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Articles 1321 - 1350 of 1646

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice Jun 1989

Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice

Arkansas Water Resources Center Technical Reports

An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in …


Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis Jun 1989

Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis

Arkansas Water Resources Center Technical Reports

Cotton (Gossypium hirsutum L) is an important crop in the southern United States. The crop is grown in both irrigated and rainfed situations and is seldom free from periods of water shortages at some stage during the season. In recent years the need for consistency in yields and a stable cash flow has resulted in a rapid expansion in the number of irrigated acres of cotton in the Mississippi Delta. Irrigation research has, however, not kept pace with this expansion. This project represents a start at meeting this urgent need. The influence of weather patterns necessitates that these studies be …


Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott Jun 1989

Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott

Arkansas Water Resources Center Technical Reports

A PC/AT computer model was developed to simulate the transport of water, nitrate and ammonia in the soil profile after an application of poultry litter to pasture. The model was written using FORTRAN 77 compiler and can be used on any IBM type compatible computer with a math coprocessor. Poultry litter has been shown to be a potential source of plant nutrients, but mismanagement can result in nitrate pollution of the surface and groundwater. The model is composed of a main program, 11 subroutines and three subprograms. An example was shown of the flexibility and dynamic nature of the computer …


Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer Jun 1989

Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

A data base of the algae of Arkansas ecoregions has been established to describe the numerous taxa that occur within the aquatic ecosystems included in these regions. The organisms were identified with the aid of diverse literature from throughout the world. These sources are written in multiple languages and the living organisms had to be compared with outline or silhouette drawings. These illustrations may include shading, but none present the true color of the organism but only the characteristics of the descriptive source. Primary characteristics used to identify algae is based upon pigmentation of the plastid and the number and …


Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle Jun 1989

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …


Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection May 1989

Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection

Publications (WR)

In September 1987 the Nevada Division of Environmental Protection revised Water Quality Standards for Las Vegas Wash (LVW) and Lake Mead. Standards were set for chlorophyll-a and unionized ammonia in Las Vegas Bay (LVB) (NDEP 1987). The 1986 and 1987 LVB data showed non-achievement of both the chlorophyll-a and unionized ammonia standard which triggered an analysis of total phosphorus and total ammonia Total Maximum Daily Loads and Waste Load Allocations which are presented in this report. This report is separated into three sections: 1. 1987 Las Vegas Bay Water Quality Conditions and Seasonal Periodicity. 2. Concentration Estimates at Northshore Road …


Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection Apr 1989

Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1988. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading and increased ammonia in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.


Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife Mar 1989

Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife

Publications (WR)

Red swamp crayfish (Procambarus clarkii) were trapped in Flamingo Wash, an urban wash of Las Vegas, during four periods of 1988. Life history and reproductive success were determined. The trapped crayfish were marked and released into a study cove in Lake Mead as part of an experimental stocking program. Retrap data from the study cove were used to determine life history, habitat preferences, and movement patterns of the stocked crayfish. In addition, a literature search was done on red swamp crayfish ecology, including food preferences, life history, habitat preferences and fish predation.


Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore Jan 1989

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore

Arkansas Water Resources Center Technical Reports

River water samples from the five sites were collected by the U. S. Geological Survey (USGS) in accordance with their established sampling procedures. Samples for wet chemistry and atomic absorption analyses were delivered to the Bell Engineering Center at the University of Arkansas by USGS personnel. Samples for organics analyses from the Lee Creek, Dardanelle, Little Rock and Pine Bluff sites were delivered by USGS to American Interplex in Little Rock. Samples for organics analyses for the Van Buren site were delivered to the Bell Engineering Center and sent by United Parcel Service (next day air) to Daily Analytical Services …


Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control Jan 1989

Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control

Maine Collection

Maine Nonpoint Source Pollution Assessment Report

Prepared by the Maine Department of Environmental Protection, Bureau of Water Quality Control, Augusta, Maine 1989.

Contents: Executive Summary / Introduction / Methodology / Statewide Water Quality Summary / State And Local Agency Programs for Control of Nonpoint Source Pollution / Process for Identification of Best Management Practices and Associated Standards / List of References / List of Figures / List of Tables



Introducing Onslow, Western Australian Department Of Agriculture Jan 1989

Introducing Onslow, Western Australian Department Of Agriculture

Grain and other field crops published reports

Onslow Barley........ a new breed of barley for the southern high rainfall areas (see map VH,H4 &H5). Suited to May plantings, Onslow is the first barley developed specifically for the long growing seasons in these areas.

