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Natural Resource Management Issues For The South Coast Regional Strategy, B Nicholas Jan 2005

Natural Resource Management Issues For The South Coast Regional Strategy, B Nicholas

Resource management technical reports

This report has been prepared by the Agricultural Resource Management Program of the Department of Agriculture to assist SCRIPT (South Coast Regional Initiative Planning Team) in preparing the regional strategy. It records the key natural resource management issues threatening agricultural land on the south coast of Western Australia. Managing agricultural land effectively should be a priority in reducing the risks of land degradation on all assets-productive agricultural land, biodiversity and waterways.


Upper Yilgarn Catchment Appraisal 2005, Keith Ohlsen, Susan Murphy-White Jan 2005

Upper Yilgarn Catchment Appraisal 2005, Keith Ohlsen, Susan Murphy-White

Resource management technical reports

Soil degradation on farmland reduces agricultural production and will often lead to damage to natural resources such as remnant vegetation and waterways, as well as to infrastructure, including roads and townsites. This report provides current information on the land degradation status for the Upper Yilgarn Catchment area in Western Australia by outlining: condition of the soils, hydrology, natural vegetation, farming systems and agricultural production and risks to natural resources.


Reevaluation Of Species Concepts Of Uppermost Cretaceous Unionidae (Mollusca: Bivalvia) : Hell Creek Formation, Montana, U.S.A., Marron J. Bingle Jan 2005

Reevaluation Of Species Concepts Of Uppermost Cretaceous Unionidae (Mollusca: Bivalvia) : Hell Creek Formation, Montana, U.S.A., Marron J. Bingle

Theses and Dissertations

Species are the basic units of life relative to taxonomy, and a practical definition of species is imperative to paleontology in order to promote reproducible, unambiguous criteria for accurately interpreting past species relationships. The need for a well-defined rubric for identifying species is evident in the freshwater mussel assemblage (Family Unionidae) in the Hell Creek Formation. The Hell Creek Formation unionid species were first described by Whitfield in 1903 and 1907. His descriptions were often based on differences of a single trait. In 1976, Russell reevaluated the original species descriptions, I but still based the classification of species on only …


Native Or Introduced? Fossil Pollen And Spores May Say. An Example From The Azores Islands, Jacqueline F.N. Van Leeuwen, Hanno Schäfer, W. O. Van Der Knapp, Tammy M. Rittenour, Svante Björck, Brigitta Ammann Jan 2005

Native Or Introduced? Fossil Pollen And Spores May Say. An Example From The Azores Islands, Jacqueline F.N. Van Leeuwen, Hanno Schäfer, W. O. Van Der Knapp, Tammy M. Rittenour, Svante Björck, Brigitta Ammann

Geosciences Faculty Publications

Aim: Among the various possible approaches to assess whether a species is native or introduced, the analysis of subfossil pollen and spores from natural archives is a valuable tool. Requirements include a sufficiently high taxonomic resolution of the pollen morphology, as well as sufficient temporal and spatial resolution. The aim of this study is to show the usefulness of this method in solving whether the taxon is native or introduced.

Location: The results are derived from two islands of the Azores: Flores and Pico. Methods: Analysis of pollen and spores in lake sediments; radiocarbon dating of the studied sediments.

Results: …


Morphological And Physiological Abnormalities In Tissue Culture-Derived Date Palm (Phoenix Dactylifera L.) Plants, Hamad Saif Al-Mazroui Jan 2005

Morphological And Physiological Abnormalities In Tissue Culture-Derived Date Palm (Phoenix Dactylifera L.) Plants, Hamad Saif Al-Mazroui

Theses

The UAE attaches great importance to agricultural development with a sound focus on date palms. This special attention is obvious in the ongoing expansion of agricultural resources and investments, the growing number of palm trees, and in the extensive use of modern technologies. Mass cultivation of date palm trees is required to continue according to the country's agricultural plans.

