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A 36,200 cal yr B.P. vegetation history was developed from macrofossils and pollen from 55 packrat middens from 1287 to 1442 m elevation in the Peloncillo Mountains of southeasternmost Arizona, USA. Today, these elevations are dominated by semidesert grassland with a mixture of Chihuahuan and Sonoran Desert shrubs, including an eastern disjunct population of jojoba (Simmondsia chinensis). From 36,200 to 15,410 cal yr B.P., rocky areas just above large, pluvial lakes that occupied what are now dry playas supported Pinus edulis, Juniperus osteosperma, Juniperus cf. coahuilensis, Quercus cf. turbinella and a rich understory of summer-flowering C4 annuals and grasses, indicating abundant summer rains and mild winters....
1. Soil disturbance by animals affects the availability of water, nutrients, sediment and seeds, which are critical for the maintenance of functional ecosystems. We examined long-lived faunal structures across six vegetation communities in the northern Chihuahuan desert of New Mexico, USA, testing the proposition that disturbances in undesertified grassland differ in magnitude and effect from those in desertified grassland. 2. Vertebrate and invertebrate disturbances totalled 18.9 structures ha−1 across 18 sites. The most common were pits and mounds of American badgers (Taxidea taxus, 32%), nests of the ant Aphaenogaster cockerelli (18.8%) and mounds of kangaroo rats (Dipodomys spectabilis, 31%). 3. Desertification...
What are current conditions for important park natural resources? What are the critical data and knowledge gaps? What are some of the factors that are influencing park resource conditions? Natural Resource Condition Assessments (NRCAs) evaluate and report on the above for a subset of important natural resources in national park units (hereafter, parks). Focal study resources and indicators are selected on a park-by-park basis, guided by use of structured resource assessment and reporting frameworks. Considerations include park resource setting and enabling legislation (what are this park's most important natural resources?) and presently available data and expertise (what can be evaluated at this time?). In addition...
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Natural landscapes in the Southwestern United States are changing. In recent decades, rising temperatures and drought have led to drier conditions, contributed to large-scale ecological impacts, and affected many plant and animal species across the region. The current and future trajectory of climate change underscores the need for managers and conservation professionals to understand the impacts of these patterns on natural resources. In this regional assessment of the Southwest Climate Change Initiative, we evaluate changes in annual average temperatures from 1951–2006 across major habitats and large watersheds and compare these changes to the number of species of conservation concern that are found within these...
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A Vision for the Chihuahuan Desert The Chihuahuan Desert, shared by two nations, is one of the most biologically rich desert ecoregions in the world, alive with large mammals, birds, reptiles and an unmatched diversity of cactus species. The desert’s rivers, streams and springs are considered to be of global significance, home to fish species found nowhere else on earth. Our vision is a Chihuahuan Desert where governments, local communities, non-governmental organizations, academic institutions, landowners, and other stakeholders are working together to ensure that the richness and diversity of wildlife, habitats, natural communities, and ecological processes of the Chihuahuan Desert are conserved and, where necessary,...
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DLCC’s Vegetation Map Pilot is a project envisioned initially as a supervised classification of two or three small areas of the DLCC. DLCC technical stakeholders advised changing from a supervised classification to an object oriented classification (OOC) method.This report presents the findings, feasibility, and lessons-learned during the exploration and object oriented classification process and results of the two sites on the United States-Mexico border, this is needed information before considering a full-scale, Vegetation Mapping Project, to include bigger areas or the totality of the Desert LCC region.
Categories: Data; Tags: Academics & scientific researchers, Aquascalientes, Aquascalientes, Arizona, Arizona, All tags...
Drought and freezing are both known to limit desert plant distributions, but the interaction of these stressors is poorly understood. Drought may increase freezing tolerance in leaves while decreasing it in the xylem, potentially creating a mismatch between water supply and demand. To test this hypothesis, we subjected Larrea tridentata juveniles grown in a greenhouse under well-watered or drought conditions to minimum temperatures ranging from -8 to -24 �C. We measured survival, leaf retention, gas exchange, cell death, freezing point depression and leaf-specific xylem hydraulic conductance (k?). Drought-exposed plants exhibited smaller decreases in gas exchange after exposure to -8 �C compared to well-watered...
