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Articles 241 - 270 of 295

Full-Text Articles in Fresh Water Studies

Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead, Allagash Wilderness Waterway Working Group Jan 2007

Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead, Allagash Wilderness Waterway Working Group

Maine History & Policy Development

In his June 19, 2006, Executive Order, Governor John E. Baldacci directed the Working Group to “offer its best guidance and advice to the Governor respecting the long-term governance, management, and oversight structure for the Allagash Wilderness Waterway” (AWW). In the intervening six months the members of the Working Group have engaged in an examination of the forty-year history of the Waterway and an analysis of the conditions and circumstance that led to the Governor’s Executive Order. We have reviewed documentation of the AWW history, taken testimony at numerous public meetings and hearings, conducted correspondence with members of the several …


Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead (Executive Summary), Allagash Wilderness Waterway Working Group Jan 2007

Allagash Wilderness Waterway Working Group On Structure, Management And Oversight: Choosing Common Ground And Moving Ahead (Executive Summary), Allagash Wilderness Waterway Working Group

Maine History & Policy Development

In his June 19, 2006, Executive Order, Governor John E. Baldacci directed the Working Group to “offer its best guidance and advice to the Governor respecting the long-term governance, management, and oversight structure for the Allagash Wilderness Waterway” (AWW). In the intervening six months the members of the Working Group have engaged in an examination of the forty-year history of the Waterway and an analysis of the conditions and circumstance that led to the Governor’s Executive Order. We have reviewed documentation of the AWW history, taken testimony at numerous public meetings and hearings, conducted correspondence with members of the several …


Agricultural Climatology, Kenneth G. Hubbard Jan 2007

Agricultural Climatology, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

With the diversification of the U.S. economy over the past century, agriculture has changed. We can say the farm sizes have increased over time, the number of farmers and those employed in farming have decreased over time, and as the economy has grown the relative contribution of agriculture to the total economy has decreased due to growth in other sectors. The farm prices have not changed significantly over many years while costs for energy, machinery, and land have generally increased. The combination of these factors has generally narrowed the profit margin and the highest productivity will no longer ensure the …


Droughtscape, Winter 2007, Kelly Smith Jan 2007

Droughtscape, Winter 2007, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

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Policy Update: NIDIS is Law. What’s Next?

What Would You Like to See?

TX, OK, Plains, Southwest Hardest Hit in 2006

Climatologically Speaking, How Bad Was It?

State Spotlight: Arizona

Drought Decision-Support Tools Evolving


Augusta Me: The New Bridge Begets A New Planned Neighborhood, Molly Pulsifer, Richard Barringer Aug 2006

Augusta Me: The New Bridge Begets A New Planned Neighborhood, Molly Pulsifer, Richard Barringer

Planning

Construction of a new Third Bridge over the Kennebec River in Augusta offered the prospect of a new and handsome gateway to the city. Further, the resulting change in traffic patterns offered the City the chance to plan for a pattern of development quite different from what the city had experienced for the past half-century. The case study describes the planning and construction of the new bridge and corridors that re-routed traffic out of Augusta’s downtown and older neighborhoods, and created the opportunity for planned development adjacent to the corridor created by the new bridge. It goes on to describe …


Promoting Low Impact Development In Your Community, New England Environmental Finance Center Jan 2006

Promoting Low Impact Development In Your Community, New England Environmental Finance Center

Planning

Low Impact Development (LID) is an approach to stormwater management and site development that is gaining popularity throughout the country. Its attractiveness lies in its potential to lessen off-site stormwater impacts, reduce costs to municipalities and developers, and promote development that is “softer on the land” compared with typical traditional development. The approach, which is applicable to residential, commercial and industrial projects, and in urban, suburban and rural settings, often is linked with efforts by governments and citizens to foster more sustainable communities.


