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At least 55 records · Page 3Linked to original sources

Spatiotemporal variability of algal biomass and nitrate in Owasco and Seneca Lakes in the Finger Lakes Region, New York, in 2019

Cyanobacterial harmful algal blooms (CyanoHABs) have become increasingly common, threatening the security of water resources globally. The U.S. Geological Survey conducted high-resolution nearshore mapping surveys using boat-mounted multiparameter sondes and nitrate sensors during the summer and fall of 2019 on Owasco Lake and Seneca Lake, two lakes with documented CyanoHABs in the Finger Lakes region of New York State. Discrete sensor measurements and water-quality samples were collected at fixed points along survey routes and continuous data were generated at open-water monitoring platforms. This investigation examined whether water-quality information from nearshore surveys was representative of open-water conditions and if nearshore surveys could be used to identify areas with localized nearshore CyanoHABs and potential sources of nutrients not captured by tributary sampling. In addition to comparisons across methods, nearshore concentrations of nitrate and chlorophyll were evaluated relative to tributary outlets, cyanobacterial abundance and biovolume at discrete locations, and the locations of near-surface CyanoHABs that were designated as “confirmed with high toxins” by the New York State Department of Environmental Conservation. Nitrate and chlorophyll concentrations were comparable across methods for each lake, although concentration ranges were typically higher for nearshore mapping datasets than for nearshore discrete datasets. Nearshore surveys indicated areas of nitrate enrichment that varied temporally in both lakes. Orthophosphate was not routinely detected. Across methods, median chlorophyll concentrations were higher for the summer survey than for the fall survey in Owasco Lake. Nearshore chlorophyll concentrations varied more temporally in Owasco Lake than in Seneca Lake. Phytoplankton and cyanobacterial abundance and biovolume were about five times higher in Owasco Lake than in Seneca Lake. Cyanobacteria dominated the phytoplankton community in most samples, and Microcystis comprised the bulk of the cyanobacterial biovolume. The most abundant potential cyanotoxin-producing (specifically microcystins) genera were Microcystis , Synechococcus , Aphanocapsa , and Pseudanabaena . The cyanobacterial community composition was comparable between open-water monitoring platforms and nearshore samples. Microcystins were detected in seven survey samples from Owasco Lake, in one survey sample from Seneca Lake, and in one sample each from the open-water monitoring platforms on Owasco and Seneca Lakes that were collected about 7 days before the fall surveys. Microcystin detections were not consistently associated with high cyanobacterial cell counts or cyanotoxin-producing genera. Results from nearshore surveys were comparable to open-water monitoring platforms and discrete nearshore observations in the absence of nearshore or open-water CyanoHABs in these systems during the study. Patterns of nearshore concentrations of nitrate and chlorophyll from nearshore surveys may aid in the identification of areas with localized nitrate loading and shifts in phytoplankton abundance and community composition.

New York↗

The US Geological Survey's National Mapping Division programs, products, and services that can support wetlands mapping

The US Geological Survey (USGS) programs can play an important role in support of President Bush's policy of no net loss of wetlands. A principal goal of USGS is to provide cartographic information that contributes to the wise management of the Nation's natural resources. This information consists of maps, cartographic data bases (graphic and digital), remotely sensed imagery, and information services. These products are used by Federal, State, and local governments, the private sector, and individual citizens in making decisions on the existence and use of land and water resources. I discuss the programs, products, and information services of the National Mapping Division, the tools available to determine where wetlands exist, and the capability of periodic measurement of wetlands to help in assessing compliance with the concept of no net loss of wetlands. -from Author

Biological Report - US Fish & Wildlife Service↗

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1976

The water table in the surficial aquifer (sand) and the potentiometric surface of the Floridan aquifer (limestone) in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared each May and September to coincide with seasonal low and high ground-water levels. The mapped area contains nine producing well fields which supplied 92.8 million gallons on May 12, 1976 to municipalities along the Gulf Coast. This pumpage came from the Floridan aquifer, the major aquifer in the State of Florida. The effect of well-field withdrawals is shown on the maps as cones of depression in both the potentiometric and water-table surfaces. The May 1976 maps indicate that water levels have declined below sea level in some areas. The decline results from reduced recharge during the dry spring combined with an increase in pumpage for lawn irrigation.

Open-File Report↗

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, September 1977

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200 square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared on the basis of water levels measured in wells each May to coincide with seasonal low levels; and in September, when levels are high. The mapped area for this report contains nine producing wells fields which supplied 76.2 million gallons on September 21, 1977, to municipalities in the Tampa Bay area. The effect of localized withdrawal of groundwater from the Floridan aquifer is shown on the maps as cones of depression in both the potentiometric surface and water table. In September, water levels in observation wells in the Floridan aquifer were above those measured in May. These increases ranged from about 1 foot at the Eldridge-Wilde well field to about 25 feet at the Sun City well field. (Woodard-USGS)

Open-File Report↗

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1978

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 11 well fields which supplied 144.0 million gallons to municipalities on May 16, 1978. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were generally lower in May 1978 than in September 1977 because of seasonal rainfall. The maximum decrease determined was more than 17 feet at Sun City well field. Water levels in May 1978 were generally higher than in May 1977 because of heavy rainfall in early May. However, water levels in well fields with significant increases in pumpage were lower.

