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America’s remaining grassland in the Prairie Pothole Region (PPR) is at risk of being lost to crop production. When crop prices are high, like the historically high corn prices that the U.S. experienced between 2008 and 2014, the risk of grassland conversion is even higher. Changing climate will add uncertainties to any efforts toward conservation of grassland in the PPR. Grassland conversion to cropland in the region would imperil nesting waterfowl among other species and further impair water quality in the Mississippi watershed. In this project, we sought to contribute to the understanding of land conversion in the PPR with the aim to better target the use of public and private funds allocated toward incentivizing...
A warming climate, fire exclusion, and land cover changes are altering the conditions that produced historical fire regimes and facilitating increased recent wildfire activity in the northwestern United States. Understanding the impacts of changing fire regimes on forest recruitment and succession, species distributions, carbon cycling, and ecosystem services is critical, but challenging across broad spatial scales. One important and understudied aspect of fire regimes is the unburned area within fire perimeters; these areas can function as fire refugia across the landscape during and after wildfire by providing habitat and seed sources. With increasing fire activity, there is speculation that fire intensity and...
Wildfire refugia are forest patches that are minimally-impacted by fire and provide critical habitats for fire-sensitive species and seed sources for post-fire forest regeneration. Wildfire refugia are relatively understudied, particularly concerning the impacts of subsequent fires on existing refugia. We opportunistically re-visited 122 sites classified in 1994 for a prior fire refugia study, which were burned by two wildfires in 2012 in the Cascade mountains of central Washington, USA. We evaluated the fire effects for historically persistent fire refugia and compared them to the surrounding non-refugial forest matrix. Of 122 total refugial (43 plots) and non-refugial (79 plots) sites sampled following the 2012...
Abstract (from https://link.springer.com/article/10.1007/s10980-017-0540-9): Context Quantitative models of forest dynamics have followed a progression toward methods with increased detail, complexity, and spatial extent. Objectives We highlight milestones in the development of forest dynamics models and identify future research and application opportunities. Methods We reviewed milestones in the evolution of forest dynamics models from the 1930s to the present with emphasis on forest growth and yield models and forest landscape models We combined past trends with emerging issues to identify future needs. Results Historically, capacity to model forest dynamics at tree, stand, and landscape scales was constrained...
Categories: Publication; Types: Citation; Tags: Forests, Landscapes, Northeast CASC
Abstract (from http://www.sciencedirect.com/science/article/pii/S143383191400105X): Floodplain forests are extremely productive for agriculture and historical floodplain forests have been converted to prime agricultural land throughout the world, resulting in disruption of ecosystem functioning. Given that flooding may increase with climate change and reforestation will increase resiliency to climate change, we tested whether reforested floodplains also have great potential to store carbon and the effects of even modest increases in forested acreage on carbon storage. To calculate potential aboveground biomass in the Lower Mississippi River Alluvial Valley (LMAV) of the United States, we determined current and historical...
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0294-1): Context Tree species distribution and abundance are affected by forces operating at multiple scales. Niche and biophysical process models have been commonly used to predict climate change effects at regional scales, however, these models have limited capability to include site-scale population dynamics and landscape-scale disturbance and dispersal. We applied a landscape modeling approach that incorporated three levels of spatial hierarchy (pixel, landtype, and ecological subsection) to model regional-scale shifts in forest composition under climate change. Objective To determine (1) how importance value of individual species will...
Greater sage-grouse (Centrocercus urophasianus) is a candidate for listing under the Endangered Species Act because of population and habitat fragmentation coupled with inadequate regulatory mechanisms to control development in critical areas. In addition to the current threats to habitat, each 1 degree celsius increase due to climate change is expected to result in an additional 87,000 km2 of sagebrush (Artemisia spp.) that will be converted to unsuitable habitat for sage-grouse. Thus, the future distribution and composition of sagebrush landscapes is likely to differ greatly from today’s configuration. We conducted a large, multi-objective project to identify: (1) characteristics of habitats required by sage-grouse,...
There is growing evidence that headwater stream ecosystems are especially vulnerable to changing climate and land use, but their conservation is challenged by the need to address the threats at a landscape scale, often through coordination with multiple management agencies and landowners. This project seeks to fill a gap, providing an example of cooperative landscape decision-making to address the conservation of headwater stream ecosystems in the face of climate change.