In order to achieve these agricultural expansion of date palm, new techniques of propagation other than traditional techniques (seed and offshoot propagation) are critically required. Tissue culture is a modern and reliable technology being one of the main methods for date …


Calcareous Nannoplankton Response To Late Albian Oceanic Anoxic Event 1d In The Western North Atlantic, David K. Watkins, Matthew J. Cooper, Paul A. Wilson Jan 2005

Calcareous Nannoplankton Response To Late Albian Oceanic Anoxic Event 1d In The Western North Atlantic, David K. Watkins, Matthew J. Cooper, Paul A. Wilson

Department of Earth and Atmospheric Sciences: Faculty Publications

Well-preserved nannofossil and stable isotope records from the mid-Cretaceous of Ocean Drilling Project Leg 171B (western North Atlantic) indicate cyclical, productivity-based variations in surface water characteristics, suggesting orbitally paced changes in upwelling intensity and the strength of deep mixing associated with oceanic anoxic event (OAE)1d. Paleontologic and isotopic evidence suggest that collapse of upper water column stratification associated with OAE1d was preceded by approximately 1 m.y. of progressively decreasing water column stability and increasing surface water fertility. Thirteen species went extinct during a short (ca. 200 k.y.) interval associated with OAE1d. Nine of these have morphological characters suggesting adaptation to …


Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia Jan 2005

Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia

Animal production and livestock published reports

Food On Offer (FOO) is the amount of pasture in front of an animal, and is measured in kilograms Dry Matter per hectare. Managing pastures to key grazing levels - or FOO targets - can result in improved production of grazing systems in Mediterranean environments which are characterized by slow winter growth, peak spring growth and dry summers. These targets vary according to what production response is required.

This information sheet illustrates key target FOO for sheep grazing annual pastures during autumn and spring.


High-Resolution Ocean Color Remote Sensing Of Benthic Habitats: A Case Study At The Roatan Island, Honduras, Deepak R. Mishra, Sunil G. Narumalani, Donald Rundquist, Merlin P. Lawson Jan 2005

High-Resolution Ocean Color Remote Sensing Of Benthic Habitats: A Case Study At The Roatan Island, Honduras, Deepak R. Mishra, Sunil G. Narumalani, Donald Rundquist, Merlin P. Lawson

Department of Earth and Atmospheric Sciences: Faculty Publications

Natural resource managers clamor for detailed reef habitat maps for monitoring smaller scale disturbances in reef communities. Coastal ocean color remote sensing techniques permit benthic habitats to be explored with higher resolution than ever before. The objective of this research was to develop an accurate benthic habitat map for an area off the northwest coast of Roatan Island, Honduras, using high-resolution multispectral IKONOS data. Atmospheric (Rayleigh and aerosol path radiance) and water column corrections (water depth and water column attenuation) were applied to the imagery, making it a robust method for mapping benthic habitats. Water depth for each pixel was …


A Multilocus Population Genetic Survey Of The Greater Sage-Grouse Across Their Range, S. J. Oyler-Mccance, S.E. Taylor, T. W. Quinn Jan 2005

A Multilocus Population Genetic Survey Of The Greater Sage-Grouse Across Their Range, S. J. Oyler-Mccance, S.E. Taylor, T. W. Quinn

United States Geological Survey: Staff Publications

The distribution and abundance of the greater sage-grouse (Centrocercus urophasianus) have declined dramatically, and as a result the species has become the focus of conservation efforts. We conducted a range-wide genetic survey of the species which included 46 populations and over 1000 individuals using both mitochondria1 sequence data and data from seven nuclear microsatellites. Nested clade and STRUCTURE analyses revealed that, in general, the greater sage-grouse populations follow an isolation-by-distance model of restricted gene flow. This suggests that movements of the greater sage-grouse are typically among neighboring populations and not across the species, range. This may have important …


Transport Of Chemical And Microbial Compounds From Known Wastewater Discharges: Potential For Use As Indicators Of Human Fecal Contamination, Susan Glassmeyer, Edward Furlong, Dana Kolpin, Jeffrey Cahill, Steven Zaugg, Stephen Werner, Michael Meyer, David Kryak Jan 2005

Transport Of Chemical And Microbial Compounds From Known Wastewater Discharges: Potential For Use As Indicators Of Human Fecal Contamination, Susan Glassmeyer, Edward Furlong, Dana Kolpin, Jeffrey Cahill, Steven Zaugg, Stephen Werner, Michael Meyer, David Kryak

United States Geological Survey: Staff Publications

The quality of drinking and recreational water is currently (2005) determined using indicator bacteria. However, the culture tests used to analyze for these bacteria require a long time to complete and do not discriminate between human and animal fecal material sources. One complementary approach is to use chemicals found in human wastewater, which would have the advantages of (1) potentially shorter analysis times than the bacterial culture tests and (2) being selected for human-source specificity. At 10 locations, water samples were collected upstream and at two successive points downstream from a waste-waster treatment plant (WWTP); a treated effluent sample was …


Climate Change And Amphibians, P.S. Corn Jan 2005

Climate Change And Amphibians, P.S. Corn

United States Geological Survey: Staff Publications

Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated mortality of amphibian embryos in the northwestern United States. However, evidence linking amphibian declines in Central America to climate relies solely on correlations, and the mechanisms underlying the declines are not understood. Connections between embryo mortality and declines …


