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13.4.9. Preliminary Considerations For Manipulating Vegetation, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.4.9. Preliminary Considerations For Manipulating Vegetation, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

A wide diversity of plants has adapted to the dynamic nature of wetlands. The continually changing floral landscape is shaped by physical or abiotic components that include climate, fire, soil, and water. Water quantity, quality, and chemistry have a dominating influence on wetlands as do factors such as hydroperiod (period when soils are saturated) and hydrological regime. Other factors that may affect the abundance, structure, and species composition of macrophytes or robust emergents are natural grazing, disease, and interspecific plant competition.

Vegetation is important to waterfowl for producing seeds, tubers, and browse; providing nest sites; and serving as substrates for …

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13.1.1. Nutritional Values Of Waterfowl Foods, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.1.1. Nutritional Values Of Waterfowl Foods, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

Over 40 species of North American waterfowl use wetland habitats throughout their annual cycles. Survival, reproduction, and growth are dependent on the availability of foods that meet nutritional requirements for recurring biological events. These requirements occur among a wide variety of environmental conditions that also influence nutritional demands. Recent work on nesting waterfowl has identified the female’s general nutrient needs for egg laying and incubation. Far less is known about nutritional requirements for molt and other portions of the life cycle, particularly those during the non-breeding season. Although information on specific requirements for amino acids and micronutrients of wild birds …

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Complete Waterfowl Management Handbook Jan 1988

Complete Waterfowl Management Handbook

Waterfowl Management Handbook

The North American Waterfowl Management Plan, the Service's most recent mandate for management of migratory waterfowl, and recent legislation such as the Farm Bill all underscore the need for a single source of information about the management of waterfowl and their habitat. Much of this information exists in scientific papers, unpublished reports, or has never been recorded, and thus is not readily accessible by waterfowl managers. The need for a waterfowl management handbook was originally suggested to the Office of Information Transfer by personnel in the Service's north-central region. A prototype handbook was developed in 1987 and critiqued by 38 …

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The Effect Of Grass Carp Introduction On Aquatic Vegetation And Existing Fish Populations In Two Small Prairie Lakes, David L. Bauer Jan 1988

The Effect Of Grass Carp Introduction On Aquatic Vegetation And Existing Fish Populations In Two Small Prairie Lakes, David L. Bauer

Electronic Theses and Dissertations

Within two years after triploid grass carp introduction in 2.3 hectare Prior Lake in South Dakota, aquatic vegetation coverage and height in the water column were significantly lower (P<0.005). During the same two year period, triploid grass carp did not significantly reduce aquatic vegetation coverage or height in the water column in 11.4 hectare East Lake Eureka, also in South Dakota. Stocking densities were 49 fish/hectare and 61 fish/hectare (229 mm mean total length) in Prior Lake and East Lake Eureka, respectively. The biomass of prey fish in East Lake Eureka in 1986 was quite high with 88.3, 85.3 and 17.3 kg/hectare for black bullhead (Ictalurus melas), yellow perch (Perea flavescens), and bluegill (Lepomis macrochirus), respectively. The biomass of northern pike (Esox lucius) was also high at 13.8 kg/hectare. A Proportional Stock Density (PSD) of 11 and Relative Weight (WK) of 117 indicated a relatively healthy bluegill population in East Lake Eureka. However, the PSD value for black bullheads was lower (8) while their condition was relatively good (K=l.58). The yellow perch population appeared to be over-populated in East Lake Eureka with a PSD of only 5 and a relatively low condition factor (K=l.14). The northern pike population in East Lake Eureka had a PSD value of 53, but a slightly low Wr of 94. Available prey/predator ratio indicated that there was an excess of prey fish for most size classes of predators. Because no significant vegetation reduction occurred in East Lake Eureka, no changes in existing fish populations could be attributed to grass carp introduction or aquatic vegetation reduction. Data gathered on existing fish populations in East Lake Eureka will serve as a pre-treatment data set to be compared to future conditions if aquatic vegetation is reduced. Fish sampling in Prior Lake was greatly reduced due to a winterkill which occurred in the late winter of 1986. Bluegill and largemouth bass (Micropterus salmoides) were the most abundant fish species found in Prior Lake in 1987. Bluegill appeared to be overpopulated as their PSD value was 1; a high Wr of 109 may have indicated improved conditions immediately following the winterkill. Results for the largemouth bass in Prior Lake were similar with a low PSD (7) and a high w~ (112). Winterkill (Prior Lake) and lack of aquatic vegetation control by grass carp (East Lake Eureka) prohibited making conclusions about the effect of grass carp introduction on the existing fish populations in the two lakes. Further research needs to be conducted in South Dakota to determine appropriate grass carp stocking rates for South Dakota waters, and to evaluate what effect grass carp introduction and aquatic vegetation reduction has on existing fish populations.