Facilitating The Development Of The Strawberry Industry In Western Australia, Dennis Phillips, Aileen Reid Jan 2006

Facilitating The Development Of The Strawberry Industry In Western Australia, Dennis Phillips, Aileen Reid

Horticulture research reports

Horticulture Australia Project No. BS05001 Annual report 2005/06

This is the first of three annual reports for the Horticulture Australia project BS05001 — ‘Facilitating the development of the strawberry industry in Western Australia’. This project is managed by the Strawberry Growers Association of WA Inc. and the work is being done in collaboration with the Department of Agriculture and Food WA (DAFWA). The project has been funded by voluntary contributions from the W.A. Strawberry Producers Committee, Toolangi Strawberry Runner Growers Co-operative and DAFWA with matching funding from Horticulture Australia Ltd (HAL). The project has been funded for three years, 2005, …


Stormwater Utility Fees: Considerations & Options For Interlocal Stormwater Working Group (Iswg), New England Environmental Finance Center May 2005

Stormwater Utility Fees: Considerations & Options For Interlocal Stormwater Working Group (Iswg), New England Environmental Finance Center

Economics and Finance

Stormwater utilities are a concept whose time seems to have arrived. Established by relatively few communities in the 1970s as a method of funding flood control measures, stormwater utilities now exist in over 400 municipalities and counties throughout the United States. During the next 10 years, their numbers are expected to swell dramatically – by one estimate to over 2,000 by the year 2014.

The reasons for this growth are multifold. Federal stormwater regulations passed in the 1980s (Phase I of the National Pollutant Discharge Elimination System Program, or NPDES), motivated many larger communities to seek alternative funding sources and …


An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mamood, Kenneth G. Hubbard Jan 2004

An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mamood, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

Soil moisture (SM) plays an important role in land surface and atmosphere interactions. It modifies energy balance near the surface and the rate of water cycling between land and atmosphere. The lack of observed SM data prohibits understanding of SM variations at climate scales under varying land uses. However, with simulation models it is possible to develop a long-term SM dataset and study these issues. In this paper a water balance model is used to provide a quantitative assessment of SM climatologies for three land uses, namely, irrigated corn, rain-fed corn, and grass, grown under three hydroclimatic regimes in Nebraska. …


Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson Jan 2002

Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson

High Plains Regional Climate Center: Staff Publications

The North American Great Plains have experienced a rapid overturning of natural grasslands to agricultural land use over the last century. Moreover, in some areas more than 80% of the land use has changed from dry land to irrigated agriculture during the second half of the twentieth century. It is speculated that these changes have modified near-surface atmospheric condition and our modeling study seems to support this. To identify changes in land surface- atmospheric modifications we have applied a soil moistureenergy balance model at three locations in Nebraska: Mead, York, and McCook. The model was applied for three land uses …


Arizona Source Water Assessment Plan Final Draft, Arizona Department Of Environmental Quality Feb 1999

Arizona Source Water Assessment Plan Final Draft, Arizona Department Of Environmental Quality

Publications (WR)

The safe drinking water amendments of 1996 placed a strong emphasis on the goal to establish a nationwide effort to protect drinking water sources. As part of that goal, the legislation provided for a preliminary assessment of drinking water sources and an inventory of surrounding adjacent land use (ALUs). This nationwide effort will result in the first comprehensive look at the nation's drinking water sources from an assessment perspective. One of the outcomes of this nationwide assessment will be information that public water systems (PWSs) can use to help determine appropriate monitoring frequencies and to protect their sources of drinking …


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 …


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 …


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 …


Limiting Growth In Las Vegas - A Necessary Growth Strategy For The Twenty-First Century, Cheryl Ann Frassa Apr 1995

Limiting Growth In Las Vegas - A Necessary Growth Strategy For The Twenty-First Century, Cheryl Ann Frassa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Land development in the Las Vegas Valley continues at an unprecedented rate and future growth will no doubt be strongly advocated. Yet, water resources in this desert area are finite, and in the near future, supply will fall short of demand. Plans are underway to supplement the existing supply, and proposals to secure additional sources are under investigation. But there are no guarantees these ambitious endeavors will materialize. In light of the pending water crisis, the pervasive "growth at all cost" policies now dominant in the valley must be abandoned and more realistic land-use policies developed; ones based on the …