For the first time barley growers have a variety designed for those 4 t/ha plus yields which research shows are possible with early sowing.

Onslow is the first of a new breed of barley cultivars developed in Western Australia specifically for the southern high rainfall areas which have a long growing season.


Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta Aug 1988

Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta

Arkansas Water Resources Center Technical Reports

This user’s guide supports the use of VILMA (Virtually Interactive Large-scale Model for Arkansas). This document presents the basic concepts in Chapter I. Chapter II discusses the execution steps that the user follows during a VILMA session. Chapter III provides a detailed illustration of example data files. Chapter IV presents two example VILMA sessions. Finally, Chapter V elaborates on additional concepts. The Appendices consist of relevant program listings, instructions, and example files. In this user’s guide, the word "interactive" means the user enters his responses to the prompts that appear on a computer terminal while he is logged on to …


Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale Jun 1988

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale

Arkansas Water Resources Center Technical Reports

In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …


Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis Jun 1988

Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis

Arkansas Water Resources Center Technical Reports

Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …


Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer Jun 1988

Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

A data base of the algae of Arkansas ecoregions has been estabblished by the use of a relational data base management system (dBase III plus). The system was chosen to be readily available for a variety of microcomputers using MS- and PC-DOS. The data base contains taxonomic fields from division through variety, synonymy, authors, initial description, date, and definitive descriptive source. The data are cross-referenced by ecoregion, Round's community and subcommunity designations. The data base contains greater than 1,500 taxonomic records in all divisions and classes of freshwater algae. The data are sortable by any of the included parameters. The …


Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr Jun 1988

Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr

Arkansas Water Resources Center Technical Reports

A 281-year reconstruction of White River annual runoff at Clarendon, Arkansas, was developed from a regional average of nine Oklahoma, Missouri, and Arkansas tree-ring chronologies (six post oak, Quercus stellata, and three baldcypress, Taxodium distichum). Inhomogeneity of the gaged series was detected with both double mass analysis (using state average total annual Arkansas precipitation) and regression (using the regional tree-ring average). Simple regression calibrated the homogeneous runoff data with the average ring width data from 1930 to 1980. Comparing the reconstruction with independent data verified the regression model. Variance of the reconstruction increases significantly during the 20th century, a change …


Drought Management: The Role Of Near- Real Time Weather Data, Donald A. Wilhite, Kenneth G. Hubbard Jan 1988

Drought Management: The Role Of Near- Real Time Weather Data, Donald A. Wilhite, Kenneth G. Hubbard

National Drought Mitigation Center: Faculty Publications

The ability to collect weather data in near-real time has improved because of technological advances, enabling weather data users to obtain more weather data over wider areas, and in a more timely fashion. The number of near-real time climate networks is increasing as new applications are found for climate data. More than fifteen states in the United States have established automated weather station networks. This paper presents an overview of recent developments in automated weather data collection in the United States and gives a detailed description of the network in Nebraska.

Near-real time weather data has many applications in agricultural …


Cropstatus--A Computer Program To Assess The Effects Of Seasonal Weather Changes On Nebraska's Agriculture, R. E. Neild, Donald A. Wilhite, K. G. Hubbard Jan 1988

Cropstatus--A Computer Program To Assess The Effects Of Seasonal Weather Changes On Nebraska's Agriculture, R. E. Neild, Donald A. Wilhite, K. G. Hubbard

National Drought Mitigation Center: Faculty Publications

CROPSTATUS is a series of programs residing in Nebraska's AGNET system using daily weather data to assess seasonal changes in crops, livestock, and other agricultural conditions. Assessments are based on parameters developed from accumulations of current daily temperature and precipitation data collected from a network of synoptic, climate, and automated micrometeorological stations in Nebraska in comparison with daily normals. The daily normals were derived from monthly summaries using multiple regression models to compute daily values as a function of Julian day numbers. Crop phenology models based on growing degree days were used to monitor and forecast the progress of different …


