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Community energy initiatives offer a potentially important means for reshaping the electrical system in a manner compatible with emissions reduction goals. Many such initiatives, however, focus upon top-down, institutionally structured approaches that understand community residents as atomistic, economically motivated, and minimally engaged. This paper examines a number of case studies that are based upon a bottom-up approach rooted in a civic culture that seeks to maximize the capacities of an active and engaged citizenry. The paper focuses upon two mutually dependent issues: first, recruiting community members, and second, sustaining their participation.
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At recent technical conferences, many coal geoscientists in academia and government institutions as well as in industry organizations have expressed concern about the dwindling number of students and young staff members interested in careers in coal geoscience. To better understand what is driving these trends and to identify potential ways that the community can increase interest and participation in coal geoscience, two different surveys were sent to 94 coal geoscientists who were current or past members of The Society of Organic Petrology (TSOP) in February 2020. As the trends and perceptions in industry and government organizations may be different than in universities, one distinct survey was sent to members...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0380133014002597): Fish stock-recruitment dynamics may be difficult to elucidate because of nonstationary relationships resulting from shifting environmental conditions and fluctuations in important vital rates such as individual growth or maturation. The Great Lakes have experienced environmental stressors that may have changed population demographics and stock-recruitment relationships while causing the declines of several prey fish species, including rainbow smelt (Osmerus mordax). We investigated changes in the size and maturation of rainbow smelt in Lake Michigan and Lake Huron and recruitment dynamics of the Lake Michigan stock over the past...
Community energy initiatives offer a potentially important means for reshaping the electrical system in a manner compatible with emissions reduction goals. Many such initiatives, however, focus upon top-down, institutionally structured approaches that understand community residents as atomistic, economically motivated, and minimally engaged. This paper examines a number of case studies that are based upon a bottom-up approach rooted in a civic culture that seeks to maximize the capacities of an active and engaged citizenry. The paper focuses upon two mutually dependent issues: first, recruiting community members, and second, sustaining their participation.
Abstract (from http://www.srmjournals.org/doi/abs/10.2111/REM-D-13-00079.1): Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified...
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These data consist of environmental covariates, measured plot-level and tree characteristics for seven coniferous tree species across the southwestern United States. The objectives of the study were to assess how growth characteristics of conifer tree species vary across environmental gradients and across the different tree species. These data represent conifer growth under a variety of stand and site characteristics. These data were collected in the summer of 2019, from sites across Nevada, Arizona, New Mexico and Colorado, and collected by field crews directed by Matt Petrie (University of Nevada Las Vegas), Rob Hubbard (USDA Forest Service), Tom Kolb (Northern Arizona University) and John Bradford (U.S. Geological...
Categories: Data; Tags: Arizona, Botany, California, Climatology, Colorado, All tags...
Invasion by nonnative brook trout (Salvelinus fontinalis) often results in replacement of cutthroat trout (Oncorhynchus clarki) in the inland western United States, but the underlying mechanisms are not well understood. We conducted a four-year removal experiment to test for population-level mechanisms (i.e., changes in recruitment, survival, emigration, and immigration) promoting invasion success of brook trout and causing decline of native Colorado River cutthroat trout (O. c. pleuriticus). We chose 700–1200 m segments of four small mountain streams where brook trout had recently invaded cutthroat trout populations, two each at mid elevation (2500–2700 m) and high elevation (3150–3250 m), and annually removed...
Flannelmouth sucker, Catostomus latipinnis, a fish endemic to the Colorado River basin in the western United States, appears to experience poor recruitment to adult size in the Colorado River, downstream of Glen Canyon Dam. Lack or impermanence of rearing areas for young-of-year (YOY) fish is hypothesized to be the problem. Knowing the importance of tributary mouths as rearing areas in other river systems, we studied use of the mouth of the Paria River, a tributary of the Colorado River, by YOY flannelmouth suckers, and the availability of rearing area in the mouth at different flow levels in the Colorado River in 1996 and 1997. We also examined the relationship between flash floods in the Paria River and catch-per-unit-effort...
