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The National Geophysical Data Center (NGDC), a part of the National Oceanic and Atmospheric Administration, has been given the task of collecting, managing, and disseminating the great mass of inofmation produced by scientific observations of the geophysical environment. This article describes NGDC data bases that speifically relate to natural hazards.
The natural food habits of grizzly bears ( Ursus arctos horribilis Ord) in Yellowstone National Park were investigated in 1973-74 to identify the grizzly's energy sources and trophic level(s), nutrient use, and distribution. Food consumption was determined by scat analysis and field observations. Food quality and digestibility were estimated by chemical analysis. Grizzlies were distributed in 3 distinctive feeding economies: valley / plateau , a grass/rodent economy where grizzlies were intensive diggers; mountain , primarily a grass/springbeauty/root economy where grizzlies were casual diggers; and lake , primarily a fish/grass economy where grizzlies were fishers. The economies occurred in areas with fertile soils; distribution of bears within each was related to the occurrence of succulent plants. The feeding cycle in the valley/plateau and mountain economies followed plant phenology. Grizzlies fed primarily on meat before green-up and on succulent herbs afterwards; meat, corms, berries, and nuts became important during the postgrowing season. Succulent grasses and sedges with an importance value percentage of 78.5 were the most important food items consumed. Protein from animal tissue was more digestible than protein from plant tissue. Storage fats were more digestible than structural fats. Food energy and digestibility were directly related. Five principle nutrient materials (listed with their percentage digestibilities) contributed to total energy intake: protein from succulent herbs, 42.8; protein and fat from animal material, 78.1; fat and protein from pine nuts, 73.6; starch, 78.8; and sugar from berries and fruits, digestibility undetermined. Protein from succulent herbs, with a nutritive value percentage of 77.3, was the grizzlies' primary energy source. Because succulent, preflowering herbs had higher protein levels than dry, mature herbs, grizzly use of succulent herbs guaranteed them the highest source of herbaceous protein. Low protein digestibility of succulent herbs was compenstated for by high intake. Grizzlies were digestively flexible and maximized use of protein from plant and animal sources. They were adapted to the most constant and abundant sources of protein: succulent herbs and animal material from open, fertile grasslands. Competition among grizzlies for animal food during the pregrowing season may be regulatory for the grizzly population. The grizzly population level can be partially accounted for by the grizzlies' status as secondary consumers during pregreen-up periods and primary consumers during the growing and postgrowing seasons. The essential environmental requirement was the availability of fertile grasslands and herblands interspersed with cover and capable of maintaining artiodactyls, rodents, and abundant nutritious herbs as sources of food.
The more that is learned of the chemistry of aquatic natural organic matter (NOM) the greater is the scientific appreciation of the vast complexity of this subject. This complexity is due not only to a multiplicity of precursor molecules in any environment but to their associations with each other and with other components of local environments such as clays, mineral acids and dissolved metals. In addition, this complex system is subject to constant change owing to environmental variables and microbial action. Thus, there is a good argument that no two NOM samples are exactly the same even from the same source at nearly the same time. When ubiquity of occurrence, reaction with water treatment chemicals, and subsequent human exposure are added to the list of NOM issues, one can understand the appeal that this subject holds for a wide variety of environmental scientists.
Large populations live on or near alluvial fans in locations such as Los Angeles, California, Salt Lake City, Utah, Denver, Colorado, and lesser known areas such as Sarno, Italy, and Vargas, Venezuela. Debris flows and flash floods occur episodically in these alluvial fan environments, and place many communities at high risk during intense and prolonged rainfall. In December 1999, rainstorms induced thousands of landslides along the Cordillera de la Costa, Vargas, Venezuela. Rainfall accumulation of 293 mm during the first 2 weeks of December was followed by an additional 911 mm of rainfall on December 14 through 16. Debris flows and floods inundated coastal communities resulting in a catastrophic death toll of as many as 30,000 people. Flash floods and debris flows caused severe property destruction on alluvial fans at the mouths of the coastal mountain drainage network. In time scales spanning thousands of years, the alluvial fans along this Caribbean coastline are dynamic zones of high geomorphic activity. Because most of the coastal zone in Vargas consists of steep mountain fronts that rise abruptly from the Caribbean Sea, the alluvial fans provide practically the only flat areas upon which to build. Rebuilding and reoccupation of these areas requires careful determination of hazard zones to avoid future loss of life and property. KEY TERMS: Debris flows, flash floods, alluvial fans, natural hazards, landslides, Venezuela
Natural resource agencies make decisions involving public resources in which the public, by definition, have a stake. These resources are often finite. Thus, different viewpoints, interests, or beliefs may conflict when parties are perceived to be interdependent or one party is perceived to block or oppose other parties' use of a scarce resource. These confl icts may occur regard less of whether there are any real differences between the parties or whether one party's actions actually affect the other (Thomas 1992; Robbins 1994; Appelbaum et al. 1999). Conflicts are defined here as "a process of social interaction involving a struggle over claims to resources, power and status, beliefs, and other preferences and desires" (Appelbaum et al. 1999, 63). Such conflicts can occur at multiple stages or levels of decisionmaking and can be embedded within other conflicts.