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Electrophoretic, Morphometric, And Meristic Comparisons Of Walleye Broodstock In South Dakota, Chantel M. Waltner Jan 1988

Electrophoretic, Morphometric, And Meristic Comparisons Of Walleye Broodstock In South Dakota, Chantel M. Waltner

Electronic Theses and Dissertations

Electrophoretic and morphological variability among walleyes collected from three upper Missouri River tributaries and a glacial lake in South Dakota was investigated, and an upper Mississippi River stock was electrophoretically compared to the South Dakota stocks. Allele frequencies of two (MDH-3, GMP-3) of the twenty-one loci examined differed significantly (P<0. 05) between South Dakota and Mississippi River walleyes. Contingency chi-square tests of allele frequencies showed homogeneity among walleyes from the Missouri River tributaries, and significant (P<0.001) heterogeneity (P<0.001) at the GMP-3 locus between Missouri River and glacial lake stocks. A dendogram derived from Nei unbiased genetic identity values produced separate branchings for the South Dakota and Mississippi River walleyes. All four walleye stocks in South Dakota were morphologically variable, although no one character could be used as a diagnostic tool to separate the stocks visually. Discriminant function analysis of eight of the most powerful discriminatory characters was successful in correctly classifying walleyes by origin with 83-97% accuracy.

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Growth, Survival, And Vulnerability To Predation Of Stocked Walleye (Stizostedion Vitreum) Fingerlings, James D. Wolters Jan 1988

Growth, Survival, And Vulnerability To Predation Of Stocked Walleye (Stizostedion Vitreum) Fingerlings, James D. Wolters

Electronic Theses and Dissertations

In laboratory tanks, largemouth bass (Micropterus salmoides) and northern pike (Esox Lucius consumed fathead minnows (Pimephales promelas) 2.6 times more frequently than walleye (Stizostedion vitreum) and 5.7 times more than lepomids. Prey were more vulnerable in circular than rectangular tanks. In field studies, walleye fingerlings averaging 35 mm and 53 mm (mean total length) were stocked in two ponds (3- and 7- hectares) respectively: both contained largemouth bass, northern pike, yellow perch (Perca flavescenes), green sunfish (Lepomis cyanellus), and fathead minnows. Aquatic insects dominated the diet of largemouth bass for 3 days after walleye were stocked, indicating that walleye fingerlings …

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Waterfowl Production On Three Types Of Artificial Nesting Structures In South Dakota Wetlands, Marcy Haworth Jan 1988

Waterfowl Production On Three Types Of Artificial Nesting Structures In South Dakota Wetlands, Marcy Haworth

Electronic Theses and Dissertations

Artificial nesting structures are currently being used by various agencies to offset the decline in waterfowl production due to predation losses and degradation of nesting habitats. However, the various structure types available are not equally attractive to nesting waterfowl. This study looked at 3 types of artificial nesting structures – open topped cone baskets, round hay bales, and concrete culverts – and evaluated their used, success, and production in South Dakota. Structure type and site characteristics were correlated to occupancy rates and nesting success. Sixty-eight baskets and 205 bales were monitored during 1986, and 154 baskets, 200 bales, and 20 …

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Forage Potential Of Seasonal Wetlands, Daniel Edward Hubbard Jan 1988

Forage Potential Of Seasonal Wetlands, Daniel Edward Hubbard

Electronic Theses and Dissertations

Investigations on aspects of seasonal wetland forage potential were conducted in eastern South Dakota. The quantity and quality of the standing crop of vegetation in 6 seasonal wetland communities were assessed at the end of the growing season in 1983 and in 2 seasonal-wetland-dominated basins and their associated uplands (native mixed-grass prairie) over the growing season in 1985. Crude protein (CP), ash, detergent fiber, and in vitro digestible dry matter (IVDDM) values were measured on the above-ground material of whitetop [Scolochloas festucacea (Willd.) Link], slough sedge (Carex atherodes Spreng.), burred (Spargnaium eurycarpum Engelm.), and smartweed (Polygonum amphibium L. var. emersum …

