growth following drought and leave legacies that affect future plant responses to soil biota and further drought. To explore how drought legacies and plant community context influence plant growth responses to soil biota and further drought, we collected soils from 12 grasslands varying in plant diversity and productivity where precipitation was experimentally reduced. We used these soils as inoculum in a growth chamber experiment testing how precipitation history (ambient or reduced) and soil biota (live or sterile soil inoculum) mediate plant growth and drought responses within an experimental plant community. We also tested whether these responses differed with the diversity and productivity of the community where the soil was collected. Plant growth responses to soil biota were positive when inoculated with soils from less diverse and productive plant communities and became negative as the diversity and productivity of the conditioning community increased. At low diversity, however, positive soil biota effects on plant growth were eliminated if precipitation had been reduced in the field, suggesting that diversity loss may heighten climate change sensitivity. Differences among species within the experimental community in their responses to soil biota and drought suggest that species benefitting from less drought sensitive soil biota may be able to compensate for some of this loss of productivity. Regardless of the plant species and soil origin, further drought eliminated any effects of soil biota on plant growth. Consequently, soil biota may be unable to buffer the effects of drought on primary productivity or other ecosystem functions as extreme events increase in frequency.
Whole-turf transplantation is a restoration method used to restore plant communities within disturbed arctic environments. Transplant expansion and restoration success is often determined based on aboveground characteristics, and to our knowledge, this is the first investigation of belowground expansion from transplanted turfs. In this growth chamber experiment, turfs harvested from undisturbed tundra near Rankin Inlet, Nunavut, Canada, were exposed to fertilized and unfertilized substrates to determine the effect of adjacent nutrient-enrichment on plant community composition within the turfs and substrates, as well as above and belowground biomass and expansion. Next-generation sequencing was used to determine the species identity of expanding roots. Our results show that fertilization of substrates surrounding tundra transplants did not alter the community composition of the turfs, but did increase biomass and expansion, as well as biological soil crust cover on the adjacent substrate. Belowground biomass far exceeded aboveground, revealing the importance of evaluating belowground roots and rhizomes that dominate the vegetative biomass within arctic ecosystems. Investigation of belowground development is likely to provide holistic interpretations of restoration success and should not be ignored in future transplantation studies.
Disturbed low-Arctic environments provide many challenges for ecological restoration, from harsh climates and remote locations to limited knowledge on plant establishment and successional pathways within tundra ecosystems. Due to limited commercially available materials for restoration of native low-Arctic plant communities, transplantation may provide an effective technique for revegetation in these difficult-to-restore environments. In this study, whole-turfs and shredded turfs were harvested from undisturbed upland-heath tundra near Rankin Inlet, Canada, and transplanted onto nearby disturbed gravel quarries to investigate species survivability and development of upland-heath vegetative communities. Two years following transplantation, turfs were found to maintain 85% of the initial vegetative cover and 91% of the initial species richness, with expansion up to 8 cm into the surrounding substrate, and production of seeds and spores. Although shredded turfs were unable to significantly establish vascular species, evidence suggests a shredded turf may establish non-vascular plant cover over a larger area than intact turfs, if given greater protection from environmental stressors. Our results demonstrate that whole-turfs are resistant to harvesting and transplantation stresses, flooding, drought, and poor soil conditions, and are an effective means of species transfer promoting development of vegetative cover on disturbed substrates. High species survivability indicates that turfs have the potential to provide disturbed areas with a wide array of native species, critical for the development of sustainable and self-organizing assemblages of native vegetation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.