The San Francisco Estuary has undergone dramatic changes since the Gold Rush, as both natural forces and human activities have added and removed massive quantities of sediment, primarily sand and mud. A long-term perspective of sediment movement and patterns of sediment deposition and erosion is vital for effective management of wetlands, sediment contamination, dredging, mining, and other phenomena. Quantitative analysis of historical depth surveys and changes between surveys provides this perspective.
The Upper Klamath Basin (UKB) in northern California and southern Oregon supports large hypereutrophic lakes surrounded by natural and artificial shorelines. Lake shorelines contain fringe wetlands that provide key ecological services to the people of this region. These wetlands also provide a context for drawing inferences about how differing wetland types and wave exposure contribute to the vegetative assemblages in lake-fringe wetlands. Here, we summarize how elevation profiles and vegetation richness vary as a function of wave exposure and wetland type. Our results show that levee wetland shorelines are 4X steeper and support fewer species than other wetland types. We also summarize the occurrence probability of the five common wetland plant species that represent the overwhelming majority of the diversity of these wetlands. In brief, the occurrence probability of the culturally significant Nuphar lutea spp. polysepala and the invasive Phalaris arundinacea in wave exposed and sheltered sites varies based on wetland type. The occurrence probability for P. arundinacea was greatest in exposed portions of deltaic shorelines, but these trends were reversed on levees where the occurrence probability was greater in sheltered sites. The widespread Schoenoplectus acutus var. acutus occurred throughout all wetland and exposure type combinations but had a higher probability of occurrence in wave exposed sites. Results from this work will add to our current understanding of how wetland shoreline profiles interact with wave exposure to influence the occurrence probability of the dominant vegetative species in UKB’s shoreline wetlands.
Amphibian population declines are not limited to overly degraded habitats, but often occur in relatively pristine environments such as national parks or wildlife refuges, thus forcing biologists to examine less obvious causes for declines such as the presence of contaminants. The objective of our study was to extract naturally-occurring compounds from amphibian habitats (using semipermeable membrane devices) in three national parks or wildlife refuges (two sites within Sequoia Kings Canyon National Park, Big Bend National Park, and Kenai National Wildlife Refuge), and assess their toxicity to developing larvae using bioassays. Extracts did not cause mortality, so all effects observed were sublethal, influencing life history characteristics. In all three areas studied, amphibians reared in extracts from at least one of the two sites exhibited either a lengthened larval period or reduced mass at metamorphosis. Extracts from both the air and water at one site in Sequoia Kings Canyon National Park lengthened the larval period, which is in agreement with studies showing elevated levels of aerially transported contaminants at sites such as this within the park. Ultraviolet radiation, which is also suspected of having caused amphibian declines and was included as a factor in our study, did not act alone or alter the toxicity of the extracts.
