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At least 1,207 records · Page 67Linked to original sources

Science to support adaptive habitat management: Overton Bottoms North Unit, Big Muddy National Fish and Wildlife Refuge, Missouri

Extensive efforts are underway along the Lower Missouri River to rehabilitate ecosystem functions in the channel and flood plain. Considerable uncertainty inevitably accompanies ecosystem restoration efforts, indicating the benefits of an adaptive management approach in which management actions are treated as experiments, and results provide information to feed back into the management process. The Overton Bottoms North Unit of the Big Muddy National Fish and Wildlife Refuge is a part of the Missouri River Fish and Wildlife Habitat Mitigation Project. The dominant management action at the Overton Bottoms North Unit has been excavation of a side-channel chute to increase hydrologic connectivity and to enhance shallow, slow current-velocity habitat. The side-channel chute also promises to increase hydrologic gradients, and may serve to alter patterns of wetland inundation and vegetation community growth in undesired ways. The U.S. Geological Survey's Central Region Integrated Studies Program (CRISP) undertook interdisciplinary research at the Overton Bottoms North Unit in 2003 to address key areas of scientific uncertainty that were highly relevant to ongoing adaptive management of the site, and to the design of similar rehabilitation projects on the Lower Missouri River. This volume presents chapters documenting the surficial geologic, topographic, surface-water, and ground-water framework of the Overton Bottoms North Unit. Retrospective analysis of vegetation community trends over the last 10 years is used to evaluate vegetation responses to reconnection of the Overton Bottoms North Unit to the river channel. Quasi-experimental analysis of cottonwood growth rate variation along hydrologic gradients is used to evaluate sensitivity of terrestrial vegetation to development of aquatic habitats. The integrated, landscape-specific understanding derived from these studies illustrates the value of scientific information in design and management of rehabilitation projects.

Missouri↗

Proceedings of preparing for a significant central United States earthquake: Science needs of the response and recovery community

Imagine waking up at 2 o'clock in the morning by a violent rumbling that causes ceilings to fall, furniture to topple over, and windows to break. Your home is crumbling, it is dark, and by the time you realize what is going on the shaking stops. You quickly determine that your family members are okay, but you also realize your power is out, all the windows are broken, and there is substantial damage to your home possibly making it unsafe to remain inside. The temperature outside is in the 20s, there is a heavy snow on the ground, and the flu season is at its peak with two of your family members affected. Unfortunately your family is one of thousands in a similar circumstance and the response to your needs may not be immediate, if at all. Could an earthquake like this happen unannounced? It did in the Central United States during the great New Madrid earthquake of 1811-12. A resident of New Madrid, Missouri writes (Martin, 1848 ): 'On the 16th of December 1811, about 2 o'clock, AM, we were visited by a violent shock of an earthquake accompanied by a very awful noise resembling loud but distant thunder, but more hoarse and vibrating, which was followed in a few minutes by the complete saturation of the atmosphere with sulphurious vapor, causing total darkness. The screams of the affrighted inhabitants running to and fro, not knowing where to go, or what to do-the cries of the fowls and beasts of every species-the crackling of trees falling, and the roar of the Mississippi-the current of which was retrograde for a few minutes, owing as is supposed to an irruption in its bed-formed a scene truly horrible.' Eliza Bryan, March 22, 1816 The residents of the Central United States during the great New Madrid earthquake were accustomed to living rugged life styles. Electrical power was not a reality, water was drawn from shallow hand-dug wells or retrieved from streams, food was hunted or grown, and the homes typically were log structures with dirt floors. Though these inhabitants were primitive by today's standards, they could survive because they did not rely on the supporting infrastructure we rely on today. What would you do if such an event struck as you read this? As a society, are we prepared for a similar event? Could you live for an extended period without power, refrigeration, heat, air conditioning, or fresh water? Missouri and its adjacent states have experienced more than 450 recorded earthquakes greater than magnitude 3 since 1964 (Petersen and others, 2008); however, none of these Central United States earthquakes has been as severe as the 1811-12 event. The 1811-12 events actually were a series of three very large earthquakes followed by many smaller but significant aftershocks (Johnston and Schweig, 1984). Ground shaking was reported as far away as Pittsburgh, Pennsylvania, and Charleston, South Carolina.