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Productivity, Movements, And Habitat Use Of Nesting And Brooding Wild Turkey Hens In Gregory County, South Dakota, Keith Stephen Day Jan 1988

Productivity, Movements, And Habitat Use Of Nesting And Brooding Wild Turkey Hens In Gregory County, South Dakota, Keith Stephen Day

Electronic Theses and Dissertations

Radio-equipped wild turkey (Meleagris gallopavo) hens (n=53) were monitored in a prairie river breaks environment in south-central South Dakota during 1986 and 1987. Seventy percent (36 of 47 adults and 1 of 6 juveniles) of the monitored hens nested. Hens that nested prior to 7 May selected nest sites in woodland habitats, while hens nesting later than 7 May selected nest sites in grassland habitats. Hens nested at sites with higher (P<0.05) percent visual obstruction, percent shrub cover, presence of overhanging vegetation, and habitat diversity than found at random control sites. Nest sites also allowed greater field of vision and opportunities for escape than random controls. Discriminant models developed from variables measured at nest and control sites were effective in distinguishing between the 2 categories. Seventeen of 39 (43.6%) clutches hatched, and 11 broods survived to mid-August. Poult survival in 1986 was 42.9%, with all poult mortality occurring during the first 2 weeks post-hatch. Accurate data for poult survival was not obtainable during 1987, but survival appeared to be similar to 1986. Broods moved up to 3.5 km from nest sites before establishing definite ranges. Broods ranges were composed of ≥50% woodland types, while woodlands comprised only 30.8% of the study area. Mean range size increased 3-fold from the 0-4 week age class (Age 1) to the 4+ week age class (Age 2). Broods used habitats in proportion to availability within ranges. However, grasslands were used more than expected (P<0.05) between 0631 hr and 1130 hr over the summer, and less than expected (P<0.05) by Age 2 broods between 1131 hr and 1630 hr. Woodlands were used more than expected between 1131 hr and 1630 hr over the summer, but not significantly so. Seventy-seven percent of all brood sightings made between 0631 hr and 1130 hr, and 67% of all sightings made between 1631 hr and 2030 hr were in grassland habitats. Seventy-two percent of all brood sightings made between 1131 hr and 1630 hr were in woodlands. Grassland brood use sites had greater forb cover, less grass cover, and were closer to habitat edges than random control sites (P<0.05). Discriminant analysis effectively reclassified grassland brood use sites, but not control sites. Age 1 broods sued grassland sites with greater overhead (> 30 cm) shrub cover, and nearer habitat edges than sites used by Age 2 broods (P<0.05). Woodland brood use sites were nearer (P<0.05) habitat edges than random controls. No significant differences could be found between woodland sites used by Age 1 and Age 2 broods. Discriminant analysis was ineffective in distinguishing between classes for woodland brood use sites or between ages for either woodland or grassland brood use sites.

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A Mass Mortality Of Fishes In Lake Titicaca (Peru-Bolivia) Associated With The Protozoan Parasite Ichthyophthirius Multifiliis, Wayne A. Wurtsbaugh, R. Alfaro Jan 1988

A Mass Mortality Of Fishes In Lake Titicaca (Peru-Bolivia) Associated With The Protozoan Parasite Ichthyophthirius Multifiliis, Wayne A. Wurtsbaugh, R. Alfaro

Watershed Sciences Faculty Publications

In December 1981 , an epizootic of the protozoan parasite Ichthyophthirius multifiliis killed an estimated 18 million killifish Orestias spp. in Lake Titicaca, a high-altitude tropical system. Of the dead fish collected, 93% were adult O. agassii, a commercially important species that is abundant in the littoral zone. Juvenile Orestias spp., pelagic species, and some other littoral zone fis hes were slightly affected. lchthyophthirius multifiliis was probably introduced with exotic fishes brought to Lake Titicaca in the 1940s and 1950s.