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 …


Bulletin 4279 - Streamlining - An Environmentally Sustainable Drainage Network For The Swan Coastal Plain (Peel-Harvey Catchment), Garry Heady, Neil Guise Aug 1994

Bulletin 4279 - Streamlining - An Environmentally Sustainable Drainage Network For The Swan Coastal Plain (Peel-Harvey Catchment), Garry Heady, Neil Guise

Bulletins 4000 -

Community Catchment Centre Pinjarra

A network of over 1400 kilometres of drains and modified natural waterways constructed by the Public Works Department criss-crosses the Peel-Harvey catchment. There are also over 3300 kilometres of minor drains and natural waterways in this same region.

The expansion of agriculture relied on this extensive drainage network, which was designed to ensure rapid drainage of the region. Unfortunately there was little regard to future environmental consequences.

Along with drainage water, these same drains now carry high loads of silt and nutrients. Many of the drains are also degraded and require expensive maintenance annually.


Ground Water Flow And Water Resources Investigation Of The Auburn, Summers And Shakertown Springs Karst Ground Water Basins, Logan And Simpson Counties, Kentucky, William Howcroft Dec 1992

Ground Water Flow And Water Resources Investigation Of The Auburn, Summers And Shakertown Springs Karst Ground Water Basins, Logan And Simpson Counties, Kentucky, William Howcroft

Masters Theses & Specialist Projects

The City of Auburn is faced with a number of problems relating to its dependency on two karst springs, Auburn and Summers Springs, to meet its water requirements. Besides being extremely vulnerable to contamination, the springs often discharge and insufficient volume of water needed for public consumption and dilution of the City’s treated wastewater. Thus the City wishes to find an additional source of water and views nearby Shakertown Spring as a possibility. The study has three main objectives: 1) delineation of the Auburn, Summers, and Shakertown Springs ground water basins, 2) determination of the volume of available water at …


Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson Jan 1989

Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson

Publications (WR)

Echograms have been used extensively to locate and estimate the relative abundance of marine fish stocks (Cushing 1973). In freshwater, echograms have been used to describe vertical (Netsch et al. 1971; Eggers 1978; O'Brien et al. 1984; Matthews et al. 1985), spatial (O'Brien et al. 1984; Wanjala et al. 1986) and temporal (Baker and Paulson 1983) patterns in fish abundance. Although most uses of echograms have been qualitative, Mullan and Applegate (1969) and Matthews et al. (1985) obtained relative estimates of fish abundance by counting targets (fish) on echograms. However, neither Mullan and Applegate (1969) nor Matthews et al. (1985) …


Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation Jun 1988

Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation

Publications (WR)

A pumped storage system consists of an upper reservoir and lower reservoir separated by an elevation difference. During low demand energy periods such as nights and weekends water is pumped from the lower to the upper reservoir using available energy from conventional steam electric power plants. During high energy demand periods, such as mornings and afternoons of weekdays, upper reservoir water is allowed to drop back down through the same system of water conduits and turbines, generating electricity to conveniently meet abrupt electrical energy requirements. The same water turbines thus act both as pumps and as conventional hydroelectric turbines. Because …


Environmental Assessment Of Las Vegas Wash And Lake Mead Artificial Wetlands Demonstration Project, John R. Baker, R. M. Gersberg, U.S. Environmental Protection Agency Feb 1988

Environmental Assessment Of Las Vegas Wash And Lake Mead Artificial Wetlands Demonstration Project, John R. Baker, R. M. Gersberg, U.S. Environmental Protection Agency

Publications (WR)

