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The deserts of the Southwest are under increasing pressure from growing human populations for land development - for cities, agriculture, livestock grazing, transportation and utility corridors, power plants, military activities, mining, and recreation. While some anthropogenic activities were initiated in the mid-1800s and have continued to present day, others are relatively new. The cumulative effects of historic and recent anthropogenic activities on natural resources have been both local and regional in scope. In addition, natural processes, such as local weather and global climate change, exert important influences on the landscape.
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The cold deserts of the Colorado Plateau contain numerous geologically and geochemically distinct sedimentary bedrock types. In the area near Canyonlands National Park in Southeastern Utah, geochemical variation in geologic substrates is related to the depositional environment with higher concentrations of Fe, Al, P, K, and Mg in sediments deposited in alluvial or marine environments and lower concentrations in bedrock derived from eolian sand dunes. Availability of soil nutrients to vegetation is also controlled by the formation of secondary minerals, particularly for P and Ca availability, which, in some geologic settings, appears closely related to variation of CaCO3 and Ca-phosphates in soils. However, the results...
This dataset is the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3800 observations representing 27 temperature manipulation studies, spanning nine biomes and nearly two decades of warming experiments. Data for this study were obtained from a combination of unpublished data and published literature values. We find that although warming increases soil respiration rates, there is limited evidence for a shifting respiration response with experimental warming. We also note a universal decline in the temperature sensitivity of respiration at soil temperatures >25°C. This dataset includes 3817 observations, from control (n=1812), first (i.e., lowest or sole) level...
Carbon and nitrogen are supplied by a variety of sources in the desert food web; both vascular and non-vascular plants and cyanobacteria supply carbon, and cyanobacteria and plant-associated rhizosphere bacteria are sources of biological nitrogen fixation. The objective of this study was to compare the relative influence of vascular plants and biological soil crusts on desert soil nematode and protozoan abundance and community composition. In the first experiment, biological soil crusts were removed by physical trampling. Treatments with crust removed had fewer nematodes and a greater relative ratio of bacterivores to microphytophages than treatments with intact crust. However, protozoa composition was similar with...
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The National Forest Management Act (NFMA) of 1976 requires every national forest or grassland managed by the U.S. Forest Service to develop and maintain a Land and Resource Management Plan (often referred to as a forest plan). The forest plan is the principle long-range guidance document for each forest or grassland, providing direction for project and activity decision making. Forest plans articulate goals and objectives, the kinds of uses that are suitable for areas of a national forest, management standards and guidelines that apply to different kinds of activities, and the designation of special areas like Research Natural Areas. Forest plans are strategic in nature and do not compel any action or authorize...
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This data set contains imagery from the National Agriculture Imagery Program (NAIP). The NAIP program is administered by USDA FSA and has been established to support two main FSA strategic goals centered on agricultural production. These are, increase stewardship of America's natural resources while enhancing the environment, and to ensure commodities are procured and distributed effectively and efficiently to increase food security. The NAIP program supports these goals by acquiring and providing ortho imagery that has been collected during the agricultural growing season in the U.S. The NAIP ortho imagery is tailored to meet FSA requirements and is a fundamental tool used to support FSA farm and conservation programs....
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This data set contains imagery from the National Agriculture Imagery Program (NAIP). The NAIP program is administered by USDA FSA and has been established to support two main FSA strategic goals centered on agricultural production. These are, increase stewardship of America's natural resources while enhancing the environment, and to ensure commodities are procured and distributed effectively and efficiently to increase food security. The NAIP program supports these goals by acquiring and providing ortho imagery that has been collected during the agricultural growing season in the U.S. The NAIP ortho imagery is tailored to meet FSA requirements and is a fundamental tool used to support FSA farm and conservation programs....
This data set contains imagery from the National Agriculture Imagery Program (NAIP). The NAIP program is administered by USDA FSA and has been established to support two main FSA strategic goals centered on agricultural production. These are increase stewardship of America's natural resources while enhancing the environment, and to ensure commodities are procured and distributed effectively and efficiently to increase food security. The NAIP program supports these goals by acquiring and providing ortho imagery that has been collected during the agricultural growing season in the U.S. The NAIP ortho imagery is tailored to meet FSA requirements and is a fundamental tool used to support FSA farm and conservation programs....
Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californicus, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed...
