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The aim of this study was to determine if Arase dam gate removal and flushing elevated concentrations of any trace elements in Kuma River and Yatsushiro Bay sediments or caused riverine environmental change. The Arase dam gate on the Kuma River was opened in April 2010. Surface and bottom sediments were compared using 10-cm-long cores (2011) and two grain size fractions. Surface sediment data from 2002, 2012, and 2013 from the Kuma River and Yatsushiro Bay were also compared. The sediments were analyzed using XRF for 23 elements, and the grain size analysis was done. The short core surface and bottom sediments do not show major chemical changes, and therefore, may not represent post-and pre-dam sediments. Results...
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Stable isotopes of delta(18)O, delta(2)H, and (13)C, radiogenic isotopes of (14)C and (3)H, and ground water chemical compositions were used to distinguish ground water, recharge areas, and possible recharge processes in an arid zone, fault-bounded alluvial aquifer. Recharge mainly occurs through exposed stream channel beds as opposed to subsurface inflow along mountain fronts. This recharge distribution pattern may also occur in other fault-bounded aquifers, with important implications for conceptualization of ground water flow systems, development of ground water models, and ground water resource management. Ground water along the mountain front near the basin margins contains low delta(18)O, (14)C (percent modern...
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These data were compiled to evaluate the magnitude and direction of change from historical conditions in climate metrics across the Southeastern Utah Group (SEUG) of National Parks. Objective(s) of our study were to quantify the magnitude and direction of change from historical conditions in climate metrics across SEUG parks at a meaningful scale for land managers and practitioners. These data represent the historical and projected future average temperatures for two emission scenarios and 12 global circulation models. Included are the annual average temperatures and the average temperatures for each season. These data were created by sampling representative locations across each National Park unit and simulating...
Tags: Arches National Park, Botany, Canyonlands National Park, Climatology, Colorado Plateau, All tags...
Reciprocal selection pressures often lead to close and adaptive matching of traits in coevolved species. A failure of one species to match the evolutionary trajectories of another is often attributed to evolutionary lags or to differing selection pressures across a geographic mosaic. Here we show that mismatches in adaptation of interacting species–an obligate brood parasitic duck and each of its two main hosts–are best explained by the evolutionary dynamics within the host species. Rejection of the brood parasite's eggs was common by both hosts, despite a lack of detectable cost of parasitism to the hosts. Egg rejection markedly reduced parasite fitness, but egg mimicry experiments revealed no phenotypic natural...
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Pan evaporation is a measure of atmospheric evaporative demand (E0) for which long term and spatially distributed observations are available from the NOAA Cooperative Observer (COOP) Network. However, this data requires extensive quality control and homogenization due to documented and undocumented station moves and other factors including human errors in recording or digitization. Station-based Pan Evaporation measurements (in mm) from 247 stations across the continental United States were compiled and quality controlled for the analysis shown in Dewes et al., 2017. This dataset reports warm season (May-October; for 21 stations the data is only available for May-September) pan evaporation with at least 20 years...
Warming-induced release of CO2 from the large carbon (C) stores in arctic soils could accelerate climate change. However, declines in the response of soil respiration to warming in long-term experiments suggest that microbial activity acclimates to temperature, greatly reducing the potential for enhanced C losses. As reduced respiration rates with time could be equally caused by substrate depletion, evidence for thermal acclimation remains controversial. To overcome this problem, we carried out a cooling experiment with soils from arctic Sweden. If acclimation causes the reduction in soil respiration observed after experimental warming, then it should subsequently lead to an increase in respiration rates after cooling....
Stable isotope values of hydrogen and oxygen from precipitation and ground water samples were compared by using a volumetrically based mixing equation and stable isotope gradient to estimate the season and location of recharge in four basins. Stable isotopes were sampled at 11 precipitation sites of differing elevation during a 2-year period to quantify seasonal stable isotope contributions as a function of elevation. Supplemental stable isotope data collected by the International Atomic Energy Association during a 14-year period were used to reduce annual variability of the mean seasonal stable isotope data. The stable isotope elevation relationships and local precipitation elevation relationships were combined...
