SEARCH · Search USGS
Results for “Natural Areas Journal”
Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Extent and control of resource damage due to noncompliant visitor behavior: A case study from the U.S. National Parks
No abstract available.
Current research in land, water, and agroecosystems: ASABE journals 2017 year in review
This article highlights current research into land and water resources, agroecosystems, and agricultural production systems published by the Natural Resources and Environmental Systems (NRES) community of ASABE journals (Transactions of the ASABE and Applied Engineering in Agriculture) in 2017. This article reviews the context, scope, and key results of the published articles and perhaps more importantly recommends areas for increased research attention. Experimental and modeling advances were described in hydrology, agroecosystems, climate-change effects, soil erosion, irrigation, drainage, forest resources, livestock systems, natural treatment systems, international water issues, and water quality topic areas. Three special collections were published (International Watershed Technology, Crop Modeling to Optimize Water Use, and Advances in Drainage). Other focal areas included 14 articles relating to livestock waste management, 13 concerning irrigated agricultural systems, 8 addressing climate change effects on land and water resources, and 16 on various aspects of soil erosion measurement and modeling. Building on the articles reviewed from 2017 and toward a vision of future agroecosystems research, the NRES community of ASABE journals strives to grow its role in making new knowledge accessible to sustain agricultural and natural systems in a changing world. In this vane, recommendations for future research direction are discussed with an emphasis on increased application of remote sensing data to agroecosystems research, improved assessment of agroecosystem resiliency and vulnerability to land and climate change, development of integrated models of agroecosystem services, meeting stubborn water management challenges in agricultural production systems, and focusing on publishing fully reproducible model results.
Shorebird use of South Carolina managed and natural coastal wetlands
While many migrating and wintering shorebird (Charadriiformes) species face declines in quality and quantity of natural stopover sites, diked wetlands managed for shorebirds may provide supplemental habitat. We describe an integrative shorebird-waterfowl management strategy used at Tom Yawkey Wildlife Center on South Island, South Carolina, during 3 winter-spring seasons (1991-93). We compared shorebird use and invertebrate density between diked, managed wetlands and adjacent natural coastal mudflat areas. About 3,000 shorebirds overwintered each year at the site. Migration numbers peaked at 15,000-19,000 during late May. In 1991, shorebird density and absolute numbers were higher ( P < 0.05) in managed wetlands at high tide than natural mudflats at low tide. In 1993, we counted shorebird density at low tide both in managed wetlands and Mother Norton Shoals, the largest natural area. During February, shorebird frequency was higher in Mother Norton Shoals and lower in managed wetlands than expected values based on area ( P < 0.005). In contrast, from March to May, shorebird frequency was higher in managed wetlands and lower in natural mudflats than expected ( P < 0.005 for each month). Invertebrate density from March to May was generally greater in managed wetlands than at Mother Norton Shoals, which may explain shorebird preference during that time. Greater invertebrate density did not explain the pattern in February. Mean water depth in managed wetlands for each shorebird species was <5 cm except for American avocet ( Recurvirostra americana ) which used deeper water ( x̄ = 8.4 cm, SD = 4.5). Results indicate that an integrative shorebird-waterfowl management strategy provides supplemental shorebird habitat at high tide, and managed wetlands can be preferred to local natural mudflat areas at low tide.
Compensating for diminishing natural water: Predicting the impacts of water development on summer habitat of desert bighorn sheep
Artificial water sources have been used for decades to enhance and restore wildlife habitat but the benefits of their use have been subject to debate. During the past century, the number of natural springs in Joshua Tree National Park, California, USA, has declined. In response to concerns about the viability of the bighorn sheep (Ovis canadensis nelsoni) population, a number of water developments were constructed throughout the park. We modeled potential historical and present-day summer habitat of female bighorn sheep to evaluate the effectiveness of the artificial and remaining natural water sources in maintaining habitat and to determine how loss of artificial sources might affect future habitat availability. Prior to 1950, 583.5 km2 of summer habitat was potentially available. Presently, only 170.6 km2 of habitat is available around natural water sources and 153.5 km2 is available around guzzlers. When all perennial water sources are included in the habitat model (minus overlap), 302.3 km2 of summer habitat is potentially available. This represents only 51.7% of summer habitat available prior to 1950. Without artificial water developments, 47.7% of present-day summer habitat would be lost, which raises important management questions regarding the debate about what is natural or artificial within otherwise protected areas.