Scientific Investigations Report↗

Using visualization science to inform the design of environmental decision-support tools—A case study of the U.S. Geological Survey Waterwatch

Environmental decision-support tools are increasingly being used to serve both expert and non-expert audiences. Many existing tools are primarily expert-focused, and redesigning them can be challenging because experts and non-experts interact with tools differently, existing users may be resistant to changes, and there is little guidance on how to prioritize redesign efforts and demonstrate their efficacy. In this report, we present a case study of a user-centered redesign of an established environmental decision-support tool—the U.S. Geological Survey WaterWatch. WaterWatch supports flood, drought, and other water resource management decisions through the display of water levels at gages across the United States. Using a participatory process, we identified a functional change (replacing the existing rainbow colormap), created an alternative design, and tested the alternative’s usability through two general public surveys. The results showed that replacing the rainbow colormap with a more intuitive diverging colormap improves usability, regardless of the audience’s subjective preference for the rainbow color scheme. In addition, we demonstrated the importance of using legends to improve the audience’s understanding of the map symbols. This study demonstrates how user-centered design approaches can be used to inform the design of high-profile products and tools.

Scientific Investigations Report↗

Selected papers in the hydrologic sciences 1984; July 1984

The rapid, accurate measurement of the oxygen content of soil gas in the unsaturated zone or dissolved oxygen in soil water in the saturated zone can be useful in wetland vegetation studies. A method has been devised and tested in the Great Dismal Swamp, a wetland with fine silt-clay and organic soils, that appears to provide good results. A 60-milliliter sample of soil gas or water is withdrawn from permanently installed chambers at various depths in the soil profile. The oxygen concentration of air samples is measured with a specially constructed analyzer cell fitted to the polarographic oxygen electrode of a portable oxygen meter. The dissolved oxygen concentration of water samples is measured directly with the oxygen electrode while stirring the sample in a 32-milliliter glass bottle with a portable magnetic stirrer. Field tests with duplicate chamber installations showed that consistent results are obtained for soil gas and water.

Water Supply Paper↗

Selected papers in the hydrologic sciences, 1985; May 1985

The University of Minnesota, the Minnesota Geological Survey, and the U.S. Geological Survey are studying the feasibility of storing water at a temperature of 150 degrees Celsius in the Franconia-Ironton-Galesville aquifer. The Aquifer Thermal-Energy Storage project has a doublet-well design with a well spacing of approximately 250 meters. One well will be used for cool-water supply, and, the other, for hot-water injection. The U.S. Geological Survey is constructing a model of ground-water flow and thermal-energy transport to aid in determining the efficiency of the Aquifer Thermal Energy Storage system. A preliminary model of radial flow and thermal-energy transport was constructed, based on hydraulic and thermal properties of the Franconia-Ironton-Galesville aquifer determined in previous studies. The model was used to investigate the sensitivity of model results to various hydraulic and thermal properties and to study the potential for buoyancy flow within the aquifer and the effect of various cyclic injection-withdrawal schemes on the relative thermal efficiency of the aquifer. Sensitivity analysis was performed assuming 8 days of injection of 150-degree-Celsius water at 18.9 liters per second, 8 days of storage, and 8 days of withdrawal of hot water at 18.9 liters per second. The analysis indicates that, for practical ranges of hydraulic and thermal properties, rock-heat capacity is the least important property and thermal dispersivity is the most important property used to compute temperature and aquifer thermal efficiency. The amount of buoyancy flow was examined for several values of hydraulic conductivity and ratios of horizontal to vertical hydraulic conductivities. For the assumed base values of hydraulic and thermal properties, buoyancy flow was negligible. The greatest simulated buoyancy flow resulted from simulations in which horizontal hydraulic conductivity was increased to 10 times the base value, and the vertical hydraulic conductivity was set equal to the horizontal hydraulic conductivity. The effects of various injection-withdrawal rates and durations on computed values of aquifer relative thermal efficiency and final well-bore temperature were studied for five 1-year hypothetical test cycles of injection and withdrawal. The least efficient scheme was 8 months injection of 150-degree-Celsius water and 4 months of withdrawal of hot water at 18.9 liters per second. The most efficient scheme was obtained with 6 months of injection of 150-degree-Celsius water at 18.9 liters per second and 6 months of withdrawal of hot water at 37.8 liters per second. The hypothetical simulations indicate that the subsequent calibrated model of the doublet-well system will be a valuable tool in determining the most efficient system operation.

