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Full-Text Articles in Fresh Water Studies

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett Nov 1998

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett

OES Faculty Publications

We investigated the ability of trace element and isotopic signatures in otoliths to record the nursery areas of juvenile (young-of-the-year) weakfish Cynoscion regalis from the east coast of the USA. Juvenile C. regalis were captured with otter trawls at multiple sites in Doboy Sound (Georgia), Pamlico Sound (North Carolina), Chesapeake Bay (Virginia), Delaware Bay (Delaware) and Peconic Bay (New York), from July to September 1996. One sagittal otolith from each specimen was assayed for Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca ratios using inductively coupled plasma mass spectrometry (ICP-MS), while delta 13 C and delta 18 O values from the other sagittal …


Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority Oct 1998

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997. It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …


Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith Aug 1998

Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith

AAES Research Reports and Research Bulletins

Agriculture is the largest use of soil and water resources in eastern Arkansas. This bulletin summarized the recent historical use of soil and water by agriculture and the impact of irrigation on yields of rice, soybeans and cotton. The experiments conducted in the field to quantitatively schedule irrigations of crops are summarized. The results show the close relationship between the irrigation of crops and the extraction of water from the Alluvial Aquifer. The implications of this relationaship for the future are discussed.


Inventory Of Sub-Catchments Within The Wilson Inlet Catchment, B Radys Jan 1998

Inventory Of Sub-Catchments Within The Wilson Inlet Catchment, B Radys

Resource management technical reports

The release of the "Salinity Action Plan for Western Australia' in December 996 highlighted the need for catchment scale planning and coordinated actions to reverse salinity trends.

A separate report has been produced for each major catchment area. Each report contains and inventory of all sub-catchments. with information on area, degradation risks and group activities with each catchment.


Non-Volatile Dissolved Organic Iodine In Marine Water, Xianhao Cheng Jan 1998

Non-Volatile Dissolved Organic Iodine In Marine Water, Xianhao Cheng

OES Theses and Dissertations

An analytical scheme for the determination of marine DOI has been established. The concentration of DOI is estimated as total iodine (TI) minus total inorganic iodine (TII). The concentration of total iodine is determined as [special characters omitted] after DOI has been oxidized to inorganic iodine quantitatively by intensive UV-irradiation and all the inorganic iodine in the samples had been converted to [special characters omitted] by the addition of NaClO.

Production of DOI in seawater can be via both non-phytoplankton and phytoplankton related processes. In the former, iodide is converted to DOI. In the latter, most likely, iodate is converted …


Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam Jan 1998

Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam

OES Faculty Publications

The elemental composition of fish otoliths may represent a permanent record of the environmental conditions an individual has experienced as trace elements, incorporated into the growing surface of the otolith, reflect the physical and chemical characteristics of the ambient water. We tested the utility of trace element signatures in otoliths as natural tags of the river of origin of juvenile American shad (Alosa sapidissima) collected from the Connecticut, Hudson and Delaware Rivers in August and October 1994. Four elements (K, Mn, Sr, and Ba) showed significant variability among sites within rivers in August, although only Mg showed a …


Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang Jul 1997

Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang

Biological Sciences Theses & Dissertations

The systematics of the amphipod genus Crangonyx of North America (north of Mexico) is revised, based on available collections (ca. 2240) and literature dealing with the genus. A grand total of 42 North America species of Crangonyx are recognized in the present study, 24 of them new to science. All species are described or redescribed and figured, utilizing external morphological features. Keys to both species groups and individual species are given. Phylogenetic trees are built using computer programs (PAUP, Hennig86, MacClade) based on 26 characters. Wagner parsimony produced 18 parsimonious trees and Fitch parsimony produced 45 trees. The consensus tree …


Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey Apr 1997

Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey

Publications (WR)

Las Vegas Wash, a natural wash east of the city of Las Vegas, Nevada, carries stormwater, groundwater drainage, and sewage effluent from three sewage treatment plants to Lake Mead. The Wash provides nearly the only surface water outlet for the entire 2,193 mi2 of Las Vegas Valley. A drainage area of 1,586 mi2 contributes directly to the Wash through surface flow which is channeled to Las Vegas Bay of Lake Mead, while drainage of the remaining 607 mi2 is presumably subsurface and may drain toward Las Vegas Wash.

In the 1930's and 1940's, sewage treatment plants were …


Bulletin 4333 - Furrow Sowing On Water Repellent Soils, Paul Blackwell, Grant Morrow Mar 1997

Bulletin 4333 - Furrow Sowing On Water Repellent Soils, Paul Blackwell, Grant Morrow

Bulletins 4000 -

This Bulletin discusses the benefits that furrow sowing brings to crop growth and production on water repellent sand, based on research and farm observations in Western Australian. By understanding the benefits and risks of several key processes, producers can better evaluate the potential role of furrow sowing in combating water repellency. This is true whether one is using direct drilling, no-till (narrow points or discs) or zero till (single, double or triple disc openers) methods.


