Understanding how climate change and variability will impact grassland ecosystems is crucial for successful grasslands management in the future. In 2020, the North Central Climate Adaptation Science Center began a project to establish a baseline of information to best serve grassland managers (that is, those individuals who develop grassland management plans, implement those plans on the ground, or both) at Federal, State, and Tribal agencies; nongovernmental organizations; and partnerships to help meet regional grassland management goals. This chapter presents the main findings from the review and synthesis of 183 grassland management-related documents relevant to the North Central region. Specifically, this chapter describes the methods by which grassland management-related documents were identified, reviewed, and synthesized; defines five North Central Grassland Ecoregions; provides a synthesis of regional grassland management goals and challenges; identifies information needs relevant to grassland management in a changing climate; and summarizes grassland management issues by ecoregion.
Process-based restoration (PBR) of streams—a suite of techniques developed in mountainous regions—is now being applied to prairie streams with different geomorphological, hydrological, and ecological conditions. In October 2024, we held a meeting of stream restoration practitioners to share outcomes from initial prairie PBR projects—primarily large-wood additions and beaver mimicry and restoration. Practitioners agreed that geomorphological processes sustaining prairie streams are not well understood, and this leads to disagreement about the efficacy of specific restoration techniques. While beaver dams were present on pre-colonization prairie streams, the ability of beaver mimicry projects to recruit beaver and sustain natural processes is poorly characterized. Biological responses to prairie PBR appear positive, but the response of many taxa and the social acceptability of projects has not been studied. We highlight a substantial area of data deficiency and identify the need for more research on prairie PBR projects.
Climate change poses a unique set of escalating challenges for Canyons of the Ancients National Monument (CANM). A 2021 manager’s report specified that the rapidly changing climate makes fulfilling CANM’s purpose of protecting natural and cultural features exceedingly difficult due to the uncertainty global warming introduces across CANM’s diverse biomes. “While the landscape itself, defined by rugged terrain and harsh conditions, resulted in vegetation communities that are well adapted to extremes, the uncertainty of future climate conditions makes predicting the stability, or instability of those communities nearly impossible,” (O’Neil et al 2021: 9). Recent years, characterized by rising temperatures, drought, and unpredictable precipitation, make “planning for revegetation, hazardous fuels reductions, and riparian restoration projects more difficult and diminishes the opportunities for success” (O’Neil et al 2021: 9.) Moreover, these climate impacts also imperil the tens of thousands of cultural features and ancestral sites that the monument was created to protect. To begin addressing these challenges, this assessment considers how climate change could impact important habitats of the Monument and how those impacts pose specific threats to ancestral sites. Findings from this work could help inform the future development of a Science Plan for CANM. Overseen by the Bureau of Land Management, CANM maintains ongoing partnerships with 26 tribal communities who trace enduring connections to the landscape and ancestral features (Figure 1). Partnering with descendant communities is crucial for the development of plans to adapt CANM to risks posed by a rapidly changing climate.
Climate change is contributing to unprecedented rates of ecological transformation worldwide. Shifts in species distributions and altered structural complexity of habitat has implications for ecosystem function and human relationships. The 1964 Wilderness Act was passed to preserve undeveloped large landscapes in their “natural” condition and for the continued recreational, cultural, and spiritual benefit of the people. Nevertheless, wilderness is still vulnerable to the direct and indirect impacts of climate change. Using active management to respond to climate change challenges in wilderness is complicated by the very protections afforded to wilderness that limit human impacts. This conundrum manifests as a wicked problem for land stewards who are grappling with how to prepare for or respond to climate change-driven ecological transformation. In the Black Ridge Canyons Wilderness (BRCW) of southwest Colorado, USA, climate change is impacting habitat conditions for native amphibians and exacerbating adverse interactions between native and invasive amphibian species. This report summarizes research and activities relevant to the RAD Decisions in Rad Landscapes: Black Ridge Canyons Wilderness case study. The overarching goal of this case study was to provide Bureau of Land Management (BLM) staff and their partners with knowledge and tools to support intentional and transparent decisionmaking for ephemeral riparian communities in the BRCW through climate change-driven ecological transformation. Scientists from the Aldo Leopold Wilderness Research Institute (ALWRI) conducted research to illuminate the potential ecological consequences of climate change for ephemeral riparian communities as well as managers’ perceived ability to respond to ecological change. Additionally, scientists at AWLRI facilitated a 2-day workshop which engaged BLM staff and their partners in an adaptive management process to clarify values and desired conditions, generate decision alternatives under the RAD framework, and evaluate the potential social, legal, and ecological implications of various decision alternatives for native amphibian communities within the BRCW.
Urban forests and other green infrastructures have been viewed as part of the “Nature‐basedSolutions” (NbS) to mitigate emerging urban environmental change. This study focuses on the role ofevapotranspiration (ET) in regulating water balances of small watersheds in the eastern United States. Wecompared streamflow and ET patterns at daily, monthly and annual scales and linked these hydrologicalvariables to the physical properties of 11 paired watersheds dominated by forests (FW) or urban (UW) landcovers. The annual precipitation ranged from 1028 mm to 1683 mm and potential ET (PET) from 815 mm to1450 mm. The mean annual flow/precipitation (Q/P) ratios were 0.26 ± 0.13 and 0.41 ± 0.1 for FW and UW,respectively. Overall, UW had lower annual ET (772 mm in UW vs. 947 mm in FW), but higher mean annualand (∼58% higher), monthly water yield (17%–186% higher), and peakflow rates (up to 100 times higher) thanFW. The streamflow differences between FW and UW were most pronounced during the growing season andearly winter (June‐November). The mean Q/P ratios for 30 large hurricane events (2016–2021) were 0.12 ± 0.11and 0.38 ± 0.23 for FW and UW, respectively. The flow rates in the dormant season (around December‐May) inUW were similar or lower than FW. We developed conceptual models to explain the seasonal and storm eventstreamflow differences using background climate (PET), ET, and land surface characteristics. Urban NbSdesigns should factor in strategies that maximize ET while minimizing impervious surfaces enhancingwatershed “sponge” and “pump” functions.
