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At least 163 records · Page 9Linked to original sources
USGS1963

Selected hydrologic data, Pavant Valley, Millard County, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1959-62 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of ground-water conditions in Pavant Valley in Millard County, Utah. The interpretive material will be published in a companion report by Reed W. Mower. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate l and examine the records of nearby wells as shown in the tables. From tables l and 3 he can note the type of material that yields water to wells in the vicinity; from table 1 he can note (1) the depth and diameter of wells in the vicinity and the yield of some of those wells, and (2) the depth to water or the feet of water pressure in the vicinity; from table 2 he can note the historic fluctuations and trends of water levels in the vicinity; from table 4 he can note the chemical quality of the water from wells in the vicinity; and from table l he can find the use made of the well water. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the State Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1964

Ground-water data, Sevier Desert, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources, and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1935-64 by the U.S. Geological survey in cooperation with the Utah State Engineer as part of the investigation of ground-water conditions in the Sevier Desert, in Juab and Millard Counties, Utah. The interpretive material will be published in a companion report by R. W. Mower and R. D. Feltis. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown in the tables and figures. From table 1 he can note such things as depth, diameter, water level, yield, use of water, temperature of water, and depth of perforations. By comparing the depth of perforations with the drillers' logs in table 3 he can note the type of material that yields water to the wells. Table 2 and figure 2 show the historic fluctuations and trends of water levels in the vicinity. From table 4 he can note the chemical quality of the water from wells in the vicinity. Table 5 shows the amount of water discharged during 1951-63 from the pumped irrigation, public supply, and industrial wells. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the state Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1963

Selected hydrologic data, Jordan Valley, Salt Lake County, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1956-59 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of Ground-water conditions in the Jordan Valley, Utah. The interpretive material Will be published in a companion report by T. lendell Marine and Don Price. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site in plate 1 and examine the records of nearby wells as shown in the tables. From table 2 he can note the type of material that yields water to wells in the vicinity; from table l he can note (1) the depth and diameter of wells in the vicinity and the yield of some of those wells, and (2) the depth to water or the feet of water pressure in the vicinity; from table 1 and plate 1 he can note the location of springs; from tables 3 and l, he can note the chemical quality of the water from wells and springs and from surface sources in the vicinity; and from table l he can find the use made of the well and spring water. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the State Engineer. If the State Engineer believes that unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1964

Selected hydrologic data, upper Sevier River basin, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources, and (2) to supplement an interpretive report that will be published later. Records were collected during 1961-63 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of ground-water conditions in the upper Sevier River basin, in parts of Garfield, Iron, Kane, Piute, and Sevier Counties, Utah. The interpretive material will be published in a companion report by Carl H. Carpenter, Gerald B. Robinson, Jr., and Louis J. Bjorklund. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells and springs as shown in the tables. From table 1 he can find information on wells, including depth, diameter, water level, yield, drawdown, use of water, temperature of water, and depth of perforations. Table 2 gives information on springs such as yield, use of water, temperature, and improvements. From tables 1 and 2 he can note the type of material that yields water in the vicinity. Table 3 shows the historic fluctuations and trends of water levels. Table 4 shows the type of material penetrated by wells. From table 5 he can note the chemical quality of water from wells and springs, and from table 6, the chemical quality of surface water. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the State Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1961

Records and water-level measurements of selected wells and chemical analysis of ground water, East Shore area, Davis, Weber, and Box Elder Counties

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1935-61 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of the ground-water resources of the East Shore area in Davis, Weber, and southern Box Elder Counties, Utah. During the period 1952-61 additional records were collected by the U.S. Bureau of Reclamation. The interpretive material will be published cooperatively by the U.S. Geological Survey and the Utah State Engineer as a report entitled "Groundwater conditions in the East Shore area, Utah, 1953-61," by Ralph E. Smith. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown on the tables and figures. From table 1 he can note (1) the depth and diameter of wells in the vicinity and the yield of some of those wells, and (2) the depth to water or the feet of water pressure in wells in the vicinity; from table 2 and figure 2 he may note the historic fluctuations and trends of water levels in the vicinity; and from tables 3 and l he may note the chemical quality of the water from wells in the vicinity and the use made of this water. If the reader decides from his examination that conditions are favorable, he may place an application to drill a well with the State Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1962