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Analysis of a typical semiarid mountain system recharge (MSR) setting demonstrates that geochemical tracers help resolve the location, rate, and seasonality of recharge as well as ground water flowpaths and residence times. MSR is defined as the recharge at the mountain front that dominates many semiarid basins plus the often-overlooked recharge through the mountain block that may be a significant ground water resource; thus, geochemical measurements that integrate signals from all flowpaths are advantageous. Ground water fluxes determined from carbon-14 ((14)C) age gradients imply MSR rates between 2 x 10(6) and 9 x 10(6) m(3)/year in the Upper San Pedro Basin, Arizona, USA. This estimated range is within an order...
Dust deposition to mountain snow cover, which has increased since the late 19(th) century, accelerates the rate of snowmelt by increasing the solar radiation absorbed by the snowpack. Snowmelt occurs earlier, but is decoupled from seasonal warming. Climate warming advances the timing of snowmelt and early season phenological events (e.g., the onset of greening and flowering); however, earlier snowmelt without warmer temperatures may have a different effect on phenology. Here, we report the results of a set of snowmelt manipulations in which radiation-absorbing fabric and the addition and removal of dust from the surface of the snowpack advanced or delayed snowmelt in the alpine tundra. These changes in the timing...
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Seasonal forages of desert bighorn sheep (Ovis canadensis nelsoni) were analyzed for dry matter, crude protein, in vitro digestibility, and cell wall content. Qualitative nutrient intake was estimated by combining chemical analyses with diet-composition data. Composite diets were also analyzed for the above parameters as well as for phosphorus and calcium. Dietary quality generally declined from spring to winter. Diet digestibility was good to excellent year-round, indicating that desert bighorn were receiving adequate energy. Protein levels were high in spring but were probably deficient for lactating ewes and young lambs in summer and fall. Diets were deficient in phosphorus in all seasons. Forbs had higher protein...
Wildland fire is a global phenomenon, and a result of interactions between climate?weather, fuels and people. Our climate is changing rapidly primarily through the release of greenhouse gases that may have profound and possibly unexpected impacts on global fire activity. The present paper reviews the current understanding of what the future may bring with respect to wildland fire and discusses future options for research and management. To date, research suggests a general increase in area burned and fire occurrence but there is a lot of spatial variability, with some areas of no change or even decreases in area burned and occurrence. Fire seasons are lengthening for temperate and boreal regions and this trend should...
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Current (2010's), Near-Term (2020's), and Long-Term (2060's) projected monthly snow-day fraction for winter and spring-seasons. These data are provided by Bureau of Land Management (BLM) "as is" and may contain errors or omissions. The User assumes the entire risk associated with its use of these data and bears all responsibility in determining whether these data are fit for the User's intended use. These data may not have the accuracy, resolution, completeness, timeliness, or other characteristics appropriate for applications that potential users of the data may contemplate. The User is encouraged to carefully consider the content of the metadata file associated with these data. The BLM should be cited as the data...
    map background search result map search result map Geochemical quantification of semiarid mountain recharge. Ground water recharge and flow characterization using multiple isotopes. Seasonal nutrition of desert Bighorn sheep in Canyonlands National Park, Utah BLM REA NOS 2012 Climate Change Figures C9 to C11 Climate and drought adaptation: historical and projected future exposure metrics for Southeastern Utah Group National Parks Geochemical quantification of semiarid mountain recharge. Seasonal nutrition of desert Bighorn sheep in Canyonlands National Park, Utah Climate and drought adaptation: historical and projected future exposure metrics for Southeastern Utah Group National Parks Ground water recharge and flow characterization using multiple isotopes. BLM REA NOS 2012 Climate Change Figures C9 to C11