The latest cutting-edge research on flood pulsing and wetland restoration in North America. Presenting the latest research from leaders in the field of restoration ecology, Flood Pulsing in Wetlands reflects the current movement to incorporate flood pulsing into wetland restoration efforts. Emphasizing how integral flood pulsing is to successful wetland restoration, the book's contributors provide descriptions of restoration projects across North America in which flood pulsing has been primarily used to restore beneficial hydrodynamic conditions to floodplain areas, and improve or save vegetation, wildlife, and terrain. Detailing the importance and applicability of recreating flood-pulsed conditions on floodplains for successful restoration, the first chapter introduces the concept of flood pulse and its unique role in wetland restoration. The following chapters detail the strategies and results of individual projects and the impact flood pulsing had on the projects' overall goals. Case studies detail the history of each region, such as the Southwest, including the Sonoran Desert communities and the Middle Rio Grande; the Missouri River in Montana; the Illinois River Valley; and the Southeast, including Brushy Lake, Arkansas. Also documented is the most famous case of flood pulsing used in the restoration of an entire landscape, the Kissimmee River project. Approaches used to restore specific plant and animal populations, the unique ecological concerns of each region, and the future outlook for each area are fully described. Extensive bibliographies for each chapter make Flood Pulsing in Wetlands: Restoring the Natural Hydrological Balance the essential reference for restoration ecologists, consultants in wetland restoration, government and restoration agency employees, land managers, ecologists, foresters, and geologists.
Natural disasters and their consequences dominate the news almost on a daily basis. Quick-impact preventive and aid measures are essential for the victims to survive. This volume presents a selection of projects which demonstrate impressively how both cutting-edge technology and locally available materials and resources can be used for this purpose.
The purpose of this chapter is to provide a summary of issues and findings related to the potential effects of coalbed natural gas (CBNG) development on fish and other aquatic resources. We reviewed CBNG issues from across the United States and used the Powder River Basin of Wyoming as a case study to exemplify some pertinent issues. The quality of water produced during CBNG extraction is quite variable. High total dissolved solids in many CBNG produced waters are of concern relative to fish and other aquatic organisms. Untreated CBNG produced water has the potential to be toxic to fish and aquatic organisms. Of particular concern at some locations in the Powder River basin are elevated concentrations of sodium bicarbonate which have been shown to be toxic to some species of larval fish and aquatic invertebrates. The areas affected by direct toxicity were limited to headwaters and small tributaries studied in the basin. The potential effects of organic compounds used during well drilling and CBNG production on water quality, fish, and aquatic organisms are not well defined. Water produced from CBNG wells that is low in salts or has been treated to remove salts may be discharged into ephemeral or perennially-flowing streams. Higher flows in small streams can enhance erosion and affect habitat for fish and aquatic organisms. In Great Plains rivers, such as the Powder River, fish and aquatic invertebrate communities are structured by extreme environmental conditions. Direct discharge of CBNG produced water during periods of very low or no surface flow may cause shifts in the aquatic community structure. Additional effects of CBNG development on fish and aquatic organisms may stem from road building and pipeline construction, roads crossing streams and ephemeral water courses, the possible spread of invasive organisms, potential spills of toxic substances, and increased harvest of sport fish.
The purpose of this chapter is to provide a summary of issues and findings related to the potential effects of coalbed natural gas (CBNG) development on fish and other aquatic resources. We reviewed CBNG issues from across the United States and used the Powder River Basin of Wyoming as a case study to exemplify some pertinent issues. The quality of water produced during CBNG extraction is quite variable. High total dissolved solids in many CBNG produced waters are of concern relative to fish and other aquatic organisms. Untreated CBNG produced water has the potential to be toxic to fish and aquatic organisms. Of particular concern at some locations in the Powder River basin are elevated concentrations of sodium bicarbonate which have been shown to be toxic to some species of larval fish and aquatic invertebrates. The areas affected by direct toxicity were limited to headwaters and small tributaries studied in the basin. The potential effects of organic compounds used during well drilling and CBNG production on water quality, fish, and aquatic organisms are not well defined. Water produced from CBNG wells that is low in salts or has been treated to remove salts may be discharged into ephemeral or perennially-flowing streams. Higher flows in small streams can enhance erosion and affect habitat for fish and aquatic organisms. In Great Plains rivers, such as the Powder River, fish and aquatic invertebrate communities are structured by extreme environmental conditions. Direct discharge of CBNG produced water during periods of very low or no surface flow may cause shifts in the aquatic community structure. Additional effects of CBNG development on fish and aquatic organisms may stem from road building and pipeline construction, roads crossing streams and ephemeral water courses, the possible spread of invasive organisms, potential spills of toxic substances, and increased harvest of sport fish.