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Predicting Potential Aluminum Contamination Of Surface And Ground Waters From Acid Sulfate Enriched Drainages Emanating From Low Neutralization Capacity Watersheds, Anastasios D. Karathanasis, Vasilios P. Evangelou, Y. L. Thompson Jan 1988

Predicting Potential Aluminum Contamination Of Surface And Ground Waters From Acid Sulfate Enriched Drainages Emanating From Low Neutralization Capacity Watersheds, Anastasios D. Karathanasis, Vasilios P. Evangelou, Y. L. Thompson

KWRRI Research Reports

The composition of soil solutions and surface waters emanating from unreclaimed, or partially reclaimed, strip-mined watersheds with low buffering capacity in Kentucky were compared with soil solution compositions of unaffected strata in the watershed. The data suggest that almost 20 years after mining, most soil solutions and surface waters of the disturbed areas still contain high levels of dissolved Al, controlled primarily by the solubilities of a jurbanite-like mineral (upper limit) and alunite (lower limit). Soluble Al in solutions of undisturbed areas was consistent with the solubility of kaolinite or gibbsite. The absence of jurbanite x-ray diffraction peaks suggested the …

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Predicting Potential Aluminum Contamination Of Surface And Ground Waters From Acid Sulfate Enriched Drainages Emanating From Low Neutralization Capacity Watersheds, Anastasios D. Karathanasis, Vasilios P. Evangelou, Y. L. Thompson Jan 1988

Predicting Potential Aluminum Contamination Of Surface And Ground Waters From Acid Sulfate Enriched Drainages Emanating From Low Neutralization Capacity Watersheds, Anastasios D. Karathanasis, Vasilios P. Evangelou, Y. L. Thompson

KWRRI Research Reports

The composition of soil solutions and surface waters emanating from unreclaimed, or partially reclaimed, strip-mined watersheds with low buffering capacity in Kentucky were compared with soil solution compositions of unaffected strata in the watershed. The data suggests that almost 20 years after mining, most soil solutions and surface waters of the disturbed areas still contain high levels of undissolved Al, controlled primarily by the solubilities of a jurbanite-like material (upper limit) and alunite (lower limit).

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Conservation Of Least Terns And Piping Plovers Along The Missouri River And Its Major Western Tributaries In South Dakota, Monica Jean Schwalbach Jan 1988

Conservation Of Least Terns And Piping Plovers Along The Missouri River And Its Major Western Tributaries In South Dakota, Monica Jean Schwalbach

Electronic Theses and Dissertations

Interior least terns (Sterna antillarum) and piping plovers (Charadrius melodus) are listed as endangered or threatened over all of their breeding range, including South Dakota (SD). Investigations were made into the status, distribution, production, habitat characteristics, and factors limiting productivity of least terns and piping plovers in SD. The study area included the Missouri River from the North Dakota state line to Ponca State Park, Nebraska, and the lower 1/3 of the Grand, Moreau, Cheyenne, and White rivers. Least tern numbers increased substantially (253; 367) between 1986 and 1987, but plover numbers increased only slightly (187; 197). Terns and plovers …

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Wetland Characteristics Of Avian Cholera Outbreaks And Surface Water Transfer In The Nebraska Rainwater Basin Area, Brian J. Smith Jan 1988

Wetland Characteristics Of Avian Cholera Outbreaks And Surface Water Transfer In The Nebraska Rainwater Basin Area, Brian J. Smith

Electronic Theses and Dissertations

Avian Cholera (Pateurella multocida) has infected and killed thousands of migrating waterfowl each year since 1975 in Nebraska’s rainwater basin area. Disease outbreaks in migrating waterfowl populations just prior to the nesting season are of concern to biologists. Feedlots and itner-wetland basin surface water transfer mechanisms of the avian cholera causative agent, P. multocida, were investigated using remote sensing techniques. Wetland basin characteristics (classification type, adjacent landuse, basin landuse, and basin densities) were also investigated for relationships to 1981 avian cholera outbreaks. No surface drainage relationships were found that would permit the transfer of P. multocida from one wetland basin …

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Production Of Triploid Rainbow Trout For Evaluation In South Dakota Waters, Jeff C. Dillon Jan 1988

Production Of Triploid Rainbow Trout For Evaluation In South Dakota Waters, Jeff C. Dillon