Improving Projected Potential Evapotranspiration Estimates Using National Weather Service Forecasts, Steven J. Meyer, Kenneth G. Hubbard, Donald A. Wilhite Jan 1988

Improving Projected Potential Evapotranspiration Estimates Using National Weather Service Forecasts, Steven J. Meyer, Kenneth G. Hubbard, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

In a recent survey conducted by the University of Nebraska's Center for Agricultural Meteorology and Climatology of Agricultural Network (AGNET) users, the results of potential evapotranspiration (ETp) projections (calculated using the Blaney-Criddle approach, which employs "normal" climatic data to project ETp estimates up to three days into the future) were labeled "unrealistic." To improve these projections, National Weather Service (NWS) forecast variables were used as input into the Blaney-Criddle and Penman equations. ETp projections calculated according to the Penman equation, with data measured by automated weather stations as input, were assumed to represent the "best" …


The Nebraska Agricultural Climate Situation Committee, R. E. Neild, K. G. Hubbard, Donald A. Wilhite Jan 1988

The Nebraska Agricultural Climate Situation Committee, R. E. Neild, K. G. Hubbard, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

The Nebraska Agricultural Climate Situation Committee consisting of an interdisciplinary group of extension specialists provides up-to-date information and advice on seasonal changes in crop/ weather conditions. The committee meets each Monday during the growing season to review:

1. Maps and tabular data developed by a computer program CIS /Crop Weather Information System/ that is linked to a network of weather stations and computer terminals in county agent offices.

2. Insect, plant disease and weed surveys.

3. Weekly weather and crop reports from the State/Federal System.

4. Weather outlooks from the National Weather Service.

5. Climate probabilities.

Situation reports and advisories …


Fish Aid: The Lake Mead Fertilization Project, Richard Axler, Larry Paulson, Peter Vaux, Patrick Sollberger, Donald H. Baepler Jan 1988

Fish Aid: The Lake Mead Fertilization Project, Richard Axler, Larry Paulson, Peter Vaux, Patrick Sollberger, Donald H. Baepler

Publications (WR)

Sport fishing at Lake Mead in Nevada and Arizona is a resource valued at nearly $100 million per year to southern Nevada. During the past two decades, salmonids, mostly trout, have disappeared entirely, the largemouth bass catch has drastically declined despite greater fishing pressure, and the condition factors for striped bass have steadily deteriorated. It appears that a major reduction in phosphorus loading caused by the upstream impoundment of the Colorado River to form Lake Powell in 1963 and advanced wastewater treatment removal of phosphorus from domestic wastewater inflows in 1981 are the principal factors responsible for decreased production at …


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 …


Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation Nov 1987

Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation

Publications (WR)

Studies conducted by the University of Nevada-Las Vegas (UNLV), the Nevada Department of Wildlife (NDOW), the Arizona Game and Fish Department (AGFD), The Nevada Division of Environmental Protection (NDEP), and the United States Bureau of Reclamation (USBR) have identified decreased algal production as a major factor involved in the decline of the Lake Mead sport fishery. Phosphorus-laden silt particles in the Colorado River have been sedimenting out in Lake Powell since the completion of Glen Canyon Dam 286 miles upstream in 1963. This sharp decrease in phosphorus loading to Lake Mead (>5000 tons per year) has resulted in decreased …


Benthic Invertebrates And Crayfish Of Lake Mead, Susan K. Peck, William L. Pratt, James E. Pollard, Larry J. Paulson, Donald H. Baepler Sep 1987

Benthic Invertebrates And Crayfish Of Lake Mead, Susan K. Peck, William L. Pratt, James E. Pollard, Larry J. Paulson, Donald H. Baepler

Publications (WR)

The objectives of this study were to:

1. Establish baseline densities of benthic invertebrates and relative abundance of crayfish in Lake Mead.

2. Evaluate the distributions of benthic organisms and crayfish in relation to existing habitat conditions and 1imnological characteristics of Lake Mead.