Water Supply Paper↗

Selected papers in the hydrologic sciences, 1986

West Point Reservoir is a multiple-purpose project on the Chattahoochee River about 112 river kilometers downstream from Atlanta on the Alabama-Georgia border. Urbanization has placed large demands on the Chattahoochee River, and water quality below Atlanta was degraded even before impoundment. Water-quality, bottom-sediment, and fish-tissue samples were collected from the reservoir to determine whether water-quality problems have occurred subsequent to impoundment. Severe hypolimnetic oxygen deficiency occurred in the reservoir following thermal stratification in the spring of 1978 and 1979. During stratified periods, concentrations of dissolved iron and manganese in the hypolimnion at the dam pool ranged from 0 to 7,700 and 30 to 2,000 micrograms per liter, respectively. During thermally stratified periods, phytoplankton standing crops in the upper lentic section of the reservoir ranged from 39,000 to 670,000 cells per milliliter. A maximum algal growth potential value (U.S. Geological Survey method) of 48.0 milligrams per liter was obtained at the uppermost data-collection station. The primary growth-limiting nutrients were nitrogen in the Iotic section and phosphorus in the lentic section. The highest measured concentrations of volatile solids and total iron, manganese, phosphorus, and organic carbon in sediments occurred in the lentic section of the reservoir, where bottom sediments consist mainly of silt and clay. Polychlorinated biphenyls and chlordane concentrations in the bottom sediments were as high as 740 and 210 micrograms per kilogram, respectively. Concentrations of polychlorinated biphenyls and chlordane in fish tissue ranged from 19 to 3,800 and 6.0 to 280 micrograms per kilogram, respectively.

Water Supply Paper↗

Selected papers in the hydrologic sciences, 1986

Water-quality data from long-term (24 years), fixed- station monitoring at the Cape Fear River at Lock 1 near Kelly, N.C., and various measures of basin development are correlated. Subbasin population, number of acres of cropland in the subbasin, number of people employed in manufacturing, and tons of fertilizer applied in the basin are considered as measures of basinwide development activity. Linear correlations show statistically significant posi- tive relations between both population and manufacturing activity and most of the dissolved constituents considered. Negative correlations were found between the acres of harvested cropland and most of the water-quality measures. The amount of fertilizer sold in the subbasin was not statistically related to the water-quality measures considered in this report. The statistical analysis was limited to several commonly used measures of water quality including specific conductance, pH, dissolved solids, several major dissolved ions, and a few nutrients. The major dissolved ions included in the analysis were calcium, sodium, potassium, magnesium, chloride, sulfate, silica, bicarbonate, and fluoride. The nutrients included were dissolved nitrite plus nitrate nitrogen, dissolved ammonia nitrogen, total nitrogen, dissolved phosphates, and total phosphorus. For the chemicals evaluated, manufacturing and population sources are more closely associated with water quality in the Cape Fear River at Lock 1 than are agricultural variables.

Water Supply Paper↗

Satellite telemetry of marine megavertebrates: The coming of age of an experimental science

Wildlife telemetry research has expanded greatly in the last 2 decades, with the application of satellite tracking and archival logging technologies to study the ecology and conservation of marine mammals, birds, fishes, and turtles. Widespread and expanding use of satellite tracking to study movements and habitats of marine megavertebrates warrants a review of progress to date and a discussion of challenges facing this rapidly evolving research field. To this end, we reviewed the satellite telemetry literature of air-breathing marine taxa (i.e. birds, mammals, turtles) over the 20 yr time period from 1987 to 2006. This review yielded 92 studies with a wide taxonomic representation: 47 seabirds, 23 sea turtles, and 22 marine mammals. Here we critically evaluate these articles to assess progress in satellite tracking of marine megavertebrates in terms of (1) objectives and approach, (2) experimental design, and (3) reporting of results. The overall trends revealed increases in the duration and scope of tracking studies, yet improvements on experimental design and reporting are needed to facilitate comparisons across studies and species. While inherent ecological differences influence the focus and methods of taxon-specific studies, this review highlights specific areas in need of improvement and provides general suggestions for future tracking studies of marine megavertebrates.

Endangered Species Research↗

One hundred pressing questions on the future of global fish migration science, conservation, and policy

Migration is a widespread but highly diverse component of many animal life histories. Fish migrate throughout the world's oceans, within lakes and rivers, and between the two realms, transporting matter, energy, and other species (e.g., microbes) across boundaries. Migration is therefore a process responsible for myriad ecosystem services. Many human populations depend on the presence of predictable migrations of fish for their subsistence and livelihoods. Although much research has focused on fish migration, many questions remain in our rapidly changing world. We assembled a diverse team of fundamental and applied scientists who study fish migrations in marine and freshwater environments to identify pressing unanswered questions. Our exercise revealed questions within themes related to understanding the migrating individual's internal state, navigational mechanisms, locomotor capabilities, external drivers of migration, the threats confronting migratory fish including climate change, and the role of migration. In addition, we identified key requirements for aquatic animal management, restoration, policy, and governance. Lessons revealed included the difficulties in generalizing among species and populations, and in understanding the levels of connectivity facilitated by migrating fishes. We conclude by identifying priority research needed for assuring a sustainable future for migratory fishes.