The effective use of artificial wetlands for treatment of municipal wastewater is well documented; however, design and economic data for artificial wetlands development are limited (Gersberg et al., 1984a). This is due partly to regional differences in climate, soils, and vegetation and partly to the desired waste treatment. As a result, specific treatment levels and cost benefits relative to the use of an artificial wetlands for a particular site cannot be evaluated adequately without a pilot demonstration project. Las Vegas Wash receives sewage effluent from the Las Vegas metropolitan area and has been designated as a wetlands community park. Las …


River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada Jan 1988

River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada

Publications (WR)

A water quality modeling study of the Mohave Reach of the Lower Colorado River (from Davis Dam to the Nevada/California Stateline) was conducted to evaluate potential water quality impacts resulting from a proposed Laughlin, Nevada wastewater effluent discharge. The study included four major components: (1) review of the current regulatory framework; (2) a field data collection program to document existing water quality conditions in winter, summer, and fall; (3) development and verification of far-field and near-field (mixing zone) water quality models; and (4) application of the models to project future river quality conditions for several treatment-discharge alternatives as well as …


Limnological Monitoring Data For Lake Mead During 1987: Technical Report No. 20, Larry J. Paulson Jan 1988

Limnological Monitoring Data For Lake Mead During 1987: Technical Report No. 20, Larry J. Paulson

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1987. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.


Changes In The Morphometry Of Las Vegas Wash And The Impact On Water Quality, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation Jan 1988

Changes In The Morphometry Of Las Vegas Wash And The Impact On Water Quality, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation

Publications (WR)

Las Vegas Wash, a natural wash east of Las Vegas, Nevada, carries stormwater, groundwater drainage, and sewage effluent from two sewage treatment plants to Lake Mead. Over 80 percent of the normal discharge of approximately 3.4 m3/s (120 ft3/s) consists of effluent from the City of Las Vegas and Clark County sewage treatment plants. Beginning in the 1950s, a large wetland area developed along the wash that supported waterfowl populations and contributed to some water quality transformations. Heavy rains and subsequent flooding in the area in 1983 and 1984 resulted in erosion and channelization that greatly …


Thermal Tolerances And Preferences Of Fishes Of The Virgin River System (Utah, Arizona, Nevada), James E. Deacon, Paul B. Schumann, Edward L. Stuenkel Oct 1987

Thermal Tolerances And Preferences Of Fishes Of The Virgin River System (Utah, Arizona, Nevada), James E. Deacon, Paul B. Schumann, Edward L. Stuenkel

Publications (WR)

Critical thermal maxima (CTM) and thermal preferenda of the common fishes of the Virgin River were examined. Differences in final temperature preferenda and CTM for species with low thermal lability (speckled dace, spinedace, roundtail chub) correspond well with differences in their distribution and abundance in the river. These species shifted their acute thermal preferences relatively little as acclimation temperature increased. For thermally labile species (woundfin, red shiner, desert sucker, and fiannehnouth sucker), the final preferendum is a less precise indicator of probable distribution. The woundfin, an endangered fish, has a high CTM (39.5 C at 25 C acclimation) and a …


Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection May 1987

Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.


A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson Nov 1984

A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson

Publications (WR)

Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m3. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m3. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …


Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde May 1984

Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde

Publications (WR)

Zooplankton samples collected from throughout Lake Mead, in 1981-1982, demonstrate the presence of a statistically significant seasonal and spatial heterogeneity in zooplankton densities. Seasonally, the major zooplankton groups were most abundant in the spring and fall, coincident with maxima in chlorophyll-a concentrations. Successions among the various rotifers, cladocerans and copepods present in the reservoir were influenced by food availability, diapause, predation by planktivorous fish and, possibly, water temperatures. Spatial heterogeneity in zooplankton densities was unrelated to water temperature, pH, conductivity and dissolved oxygen concentrations, but was related to the abundance of phytoplankton (chlorophyll-a concentrations) and fish. Statistical analyses indicate that …