Records of selected wells and springs, selected drillers' logs of wells, and chemical analyses of ground and surface waters, northern Utah Valley, Utah County, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1956-59 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of the ground-water resources of northern Utah Walley in Utah County, Utah. Some earlier data and other information in the tables are from published reports on the ground-water resources of northern Utah Walley. The interpretive material will be published cooperatively by the U.S. Geological Survey and the Utah State Engineer in a companion report by Seymour Subitzky. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown on the tables. From tables 1, 2, and h he can note the type of material that yields water to wells in the vicinity; from table 2 he can note (1) the depth and diameter of wells in the vicinity and the yield of some of those wells, and (2) the depth to water or the feet of water pressure in the vicinity; from table 3 and plate 1 he may note the location of springs and the conditions related to the occurrence of these springs; and from tables 5 and 6 he may note the chemical quality of the water from wells and from some surface sources, and the uses of these waters. If the reader decides from his examination that conditions are favorable, he may place an application to drill a well with the State Engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1963

Ground-water data, central Sevier Valley, parts of Sanpete, Sevier, and Piute Counties, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1956-60 by the U.S. Geological Survey in cooperation with the Utah State Engineer as a part of the investigation of ground-water conditions in the central Sevier Valley in parts of Sanpete, Sevier, and Piute Counties, Utah. The interpretive material will be published in a companion report by Richard A. Young and Carl H. Carpenter. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate l and examine the records of nearby wells as shown on the tables. From tables land 4 he can note the type of material that yields water to wells in the vicinity; from table 1 he can note (l) the depth and diameter of wells in the vicinity and the yield of some of those wells, and (2) the depth to water or the feet of water pressure in the vicinity; from table 3 he can note the historic fluctuations and trends of water levels in the vicinity; from table 2 and plate l he can note the location or springs and the conditions related to the occurrence of these springs; from table 5 he can note the chemical quality of the water from wells and springs in the vicinity; and from tables l and 2 he can find the use made of the well and spring water. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the state engineer. If the State Engineer believes unappropriated water is available, the application may be approved after minimum statutory requirements have been satisfied. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1953

Changes in chemical quality of the Arkansas River in Oklahoma and Arkansas (1946-52)

Systematic chemical quality-of-water investigations have been carried on in both Oklahoma and Arkansas by the Geological Survey in cooperation with State and Federal agencies during the past several years. Results of the Survey's quality-of-water investigations are usually published in the annual Water-Supply Papers. However, as the Geological Survey has made no sediment investigations in the Arkansas River Basin in Oklahoma and Arkansas, the published data do not include information on sediment concentrations or loads. This report attempts to summarize information collected to date in the Arkansas River Basin of the two States, and to show as clearly as possible from present information how the chemical quality of water in the Arkansas River changes downstream from the Oklahoma-Kansas State line to its confluence with the Mississippi River, and how it is affected by tributary inflows. Additional information is being collected and further studies are planned. Hence, the conclusions reached herein may be modified by more adequate information at a later date. The Arkansas River enters Oklahoma near Newkirk on the northern boundary just east of the 97th meridian, crosses the State in a general southeasterly direction flowing past Tulsa, enters Arkansas at its western boundary north of the 35th parallel near Fort Smith, still flowing in a general southeasterly direction past Little Rock near the center of the State, and empties into the Mississippi River east of Dumas. The Arkansas River is subject to many types of pollution downstream from the Oklahoma-Kansas State line, and its inferior quality along with an erratic flow pattern has caused it to be largely abandoned as a source of municipal and industrial water supply. At the present time, the Arkansas River is not directly used as a source of public supply in any part of the basin in either Oklahoma or Arkansas. In general, the river water increases in chemical concentration downstream from the Oklahoma-Kansas State line to Tulsa, due mainly to tributary inflow from the Salt Fork Arkansas River and the Cimarron River, both streams being sources of large amounts of both natural and artificial pollution. A decrease in chemical concentration is noted downstream from Tulsa due to tributary inflow from the Verdigris, Neosho, and Illinois rivers with an increase in chemical concentration then noted due to tributary inflow from the Canadian River which is largely artificial pollution. A steady decrease in concentration is then noted as the river progresses through Arkansas to the Mississippi River, as all major tributaries below the Canadian River have a dilution effect upon the chemical concentration of the Arkansas River water. Proposals for storage and regulating reservoirs on the Arkansas River in both Oklahoma and Arkansas have been made by the Corps of Engineers and others. Additional proposals are being considered in the present Arkansas-White-Red River Basin Inter-Agency Committee studies. If constructed, these reservoirs will provide an opportunity for control of flow and beneficial use of Arkansas River water, both at and downstream from these sites. Impoundment alone will greatly reduce the extremes in water quality, and by reasonable control of municipal and industrial wastes, the water would be comparable in quality to many existing basin municipal and industrial supplies. (available as photostat copy only)

