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NatureServe worked with several federal, state, and NGO partners in the United States and Mexico to conduct a climate change vulnerability assessment of major natural community types found within the Mojave and Sonoran Deserts. The project focused on ten major upland, riparian, and aquatic community types, including pinyon-juniper woodlands, Joshua tree-blackbrush scrub, creosote-bursage scrub, salt desert scrub, Paloverde-mixed cacti scrub, semi-desert grassland, desert riparian and stream, riparian mesquite bosque, and desert springs. This effort piloted a new Habitat Climate Change Vulnerability Index (HCCVI) approach being developed by NatureServe, as a companion to an existing index for species. The project...
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This shapefile represents habitat suitability categories (High, Moderate, Low, and Non-Habitat) derived from a composite, continuous surface of sage-grouse habitat suitability index (HIS, created using ArcGIS 10.2.2) values for Nevada and northeastern California during spring, which is a surrogate for habitat conditions during the sage-grouse breeding and nesting period.
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This raster represents a continuous surface of sage-grouse habitat suitability index (HSI) values for Nevada. HSIs were calculated for spring, summer, and winter sage-grouse seasons, and then multiplied together to create this composite dataset.
This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA). Test methods were developed for the use of clams to investigate the effects of sediment amendment on biological uptake. Sediment was mixed with activated carbon for one month. Bioaccumulation tests (28 d) were employed to assess the relationships between carbon dose and carbon particle size on observed reductions in clam biological uptake of PCBs. Extraction and cleanup protocols were developed for the clam tissue. Efficacy of activated carbon treatment was found to increase...
A common misperception about oil politics is that it has a uniform, monolithic effect on policy development. This paper argues that in fact the net political effect of oil varies dramatically depending on the nature of the petrostate. It shows that oil income, when combined with revolutionary governments in petrostates, generates strong incentives for foreign policy aggression and international conflict. The aggressiveness of petro-revolutionary states is shown to have consequences in both military and economic spheres of international relations. Militarily, the aggressiveness of this type of state leads to a high rate of armed conflicts. Economically, the aggressiveness of petro-revolutionary states shapes global...
Fire risk in deserts is increased by high production of annual forbs and invasive grasses that create a continuous fine fuel bed in the interspaces between shrubs. Interspace production is influenced by water, nitrogen (N) availability, and soil texture, and in some areas N availability is increasing due to anthropogenic N deposition. The DayCent model was used to investigate how production of herbaceous annuals changes along gradients of precipitation, N availability, and soil texture, and to develop risk-based critical N loads. DayCent was parameterized for two vegetation types within Joshua Tree National Park, California, USA: creosote bush (CB) and pi�on?juniper (PJ). The model was successfully calibrated in...
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Landscape Conservation Cooperatives (LCCs) are public-private partnerships composed of states, tribes, federal agencies, non-governmental organizations, universities, international jurisdictions, and others working together to address landscape and seascape scale conservation issues. LCCs inform resource management decisions to address broad-scale stressors-including habitat fragmentation, genetic isolation, spread of invasive species, and water scarcity-all of which are magnified by a rapidly changing climate. For further information go to https://www.fws.gov/science/catalog. The previous 2011 LCC Network Areas data is available at https://www.sciencebase.gov/catalog/item/52f2735ee4b0a6f0bd498c2f
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Landscape Conservation Cooperatives (LCCs) are public-private partnerships composed of states, tribes, federal agencies, non-governmental organizations, universities, international jurisdictions, and others working together to address landscape and seascape scale conservation issues. LCCs inform resource management decisions to address broad-scale stressors-including habitat fragmentation, genetic isolation, spread of invasive species, and water scarcity-all of which are magnified by a rapidly changing climate. For further information go to https://www.fws.gov/science/catalog. The previous 2011 LCC Network Areas data is available at https://www.sciencebase.gov/catalog/item/52f2735ee4b0a6f0bd498c2f
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Executive Summary: We provide an analysis of Sonoran Desert water network connectivity to inform managers of current conditions for target wildlife and how the connectivity will change as the landscape becomes more water limited.Climate change is expected to lead to fragmentation of the network, increasing coalescence distance by 8% and reducing the persistence and overall number of waters on the landscape. Identification of key water sites, ranked by network connectivity metrics, are presented in Appendix B. Wetland number under our scenario of water limitation will decline by 43% reducing network resilience.Anurans and Caudates, although varying in ability to disperse, generally experienced reduced connectivity...
“The loss of foundational but fire-intolerant perennials such as sagebrush due to increases in fire size and frequency in semi-arid regions has motivated efforts to restore them, often with mixed or even no success. Seeds of sagebrush Artemisia tridentata and related species must be moved considerable distances from seed source to planting sites, but such transfers have not been guided by an understanding of local climate adaptation. Initial seedling establishment and its response to weather are a key demographic bottleneck that likely varies among subspecies and populations of sagebrush.We assessed differences in survival, growth and physiological responses of sagebrush seedlings to weather among eleven seed sources...
Bromus species – such as cheatgrass – are exotic annual grasses that have become the dominant annual grasses in the western hemisphere. Their spread and impacts across the western United States continue despite the many attempts by land managers to control these species. A new book edited by scientists from the U.S. Geological Survey, U.S. Forest Service and Colorado State University answers critical research, planning, and management questions about these species. The book synthesizes available literature on the biology, ecology, sociology and economics of Bromus grasses to develop a more complete picture of the factors that influence their invasiveness, impacts, and management in the western United States. Lessons...