An Evaluation Of Weather And Disease As Causes Of Decline In Two Populations Of Boreal Toads, Rick D. Scherer, Erin Muths, Barry R. Noon, Paul Stephen Corn Jan 2005

An Evaluation Of Weather And Disease As Causes Of Decline In Two Populations Of Boreal Toads, Rick D. Scherer, Erin Muths, Barry R. Noon, Paul Stephen Corn

United States Geological Survey: Staff Publications

Two populations of boreal toads (Bufo boreas) experienced drastic declines in abundance in the late 1990s. Evidence supported the hypothesis of disease (the chytrid fungus, Batrachochytrium dendrobatidis) as the cause of these declines. but other hypotheses had not been evaluated. We used an 11-year capture-recapture data set to evaluate weather and disease as causes of these declines. We developed sets of mathematical models that reflected hypothesized relationships between several weather variables and annual survival rates of adult males in these populations. In addition, models that reflected the possibility that the declines were caused by an introduced fungus …


Amphibian Research And Monitoring Initiative (Armi): A Successful Start To A National Program In The United States, Erin Muths, Robin E. Jung, Larissa L. Bailey, Michael J. Adams, P. Stephen Corn, C. Kenneth Dodd Jr., Gary M. Fellers, Walter J. Sadinski, Cecil R. Schwalbe, Susan C. Walls, Robert N. Fisher, Alisa L. Gallant, William A. Battaglin, D. Earl Green Jan 2005

Amphibian Research And Monitoring Initiative (Armi): A Successful Start To A National Program In The United States, Erin Muths, Robin E. Jung, Larissa L. Bailey, Michael J. Adams, P. Stephen Corn, C. Kenneth Dodd Jr., Gary M. Fellers, Walter J. Sadinski, Cecil R. Schwalbe, Susan C. Walls, Robert N. Fisher, Alisa L. Gallant, William A. Battaglin, D. Earl Green

United States Geological Survey: Staff Publications

Most research to assess amphibian declines has focused on local-scale projects on one or a few species. The Amphibian Research and Monitoring Initiative (ARMI) is a national program in the United States mandated by congressional directive and implemented by the U.S. Department of the Interior (specifically the U.S. Geological Survey, USGS). Program goals are to monitor changes in populations of amphibians across U.S. Department of the Interior lands and to address research questions related to amphibian declines using a hierarchical framework of base-, mid- and apex-level monitoring sites. ARMI is currently monitoring 83 amphibian species (29% of species in the …


Participant Observations On Environmental And Social Eff Ect S Of The Conservation Reserve Program: Results Of A National Survey, Arthur W. Alen Jan 2005

Participant Observations On Environmental And Social Eff Ect S Of The Conservation Reserve Program: Results Of A National Survey, Arthur W. Alen

United States Geological Survey: Staff Publications

A national survey of Conservation Reserve Program (CRP) contractees was completed to obtain information about environmental and social effects of the program on participants, farms, and communities. Over 75% of respondents believed CRP benefits to wildlife were important. Seventy-three percent of respondents observed increased numbers of wildlife associated with CRP lands. A majority of respondents (82%) believed the amount of assistance furnished by the U.S. Department of Agriculture related to planning and maintaining wildlife habitat associated with CRP lands was appropriate. The majority of respondents reported CRP benefits, including increased quality of surface and ground waters, improved air quality, control …


Geochemistry Of Sulfate Minerals In High- And Low-Temperature Environments: A Tribute To Robert O. Rye, Robert R. Seal Ii, John L. Jambor, Charles N. Alpers Jan 2005

Geochemistry Of Sulfate Minerals In High- And Low-Temperature Environments: A Tribute To Robert O. Rye, Robert R. Seal Ii, John L. Jambor, Charles N. Alpers

United States Geological Survey: Staff Publications

This special issue is a tribute to Robert O. Rye, known as "Bob" to most, in light of his highly productive and ongoing career. Almost all of the papers in this issue are derived from topical sessions on sulfate minerals in hydrothermal and low-temperature environments. The sessions, held at the 2000 Geological Society of America meeting in Reno, NV, and sponsored jointly by the Mineralogical Society of America, the Society of Economic Geologists and the Geochemical Society, included 29 oral and 9 poster presentations. The sessions complemented a short course on the crystallography, geochemistry and environmental significance of sulfate minerals, …