Urban forests provide well-documented environmental and societal benefits valued at more than four billion dollars per year in the United States. As cities expand onto land once occupied by rural forests, urban trees take on an even more vital role in mitigating global climate change, conserving biodiversity, and protecting human health. Maintaining the health of trees is challenging in cities and in forests under climate change because of tree stress and pests. Unhealthy trees do not provide adequate ecosystem services or conservation value compared to healthy trees. In this work we found that exotic trees can remain healthy and maintain biodiversity of arthropods (e.g. spiders and insects) that is similar to native...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/hyp.11144/full): The extensive forests that cover the mountains of the Pacific Northwest, USA, modify snow processes and therefore affect snow water storage as well as snow disappearance timing. However, forest influences on snow accumulation and ablation vary with climate, topography, and land cover and are therefore subject to substantial temporal and spatial variability. We utilize multiple years of snow observations from across the region to assess forest-snow interactions in the relatively warm winter conditions characteristic of the maritime and maritime-continental climates. We (1) quantify the difference in snow magnitude and disappearance timing...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2015WR017873/abstract): Spatially distributed snow depth and snow duration data were collected over two to four snow seasons during water years 2011–2014 in experimental forest plots within the Cedar River Municipal Watershed, 50 km east of Seattle, Washington, USA. These 40 × 40 m forest plots, situated on the western slope of the Cascade Range, include unthinned second-growth coniferous forests, variable density thinned forests, forest gaps in which a 20 m diameter (approximately equivalent to one tree height) gap was cut in the middle of each plot, and old-growth forest. Together, this publicly available data set includes snow depth and density observations...
Abstract (from http://www.publish.csiro.au/WF/WF16165): Interannual variability in burn severity is assessed across forested ecoregions of the western United States to understand how it is influenced by variations in area burned and climate during 1984–2014. Strong correlations (|r| > 0.6) between annual area burned and climate metrics were found across many of the studied regions. The burn severity of individual fires and fire seasons was weakly, but significantly (P < 0.05), correlated with burned area across many regions. Interannual variability in fuel dryness evaluated with fuel aridity metrics demonstrated weak-to-moderate (|r| >0.4) relationships with regional burn severity, congruent with but weaker than...
Snow conditions are extremely important to a wide range of hydrologic and ecosystem components and processes, including those related to surface energy and moisture stores and fluxes, vegetation, mammals, birds, and fish. The required snow datasets currently do not exist at the required spatial and temporal resolutions needed by end users such as scientists, land managers, and policy makers.
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/eap.1396/full): Extensive mortality of whitebark pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western US, primarily from mountain pine beetle but also from other threats such as white pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark pine mortality from mountain pine beetle are not well understood, yet are important considerations in whether to list whitebark pine as a threatened or endangered species. We sought to increase the understanding of climate influences on mountain pine beetle outbreaks in whitebark pine forests, which are less well understood...
Abstract (from http://www.hydrol-earth-syst-sci.net/21/1/2017/): The phase of precipitation when it reaches the ground is a first-order driver of hydrologic processes in a watershed. The presence of snow, rain, or mixed-phase precipitation affects the initial and boundary conditions that drive hydrological models. Despite their foundational importance to terrestrial hydrology, typical phase partitioning methods (PPMs) specify the phase based on near-surface air temperature only. Our review conveys the diversity of tools available for PPMs in hydrological modeling and the advancements needed to improve predictions in complex terrain with large spatiotemporal variations in precipitation phase. Initially, we review...
Abstract (from http://jcom.sissa.it/archive/15/01/JCOM_1501_2016_A01): Whereas the evolution of snow cover across forested mountain watersheds is difficult to predict or model accurately, the presence or absence of snow cover is easily observable and these observations contribute to improved snow models. We engaged citizen scientists to collect observations of the timing of distributed snow disappearance over three snow seasons across the Pacific Northwest, U.S.A. . The primary goal of the project was to build a more spatially robust dataset documenting the influence of forest cover on the timing of snow disappearance, and public outreach was a secondary goal. Each year's effort utilized a different strategy, building...
Public land managers face the daunting task of incorporating climate change vulnerability assessments into their land use planning. This NW CSC project developed decision support tools to guide resource managers through the process of including future climate projections, climate change vulnerability assessments, and adaptation response strategies and tactics into ongoing and existing planning efforts such as FS forest plan revisions and individual project plans. The tools were developed and tested through direct engagement with resource managers. The tools guide participants through a step-wise process that provides a structured framework to help managers (1) integrate climate projections with other local information...
Abstract (from http://www.bioone.org/doi/abs/10.3955/046.089.0305): It is hypothesized that climate impacts forest mosaics through dynamic ecological processes such as wildfires. However, climate-fire research has primarily focused on understanding drivers of fire frequency and area burned, largely due to scale mismatches and limited data availability. Recent datasets, however, allow for the investigation of climate influences on ecological patch metrics across broad regions independent of area burned and at finer scale. One area of particular interest is the distribution of fire refugia within wildfire perimeters. Although much recent research emphasis has been placed on high-severity patches within wildfires,...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0378112716308532): Across the western United States, the three primary drivers of tree mortality and carbon balance are bark beetles, timber harvest, and wildfire. While these agents of forest change frequently overlap, uncertainty remains regarding their interactions and influence on specific subsequent fire effects such as change in canopy cover. Acquisition of pre- and post-fire Light Detection and Ranging (LiDAR) data on the 2012 Pole Creek Fire in central Oregon provided an opportunity to isolate and quantify fire effects coincident with specific agents of change. This study characterizes the influence of pre-fire mountain pine beetle (MPB; Dendroctonus...