Non-native animals on public lands
Non-native plants and animals have become part of our surroundings, in cities, agricultural areas, and wildlands. While there are many beneficial purposes for non-native animals, such as for food and sport hunting and as agricultural animals, the introduction of some has had major negative economic consequences (Palmer 1899), and adverse effects on native wildlife, plants, and habitats. The British ecologist Charles Elton, in a major review of introduced species, described the increasing number of invasions as constituting "one of the great historical convulsions in the world's flora and fauna" (Elton 1958, p. 31). Non-native species are significant problems on large areas of state and federal public lands, and areas set aside to protect native plant and animal communities are not immune to such harm. Science and conservation journals have devoted entire issues to the threats posed by non-native plants and animals in nature reserves (e.g., Usher et al. 1988). In a compilation of threats to U.S. national parks, non-native plants and animals were the most often reported threat, and were reported by the most areas; feral cats ( Felis catus ), feral dogs ( Canis familiaris ), and wild pigs ( Sus scrofa ) were the non-native animals cited most often (NPCA 1977). Non-native species present serious threats, but at the same time, coordinated efforts on public lands offer the best possibility for controlling some harmful non-native species, and protecting both native plant and animal communities and human interests and needs. We compiled information on non-native animals on public and private land-management areas by conducting a mail survey to assess their occurrence and management status in land-management areas. Survey results represent contributions from 937 national parks, national forests, national wildlife refuges, Bureau of Land Management field areas, and state and private land-management areas. The results reflect those species that land managers considered of greatest concern, and their general distribution on public lands. Non-native invertebrate animals, particularly forest insects and agricultural pests, cause severe economic and environmental damage as well (OTA 1993), but were not the focus of this survey.
Use of artificially created Douglas-fir snags by cavity-nesting birds
In western Oregon, we created snags by sawing tops off live Douglas-fir ( Pseudotsuga menziesii ) (n = 821) trees and monitored their condition and use by cavity-nesting birds. We created snags in three silvicultural treatments: modified clearcut stands, two-story stands, and small-patch group-selection stands. We used two snag patterns: clumped and scattered. Created snags averaged 3.8/ha in density, 17 m in height, and 75 cm in diameter. Chainsaw-topped snags were used by cavity nesters within 5 yr of creation. Abundance of excavated cavities increased in all silvicultural treatments (P = 0.0001) and was higher in two-story and clearcut stands than in small-patch stands (P ≤ 0.0004). We did not, however, find that snag pattern (clumped v. scattered) affected use by cavity-nesting birds based on abundance of excavated cavities (P > 0.6). We observed excavated cavities in five hardwood species indicating that hardwoods represented an important resource for cavity-nesting birds. Creating conifer snags by topping and retaining hardwoods may retain or increase populations of cavity nesters in areas with low natural snag density.