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The Sevilleta LTER supports a long-term, integrated, interdisciplinary research program addressing key hypotheses on pattern and process in aridland ecosystems. Sevilleta LTER research includes studies in desert grassland and shrubland communities, and riparian and mountain forests emphasizing pulse driven processes in space and time. Key drivers (e.g., climate, fire, water, resource availability) govern dynamics in each landscape component. Our focus on how biotic and abiotic drivers affect spatial and temporal dynamics of aridland ecosystems allows us to conduct long-term research that addresses important basic theories and yet has significant relevance to regional, national and international priorities. The...
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LandScope America—a collaborative project of NatureServe and the National Geographic Society—is a new online resource for the land-protection community and the public. By bringing together maps, data, photos, and stories about America’s natural places and open spaces, our goal is to inform and inspire conservation of our lands and waters.
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The Southwest Regional Gap Analysis Project (SWReGAP) is an update of the Gap Analysis Program’s mapping and assessment of biodiversity for the five-state region encompassing Arizona, Colorado, Nevada, New Mexico, and Utah. It is a multi-institutional cooperative effort coordinated by the U.S. Geological Survey Gap Analysis Program. The primary objective of the update is to use a coordinated mapping approach to create detailed, seamless GIS maps of land cover, all native terrestrial vertebrate species, land stewardship, and management status, and to analyze this information to identify those biotic elements that are underrepresented on lands managed for their long term conservation or are “gaps.”
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These heatmaps show a top 3 stressor or service, as ranked by participants, and the concentration of participants who reported as working in each municipality or county who also voted for that stressor or service across the landscape. This map shows the percentage of participants from each county and municipality who ranked Discharge of Untreated Wastewater as a top 3 ecosystem stressor in the Riparian Habitat Fragmentation and Lossl category in their region. Symbology represents the percentage of participants with 0% = dark green, 0.0001 % - 24.99% = light green, 25% - 49.99% = yellow, 50% - 74.99% = orange, 75% - 100% = red. All counties and municipalities identified by participants as areas where they work were...
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These bat location estimates have been reported by Bogan and others (In press) and come in the form of a GIS shape file. Three species of nectar-feeding phyllostomid bats migrate north from Mexico into deserts of the United States (U.S.) each spring and summer to feed on blooms of columnar cacti and century plants (Agave spp). However, the habitat needs of these important desert pollinators are poorly understood. We followed the nighttime movements of two species of long-nosed bats (Leptonycteris yerbabuenae and L. nivalis) in an area of late-summer sympatry at the northern edges of their migratory ranges. We radiotracked bats in extreme southwestern New Mexico during 22 nights over two summers and acquired location...
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The need to monitor change in sagebrush steppe is urgent due to the increasing impacts of climate change, shifting fire regimes, and management practices on ecosystem health. Remote sensing provides a cost-effective and reliable method for monitoring change through time and attributing changes to drivers. We report an automated method of mapping rangeland fractional component cover over a large portion of the Northern Great Basin, USA, from 1986 to 2016 using a dense Landsat imagery time series. 2012 was excluded from the time-series due to a lack of quality imagery. Our method improved upon the traditional change vector method by considering the legacy of change at each pixel. We evaluate cover trends stratified...
Tags: AZ, Arizona, Arizona Plateau, Black Hills, Blue Mountains, All tags...
State-and-transition models are increasingly being used to guide rangeland management. These models provide a relatively simple, management-oriented way to classify land condition (state) and to describe the factors that might cause a shift to another state (a transition). There are many formulations of state-and-transition models in the literature. The version we endorse does not adhere to any particular generalities about ecosystem dynamics, but it includes consideration of several kinds of dynamics and management response to them. In contrast to previous uses of state-and-transition models, we propose that models can, at present, be most effectively used to specify and qualitatively compare the relative benefits...
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The Sevilleta LTER supports a long-term, integrated, interdisciplinary research program addressing key hypotheses on pattern and process in aridland ecosystems. Sevilleta LTER research includes studies in desert grassland and shrubland communities, and riparian and mountain forests emphasizing pulse driven processes in space and time. Key drivers (e.g., climate, fire, water, resource availability) govern dynamics in each landscape component. Our focus on how biotic and abiotic drivers affect spatial and temporal dynamics of aridland ecosystems allows us to conduct long-term research that addresses important basic theories and yet has significant relevance to regional, national and international priorities. The...
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Grasslands of the Sky Islands region once covered over 13 million acres in southeastern Arizona and adjacent portions of New Mexico, Sonora, and Chihuahua. Attempts to evaluate current ecological conditions suggest that approximately two thirds of these remain as intact or restorable grassland habitat. These grasslands provide watershed services such as flood control and aquifer recharge across the region, and continue to support dozens of species of concern. Prioritizing conservation interventions for these remaining grassland blocks has been challenging. Reliable data on condition and conservation value of grasslands in the region have not been systematically summarized. State and national boundaries further complicate...