Open-File Report↗
USGS1963

Ground-water data: Beaver, Escalante, Cedar City, and Parowan Valleys; parts of Washington, Iron, Beaver, and Millard Counties, Utah

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources, and (2) to supplement an interpretive report that will be published later. Records were collected during the period 1935-62 by the U.S. Geological Survey in cooperation with the Utah State Engineer as part of the investigation of ground-water conditions in the Beaver, Escalante, Cedar City, and Parowan Walleys. This report will include records collected subsequent to data published in earlier reports listed in the bibliography. The interpretive material will be published in a companion report by George W. Sandberg. This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown in the tables and figure 2. From table 1 he can note such things as diameter, depth, water level, yield, use of water, and depth to aquifers in wells in the vicinity, and from the well logs in table 3 he can note the type of material that yields water to the wells. Table 2 gives several years record of yields and pumping levels of irrigation wells, and in table 4 are the chemical analyses of water from wells and springs. Figure 2 shows the historic fluctuations and trends of water levels in the four valleys. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the State Engineer. During the past several years, however, the State Engineer has rejected new applications to appropriate water in major portions of Beaver Valley, Milford and Beryl-Enterprise districts in Escalante Valley, and Cedar City Valley. Anyone seeking to initiate a new ground-water right in any of these areas should obtain information from the State Engineer's Office in either Salt Lake City or Cedar City to determine the likelihood of approval of the required application. The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Utah↗
USGS1995

Planning long-term vegetation studies at landscape scales

Long-term ecological research is receiving more attention now than ever before. Two recent books, Long-term Studies in Ecology: Approaches and Alternatives , edited by Gene Likens (1989), and Long-term Ecological Research: An International Perspective , edited by Paul Risser (1991), prompt the question, “Why are these books so thin?” Except for data from paleoecological, retrospective studies (see below), there are exceptionally few long-term data sets in terrestrial ecology (Strayer et al. 1986; Tilman 1989; this volume). In a sample of 749 papers published in Ecology , Tilman (1989) found that only 1.7% of the studies lasted at least five field seasons. Only one chapter in each of the review books dealt specifically with expanding both the temporal and the spatial scales of ecological research (Berkowitz et al. 1989; Magnuson et al. 1991). Judging by the growing number of landscape-scale long-term studies, however, such as the Long-Term Ecological Research (LTER) Program (Callahan 1991), the U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP; Palmer et al. 1991), the U.S. Army’s Land Condition-Trend Analysis (LCTA) Program (Diersing et al. 1992), and various agencies’ global change research programs (CEES 1993), there is a growing interest to expand ecological research both temporally and spatially.

Book chapter↗
USGS1990

Textural development of clayey and quartzofeldspathic fault gouges relative to their sliding behavior

Many of the secondary fault structures developed during triaxial friction experiments have been generally correlated with the structures of natural fault zones. Therefore, any physical differences that can be found between laboratory samples that slide stably and those that show stick-slip motion may help to identify the cause of earthquakes. We have examined petrographically the run products of many triaxial friction experiments using clayey and quartzofeldspathic gouges, which comprise the principal types of natural fault gouge material. The examined samples were tested under a wide range of temperature, confining and fluid pressure, and velocity conditions. The clayey and quartzofeldspathic gouges show some textural differences, owing to their different mineral contents and grain sizes and shapes. In the clayey gouges, for example, a clay mineral fabric and kink band sets are commonly developed, whereas in the quartzofeldspathic gouges fracturing and crushing of the predominately quartz and feldspar grains are important processes. For both types of gouge, however, and whatever the pressure-temperature-velocity conditions of the experiments, the transition from stable sliding to stick-slip motion is correlated with: (i) a change from pervasive deformation of the gouge layer to localized slip in subsidiary shears; and (ii) an increase in the angle betweem the shears that crosscut the gouge layer (Riedel shears) and ones that form along the gouge-rock cylinder boundaries (boundary shears). This suggests that the localization of shear within a fault zone combined with relatively high Riedel-shear angles are somehow connected with earthquakes. Secondary fracture sets similar to Riedel shears have been identified at various scales in major strike-slip faults such as the San Andreas of the western United States (Wallace, 1973) and the Luhuo and Fuyun earthquake faults of China (Deng and Zhang, 1984; Deng et al. , 1986). The San Andreas also contains locked and creeping sections that correspond to the stick-slip and stably sliding experimental samples, respectively. We plan to study the physical structure of the San Andreas fault, to see if the experimentally observed differences related to sliding behavior can also be distinguished in the field.