A double-observer method for reducing bias in faecal pellet surveys of forest ungulates
1. Faecal surveys are used widely to study variations in abundance and distribution of forest-dwelling mammals when direct enumeration is not feasible. The utility of faecal indices of abundance is limited, however, by observational bias and variation in faecal disappearance rates that obscure their relationship to population size. We developed methods to reduce variability in faecal surveys and improve reliability of faecal indices. 2. We used double-observer transect sampling to estimate observational bias of faecal surveys of Roosevelt elk Cervus elaphus roosevelti and Columbian black-tailed deer Odocoileus hemionus columbianus in Olympic National Park, Washington, USA. We also modelled differences in counts of faecal groups obtained from paired cleared and uncleared transect segments as a means to adjust standing crop faecal counts for a standard accumulation interval and to reduce bias resulting from variable decay rates. 3. Estimated detection probabilities of faecal groups ranged from < 0.2-1.0 depending upon the observer, whether the faecal group was from elk or deer, faecal group size, distance of the faecal group from the sampling transect, ground vegetation cover, and the interaction between faecal group size and distance from the transect. 4. Models of plot-clearing effects indicated that standing crop counts of deer faecal groups required 34% reduction on flat terrain and 53% reduction on sloping terrain to represent faeces accumulated over a standard 100-day interval, whereas counts of elk faecal groups required 0% and 46% reductions on flat and sloping terrain, respectively. 5. Synthesis and applications. Double-observer transect sampling provides a cost-effective means of reducing observational bias and variation in faecal decay rates that obscure the interpretation of faecal indices of large mammal abundance. Given the variation we observed in observational bias of faecal surveys and persistence of faeces, we emphasize the need for future researchers to account for these comparatively manageable sources of bias before comparing faecal indices spatially or temporally. Double-observer sampling methods are readily adaptable to study variations in faecal indices of large mammals at the scale of the large forest reserve, natural area, or other forested regions when direct estimation of populations is problematic. ?? 2008 The Authors.
Distribution and transport of Olympia oyster, Ostrea lurida, larvae in northern Puget Sound, Washington, USA
As efforts for restoring Olympia oyster (Ostrea lurida) populations have expanded, there is an increased need to understand local factors that could influence the long-term success of these projects. To address concerns over potential limitations to recruitment at a restoration site in northern Puget Sound, Washington, USA, a study was developed to characterize physical processes governing larval transport in conjunction with larval abundance and environmental factors. Larval presence was not associated with tide cycle, season, or a combination of tide cycle and season. In terms of location, larvae were more likely to be present at offshore and intertidal sites versus the estuarine lagoon where the adult population resides. Larval density was higher during late summer ebbs versus early summer floods. Across sampling dates and locations, larval sizes ranged from 184 to 263 µm, indicating that larvae were released into the water column throughout the reproductive season and retained in the embayment for at least ~16 days. Throughout different tidal cycles in Skagit Bay, acoustic Doppler current profilers were used to measure current direction and velocities, concurrent with plankton sampling. Surface currents in the study area alternated between a clockwise and counterclockwise gyre during initial ebb and flood tides, respectively. Larvae exported from the source population during initial to mid-ebbs are swept into a northward gyre, and potentially retained at intertidal sites alongshore. These results will provide resource managers attempting to restore native bivalves with the ability to expand populations by identifying optimal areas for habitat enhancement through natural recruitment.
The web of life: Natural science information on the Internet
As society has come to equate economic prosperity with the health of our living resources, national science policy has called for the development of a comprehensive digital knowledge base to support informed decision making and wise resource management. The Internet and World Wide Web demonstrate the earliest stages of this evolving virtual library of the natural world, offering an increasing array of high-quality, innovative resources and services in the natural science arena. This article discusses the leading providers of natural science information on the Internet and highlights some of the exemplary resources they are delivering online. The discussion concludes with a brief discussion of the role of the librarian in developing the Web of natural science knowledge online and provides a short Webliography of starting points for further exploration of this subject area. PDF
Groundwater flow into Lake Michigan from Wisconsin
Detailed hydrogeological study has been done at six sites along the Lake Michigan shoreline in Wisconsin. At each site a flux of groundwater to the lake has been calculated for both natural conditions and the existing conditions created by pumping. The values from each site have then been extrapolated to the entire portion of the total shoreline having similar hydrogeology in order to calculate a total flow of groundwater to the lake. Sensitivity analysis with a digital model was used to define limits on the similarity of hydrogeologic conditions. The net flow calculated is 580–880 m 3 day −1 km −1 of shoreline, which falls within the previously published range of 110–8200 m 3 day −1 km −1 . Human activity may have reduced the natural flow as much as 15%. The estimated natural flow is between 7 and 11% of the surface water contribution to the lake from the study area.