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Data set includes water Sr:Ca, Ba:Ca, and δ18O for the Mississippi River and tributaries, and otolith Sr:Ca, Ba:Ca, and δ18O data from bigheaded carp (Silver Carp and BIghead Carp) collected in navigation pools 16-19 of the Upper Mississippi River in 2016 to 2018. Bigheaded carp (Bighead Carp and Silver Carp) are invasive species in the US and have spread throughout most of the lower Mississippi River Basin. Population abundance upstream of Lock and Dam 19 (LD19) on the Upper Mississippi River (UMR) has likely been limited by the high-head dam at this location, which restricts all upstream fish passage to the lock chamber. To determine early-life environments of adult bigheaded carp captured upstream LD19 at the...
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These data were compiled to help understand how climate change may impact dryland pinyon-juniper ecosystems in coming decades, and how resource management might be able to minimize those impacts. Objective(s) of our study were to model the demographic rates of PJ woodlands to estimate the areas that may decline in the future vs. those that will be stable. We quantified populations growth rates across broad geographic areas, and identified the relative roles of recruitment and mortality in driving potential future changes in population viability in 5 tree species that are major components of these dry forests. We used this demographic model to project pinyon-juniper population stability under future climate conditions,...
Categories: Data; Tags: Arizona, Botany, California, Colorado, Ecology, All tags...
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Increasing temperatures and decreasing precipitation threaten the persistence of the Rio Grande cutthroat trout, the southernmost subspecies of cutthroat trout, found only in parts of New Mexico and Colorado. This subspecies appears to be more vulnerable to drought than more northern subspecies, because it occupies small and fragmented streams which are at greater risk of drying up during drought. Most notably, in 2002 drought in the Southwest resulted in the loss of 14 different Rio Grande cutthroat trout populations – about 10% of the total population. While it is known that drought is having an effect on Rio Grande cutthroat trout, the specific ways in which individuals and populations are affected by drought...
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In 2016, for the first time, an abundance of age-0 silver carp (Hypophthalmichthys molitrix) were captured at several sites upstream of Lock and Dam 19 on the Upper Mississippi River near Keokuk, Iowa. These data were collected in an attempt to determine the early life environments and frequency and timing of the reproductive events that led to a large year class of age-0 silver carp. This information is important for informing decisions about control measures. We sampled these fish to determine age (days) and early life environments using their otoliths. Sampled age-0 silver carp were collected from navigation Pools 18 and 19 from July–October 2016 using a variety of sampling gears. We aged these fish by counting...
In the shortgrass steppe region of North America there is a controversy about the ability of the dominant species to recruit from seedlings. The prevailing view is that Bouteloua gracilis is incapable of recruitment from seedlings in areas receiving <380 mm of annual precipitation. A common explanation for this situation is that environmental conditions permitting seedling establishment are infrequent. To assess the frequency of environmental conditions appropriate for the recruitment of B. gracilis we used a soil water simulation model and long-term climatic data in conjunction with detailed information about the ecophysiological requirements for seed germination and growth of seminal and adventitious roots. We...
Flow regulation effects on floodplain forests in the semi-arid western United States are moderately well understood, whereas effects associated with changes in floodplain land use are poorly documented. We mapped land cover patterns from recent aerial photos and applied a classification scheme to mainstem alluvial floodplains in 10 subjectively selected 4th order hydrologic units (subbasins) in the Upper Colorado River Basin (UCRB) in order to document land use patterns (floodplain development) and assess their effects on Fremont cottonwood forest (CF) regeneration. Three of the mainstem rivers were unregulated, five were moderately regulated and two were highly regulated. We classified polygons as Undeveloped (with...
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San Francisco Bay and Estuary is largely urbanized and developed, and the southern bay is the most urbanized with many sources of nutrients, many concerns that the system might become eutrophic, and many questions about how South Bay has maintained its relatively good health. The hypotheses for why South Bay is not eutrophic, where other bays have not been so fortunate, include high bivalve grazing that limits net phytoplankton growth and high turbidity which also limits the phytoplankton growth rate. Understanding the bivalve grazing rates in the south bay includes the necessity of understanding temporal and spatial distributions of bivalves. Despite the critical need to understand all controls on eutrophication,...
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Sagebrush ecosystems and wildlife that depend on them are under pressure from development, changing climate, as well as natural and human-caused disturbance. Mule deer (Odocoileus hemionus) are of particular concern due to population declines across many western states. We initiated a study to evaluate landscape-level changes ( disturbances, habitat treatments, development, and climate change) in Wyoming. This dataset contains age ratios (the number of juveniles to adult female mule deer) for 36 herd units in Wyoming, USA from 1985-2019. Age ratios provide a consistent metric of population demographics, including an index of recruitment (survival rate of young), which can be a sensitive metric of population change....