Florida↗

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1979

The water table is the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 16 well fields which supplied 128 million gallons to municipalities on May 15, 1979. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. Water levels were significantly higher in May 1979 than in May 1978. Heavy rains on May 7 and 8th deluged the well-field areas with 2 to 18 inches of rain. The maximum increase in water levels from May 1978 to May 1979 was more than 8 feet at the Eldridge-Wilde well field. (USGS)

Open-File Report↗

Ground-water levels in selected well fields and in west-central Florida, May 1980

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well-field areas that supplied 155 million gallons to municipalities on May 12, 1980. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were lower in May 1980 than in September 1979 and a little higher than the average May levels. Change of water levels ranged from a decrease of 12 feet at Verna well field to an increase of 7 feet at Eldridge-Wilde well field. (USGS)

Open-File Report↗

Ground-water levels in selected well fields and in west-central Florida, September 1979

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 16 well fields which supplied 123.7 million gallons to municipalities on September 18, 1979. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were generally higher in September 1979 than in May 1979 and higher than the average September levels. Change of water levels ranged from an increase of 15 feet at Cosme well field to a decrease of 9 feet at Verna well field.

Florida↗

Ground-water levels in selected well fields and in west-central Florida, September 1980

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 141.8 million gallons to municipalities on September 18, 1980. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Potentiometric levels in the Floridan aquifer were higher in September 1980 than in May 1980 and generally lower than in September 1979. Annual change of water levels ranged from a decrease of 6 feet at Morris Bridge well field to an increase of 2 feet at Eldridge-Wilde well field. (USGS)

Open-File Report↗

Ground-water levels in selected well fields and in west-central Florida, September 1981

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 140.3 million gallons to municipalities on September 21, 1981. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal on ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. In September 1981, ground-water levels were significantly higher than those of May 1981 and were unchanged or within a few feet of those in September 1980. Seasonal recharge from summer rains and reduced pumpage are factors in the water-level recovery from record and near record low levels of May 1981. (USGS)

Open-File Report↗

Ground-water levels in selected well fields and in west-central Florida, May 1982

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,700-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with the seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 181.1 million gallons to municipalities on May 10, 1982. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal on ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. In May 1982, ground-water levels were lower than those of September 1981. Seasonal recharge from above-average rainfall and reduced pumpage aided in the water-level recovery from record to near record levels of May 1981. (USGS)

Open-File Report↗

Improved Automated Identification and Mapping of Iron Sulfate Minerals, Other Mineral Groups, and Vegetation using Landsat 8 Operational Land Imager Data, San Juan Mountains, Colorado, and Four Corners Region

Multispectral remote sensing data acquired by the Landsat 8 Operational Land Imager (OLI) sensor were analyzed using a new, automated technique to generate a map of exposed mineral and vegetation groups in the western San Juan Mountains, Colo., and the Four Corners Region of the United States. Band ratio results were combined into displayed mineral and vegetation groups using Boolean algebra. New analysis logic has been implemented to exploit the coastal aerosol band in Landsat 8 OLI data and identify concentrations of iron sulfate minerals. These may indicate the presence of near-surface pyrite, which can be a potential nonpoint source of acid rock drainage. Zoned occurrences of iron sulfate minerals in areas surrounding and down gradient of known sources of pyrite have been mapped using this technique. They show high correlation with occurrences of jarosite-bearing mineral assemblages, as mapped using airborne imaging spectrometer data and supporting field verification surveys. Mapping the occurrence of iron sulfate minerals produced by the weathering and oxidation of pyrite in exposed hydrothermally altered rocks can also provide an important indicator of the genetic environment of alteration and the associated mineral deposit type. The automated analysis methodology is being employed to rapidly and cost-effectively generate maps of large regions of the United States in support of U.S. Geological Survey mineral resource and mineral-environmental assessments. This map, which includes the ERDAS IMAGINE thematic raster format in the data release, has been attributed by pixel value with mineral and vegetation group classification data, which can be queried in most image processing and GIS software packages.

Colorado, Utah↗

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, September 1976

The water table in the surficial aquifer and the potentiometric surface of the Florida aquifer in a 1200 square-mile area in west-central Florida are mapped semiannually by the U. S. Geological Survey. Maps are prepared on the basis of water levels measured in wells each May to coincide with seasonal low levels, and in September, when levels are high. The mapped area contains nine producing well fields which supplied 67.2 million gallons on September 8, 1976, to municipalities along the Gulf Coast. The water is from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as cones of depression in both the potentiometric and water-table surfaces. The September 1976 maps show the seasonal rise in water levels from the low levels of the previous May.

Open-File Report↗

Mapping wetlands on beaver flowages with 35-mm photography

Beaver flowages and associated wetlands on the Chippewa National Forest, north-central Minnesota, were photographed from the ground and from the open side window of a small high-wing monoplane. The 35-mm High Speed Ektachrome transparencies obtained were used to map the cover-type associations visible on the aerial photographs. Nearly vertical aerial photos were rectified by projecting the slides onto a base map consisting ofcontrol points located by plane-table survey. Maps were prepared by tracing the recognizable stands of vegetation in the rectified projection at the desired map scale. Final map scales ranging from 1:260 to 1:571 permitted identification and mapping of 26 cover-type associations on 10 study flowages in 1971. This cover-mapping technique was economical and substituted for detailed ground surveys. Comparative data from 10 flowages were collected serially throughout the entire open-water season. Although developed for analysis of waterfowl habitat, the technique has application to other areas of wildlife management and ecological investigation.

Canadian Field-Naturalist↗