Determining population size of territorial red-winged blackbirds
Population sizes of territorial male red-winged blackbirds ( Agelaius phoeniceus ) were determined with counts of territorial males (area count) and a Petersen-Lincoln Index method for roadsides (roadside estimate). Weather conditions and time of day did not influence either method. Combined roadside estimates had smaller error bounds than the individual transect estimates and were not hindered by the problem of zero recaptures. Roadside estimates were usually one-half as large as the area counts, presumably due to an observer bias for marked birds. The roadside estimate provides only an index of major changes in populations of territorial male redwings. When the roadside estimate is employed, the area count should be used to determine the amount and nature of observer bias. For small population surveys, the area count is probably more reliable and accurate than the roadside estimate.
What a drag: Quantifying the global impact of chronic bottom trawling on continental shelf sediment
Continental shelves worldwide are subject to intense bottom trawling that causes sediment to be resuspended. The widely used traditional concepts of modern sedimentary transport systems on the shelf rely only on estimates for naturally driven sediment resuspension such as through storm waves, bottom currents, and gravity-driven flows but they overlook a critical anthropogenic factor. The strong influence of bottom trawling on a source-to-sink sediment budget is explored on the NW Iberian shelf. Use of Automated Information System vessel tracking data provides for a high-resolution vessel track reconstruction and the accurate calculation of the spatial distribution of bottom trawling intensity and associated resuspended sediment load. The mean bottom trawling-induced resuspended sediment mass for the NW Iberian shelf is 13.50 Mt yr − 1 , which leads to a six-fold increase in off-shelf sediment transport when compared to natural resuspension mechanisms. The source-to-sink budget analysis provides evidence that bottom trawling causes a rapid erosion of the fine sediment on human time scales. Combining global soft sediment distribution data of the shelves with worldwide bottom trawling intensity estimates we show that the bottom trawling-induced resuspended sediment mass amounts to approximately the same mass of all sediment entering the shelves through rivers. Spatial delineations between natural and anthropogenic sediment resuspension areas are presented to aid in marine management questions.
Literature review for Texas Department of Transportation Research Project 0-4695: Guidance for design in areas of extreme bed-load mobility, Edwards Plateau, Texas
A review of the literature addressing sediment transport in gravel-bed river systems and structures designed to control bed-load mobility is provided as part of Texas Department of Transportation research project 0–4695: Guidance for Design in Areas of Extreme Bed-Load Mobility. The study area comprises the western half of the Edwards Plateau in central Texas. Three primary foci of the literature review are journal articles, edited volumes, and government publications. Major themes within the body of literature include deterministic sediment transport theory and equations, development of methods to measure and analyze fluvial sediment, applications and development of theory in natural channels and flume experiments, and recommendations for river management and structural design. The literature review provides an outline and foundation for the research project to characterize extreme bed-load mobility in rivers and streams across the study area. The literature review also provides a basis upon which potential modifications to low-water stream-crossing design in the study area can be made.
Magma intrusion and volatile ascent beneath Norris Geyser Basin, Yellowstone National Park
Recent activity has provided new insights into the causes of surface deformation in and around the Yellowstone Caldera, a topic that has been debated since the discovery of caldera floor uplift more than four decades ago. An episode of unusually rapid uplift (>15 cm/yr) centered near Norris Geyser Basin along the north caldera rim began in late 2013 and continued until a M w 4.9 earthquake on 30 March 2014; thereafter, uplift abruptly switched to subsidence. Uplift at rates of several centimeters per year resumed in 2016 and continued at least through the end of 2018. Modeling of Global Positioning System and interferometric synthetic aperture radar data suggests an evolving process of deep magma intrusion during 1996–2001 followed by volatile ascent and accumulation at shallow levels, perhaps as shallow as a few hundred meters depth. The depth of shallow volatile accumulation appears to have shallowed from the 2014 to the 2016 deformation episode, and frequent eruptions of Steamboat Geyser since March 2018 are likely a surface manifestation of this ongoing process. Hydrothermal explosion features are prominent in the Norris Geyser Basin area, and the apparent shallow nature of the volatile accumulation implies an increased risk of hydrothermal explosions.