Climate change and land use change are crucial determinants of crop water consumption, particularly in drylands where water scarcity limits crop production. In Central Asia, the effects of land use and climate changes on crop water consumption remain unknown. We estimated the dynamics of crop water consumption by mapping annual actual evapotranspiration from Landsat imagery from 1987 to 2019 for all irrigated croplands in the Amu Darya Basin, the largest transboundary river in Central Asia. Total crop water consumption increased by 10%, while average consumption per unit area increased by 18%. Climate change was the main driver of the rising crop water consumption; land use changes towards less water-intensive cropping practices offset only 3% of this increase. Our findings underscore that crop production will become increasingly challenging amidst accelerating climatic changes and that changing cropping practices alone will be insufficient to curb the growing water scarcity without a global commitment to reducing emissions.
Ecosystem exchanges of carbon, water, and energy are central to Earth system functioning, yet their sensitivities to environmental variability remain poorly constrained across biomes and climates. Here, we analyzed ≥ 5 years of eddy covariance data from 87 AmeriFlux sites (964 site-years) spanning six vegetation types and a broad range of climatic conditions to examine the controls and multi-year trends of gross primary productivity (GPP), evapotranspiration (ET), water-use efficiency (WUE), and the Bowen ratio. We trained boosted regression tree ensembles with environmental (air temperature, vapor pressure deficit, soil water content, atmospheric CO2, radiation, wind speed) and temporal (month, year) variables and used interpretable machine learning—SHapley Additive exPlanations (SHAP) and Accumulated Local Effects (ALE)—to quantify driver importance and nonlinear responses. Across biomes and along climatic gradients, environmental controls reorganized predictably: radiation dominated under warm and humid conditions, whereas soil moisture exerted a stronger influence in drier or warmer systems. GPP and ET were shaped by similar dominant drivers, with radiation and temperature generally strongest but soil moisture exerting comparable influence in some biomes. WUE was consistently constrained by vapor pressure deficit, indicating stomatal regulation under rising atmospheric dryness. In contrast, controls on the Bowen ratio diverged more across biomes, indicating heterogeneity in how ecosystems partition energy between latent and sensible heat. Multi-year trend analysis revealed negative associations of GPP and ET with rising atmospheric demand, and positive associations of the Bowen ratio with drying, indicating reduced evaporative cooling and stronger land–atmosphere coupling. Together, these findings show that while carbon and water fluxes remain tightly coupled across timescales, their balances reorganize predictably along bioclimatic gradients. This framework underscores the value of long-term flux networks and interpretable machine learning for benchmarking Earth system models and constraining projections of terrestrial carbon–water–energy dynamics under climate change.
Background Wildfires are burning more area across the western US than they have in the recent past, driving an increased need for post-fire reforestation. At the same time, trees are struggling to keep up with climate change and post-fire tree planting may present an opportunity to plant seedlings from seed sources adapted to changing conditions. To better understand how reforestation outcomes for an ecologically and economically important conifer species in the northwestern US vary with seed source and site conditions, we conducted a post-fire western larch (Larix occidentalis) planting experiment in western Montana. We ask (1) what biophysical factors influence post-fire western larch planted seedling mortality and growth? and (2) does planting seedlings from a lower-elevation seed source decrease mortality at the driest and warmest sites and/or increase mortality at the coldest sites? Results We planted western larch seedlings from a low-elevation and a high-elevation seed source across an elevation gradient and monitored seedling mortality and growth for 3 years. Overall seedling mortality 3 years post-planting was similar between seed sources with higher and more variable mortality in the low-elevation plots (ranging from 15 to 94% depending on seed source and plot combination; mean (sd) 60(28)%) and lower mortality in the mid-elevation and high-elevation plots (2–19%; mean (sd) 9(5.6)%). Planting seedlings from a lower-elevation seed source did not increase short-term mortality at the highest-elevation plots. Seedling mortality and growth were strongly related to site conditions, with higher mortality and lower growth associated with more southerly aspects, higher maximum temperatures, and lower soil moisture. Seedlings from the high-elevation seed source showed a stronger negative response to high maximum temperatures than seedlings from the low-elevation seed source for both mortality and growth. Conclusions Biophysical conditions at the planting site were the stronger drivers of seedling mortality, with seed source acting as a secondary control. Interactive effects between microclimate and seed source suggest that seedlings from the low-elevation seed source may perform better under warming conditions. For western larch reforestation, site selection may have more impact on short-term survival than planting different seed sources, although we find some evidence that seed source may mediate responses to warming. Longer-term outcomes will require additional monitoring.
Hybrid invited paper session recorded at the Ecological Society of America's Annual Meeting in Portland, Oregon. August 6-11, 2023. OOS 67.