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At least 1,225 records · Page 68Linked to original sources
USGS2002

Near field receiving water monitoring of benthic community near the Palo Alto Water Quality Control Plant in south San Francisco Bay: February 1974 through December 2000

Analyses of the benthic community structure over a 26-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinal clam Macoma balthica from the same area. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that could be indicative of a more stable community that is subjected to less stress. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals. Heteromastus filiformis, a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying their eggs on or in the sediment has shown a concurrent increase in dominance. These changes in species dominance reflect a change in the community from one dominated by surface dwelling, brooding species to one with species with varying life history characteristics. Analysis of the reproductive activity of Macoma balthica shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissue of this organism. Reproductive activity is presently stable with almost all animals reproducing during the two reproductive seasons (spring and fall) of most years.

California↗
USGS2003

Near-field receiving water monitoring of a benthic community near the Palo Alto Water Quality Control Plant in South San Francisco Bay: February 1974 through December 2002

Analyses of the benthic community structure over a 28-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinal clam Macoma balthica from the same area. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that could be indicative of a more stable community that is subjected to less stress. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals. Heteromastus filiformis, a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying their eggs on or in the sediment has shown a concurrent increase in dominance. These changes in species dominance reflect a change in the community from one dominated by surface dwelling, brooding species to one with species with varying life history characteristics. Analysis of the reproductive activity of Macoma balthica shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissue of this organism. Reproductive activity is presently stable with almost all animals reproducing during the two reproductive seasons (spring and fall) of most years. These findings are consistent with findings previously reported for the 1974 through 2000 period.

California↗
USGS2004

Near-field receiving water monitoring of a benthic community near the Palo Alto Water Quality Control Plant in south San Francisco Bay: February 1974 through December 2003

Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 29-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinal clam Macoma balthica from the same area. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that could be indicative of a more stable community that is subjected to less stress. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes have shown a continual decline in dominance coincident with the decline in metals. Heteromastus filiformis, a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying their eggs on or in the sediment has shown a concurrent increase in dominance. These changes in species dominance reflect a change in the community from one dominated by surface dwelling, brooding species to one with species with varying life history characteristics. Analysis of the reproductive activity of Macoma balthica shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissue of this organism. Reproductive activity is presently stable with almost all animals reproducing during the two reproductive seasons (spring and fall) of most years. These findings are consistent with findings previously reported for the 1974 through 2002 period.

California↗
USGS2025

Biodiversity surveys of Wake Atoll—Featuring field guides for plants, arthropods, and herpetofauna

Introduction The U.S. Air Force (USAF) issued funds to the U.S. Geological Survey (USGS) to update the biosecurity plan, create a current (2019) flora and fauna species identification index, and do container evaluations for the presence of potential invasives. The current (2019) biosecurity protocols used for prevention were evaluated, and new biodiversity surveys were completed for terrestrial vegetation and arthropods and included the first formal reptile surveys. Results from field efforts add to existing knowledge and may identify new species arrivals to Wake. One goal of this project was to update and compile established species information for the atoll and create species identification guides for the three taxonomic groups surveyed. We made these flora and fauna species identification guides by compiling results of the recent (2019) and historical surveys. The guides can be used as resident desktop references, as a baseline for assessing future natural resource surveys, and to assist with guiding management actions. We refer herein to biosecurity and integrated pest management plan materials, which we created simultaneously to inform current (2019) biosecurity and to identify some of the top invasive species at Wake. This study was done in cooperation with the USAF, and surveys were performed for the 611th Civil Engineer Squadron Natural Resources Program, ACES PROJECT #YGFZ170002 under agreement number F2MUAA7116GW02 between the USAF and the USGS Western Ecological Research Center.

Open-File Report↗
USGS1965

Plant microfossils of the Hazard No. 7 coal, Perry County, Kentucky

The cooperative mapping program between the Kentucky Geological Survey and the U. S. Geological Survey has yielded a number of interesting and valuable by-products. As a part of the stratigraphic studies involving Carboniferous coal fields, R. M. Kosanke has been involved in a detailed analysis of spore floras from various coal horizons. This study is aimed toward a correlation within the eastern coal field and, eventually, toward more accurate correlations with the western Kentucky coal fields.

Kentucky↗
USGS1966

Plant microfossils from the Fort Union Formation

As a part of continuing studies to provide palynological data from critical sequences for comparative biostratigraphic studies, the microfossils found in two Paleocene samples have been examined and photographed.

Open-File Report↗