The Influence Of The Wastewater Drainage From The Las Vegas Valley On The Limnology Of Boulder Basin, Lake Mead, Nevada-Arizona, James F. Labounty, Michael J. Horn, Bureau Of Reclamation Jan 1997

The Influence Of The Wastewater Drainage From The Las Vegas Valley On The Limnology Of Boulder Basin, Lake Mead, Nevada-Arizona, James F. Labounty, Michael J. Horn, Bureau Of Reclamation

Publications (WR)

Lake Mead, Colorado River, Arizona-Nevada, is one of the most heavily used reservoirs in the western United States, providing abundant recreational opportunities as well as downstream domestic and agricultural water for over 22 million users. Based on average nutrient levels and productivity, Lake Mead is classified as mildly mesotrophic. The interflow of the Colorado River dominates the limnology of much of the 106 km-long reservoir, and may still be identified at Hoover Dam under certain conditions. The lower basin of Lake Mead ending at Hoover Dam is known as Boulder Basin and is near the Las Vegas metropolitan area. Las …


Wetland Resources Of Eastern South Dakota, Rex R. Johnson, Kenneth F. Higgins Jan 1997

Wetland Resources Of Eastern South Dakota, Rex R. Johnson, Kenneth F. Higgins

Natural Resource Management Faculty Books

The mere mention of the word "wetland" in coffee shops and other gathering places on the prairies today brings out emotions and opinions that run the gamut from saving them all to draining them all. To some people, what we do with wetlands has been, and still is, a personal choice, a matter of exercising individual rights on private property. To others, wetlands are community resources that provide values that touch all of society. They contend that what is done to and about wetlands is a community decision regardless of ownership. Herein lies the controversy we have experienced over wetlands …


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo Jan 1997

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo

Watershed Sciences Faculty Publications

Physical characteristics of lakes are highly interrelated with biological characteristics. We measured and analyzed the physical characteristics of two side canyons in order to better understand differences in productivity between side canyons and the main channel and to provide general information on the characteristics of the lake.


Response Of Otolith Microchemistry To Environmental Variations Experienced By Larval And Juvenile Atlantic Croaker (Micropogonias Undulatus), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana Jan 1997

Response Of Otolith Microchemistry To Environmental Variations Experienced By Larval And Juvenile Atlantic Croaker (Micropogonias Undulatus), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana

OES Faculty Publications

Minor and trace elements incorporated into otoliths during growth may permanently record environmental conditions experienced by fishes. To determine the validity of this approach, we used laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) to assay sectioned otoliths from juvenile Atlantic croaker (Micropogonias undulatus) collected from each of three sites in the Neuse River, North Carolina, and the Elizabeth River, Virginia. Elemental concentrations at the center of the otoliths did not differ between locations, although both Mg : Ca and Ba : Ca were significantly higher at the edge of otoliths from the Neuse River than from the …


Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt Jan 1997

Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt

Biological Sciences Faculty Publications

In south Florida, Caribbean spiny lobsters (Panulirus argus) settle and spend their first few months in macroalgae or seagrass. After a few months, these ''algal-phase'' juveniles emerge from vegetation and, as ''postalgal-phase'' juveniles, seek refuge in crevices, often dwelling in groups. The importance of crevice shelters in determining the abundance of postalgal-phase juvenile spiny lobsters has been studied but we know little about the processes affecting lobster distribution and survival during their cryptic algal-dwelling phase. We found that postlarval supply varied independently of changes in the structure of macroalgal settlement habitat. For this reason, postlarval supply alone can not reliably …


Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission Nov 1996

Western Australian Salinity Action Plan, Agriculture Western Australia, Department Of Conservation And Land Management, Department Of Environmental Protection, Water And Rivers Commission

Natural resources published reports

Salinity is one of the State's most critical environmental problems, threatening major economic and social consequences. It is preventable and, in the long term, reversible. Complete elimination is not realistic, but we can dramatically reduce its impact.

Salinity is caused by replacing deep-rooted native plants with shallow-rooted crops and pastures. More rainfall passed below the root zone and accumulates as groundwater so that watertables rise. The groundwater mobilises natural salts in the soil as it rises and carries them towards the surface, eventually degrading land and streams.