The time frame for natural attenuation of crude oil contamination in the subsurface has been studied for the last 27 years at a spill site located near Bemidji, Minnesota, USA. Data from the groundwater contaminant plume show that dissolved benzene concentrations adjacent to the oil decreased by 50% between 1993 and 2007. To assess how this decrease is related to benzene concentrations in the crude oil, samples of oil were bailed from floating oil in five wells and analysed for volatile components. Compared to reference oil collected from the pipeline in 1984, benzene concentrations in the well located farthest downgradient in the oil have decreased an average of 50%. Benzene and ethylbenzene depletion are linearly correlated with oil saturation in the pore space suggesting that dissolution is the primary removal mechanism and biodegradation within the oil body is insignificant.
Describes the topic of natural resource and ecosystem costs of coastal hazards through the work of the John Heinz III Center for Science, Economics and the Environment.
A study is underway to apply machine learning methods to evaluate natural resource potential. In particular, we are considering the search for blind geothermal systems in Nevada. Beginning with the data and experience from the previous Nevada play fairway analysis project, we are building models in TensorFlow/Keras and gaining experience toward predicting the geothermal resource potential as a probability map. During the first year of this project we have encountered several issues particular to using geological and geophysical data sets with these tools. Through an illustrative example we develop a promising workflow for future use as more data become available and are analyzed.
The goal of this project was to facilitate climate change adaptation that contributes to social-ecological resilience, ecosystem and species conservation, and sustainable human communities in southwestern Colorado. The team developed and piloted integrated adaptation planning tools and principles that merge the strengths of the iterative scenario process, the Adaptation for Conservation Targets (ACT) planning framework, institutional analysis, and climate modeling. These tools and principles generated practical strategies and scientific knowledge to advance climate change adaptation in both the Gunnison River Basin and San Juan River Basin and, potentially, other landscapes. A key objective of this project was to work with decision-makers to develop social-ecological adaptation strategies and coordinate actions to reduce the impacts of a changing climate on nature and people. To accomplish this, the project blended science (biophysical and social) and participatory approaches to integrate expert knowledge, land management decision making, and local needs. These adaptation strategies and their creation process were documented by the project team to assist communities and scientists elsewhere who are grappling with the challenges posed by climate change.
Migration of leachate from a municipal landfill in Saco, Maine has resulted in arsenic concentrations in ground water as high as 647 μg/L . Laboratory experimental data indicate the primary source of arsenic to be reductive dissolution of arsenic-enriched iron oxyhydroxides in the aquifer by organic carbon in landfill leachate. A core from an uncontaminated part of the aquifer yielded no dissolved iron or arsenic when leached with oxic ground water. Eluent ground water spiked with organic carbon in order to create reducing conditions mobilized both ferrous iron and arsenite from this core. The landfill was capped in early 1998 to eliminate the source of leachate. Cores from the contaminated portion of the aquifer were collected and leached with uncontaminated ground water in the laboratory to simulate natural remediation conditions. Data from these experiments show that significant concentrations of labile organic carbon have accumulated on aquifer solids, causing significant biological oxygen demand. In laboratory leaching experiments of the most contaminated core, the organic carbon caused complete consumption of the influent dissolved oxygen (6 mg/L) for 220 pore volumes. Arsenic leaching from contaminated cores rapidly decreased in concentration initially in response to flushing with uncontaminated ground water. Subsequent leaching produced more gradual decreases in dissolved arsenic concentrations, controlled by a combination of reductive dissolution of arsenic-enriched iron oxyhydroxides and adsorption/desorption. In leachate from the most contaminatedcore, arsenic concentrations exceeded the new United States Environmental Protection Agency drinking-water standard of 10 μg/L for more than 200 pore volumes. A geochemical model simulated the concentration of selected constituents as uncontaminated ground water eluted through contaminated aquifer solids. Concentrations of dissolved oxygen, arsenic, and iron, in leachate from one core were used to calibrate the model. This model was validated by successfully simulating constituent concentrations in leachate from cores collected from other contaminated areas of this aquifer.
Without a comprehensive understanding of nekton use of key habitats across locations, natural resource managers and restoration practitioners in the northern Gulf of Mexico region lack a key tool to assist in their efforts to design, implement, and monitor effective coastal restoration and protection efforts in the decades to come. To address this need, Abt helped conduct a systematic literature review, data compilation, and meta-analysis to evaluate nekton use of estuarine habitats in the northern Gulf of Mexico.