Frontiers in Ecology and Evolution↗

Using decision science for monitoring threatened western snowy plovers to inform recovery

Western Snowy Plovers ( Charadrius nivosus nivosus ) are federally listed under the US Endangered Species Act as Threatened. They occur along the US Pacific coastline and are threatened by habitat loss and destruction and excessive levels of predation and human disturbance. Populations have been monitored since the 1970s for distribution, reproduction, and survival. Since the species was federally listed in 1993 and a recovery plan was approved under the US Fish and Wildlife Service in 2007, recovery actions have resulted in growing populations with increased presence at breeding and wintering sites throughout their Pacific Coast range. This success has created logistical challenges related to monitoring a recovering species and a need for identifying and instituting the best monitoring approach given recovery goals, budgets, and the likelihood of monitoring success. We devised and implemented a structured decision analysis to evaluate nine alternative monitoring strategies. The analysis included inviting plover biologists involved in monitoring to score each strategy according to a suite of performance measures. Using multi-attribute utility theory, we combined scores across the performance measures for each monitoring strategy, and applied weighted utility values to show the implications of tradeoffs and find optimal decisions. We evaluated four scenarios for weighting the monitoring objectives and how risk attitude affects optimal decisions. This resulted in identifying six strategies that best meet recovery needs and were Pareto optimal for cost-effective monitoring. Results were presented to the US Fish and Wildlife Service, responsible for monitoring as well as for consideration to ensure consistent monitoring methods across the species’ range. Our use of structured decision-making can be applied to cases of other species once imperiled but now on the road to recovery.

California, Oregon, Washington↗

Statistical facilitation in environmental science: Integrating results from complementary statistical analyses can improve ecological interpretations

Professionals working in biological conservation seek to understand, manage, and restore populations of native organisms using many techniques. A common approach for this discipline is using long-term data collections to inform decision making. However, several quantitative issues complicate statistical analysis of monitoring datasets and can reduce the utility of results for conservation decision making. Integrating results from multiple analyses applied to the same dataset (i.e., approaching the same biological problem using different techniques) is one way to address concerns related to field data that violate statistical assumptions. This process allows data analysts, researchers, and managers to assemble insights based on the weight of evidence. Here we tested whether three different statistical techniques [(1) multiple logistic regression on original data, (2) multiple logistic regression on standardized data (i.e., mean of 0 and standard deviation of 1), and (3) random forest analysis] identified a similar hierarchy for selecting natural and anthropogenic habitat regressors. Our examination of how environmental variables affected Plains Minnow ( Hybognathus placitus ), a state-threatened fish, is relevant to other taxa and locations. We gained useful information from redundancies (i.e., agreements across analyses). New directions also emerged by addressing ambiguities (i.e., disagreements among results across analyses). When multiple analyses were integrated into one ecological story, a clearer interpretation emerged. Viewing different statistical tests as facilitators that provide mutual advantages can advance the understanding and application of statistical analyses applied to non-experimental field datasets.

Kansas↗

Mapping presence and predicting phenological status of invasive buffelgrass in southern Arizona using MODIS, climate and citizen science observation data

The increasing spread and abundance of an invasive perennial grass, buffelgrass ( Pennisetum ciliare ), represents a critical threat to the native vegetation communities of the Sonoran desert in southern Arizona, USA, where buffelgrass eradication is a high priority for resource managers. Herbicidal treatment of buffelgrass is most effective when the vegetation is actively growing, but the remoteness of infestations and the erratic timing and length of the species’ growth periods confound effective treatment. The goal of our research is to promote buffelgrass management by using remote sensing data to detect where the invasive plants are located and when they are photosynthetically active. We integrated citizen scientist observations of buffelgrass phenology in the Tucson, Arizona area with PRISM precipitation data, eight-day composites of 250-m Moderate-resolution Imaging Spectroradiometer (MODIS) satellite imagery, and aerially-mapped polygons of buffelgrass presence to understand dynamics and relationships between precipitation and the timing and amount of buffelgrass greenness from 2011 to 2013. Our results show that buffelgrass responds quickly to antecedent rainfall: in pixels containing buffelgrass, higher correlations (R 2 > 0.5) typically occur after two cumulative eight-day periods of rain, whereas in pixels dominated by native vegetation, four prior 8-day periods are required to reach that threshold. Using the new suite of phenometrics introduced here—Climate Landscape Response metrics—we accurately predicted the location of 49% to 55% of buffelgrass patches in Saguaro National Park. These metrics and the suggested guidelines for their use can be employed by resource managers to treat buffelgrass during optimal time periods.

Arizona↗