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Ecosystem services, essential for supporting life, are increasingly being altered by anthropogenic activities. This study focuses on the Cross Timbers ecoregion of the southern Great Plains, USA, where oak woodland and grassland co-exist. However, grasslands are rapidly transitioning to woodlands through a process known as woody plant encroachment, or are being considered for switchgrass biofuel production. Our objectives were to quantify the supporting (plant biodiversity, aboveground net primary productivity), provisioning (water quantity, forage production), regulating (soil organic carbon, flood regulation), and cultural services (hunting-based recreation, aesthetics) of four land use types—tallgrass prairie, oak woodland, eastern redcedar woodland, and switchgrass biofuel production—using the Millennium Ecosystem Assessment Framework. We integrated these services into an ecosystem sustainability index. Results showed that tallgrass prairie provided balanced services and ranked highest in this index. Eastern redcedar and switchgrass exhibited an imbalance in services, while oak woodland’s ranking varied with normalization methods. Our results highlight the need for grassland conservation by curtailment of eastern redcedar expansion. While oak woodland ranks high in cultural services, its restoration is recommended to enhance multiple ecosystem services. This study provides a roadmap for quantitatively evaluating ecosystem services to inform management decisions for ecosystem transitions and promote regional sustainability. Future research should broaden stakeholder engagement and explore integrated land use strategies within large watersheds encompassing multiple land uses to enhance regional environmental sustainability.
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Consumer roles of small mammals within fragmented native tallgrass prairie
Abstract Grassland ecosystems globally are being negatively impacted by changes in climate, disturbance regimes, nutrient flux, and consumer guilds. Changes in the trophic ecology of consumers can substantially influence local resources, contributing to shifting diversity, community turnover, and other processes of ecosystem change. Small mammals are diverse and abundant within grasslands and yet the impact of changing ecosystems on small mammals and the role of these mammals as consumers are still both under‐studied. We assessed small mammal resource use within grassland and woodland vegetation types that have resulted from landscape‐scale experimental disturbance through fire treatments within the tallgrass prairie ecoregion of the North American Great Plains. We predicted that resource use would vary significantly among grassland vs. woodland communities, in turn reducing the role of small mammals in contributing to future maintenance of native prairies. We sampled five dominant species of rodents across three years and multiple habitats. Using stable isotope analysis, we investigated isotopic niche area and overlap to infer variation in diet, both within and among species. Resource use shifted in bivariate isotopic space seasonally but not across years when combining all species and habitats. Inferred spring diet (based on fur samples) was highly diverse and overlapping. Summer isotopic values (based on liver tissue) in woody habitat treatments were narrower and overlapped less than within grassland habitats. Consumers generally shifted from C4herbivory to C3herbivory, or greater omnivory, when analyzing grassland, shrubland, and woodland habitats respectively. Within the tallgrass prairie ecosystem, small mammal populations in herbaceous‐dominated habitats use a broader variety of resources than small mammals in proximate woody‐dominated habitats. As native grasslands experience woody encroachment, small mammal assemblages experience turnover of dominant species and associated changes in diet. Ecosystem changes such as cessation of frequent fire resulting in more woody habitats may include reduced roles by native small mammals as consumers/dispersers/propagators of native grassland plants.
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- Award ID(s):
- 2025849
- PAR ID:
- 10452776
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 12
- Issue:
- 3
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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