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The need to monitor change in sagebrush steppe is urgent due to the increasing impacts of climate change, shifting fire regimes, and management practices on ecosystem health. Remote sensing provides a cost-effective and reliable method for monitoring change through time and attributing changes to drivers. We report an automated method of mapping rangeland fractional component cover over a large portion of the Northern Great Basin, USA, from 1986 to 2016 using a dense Landsat imagery time series. 2012 was excluded from the time-series due to a lack of quality imagery. Our method improved upon the traditional change vector method by considering the legacy of change at each pixel. We evaluate cover trends stratified...
Tags: AZ, Arizona, Arizona Plateau, Black Hills, Blue Mountains, All tags...
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¿Por qué es importante para usted como ganadero preocuparse por las aves del pastizal? En términos prácticos, las aves del pastizal son indicadoras de la condición de sus potreros, ya que la abundancia de aves de pastizal le dice a usted que sus potreros están en buena condición para sostener su actividad productiva. Además, las aves del pastizal cumplen funciones que ayudan a mantener al ecosistema del pastizal. Aparte de los beneficios que proveen las aves del pastizal, éstas son parte de nuestro patrimonio natural y cultural que enriquecen la vida diaria de los habitantes de los pastizales mexicanos. Por este motivo, hemos elaborado este manual que contiene recomendaciones generales de manejo de pastizales para...
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Explore climate change impacts on vegetation across the Desert and Southern Rockies LCCs using historical monitoring data collected from 23 sites across the Sonoran, Chihuahuan, Mojave and Colorado Plateau deserts for 30-50 years. This data will then be combined with ecosystem water balance model simulations to establish features of water availability critical for plant species response. Results will allow managers to identify species and communities at risk under future climate scenarios based on predicted changes in plant water availability. Due to the high variability in soils, incorporating a detailed understanding of soil water availability beyond bioclimatic envelope approaches in the desert Southwest is essential...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, AZ-02, AZ-03, AZ-04, Academics & scientific researchers, All tags...


map background search result map search result map Impact of Ecosystem Water Balance on Desert Vegetation: Quantification of Historical Patterns and Projection under Climate Change LandScope America Southwest Regional Gap Analysis Project Natural Resource Condition Assessments Sevilleta GIS Vector Datasets Sevilleta LTER Sustaining the Grassland Sea Managing Changing Landscapes in the Southwestern United States Ecoregion-Based Conservation in the Chihuahuan Desert Compartiendo sus agostaderos con las aves de pastizal Radio telemetry data on nighttime movements of two species of migratory nectar-feeding bats (Leptonycteris) in Hidalgo County, New Mexico, late-summer 2004 and 2005 Vegetation Map Pilot Report Riparian - Habitat Fragmentation and Loss Stressors - Discharge of Untreated Wastewater Remote Sensing Shrub/Grass National Land Cover Database (NLCD) Back-in-Time (BIT) Annual Herbaceous Products for the Western U.S., 1985 - 2018 Remote Sensing Shrub/Grass National Land Cover Database (NLCD) Back-in-Time (BIT) Litter Products for the Western U.S., 1985 - 2018 Sevilleta LTER Radio telemetry data on nighttime movements of two species of migratory nectar-feeding bats (Leptonycteris) in Hidalgo County, New Mexico, late-summer 2004 and 2005 Sustaining the Grassland Sea Compartiendo sus agostaderos con las aves de pastizal Riparian - Habitat Fragmentation and Loss Stressors - Discharge of Untreated Wastewater Managing Changing Landscapes in the Southwestern United States Ecoregion-Based Conservation in the Chihuahuan Desert Southwest Regional Gap Analysis Project Vegetation Map Pilot Report Impact of Ecosystem Water Balance on Desert Vegetation: Quantification of Historical Patterns and Projection under Climate Change Remote Sensing Shrub/Grass National Land Cover Database (NLCD) Back-in-Time (BIT) Annual Herbaceous Products for the Western U.S., 1985 - 2018 Remote Sensing Shrub/Grass National Land Cover Database (NLCD) Back-in-Time (BIT) Litter Products for the Western U.S., 1985 - 2018 LandScope America Sevilleta GIS Vector Datasets Natural Resource Condition Assessments