A common misperception about oil politics is that it has a uniform, monolithic effect on policy development. This paper argues that in fact the net political effect of oil varies dramatically depending on the nature of the petrostate. It shows that oil income, when combined with revolutionary governments in petrostates, generates strong incentives for foreign policy aggression and international conflict. The aggressiveness of petro-revolutionary states is shown to have consequences in both military and economic spheres of international relations. Militarily, the aggressiveness of this type of state leads to a high rate of armed conflicts. Economically, the aggressiveness of petro-revolutionary states shapes global...
Wind farms in South East Australia are unlikely to supply any significant power output that system operators can rely upon. Wind farms will load the distribution system with sudden variations in power that are not currently predictable and are as significant as the random variations of user demand.
Worldwide, many species are responding to ongoing climate change with shifts in distribution, abundance, phenology, or behavior. Consequently, natural-resource managers face increasingly urgent conservation questions related to biodiversity loss, expansion of invasive species, and deteriorating ecosystem services. We argue that our ability to address these questions is hampered by the lack of explicit consideration of species’ adaptive capacity (AC). AC is the ability of a species or population to cope with climatic changes and is characterized by three fundamental components: phenotypic plasticity, dispersal ability, and genetic diversity. However, few studies simultaneously address all elements; often, AC is confused...
Understanding local and geographic factors influencing species distributions is a prerequisite for conservation planning. Our objective in this study was to model local and geographic variability in elevations occupied by native and nonnative trout in the northwestern Great Basin, USA. To this end, we analyzed a large existing data set of trout presence (5,156 observations) to evaluate two fundamental factors influencing occupied elevations: climate-related gradients in geography and local constraints imposed by topography. We applied quantile regression to model upstream and downstream distribution elevation limits for each trout species commonly found in the region (two native and two nonnative species). With...
Quaking aspen (Populus tremuloides Michx.) is the most widespread tree species in North America, and it is found throughout much of the Mountain West (MW) across a broad range of bioclimatic regions. Aspen typically regenerates asexually and prolifically after fire, and due to its seral status in many western conifer forests, aspen is often considered dependent upon disturbance for persistence. In many landscapes, historical evidence for post-fire aspen establishment is clear, and following extended fire-free periods senescing or declining aspen overstories sometimes lack adequate regeneration and are succeeding to conifers. However, aspen also forms relatively stable stands that contain little or no evidence of...
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​Abstract: Climate change predictions include warming and drying trends, which are expected to be particularly pronounced in the southwestern United States. In this region, grassland dynamics are tightly linked to available moisture, yet it has proven difficult to resolve what aspects of climate drive vegetation change. In part, this is because it is unclear how heterogeneity in soils affects plant responses to climate. Here, we combine climate and soil properties with a mechanistic soil water model to explain temporal fluctuations in perennial grass cover, quantify where and the degree to which incorporating soil water dynamics enhances our ability to understand temporal patterns, and explore the potential consequences...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, AZ-02, AZ-03, AZ-04, Academics & scientific researchers, All tags...
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Article Introduction: Efforts to define water needs for riparian and aquatic ecosystems in arid and semi-arid systems are critical because riparian areas are essential for the survival of desert life, with stream corridors providing a large proportion of ecosystem services in these landscapes (Poff, Koestner, Neary, & Henderson, 2011; Millennium Ecosystem Assessment, 2005). To create a one-stop-shop for published ecological water needs information and illuminate critical knowledge gaps in the desert watersheds of the U.S. and Mexico, the University of Arizona’s Water Resources Research Center and the Northern Arizona University School of Earth Sciences and Environmental Sustainability created the Desert Flows Database....
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Aquascalientes, Arizona, Baja California, California, Chihuahua, All tags...
We show how land use and potential climate changes occurring in sagebrush communities in the Great Basin of North America are affecting the pygmy rabbit, a sagebrush obligate species. We revisited 105 sites where pygmy rabbits were collected before 1950 and determined the current presence of the species using infrared-triggered camera surveys. Pygmy rabbits were present at 36% of the sites. Fourteen percent of the sites showed signs of pinyon?juniper woodland encroachment, with only one of these sites still harboring pygmy rabbits. Sites also showed current evidence of fires (16%), urbanization (13%), and agricultural conversion (6%). At a local scale, fire frequency reduction due to livestock grazing and fire suppression...
Primary ecosystem services provided by freshwater wetlands in the California Central Valley, USA, include water quality improvement, biodiversity support, and flood storage capacity. We describe these services for freshwater marshes, vernal pools, and riparian wetlands and the implications for wetlands restored under USDA programs in the Central Valley. California's Central Valley is a large sedimentary basin that was once covered by grasslands, extensive riparian forests, and freshwater marshes that today have been converted to one of the most intensive agricultural areas on earth. Remaining freshwater wetlands have been heavily altered, and most are intensively managed. Nitrogen loading from agriculture to surface...
map background search result map search result map Climate Change Vulnerability and Adaptation Strategies for Natural Communities Spring Season Habitat Categories Shapefile Composite Habitat Suitability Index raster dataset Understanding Environmental Flows in Desert Rivers of the U.S. and Mexico through the Desert Flows Database Publication and Report: Ecosystem Water Balance in a Desert Grassland Quantitative and Predictive Analysis: Landscape Connectivity of Isolated Waters for Wildlife in the Sonoran Desert Quantitative and Predictive Analysis: Landscape Connectivity of Isolated Waters for Wildlife in the Sonoran Desert Spring Season Habitat Categories Shapefile Composite Habitat Suitability Index raster dataset Climate Change Vulnerability and Adaptation Strategies for Natural Communities Understanding Environmental Flows in Desert Rivers of the U.S. and Mexico through the Desert Flows Database Publication and Report: Ecosystem Water Balance in a Desert Grassland