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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....
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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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....
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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...
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...
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....
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...
Bouteloua gracilis (Kunth) Lag. ex Griffiths (blue grama), Bouteloua eriopoda (Torr.) Torr. (black grama), and Larrea tridentata Coville (creosotebush) are dominant plants on the McKenzie Flats portion of the Llano de Manzano landform within Sevilleta National Wildlife Refuge in central New Mexico, part of the biome ecotone from the Colorado Shortgrass Steppe to the Chihuahuan Desert. In this study, we examine the hypothesis that soil heterogeneity, determined by variation in surface soil depth, carbonate accumulation, and fine-textured fraction, controls relative dominance of the three species. The area is flat, generally <1% slope; however, abrupt soil differences exist even within the flattest parts of the landscape...
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....
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Seedlings of the succulent crassulacean acid metabolism (CAM plant Agave deserti in the northwestern Sonoran Desert were found only in sheltered microhabitats, nearly all occurring under the canopy of a desert bunchgrass, Hilaria rigida. Apparently because soil surface temperatures can reach 71@?C in exposed areas, seedlings were generally located near the center or on the northern side of this nurse plant. Both species have shallow root systems, about half of the roots of H. rigida and all those for seedlings of A. deserti occurring above soil depths of 0.08 m. To examine competition for water between the nurse plant and an associated seedling, a three-dimensional model for root water uptake was developed. The...
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 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....
Aeolian erosion of natural dust on two types of hills located in a rocky desert was investigated by means of wind tunnel simulations and field measurements. The first hill showed an elongated, nearly symmetric shape and was oriented perpendicular to the wind, whereas the second hill was almost perfectly conical. Erosion was measured along three transects: one across the elongated hill (transect parallel to the wind) and two across the conical hill (transects perpendicular to each other and crossing at the summit). In the field, erosion was measured on erosion plots during two wind storms. In the wind tunnel, erosion was measured on topographic scale models. The wind tunnel experiments and field experiments showed...
There may be no more conspicuous example of a conflict between society and technology than a wind energy landscape. The fastest growing renewable energy resource in the world, wind energy has evoked a cool public response. Through the use of interviews, the published literature, governing legislation, and personal experience, this article examines this conflict near Palm Springs, California. Its purpose is to summarize and explain the opposition that developed there from the earliest days, what has been done to mitigate it, and how the local experience is reflected in similar developments elsewhere. This particular conflict between society and technology has the potential, with proper guidance, controls, and sensitivity,...
Biological soil crusts (BSCs) are the dominant living cover in many drylands of the world. They possess many features that can influence different aspects of local hydrologic cycles, including soil porosity, absorptivity, roughness, aggregate stability, texture, pore formation, and water retention. The influence of biological soil crusts on these factors depends on their internal and external structure, which varies with climate, soil, and disturbance history. This paper presents the different types of biological soil crusts, discusses how crust type likely influences various aspects of the hydrologic cycle, and reviews what is known and not known about the influence of biological crusts on sediment production and...
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....
map background search result map search result map Controls of Bedrock Geochemistry on Soil and Plant Nutrients in Southeastern Utah Interactions Between Seedlings of Agave Deserti and the Nurse Plant Hilaria Rigida FSA 10:1 NAIP Imagery m_3511530_ne_11_1_20150528_20150923 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3511530_sw_11_1_20150528_20150923 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_3210655_nw_13_1_20141004_20141030 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3210655_sw_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 FSA 10:1 NAIP Imagery m_3511530_ne_11_1_20150528_20150923 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3511530_sw_11_1_20150528_20150923 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_3210655_nw_13_1_20141004_20141030 3.75 x 3.75 minute JPEG2000 from The National Map FSA 10:1 NAIP Imagery m_3210655_sw_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 Interactions Between Seedlings of Agave Deserti and the Nurse Plant Hilaria Rigida Controls of Bedrock Geochemistry on Soil and Plant Nutrients in Southeastern Utah