Diversity Of Arkansas Water Resources Research, Kenneth F. Steele Oct 1996

Diversity Of Arkansas Water Resources Research, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

In order to understand, protect, and manage our water resources effectively knowledge is required from many diverse areas of science, engineering, economics, and sociology. These proceedings of the conference on the Diversity of Arkansas Water Resources Research reflect this need and demonstrate how researchers in the state are responding to water issues and problems in Arkansas. The papers in these proceedings are representative of the research in Arkansas, but are only a sample of the work being conducted by universities and government agencies in Arkansas. We are grateful that Arkansas has the expertise available to provide the information necessary to …


Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation Apr 1996

Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation

Publications (WR)

Field sampling was carried out between 0830 and 1500 beginning at the confluence of Las Vegas Wash and the Inner Las Vegas Bay. Ten (10) locations were sampled, each in a similar manner. Locations of sampling stations are in line from the Wash-Bay confluence to a point midway between Saddle and Black Islands. In addition, sampling was done at a location midway between Sentinel Island and the base of Fortification Hill, and at the buoy line in front of Hoover Dam. Sampling stations are labeled from LV01, at Wash-Bay confluence, to LV17 at Hoover Dam. A significant data collection point …


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell, Wayne A. Wurtsbaugh, Kirsten L. Gallo Jan 1996

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell, Wayne A. Wurtsbaugh, Kirsten L. Gallo

Watershed Sciences Faculty Publications

From 18-21 April 1996, students in a Utah State University class (Aquatic Ecology Laboratory; FW 560) measured limnological and fisheries characteristics in two side canyons (Halls Creek Bay and Moki Canyon) and the main channel of Lake Powell. Inclement weather precluded sampling of two other side canyons. Most of the sub-projects, directed by indiVIdual students, addressed the following two hypotheses: (1) productivity gradients existed from the inflows of the side canyons toward the main channel and; (2) productivity was higher in the side canyons than in the main channel of the lake. In most cases, parameters were measured at 3-5 …


Modeling The Vertical Distribution Of Oyster Larvae In Response To Environmental Conditions, Margaret M. Dekshenieks, Eileen E. Hofmann, John M. Klinck, Eric N. Powell Jan 1996

Modeling The Vertical Distribution Of Oyster Larvae In Response To Environmental Conditions, Margaret M. Dekshenieks, Eileen E. Hofmann, John M. Klinck, Eric N. Powell

CCPO Publications

A size-structured, time and vertically-dependent model was used to investigate the effects of water column structure on the distribution of larvae of the oyster Crassostrea virginica. Formulations used to model larval growth and behavior are based upon laboratory studies. Simulated vertical larval distributions obtained for conditions representative of a well-mixed, partially stratified and strongly stratified water column illustrate the effect that salinity and temperature gradients have on moderating larval swimming and hence on larvae vertical location. For well-mixed conditions, smaller larvae are dispersed throughout most of the water column. For strongly stratified conditions, the smaller-sized larvae cluster within the …


Toolibin Catchment Revegetation Manual, Avril Baxter Jan 1996

Toolibin Catchment Revegetation Manual, Avril Baxter

Natural resources published reports

In1983, heavy winter rains resulted in severe inundation and flooding of the lower parts of the Toolibin catchment. The damage to crops and pastures was immense and costly. Local farmers realised that they needed to work together to minimise the impact of heavy rainfall events on their farm productivity.

At the same time the Western Australian Department of Conservation and Land Management (CALM) was concerned about the quality of both ground and surface water in the catchment area for Toolibin Lake, the last remaining wooded freshwater lake in the southern wheatbelt. This mutual interest led to the formation of the …


Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range Jan 1996

Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range

Publications (WR)

The Nevada Basin and Range (NVBR) study unit of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is investigating the status of, trends in, and factors affecting water quality in the Las Vegas area. A principal objective of the investigation is to assess the effects of urbanization on the quality of area water resources. Las Vegas Wash is the surface-water outlet for the Las Vegas area. The wash transports stormwater runoff, shallow ground-water discharge, and tertiary-treated sewage effluent from the Las Vegas area to Las Vegas Bay of Lake Mead on the Colorado River. Most of the flow—about 96 …


Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman Sep 1995

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman

Publications (WR)

Algal bioassay tests were conducted with Selenastrum capricornutum and natural algae on inner Las Vegas Bay, Lake Mead, Nevada, from December 1992 through September 1993, to identify any nutrient limitation in an area of the reservoir that has experienced problems associated with severe nutrient enrichment. Three areas were sampled based on a gradient of water quality conditions that existed in Las Vegas Bay (LVB). Disodium ethylenedinitrilotetraacetate (EDTA) significantly stimulated algal growth compared to non-EDTA treatment. Algal bioassays indicated that phosphorus (P) was the primary limiting nutrient at all stations for most of the test dates. Chl a response with EDTA …


