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Abstract ContextThe > 25,000 km2Flint Hills ecoregion in eastern Kansas and northeastern Oklahoma, USA, is an economically and ecologically important area encompassing the largest remaining tallgrass prairie ecosystem in North America. Prescribed fires are used routinely to control invasive woody species and improve forage production for the beef-cattle industry. However, burning releases harmful pollutants that, at times, contribute to air quality problems for communities across a multi-state area. ObjectivesEstablish a modeling framework for synthesizing long-term ecological data in support of Flint Hills tallgrass prairie management goals for identifying how much, where, and when rangeland burning can be conducted to maximize ecological and economic benefits while minimizing regional air quality impacts. MethodsWe used EPA’s VELMA ecohydrology model to synthesize long-term experimental data at the 35 km2Konza Prairie Biological Station (KPBS) describing the effects of climate, fire, grazing, topography, and soil moisture and nutrient dynamics on tallgrass prairie productivity and fuel loads; and to spatially extrapolate that synthesis to estimate grassland productivity and fuel loads across the nearly 1000 times larger Flint Hills ecoregion to support prescribed burning smoke trajectory modeling using the State of Kansas implementation of the U.S. Forest Service BlueSky framework. ResultsVELMA provided a performance-tested synthesis of KPBS data from field observations and experiments, thereby establishing a tool for regionally simulating the combined effects of climate, fire, grazing, topography, soil moisture, and nutrients on tallgrass prairie productivity and fuel loads. VELMA’s extrapolation of that synthesis allowed difficult-to-quantify fuel loads to be mapped across the Flint Hills to support environmental decision making, such as forecasting when, where, and how prescribed burning will have the least impact on downwind population centers. ConclusionsOur regional spatial and temporal extrapolation of VELMA’s KPBS data synthesis posits that the effects of integrated ecohydrological processes operate similarly across tallgrass prairie spatial scales. Based on multi-scale performance tests of the VELMA-BlueSky toolset, our multi-institution team is confident that it can assist stakeholders and decision makers in realistically exploring tallgrass prairie management options for balancing air quality, tallgrass prairie sustainability, and associated economic benefits for the Flint Hills ecoregion and downwind communities.
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Quantitative assessment of ecosystem services in diverse land uses within the forest-grassland transition zone of southern Great Plains, USA
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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- Award ID(s):
- 2216648
- PAR ID:
- 10590257
- Publisher / Repository:
- science direct
- Date Published:
- Journal Name:
- Ecosystem Services
- Volume:
- 71
- Issue:
- C
- ISSN:
- 2212-0416
- Page Range / eLocation ID:
- 101697
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.ecoser.2025.101697