Physics and Chemistry of the Earth↗
USGS2021

A renewed philosophy about supplemental sea lamprey controls

Invasive sea lamprey ( Petromyzon marinus ) populations in the Laurentian Great Lakes have been reduced by up to 90% through the use of selective pesticides (lampricides) and physical sea lamprey barriers that block spawning migrations. Nevertheless, other control methods are needed to achieve integrated pest management objectives, delay biological resistance, and address societal pressure to reduce pesticide use and restore lotic connectivity through dam removals. Despite decades of research and scientific advances, new control tools that focus on controlling adult and juvenile life stages have been rare because tactics have not been cost-effective alternatives to lampricides and sea lamprey barriers. Here, we propose a renewed philosophy highlighting that new control methods need not be true alternatives to lampricides and sea lamprey barriers (i.e., have similar effectiveness), but instead can be useful as supplemental controls integrated with current methods, especially in places where current methods are less effective due to environmental or societal conditions. Current case studies pairing multiple supplemental controls together on two Lake Huron tributaries, the Black Mallard and Cheboygan Rivers, have shown promise in reducing sea lamprey reproductive success, the scope of lampricide treatments, and ultimately the number of juvenile sea lampreys produced. Additional case studies are planned and will be evaluated within a decade-long adaptive assessment plan.

Journal of Great Lakes Research↗
USGS2022

Acquisition of Moon measurements by Earth orbiting sensors for lunar calibration

The reflected light from the Moon can be utilized as a reference for radiometric calibration by employing a model to generate reference values corresponding to the Moon observations made by instruments. Using a calibration target that is outside the atmosphere provides a distinct advantage for space-based instruments; however, the lunar irradiance sensed by satellite instruments naturally changes as the host spacecraft traverses its orbit. This article presents a study of the potential impact on lunar radiometric measurements due to their acquisition from an orbiting platform. A simulation of a Sun-synchronous orbit was coupled to the U.S. Geological Survey (USGS) lunar model to generate predicted irradiances for points along orbit passes through several lunations. These irradiance values exhibit variations tied to the spacecraft motion, arising primarily from changes in the Moon-sensor distance and the phase angle. The two effects are similar in overall magnitude, but their respective contributions depend on the time of month and the orbit. Relative changes in irradiance mostly fall within an envelope of ±0.006% per second, except at the smallest phase angles. These studies enable planning space-based Moon observations to minimize the change in the target irradiance, an important consideration for measurements acquired for radiometric characterization of the Moon.

IEEE Transactions on Geoscience and Remote Sensing↗
USGS2019

Hydrologic resilience from summertime fog and recharge: A case study for coho salmon recovery planning

Fog and low cloud cover (FLCC) and late summer recharge increase stream baseflow and decrease stream temperature during arid Mediterranean climate summers, which benefits salmon especially under climate warming conditions. The potential to discharge cool water to streams during the late summer (hydrologic capacity; HC) furnished by FLCC and recharge were mapped for the 299 subwatersheds ranked Core, Phase 1, or Phase 2 under the National Marine Fisheries Service Recovery Plan that prioritized restoration and threat abatement action for endangered Central California Coast Coho Salmon evolutionarily significant unit. Two spatially continuous gridded datasets were merged to compare HC: average hrs/day FLCC, a new dataset derived from a decade of hourly National Weather Satellite data, and annual average mm recharge from the USGS Basin Characterization Model. Two use‐case scenarios provide examples of incorporating FLCC‐driven HC indices into long‐term recovery planning. The first, a thermal analysis under future climate, projected 65% of the watershed area for 8–19 coho population units as thermally inhospitable under two global climate models and identified several units with high resilience (high HC under the range of projected warming conditions). The second use case investigated HC by subwatershed rank and coho population, and identified three population units with high HC in areas ranked Phase 1 and 2 and low HC in Core. Recovery planning for cold‐water fish species would benefit by including FLCC in vulnerability analyses.