Anthropogenic nitrogen deposition induces rapid ecological changes in alpine lakes of Colorado Front Range (USA)
Recent sediments from two alpine lakes (> 3300 m asl) in the Colorado Front Range (USA) register marked and near-synchronous changes that are believed to represent ecological responses to enhanced atmospheric deposition of fixed nitrogen from anthropogenic sources. Directional shifts in sediment proxies include greater representations of mesotrophic diatoms and increasingly depleted δ 15 N values. These trends are particularly pronounced since ~ 1950, and appear to chronicle lake responses to excess N derived from agricultural and industrial sources to the east. The rate and magnitude of recent ecological changes far exceed the context of natural variability, as inferred from comparative analyses of a long core capturingthe entire 14,000-year postglacial history of one of the lakes. Nitrogen deposition to these seemingly pristine natural areas has resulted in subtle but detectable limnological changes that likely represent the beginning of a stronger response to nitrogen enrichment.
Support for management actions to protect night sky quality: Insights from visitors to state and national park units in the U.S.
Light pollution is a global phenomenon where anthropogenic light sources continue to grow unabated, affecting both social and ecological systems. This is leaving parks and protected areas as some of the last vestiges of naturally dark environments for protecting views of the night sky. Yet, even parks and protected areas have outdoor lighting. Alternative lighting practices are needed to reduce or prevent light pollution from within parks. However, making parks darker may not be desirable for some visitors if they believe it will reduce navigability, safety, or restrict how they recreate (e.g., requiring the use of red-light flashlights after dark and before dawn). How visitors will respond to alternative lighting practices that park managers can implement is still unknown. We used an on-site intercept survey at nine state and national park units in Utah, U.S. , to investigate nighttime visitors' support or opposition to management actions to protect night sky quality and their interest in learning about topics related to night skies. Further, this study also segmented visitors into two groups: those ‘dependent’ on the dark sky as a resource and those whose activities did not depend on a dark sky. Defining what a ‘dark sky dependent’ visitor is, which has yet to be done in the literature, is a fundamental step to furthering night sky research and management efforts. Across nine parks and protected areas, 62% of nighttime visitors participated in dark sky dependent activities. Findings indicate broad support for management actions designed to improve night sky quality, with between 74% and 89% of all visitors supporting seven different management actions. There was stronger support from dark sky dependent visitors for some elements of alternative lighting practices, but there was still strong support for those who do not participate in dark sky dependent outdoor recreation. Additionally, between 57% and 75% of visitors were interested in learning more about topics related to night skies. This research indicates most visitors would welcome actions to preserve the quality of the rapidly dwindling naturally dark experiences offered by parks and protected areas.
State factor relationships of dissolved organic carbon and nitrogen losses from unpolluted temperate forest watersheds
We sampled 100 unpolluted, old-growth forested watersheds, divided among 13 separate study areas over 5 years in temperate southern Chile and Argentina, to evaluate relationships among dominant soil-forming state factors and dissolved carbon and nitrogen concentrations in watershed streams. These watersheds provide a unique opportunity to examine broad-scale controls over carbon (C) and nitrogen (N) biogeochemistry in the absence of significant human disturbance from chronic N deposition and land use change. Variations in the ratio dissolved organic carbon (DOC) to nitrogen (DON) in watershed streams differed by underlying soil parent material, with average C:N = 29 for watersheds underlain by volcanic ash and basalt versus C:N = 73 for sedimentary and metamorphic parent materials, consistent with stronger adsorption of low C:N hydrophobic materials by amorphous clays commonly associated with volcanic ash and basalt weathering. Mean annual precipitation was related positively to variations in both DOC (range: 0.2-9.7 mg C/L) and DON (range: 0.008-0.135 mg N/L) across study areas, suggesting that variations in water volume and concentration may act synergistically to influence C and N losses across dry to wet gradients in these forest ecosystems. Dominance of vegetation by broadleaf versus coniferous trees had negligible effects on organic C and N concentrations in comparison to abiotic factors. We conclude that precipitation volume and soil parent material are important controls over chemical losses of dissolved organic C and N from unpolluted temperate forest watersheds. Our results raise the possibility that biotic imprints on watershed C and N losses may be less pronounced in naturally N-poor forests than in areas impacted by land use change and chronic N deposition. Copyright 2007 by the American Geophysical Union.