Electronic Theses and Dissertations

In September 1986, approximately 50,000 rainbow trout (Salmo gairdneri) eggs were fertilized and subjected to heat shocks to prevent expulsion of the second polar body, theoretically resulting in triploid embryos. Heat shocks were at 26 and 28°c, began 10, 20, 30, or 40 min after fertilization, and lasted for 10 or 20 min for a total of 16 treatments. Another 25,000 eggs served as controls and were handled identically but at a normal water temperature of 12°c. Cumulative hatching rates for eggs that were heat-shocked at 26 and 28° were 64 and 50%, respectively, compared to control eggs which had …

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Seasonal Habitat Use, Home Range, And Dispersal Of Wild Turkeys In Southcentral South Dakota, Scott L. Laudenslager Jan 1988

Seasonal Habitat Use, Home Range, And Dispersal Of Wild Turkeys In Southcentral South Dakota, Scott L. Laudenslager

Electronic Theses and Dissertations

Seasonal movements, home range, and habitat use of wild turkeys in south-central South Dakota were investigated using radio telemetry from summer 1984 to winter 1986. Spring dispersal from wintering sites ranged from 0.2 to 5.8 km (x = 2.8 km). Non-nesting females moved significantly (P ~ 0.05) farther than males. Fall movements from summer to winter habitat ranged from o.o to 5.0 km (x = 2.2 km). Marked birds always returned to summer areas used in previous years. In contrast, wintering areas changed yearly among some individuals. Home ranges for all birds in summer ranged from 46. 7 ha to …

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Great Salt Lake Interisland Diking: Water Quality Considerations, John I. Blandamer, William J. Doucette, Ryan R. Dupont, Anthony W. Grover, James Herrick, Jean M. Ihnat, Joan E. Mclean, Michael W. Nath, Samuel R. Rushforth, Judith L. Sims, Ronald C. Sims, Wayne A. Wurtsbaugh Jan 1988

Great Salt Lake Interisland Diking: Water Quality Considerations, John I. Blandamer, William J. Doucette, Ryan R. Dupont, Anthony W. Grover, James Herrick, Jean M. Ihnat, Joan E. Mclean, Michael W. Nath, Samuel R. Rushforth, Judith L. Sims, Ronald C. Sims, Wayne A. Wurtsbaugh

Reports

No abstract provided.

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Friction Factor Tests On High Density Polyethylene Pipe, Steven L. Barfuss Jan 1988

Friction Factor Tests On High Density Polyethylene Pipe, Steven L. Barfuss

Reports

No abstract provided.

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Great Salt Lake Interisland Diking: Water Quality Considerations, Executive Summary, Utah Water Research Laboratory, J. P. Riley, J. I. Blandamer, W. J. Doucette, R. R. Dupont, A. W. Grover, J. Herrick, J. M. Ihnat, J. E. Mclean, M. W. Nath, S. R. Rushforth, J. L. Sims, R. C. Sims, W. A. Wurtsbaugh Jan 1988

Great Salt Lake Interisland Diking: Water Quality Considerations, Executive Summary, Utah Water Research Laboratory, J. P. Riley, J. I. Blandamer, W. J. Doucette, R. R. Dupont, A. W. Grover, J. Herrick, J. M. Ihnat, J. E. Mclean, M. W. Nath, S. R. Rushforth, J. L. Sims, R. C. Sims, W. A. Wurtsbaugh

Reports

No abstract provided.

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Stochastic Interpolation Of Precipitation Data From Multiple Sensors, D. J. Seo, A. Azimi-Zonooz, D. S. Bowles, W. F. Krajewski, C. J. Duffy, K. P. Georgakakos, T. H. Lee Jan 1988

Stochastic Interpolation Of Precipitation Data From Multiple Sensors, D. J. Seo, A. Azimi-Zonooz, D. S. Bowles, W. F. Krajewski, C. J. Duffy, K. P. Georgakakos, T. H. Lee

Reports

Introduction: This report summarizes the work conducted under Grant No. ECE-8419189, "Stochastic Interpolation of Precipitation Data from Multiple Sensors," which was awarded to Utah State University in September, 1985, and completed February 29, 1988. it also covers work under a supplemental award made in February, 1986. The final report is organized into four sections. The following section presents the objective of the research and a brief problem statment. Section 3 contains a summary of second-year work including the project team, work plan, work completed, and publications. In Section4, project conclusions are summarized. A summary of on-going future work is given …