Brine Shrimp Ecology In The Great Salt Lake, Utah, Wayne A. Wurtsbaugh Jun 1995

Brine Shrimp Ecology In The Great Salt Lake, Utah, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Hypersaline lakes are noted for their simple communities which facilitate understanding ecological interactions (Williams et al. 1990; Wurtsbaugh 1992; Jellison and Melack 1988). Nevertheless, we still cannot easily predict how environmental changes will effect the population dynamics in these lakes, at least in part because even these simple ecosystems may be more complex than we .realize. Many hypersaline lakes are dominated by the brine shrimp Artemia spp. The production of brine shrimp is often very high because the terminal, saline lakes accumulate nutrients that make them rich, and because the short food chains in them (nutrients-->phytoplankton-->brine shrimp) minim …


The Effects Of Nutrient Loading On Plant And Algae Population: A Comparison Study Of East Gemini Lake And Lower Stumpf Lake, Nick Leonard Jan 1995

The Effects Of Nutrient Loading On Plant And Algae Population: A Comparison Study Of East Gemini Lake And Lower Stumpf Lake, Nick Leonard

Honors Theses, 1963-2015

Eutrophication of lakes has become an increasing problem for many bodies of water. By analyzing the nutrients available and the phytoplankton and macrophyte populations, evaluation and differentiation of East Gemini Lake and Stumpf Lake were made concerning their trophic state. This determination allowed for the further understanding of the effect the trophic state has on the flora of an aquatic system. It was determined that East Gemini Lake was eutrophic based on its available nutrients and phytoplankton populations. In contrast, Stumpf Lake was determined to be mesotrophic having lower available nutrients and less phytoplankton population density with fewer major phytoplnakton …


Remnant Vegetation Inventory On The Southern Agricultural Areas Of Western Australia., G R. Beeston, G Mlodowski, A Sanders, D True Jan 1995

Remnant Vegetation Inventory On The Southern Agricultural Areas Of Western Australia., G R. Beeston, G Mlodowski, A Sanders, D True

Resource management technical reports

Remnant vegetation mapping and its incorporation into a Geographical Information System (GIS) data base is the first stage in an overall documentation and promotion of conservation of remnant vegetation in Western Australia. The primary objective of this project being to determine the amount, distribution and regional location of native vegetation remaining on private land in the agricultural area of south-west Western Australia.


The Trophic Gradient In Lake Powell, Wayne A. Wurtsbaugh, G. Steinhart Jan 1995

The Trophic Gradient In Lake Powell, Wayne A. Wurtsbaugh, G. Steinhart

Watershed Sciences Faculty Publications

From April 21 st to April 25th, 1995 students from Utah State University's FW 462 class sampled the trophic gradient in Lake Powell between Bullfrog (Mile 99) and Hite Marinas (Mile 144). We sampled at 3-12 stations along the gradient, depending on the parameter measured. The purpose of the trip was three-fold. First, the primary objective of the class was to provide field and laboratory experiences in aquatic ecology for the students. Secondly, we wished to provide data on the trophic environment that the endangered razorback sucker larvae from the Colorado River would encounter when the entered the reservoir. Thirdly, …


Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh Jan 1995

Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (1968) estimated that 4,360 sockeye returned to Redfish Lake in 1955. These numbers no longer exist. In the 1980's, less than 50 . Snake River sockeye salmon survived to spawn (Bowler 1990). Since 1990, only 14 sockeye have returned. Because of recent declines, the Shoshone-Bannock Tribes (SBT) petitioned the National - Marine Fisheries Service (NMFS) to list · Snake River sockeye as endangered. As a result, Snake River sockeye were listed and …


Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service Dec 1994

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …


Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service Dec 1994

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …


Seasonal Composition Of Mesozooplankton In The Pagan River, A Nutrient Enriched Virginia Estuary, Lillian Norman Davis Oct 1994

Seasonal Composition Of Mesozooplankton In The Pagan River, A Nutrient Enriched Virginia Estuary, Lillian Norman Davis

Biological Sciences Theses & Dissertations

A two year study of the mesozooplankton composition and seasonal distribution was conducted in the Pagan River, a nutrient rich tidal estuary and tributary to the lower James River. The mesozooplankton was dominated by calanoid copepods (80%), with the total zooplankton abundance peaks occurring during spring and fall. The total mean abundance, 3008/m', was somewhat lower than those found by other authors, however the mean abundance at one station approximated those means. Seventy-eight percent of the calanoid copepods were Acartia spp. that were primarily responsible for the fall increase in mesozooplankton abundance. The spring increase was primarily due to increases …