California↗
USGS2014

An enhanced archive facilitating climate impacts analysis

We describe the expansion of a publicly available archive of downscaled climate and hydrology projections for the United States. Those studying or planning to adapt to future climate impacts demand downscaled climate model output for local or regional use. The archive we describe attempts to fulfill this need by providing data in several formats, selectable to meet user needs. Our archive has served as a resource for climate impacts modelers, water managers, educators, and others. Over 1,400 individuals have transferred more than 50 TB of data from the archive. In response to user demands, the archive has expanded from monthly downscaled data to include daily data to facilitate investigations of phenomena sensitive to daily to monthly temperature and precipitation, including extremes in these quantities. New developments include downscaled output from the new Coupled Model Intercomparison Project phase 5 (CMIP5) climate model simulations at both the monthly and daily time scales, as well as simulations of surface hydrologi- cal variables. The web interface allows the extraction of individual projections or ensemble statistics for user-defined regions, promoting the rapid assessment of model consensus and uncertainty for future projections of precipitation, temperature, and hydrology. The archive is accessible online (http://gdo-dcp.ucllnl.org/downscaled_ cmip_projections).

Bulletin of the American Meteorological Society↗
USGS2023

Comparing reintroduction strategies for the endangered San Francisco gartersnake (Thamnophis sirtalis tetrataenia) using demographic models

For endangered species persisting in a few populations, reintroductions to unoccupied habitat are a popular conservation action to increase viability in the long term. Identifying the reintroduction strategy that is most likely to result in viable founder and donor populations is essential to optimally use resources available for conservation. The San Francisco gartersnake ( Thamnophis sirtalis tetrataenia ) is an endangered sub-species that persists in a small number of populations in a highly urbanized region of California. Most of the extant populations of San Francisco gartersnakes have low adult abundance and effective population size, heightening the need for establishment of more populations for insurance against the risk of extinction. We used simulations from demographic models to project the probability of quasi-extinction for reintroduced populations of San Francisco gartersnakes based on the release of neonate, juvenile, adult, or mixed-age propagules. Our simulation results indicated that the release of head-started juveniles resulted in the greatest viability of reintroduced populations, and that releases would need to continue for at least 15 years to ensure a low probability of quasi-extinction. Releasing captive-bred juvenile snakes would also have less effect on the viability of the donor population, compared to strategies that require more adult snakes to be removed from the donor population for translocation. Our models focus on snake demography, but the genetic makeup of donor, captive, and reintroduced populations will also be a major concern for any proposed reintroduction plan. This study demonstrates how modeling can be used to inform reintroduction strategies for highly imperiled species.

PLoS ONE↗
USGS2006

Evaluation of eelgrass beds mapping using a high-resolution airborne multispectral scanner

Eelgrass ( Zostera marina ) can provide vital ecological functions in stabilizing sediments, influencing current dynamics, and contributing significant amounts of biomass to numerous food webs in coastal ecosystems. Mapping eelgrass beds is important for coastal water and nearshore estuarine monitoring, management, and planning. This study demonstrated the possible use of high spatial (approximately 5 m) and temporal (maximum low tide) resolution airborne multispectral scanner on mapping eelgrass beds in Northern Puget Sound, Washington. A combination of supervised and unsupervised classification approaches were performed on the multispectral scanner imagery. A normalized difference vegetation index (NDVI) derived from the red and near-infrared bands and ancillary spatial information, were used to extract and mask eelgrass beds and other submerged aquatic vegetation (SAV) in the study area. We evaluated the resulting thematic map (geocoded, classified image) against a conventional aerial photograph interpretation using 260 point locations randomly stratified over five defined classes from the thematic map. We achieved an overall accuracy of 92 percent with 0.92 Kappa Coefficient in the study area. This study demonstrates that the airborne multispectral scanner can be useful for mapping eelgrass beds in a local or regional scale, especially in regions for which optical remote sensing from space is constrained by climatic and tidal conditions.

Photogrammetric Engineering and Remote Sensing↗
USGS2003

Long-term and large-scale perspectives on the relationship between biodiversity and ecosystem functioning

In a growing body of literature from a variety of ecosystems is strong evidence that various components of biodiversity have significant impacts on ecosystem functioning. However, much of this evidence comes from short-term, small-scale experiments in which communities are synthesized from relatively small species pools and conditions are highly controlled. Extrapolation of the results of such experiments to longer time scales and larger spatial scales—those of whole ecosystems—is difficult because the experiments do not incorporate natural processes such as recruitment limitation and colonization of new species. We show how long-term study of planned and accidental changes in species richness and composition suggests that the effects of biodiversity on ecosystem functioning will vary over time and space. More important, we also highlight areas of uncertainty that need to be addressed through coordinated cross-scale and cross-site research.

BioScience↗