Comparison Of A Novel Passive Sampler To Standard Water-Column Sampling For Organic Contaminants Associated With Wastewater Effluents Entering A New Jersey Stream, D. A. Alvarez, P. E. Stackelberg, J. D. Petty, J. N. Huckins, E. T. Furlong, S. D. Zaugg, M. T. Meyer Jan 2005

Comparison Of A Novel Passive Sampler To Standard Water-Column Sampling For Organic Contaminants Associated With Wastewater Effluents Entering A New Jersey Stream, D. A. Alvarez, P. E. Stackelberg, J. D. Petty, J. N. Huckins, E. T. Furlong, S. D. Zaugg, M. T. Meyer

United States Geological Survey: Staff Publications

Four water samples collected using standard depth and width water-column sampling methodology were compared to an innovative passive, in situ, sampler (the polar organic chemical integrative sampler or POCIS) for the detection of 96 organic wastewater-related contaminants (OWCs) in a stream that receives agricultural, municipal, and industrial wastewaters. Thirty-two OWCs were identified in POCIS extracts whereas 9–24 were identified in individual water-column samples demonstrating the utility of POCIS for identifying contaminants whose occurrence are transient or whose concentrations are below routine analytical detection limits. Overall, 10 OWCs were identified exclusively in the POCIS extracts and only six solely identified in …


Selenium Impactson Razorback Sucker, Colorado River, Colorado I. Adults, Steven J. Hamilton, Kathy M. Holley, Kevin J. Buhl, Fern A. Bullard, L. Ken Weston, Susan F. Mcdonald Jan 2005

Selenium Impactson Razorback Sucker, Colorado River, Colorado I. Adults, Steven J. Hamilton, Kathy M. Holley, Kevin J. Buhl, Fern A. Bullard, L. Ken Weston, Susan F. Mcdonald

United States Geological Survey: Staff Publications

Adult razorback sucker (Xyrauchen texanus) were exposed to various selenium concentrations in ponds and isolated river channels of the Colorado River near Grand Junction, CO, to determine effectson their growth and residue accumulation over an 11-month period. Adults at Horsethief ponds were fed a commercial diet, whereas fish at Adobe Creek channel and North Pond foraged on natural food items. Selenium concentrations at Horsethief were 2.2 μg/L in water, 0.1–1.4 μg/g in sediment, and 2.3–3.1 μg/g in food organisms (1.1 μg/g in commercial fish food), at Adobe Creek were 3.8 μg/L in water, 0.5–2.1 μg/g in sediment, and …


Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhall, Charles N. Alpers, Gregg A. Swayze Jan 2005

Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhall, Charles N. Alpers, Gregg A. Swayze

United States Geological Survey: Staff Publications

Prior to remediation at the abandoned Cu–Zn Penn Mine in the Foothills massive sulfide belt of the Sierra Nevada, CA, acid mine drainage (AMD) was created, in part, by the subaerial oxidation of sulfides exposed on several waste piles. To support remediation efforts, a mineralogical study of the waste piles was undertaken by acquiring reflectance spectra (measured in the visible to short-wave infrared range of light (0.35–2.5 Am) using a portable, digitally integrated pen tablet PC mapping system with differential global positioning system and laser rangefinder support. Analysis of the spectral data made use of a continuum removal and band-shape …


High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf Jan 2005

High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf

United States Geological Survey: Staff Publications

Global losses of amphibian populations are a major conservation concern and have generated substantial debate over their causes. Habitat fragmentation is considered one important cause of amphibian decline. However, if fragmentation is to be invoked as a mechanism of amphibian decline, it must first be established that dispersal is prevalent among contiguous amphibian populations using formal movement estimators. In contrast, if dispersal is naturally low in amphibians, fragmentation can be disregarded as a cause of amphibian declines and conservation efforts can be focused elsewhere. We examined dispersal rates in Columbia spotted frogs (Rana luteiventris) using capture– recapture analysis …


Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf Jan 2005

Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf

United States Geological Survey: Staff Publications

Landscape features such as mountains, rivers, and ecological gradients may strongly affect patterns of dispersal and gene flow among populations and thereby shape population dynamics and evolutionary trajectories. The landscape may have a particularly strong effect on patterns of dispersal and gene flow in amphibians because amphibians are thought to have poor dispersal abilities. We examined genetic variation at six microsatellite loci in Columbia spotted frogs (Rana luteiventris) from 28 breeding ponds in western Montana and Idaho, USA, in order to investigate the effects of landscape structure on patterns of gene flow. We were particularly interested in addressing …