3. Measure seasonal changes in abundances of benthic organisms and crayfish in Lake Mead.

4. Compare observations of Procambarus clarkii life history in Lake Mead to reports from other aquatic systems.

5. Evaluate the importance of benthic organisms and crayfish as food sources for game fish in Lake Mead.


Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen Aug 1987

Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen

Publications (WR)

In February, 1982 I began a year-long study to determine if growth and reproduction in Daphnia Pulex were limited by the amount of food available in Boulder Basin, Lake Mead. To determine this, I made monthly collections of Daphnia Pulex and natural lake seston from an already established station in Boulder Basin. I cultured the Daphnia Pulex under simulated field conditions in a flow-through feeding apparatus using four different food regimes; 1-natural lake seston filtered through 80 um mesh to remove other zooplankton, 2-lake seston (as above) with an enrichment of 103 cells-ml-1 of Chlamydomonas reinhardti, 3-lake …


Appendices To Analysis Of The Water-Quality Standards Proposed By Nevada Division Of Environmental Protection, State Of Nevada: Division Of Environmental Protection Aug 1987

Appendices To Analysis Of The Water-Quality Standards Proposed By Nevada Division Of Environmental Protection, State Of Nevada: Division Of Environmental Protection

Publications (WR)

The appendices include the following: Appendix A: Evaluation of proposed State of Nevada water quality standards for Ammonia, produced by CH2M Hill California for Clark County Appendix B: Responses to comments by the Nevada Division of Environmental Protection on the draft final report prepared by CH2M Hill Appendix C: Biases in the ammonia data and in the proposed ammonia TMDL Appendix D: Application of dilution-ratio analysis to assertions made by the Nevada Division of Environmental Protection Appendix E: Analysis of the dilution-ratio formula used by the Nevada Division of Environmental Protection in its TMDL calculations for phosphorus and ammonia in …


Movement And Transformation Of Selected Organic Pollutants In Subsurface Environmet In Arkansas, Ali U. Shaikh Jun 1987

Movement And Transformation Of Selected Organic Pollutants In Subsurface Environmet In Arkansas, Ali U. Shaikh

Arkansas Water Resources Center Technical Reports

Several subsurface soil and groundwater samples from eastern, southern and central Arkansas were analyzed for chlorinated organic compounds commonly used as pesticides and industrial chemicals. No significant amount of these compounds were found in these samples. The adsorption/partition characteristics of some of these compounds, such as dichlorophenols, aldrin and endrin, were determined in siltloam, sandyloam and clay soils collected from the above geographical locations. Results indicate that there is considerable difference in retention capability of different types of soils with respect to different pollutants. The partition coefficient of a particular compound in a certain type of soil can be related …


Assessment Of The Effects Of Household Chemicals Upon Individual Septic Tank Performances, Mark A. Gross Jun 1987

Assessment Of The Effects Of Household Chemicals Upon Individual Septic Tank Performances, Mark A. Gross

Arkansas Water Resources Center Technical Reports

A laboratory study and a field study were performed to determine the amounts of specific household chemicals required to destroy bacteria populations in individual domestic septic tanks. The particular chemicals evaluated include liquid chlorine bleach, High Test Hypochlorite (HTH), Lysol disinfectant and Drano crystal. The laboratory study was performed to determine the approximate chemical concentrations to destroy the bacteria in the septic tank, and the field study showed the actual effect of the chemicals upon the bacteria in terms of reduction of the number of bacteria in the septic tank as well as the time required for the bacterial population …


Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale Jun 1987

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale

Arkansas Water Resources Center Technical Reports

In 1985, more than 750 million broiler chickens were produced in Arkansas. During the same year over 15 million laying chickens produced 3.6 million eggs. The waste products of these agricultural production systems, poultry litter and manure, were about 1 million metric tons. As a result of land application of these wastes, about 5,000 metric tons of annnonium N and 12,000 metric tons of mineralized nitrogen were applied to Arkansas pastures in 1985. Manures contributed about 2-3 percent of the total. The objective of this research was to quantify major components of the nitrogen cycle which influence the ground and …


Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends- Iii, Richard L. Meyer Jun 1987

Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends- Iii, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

A data base of the algae of Arkansas ecoregions has been established by the use of a relational data base management system (dBase III plus). The system was chosen to be readily available for a variety of microcomputers using MS- and PC-DOS. The data base contains taxonomic fields from division through variety, synonymy, authors, initial description, date and definitive descriptive source. The data are cross-referenced by ecoregion, Round's community and subcommunity designations. The data base contains approximately 1,500 taxonomic records in all divisions and classes of freshwater algae. The data are sortable by any of the included parameters. The data …