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Carbon Dioxide Emissions And Fossil Fuel Consumption A Canadian Perspective, John Peter Doucet Jan 1988

Carbon Dioxide Emissions And Fossil Fuel Consumption A Canadian Perspective, John Peter Doucet

Theses and Dissertations (Comprehensive)

The potential climate change due to increased loading of carbon dioxide in the atmosphere has emerged as one of the most significant environmental threats of the late twentieth century. An analysis of a variety of feasible energy demand scenarios for Canada indicates that if we continue to consume the same types and proportions of fuels as we do today, the expected demand for energy in the year 2005 would yield carbon dioxide emissions up to 52.5 per cent greater than that of 1985. On the other hand, if Canada were to alter the types and quantities of fuels required to …

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Proceedings Of The 1987 Airlie House Conference On The Resources Planning Act, Clark S. Binkley, Ed, Garry D. Brewer, Ed., V. Alaric Sample, Ed. Jan 1988

Proceedings Of The 1987 Airlie House Conference On The Resources Planning Act, Clark S. Binkley, Ed, Garry D. Brewer, Ed., V. Alaric Sample, Ed.

Yale School of the Environment Bulletin Series

No abstract provided.

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Response Of Fish Communities To Habitat Alteration In A Small Ozark Stream, Danny J. Ebert, Stephen P. Filipek Jan 1988

Response Of Fish Communities To Habitat Alteration In A Small Ozark Stream, Danny J. Ebert, Stephen P. Filipek

Journal of the Arkansas Academy of Science

From 1984 to 1986, the Arkansas Highway and Transportation Department reconstructed and upgraded a portion of St. Hwy. 123 west of St. Hwy.7 at Pelsor, Arkansas. As a result of the construction, portions of Haw Creek, Johnson County, Arkansas, a third order stream in the Boston Mountains Ecoregion, were straightened and channelized. In reconstructing specific stream reaches, stream banks were riprapped and vegetated, gabions constructed and positioned, stream substrates and pool-riffle ratios altered. Instream and riparian habitat and fish biomass and diversity in altered reaches were radically altered. Channelized reaches became wide and shallow, lacking overstory cover and pools. Substrate …

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Arkansas' Timber Resource: Yesterday, Today, And Tomorrow, Richard A. Kluender, R. L. Willett Jan 1988

Arkansas' Timber Resource: Yesterday, Today, And Tomorrow, Richard A. Kluender, R. L. Willett

Journal of the Arkansas Academy of Science

Demand for forest products continues to rise. Arkansas provides about 4% of the U.S. total forest production and about 12% of the south central region production. Questions exist about the ability of current forest resources to completely meet anticipated future demand. In 1985, the U.S. Forest Service and the Arkansas Timber Study Committee began to analyze the existing forest base to determine whether future demand could be met from the current forest, or if not, what management changes were needed to help meet future demand. In 1985, Arkansas forests covered approximately 48% of the total land area of the state. …

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Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong Jan 1988

Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong

Grain and other field crops research reports

In the past couple of years research into lupins has increased substantially particularly in the fields of weed control, seeding rates, and control of diseases such as brown leaf spot and pleiochaeta root rot. This report is a summary of the lupin trials in the Lake Grace advisory area as well as a guide to better lupin farming.

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Code Lists For Computerized Soil And Land Resource Data Recording, Peter D. King, M R. Wells Jan 1988

Code Lists For Computerized Soil And Land Resource Data Recording, Peter D. King, M R. Wells

Resource management technical reports

No abstract provided.

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Preliminary Groundwater And Salinity Investigations In The Eastern Wheatbelt 2. Merredin Catchment, Richard J. George Dr, P W C Frantom Jan 1988

Preliminary Groundwater And Salinity Investigations In The Eastern Wheatbelt 2. Merredin Catchment, Richard J. George Dr, P W C Frantom

Resource management technical reports

Saline groundwater occurs within twelve metres of the surface throughout the valley of the Merredin catchment. Saline groundwater occurs within deep sediments deposited in the valley and deeply-weathered bedrock materials. Rapid groundwater recharge appears to be taking place in sandy-textured soils high in the landscape and directly into the Cainozoic sediments in the valley floor. Water-tables are rising at approximately ten centimetres each year in the upper catchment area.

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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 …

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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.

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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 …

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