Greenhouse experiments were undertaken to identify soil factors that curtail growth of the exotic annual grass Bromus tectorum L. (cheatgrass) without significantly inhibiting growth of native perennial grasses (here represented by Hilaria jamesii [Torr.] Benth). We grew B. tectorum and H. jamesii alone (monoculture pots) and together (combination pots) in soil treatments that manipulated levels of soil phosphorus, potassium, and sodium. Hilaria jamesii showed no decline when its aboveground biomass in any of the applied treatments was compared to the control in either the monoculture or combination pots. Monoculture pots of B. tectorum showed a decline in aboveground biomass with the addition of Na2HPO4 and K2HPO4....
Archaea are common and abundant members of biological soil crust communities across large-scale biogeographic provinces of arid North America. Regardless of microbial community development, archaeal populations averaged 2 � 107 16S rRNA gene copies per gram of soil, representing around 5% of the prokaryotic (total calculated bacterial and archaeal) numbers assessed by quantitative-PCR. In contrast, archaeal diversity, determined by denaturing gradient gel electrophoresis fingerprinting and clone libraries of 16S rRNA genes, was very restricted. Only six different phylotypes (all Crenarchaea) were detected, three of which were very dominant. Some phylotypes were widespread, while others were typical of Southern desert...
The cold deserts of the Colorado Plateau contain numerous geologically and geochemically distinct sedimentary bedrock types. In the area near Canyonlands National Park in Southeastern Utah, geochemical variation in geologic substrates is related to the depositional environment with higher concentrations of Fe, Al, P, K, and Mg in sediments deposited in alluvial or marine environments and lower concentrations in bedrock derived from eolian sand dunes. Availability of soil nutrients to vegetation is also controlled by the formation of secondary minerals, particularly for P and Ca availability, which, in some geologic settings, appears closely related to variation of CaCO3 and Ca-phosphates in soils. However, the results...
The aeolian accumulation of natural atmospheric dust in a desert environment was investigated during a 24-month experiment. Accumulation was measured with marble collectors every month. At the same time, wind speed, dust concentration, dew formation and rainfall were recorded. Atmospheric stability was measured from a 90 m tower several km from the test site. Dust accumulation by day was systematically higher than dust accumulation at night. Also, dust concentration was higher, but the higher concentrations cannot completely explain die higher accumulation values. Both average monthly concentration and accumulation are considerably influenced by the occurrence of high-magnitude dust events, either dust storms or...
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Percent of ecoregion area covered with desert and aridland habitat. We derived the aridlands map by first developing a raster-based mask of arid climates from the Köppen-Geiger climate classification (Kottek et al. 2006) using ArcInfo GIS software. We applied the mask to the GLC 2000 global land cover, and then extracted sparse vegetation classes. For example, pockets of forested land occurring within Köppen-Geiger arid climate regions were excluded. Areas of human habitation and infrastructure were also removed from the map, leaving only natural desert lands. Finally, we applied a zonal sum procedure to the raster map to calculate the percentage of arid land per ecoregion. These data were derived by The Nature...


map background search result map search result map Controls of Bedrock Geochemistry on Soil and Plant Nutrients in Southeastern Utah Percent Aridland Area by Terrestrial Ecoregion Map of Centroid Consolidated Mines Group Plat of T7N R12W Showing Centroid Consolidated Mines Group United States Department of Agriculture Forest Service Southwestern Region Plan Revision FSA 10:1 NAIP Imagery m_3210655_ne_13_1_20141004_20141030 3.75 x 3.75 minute JPEG2000 from The National Map USGS 1:24000-scale Quadrangle for Desert, UT 1969 USGS 1:24000-scale Quadrangle for Desert, NM 1955 USGS 1:62500-scale Quadrangle for Desert, NM 1943 FSA 10:1 NAIP Imagery m_3911062_nw_12_1_20160722_20161017 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3911062_sw_12_1_20160722_20161017 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3210655_ne_13_1_20141004_20141030 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3911062_nw_12_1_20160722_20161017 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3911062_sw_12_1_20160722_20161017 3.75 x 3.75 minute JPEG2000 from The National Map USGS 1:24000-scale Quadrangle for Desert, UT 1969 USGS 1:24000-scale Quadrangle for Desert, NM 1955 USGS 1:62500-scale Quadrangle for Desert, NM 1943 Controls of Bedrock Geochemistry on Soil and Plant Nutrients in Southeastern Utah United States Department of Agriculture Forest Service Southwestern Region Plan Revision Percent Aridland Area by Terrestrial Ecoregion