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Phytoplankton is an important and limiting food source in the Sacramento-San Joaquin Delta and San Francisco Bay; the decline of phytoplankton biomass is one possible factor in the pelagic organism decline and specifically in the decline of the protected delta smelt. The bivalves Corbicula fluminea and Potamocorbula amurensis (hereafter Corbicula and Potamocorbula, respectively) have been shown to control phytoplankton biomass in several locations throughout the system, and their distribution and population dynamics are therefore of great interest. As one element of the California Department of Water Resources (DWR) and the U.S. Bureau of Reclamation’s (BOR) Environmental Monitoring Program (EMP), the Generalized...
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Population growth and decline are particularly sensitive to changes in three key life-history parameters: annual productivity, juvenile survival, and adult survival. However, for many species these parameters remain unknown. For example, although grassland songbirds are imperiled throughout North America, for this guild, only a small number of studies have assessed these parameters. From 2002 to 2006, in the agricultural landscape of the Champlain Valley of Vermont and New York, USA, we studied Savannah Sparrow (Passerculus sandwichensis) and Bobolink (Dolichonyx oryzivorus) demography on four grassland treatments: (1) early-hayed fields cut before 11 June and again in early- to mid-July; (2) middle-hayed fields...
Community energy initiatives offer a potentially important means for reshaping the electrical system in a manner compatible with emissions reduction goals. Many such initiatives, however, focus upon top-down, institutionally structured approaches that understand community residents as atomistic, economically motivated, and minimally engaged. This paper examines a number of case studies that are based upon a bottom-up approach rooted in a civic culture that seeks to maximize the capacities of an active and engaged citizenry. The paper focuses upon two mutually dependent issues: first, recruiting community members, and second, sustaining their participation.
Community energy initiatives offer a potentially important means for reshaping the electrical system in a manner compatible with emissions reduction goals. Many such initiatives, however, focus upon top-down, institutionally structured approaches that understand community residents as atomistic, economically motivated, and minimally engaged. This paper examines a number of case studies that are based upon a bottom-up approach rooted in a civic culture that seeks to maximize the capacities of an active and engaged citizenry. The paper focuses upon two mutually dependent issues: first, recruiting community members, and second, sustaining their participation.
map background search result map search result map Grassland songbird survival and recruitment in agricultural landscapes: implications for source-sink demography. The Effects of Drought on Rio Grande Cutthroat Trout: The Role of Stream Flow and Temperature Results from surveys to academic and industry and government geoscientists on the future of coal geoscientists A spatially and temporally intensive sampling study of benthic community and bivalve metrics in the Sacramento-San Joaquin Delta (ver. 2.0, May 2021) Otolith microchemistry of adult bigheaded carp for determining early-life environments in the Upper Mississippi River 2016-2018 Otolith microchemistry and microstructure of age-0 silver carp for determining early-life environments and spawning periodicity in the Upper Mississippi River in 2016 Benthic Communities as Mediators of Water Quality in Lower San Francisco Bay, California (2012-2019) Pinyon-juniper basal area, climate and demographics data from National Forest Inventory plots and projected under future density and climate conditions Age ratios and landscape change covariates for mule deer (Odocoileus hemionus) herd units in Wyoming, USA, 1985-2019 Site characterization and regeneration attributes of managed and unmanaged ponderosa pine sites in the southwestern United States Benthic Communities as Mediators of Water Quality in Lower San Francisco Bay, California (2012-2019) Otolith microchemistry and microstructure of age-0 silver carp for determining early-life environments and spawning periodicity in the Upper Mississippi River in 2016 Otolith microchemistry of adult bigheaded carp for determining early-life environments in the Upper Mississippi River 2016-2018 The Effects of Drought on Rio Grande Cutthroat Trout: The Role of Stream Flow and Temperature Age ratios and landscape change covariates for mule deer (Odocoileus hemionus) herd units in Wyoming, USA, 1985-2019 Pinyon-juniper basal area, climate and demographics data from National Forest Inventory plots and projected under future density and climate conditions Site characterization and regeneration attributes of managed and unmanaged ponderosa pine sites in the southwestern United States Results from surveys to academic and industry and government geoscientists on the future of coal geoscientists