2005- 2008 Unlv Mcnair Journal, Valerie Avery, Shana Bachus, Karmen K. Boehlke, Andrea Flores, Alden Kelly, Erick Lopez, Carol Preussler, Heather Shay, Ava Bookatz, Shaun Elsasser, Veronica Hicks, Shaida A. Jetha, Anthony Quinn, Thurithabhani Seneviratne, Teddy Boado Sim Jr., Liza Ward, Amris Henry-Rodgers, Jacquelynn Kaaa-Logan, Jason Orozco, Juan C. Plata, Bonnie Bartlett, Kathleen Bell, Vacheral M. Carter, Nydia Diaz, Kimberly Hackstock, Julio A. Luna, Charles Mao, Sandra Ramos, Precious Rideout, Benjamin Lee Watrous, Chet R. Whitley Jan 2005

2005- 2008 Unlv Mcnair Journal, Valerie Avery, Shana Bachus, Karmen K. Boehlke, Andrea Flores, Alden Kelly, Erick Lopez, Carol Preussler, Heather Shay, Ava Bookatz, Shaun Elsasser, Veronica Hicks, Shaida A. Jetha, Anthony Quinn, Thurithabhani Seneviratne, Teddy Boado Sim Jr., Liza Ward, Amris Henry-Rodgers, Jacquelynn Kaaa-Logan, Jason Orozco, Juan C. Plata, Bonnie Bartlett, Kathleen Bell, Vacheral M. Carter, Nydia Diaz, Kimberly Hackstock, Julio A. Luna, Charles Mao, Sandra Ramos, Precious Rideout, Benjamin Lee Watrous, Chet R. Whitley

McNair Journal

Journal articles based on research conducted by undergraduate students in the McNair Scholars Program

Table of Contents

Biography of Dr. Ronald E. McNair

Statements:

Dr. Neal J. Smatresk, UNLV President

Dr. Juanita P. Fain, Vice President of Student Affairs

Dr. William W. Sullivan, Associate Vice President for Retention and Outreach

Mr. Keith Rogers, Deputy Executive Director of the Center for Academic Enrichment and Outreach

McNair Scholars Institute Staff


Agricultural Pollution Of Ground Water Near Gilbertville, Iowa, Paula Frost Even Jan 2005

Agricultural Pollution Of Ground Water Near Gilbertville, Iowa, Paula Frost Even

Dissertations and Theses @ UNI

The transport of nutrients and contaminants from farm fields to the aquifer surrounding Gilbertville, Iowa, was monitored over a six-month period. The Gilbertville city water supply is obtained from the Silurian-Devonian aquifer, which has been determined to be highly susceptible to contamination because of the hydraulic characteristics of the aquifer and the overlying materials that allow contaminants to move to the aquifer fairly quickly. Monthly water samples were collected from April through September of 2004 from 26 private wells and 8 surface water sites within the source water protection area of the town's three wells. Each sample was tested for …


The Role Of Geomorphic Features And Hydrologic Processes On Sediment Clusters In Gravel-Bed Rivers, Washington: A Field-Based Approach, Ross Richard Hendrick Jan 2005

The Role Of Geomorphic Features And Hydrologic Processes On Sediment Clusters In Gravel-Bed Rivers, Washington: A Field-Based Approach, Ross Richard Hendrick

All Master's Theses

This project investigated the movement and evolution of sediment clusters after four separate flood events at two geomorphically different sites along the Entiat River, Washington. Clusters are defined as an obstacle or anchor clast(s) that impede the progress of two or more sediment particles, and are believed to be an important characteristic of the variable bed topography of gravel-bed rivers. Detailed field descriptions and digital photographs of clusters were used to determine the characteristics of clusters at chosen locations on gravel bars regularly covered by high flow events. Data were collected during low-flow conditions, and clusters were re- examined and …


A Salt On The Land: The Osmolyte Production And Physiological Responses Of Selected Myrtaceae Species Exposed To Salt And Water Stress, Janelle Atkinson Jan 2005

A Salt On The Land: The Osmolyte Production And Physiological Responses Of Selected Myrtaceae Species Exposed To Salt And Water Stress, Janelle Atkinson

Theses: Doctorates and Masters

Glasshouse trials were conducted on Calothamnus quadrifidus, Eucalyptus camaldulensis and Melaleuca uncinata

to test relative tolerance and uniformity of response in the Myrtaceae family to salt, waterlogging and salt x waterlogging. Seed sources from both saline (SA) and non-saline areas were used to compare differences in survival, growth and proline production to these stresses.


Carbonate Records Of Submarine Hydrocarbon Venting: Northern Gulf Of Mexico, Matthew S. Hackworth Jan 2005

Carbonate Records Of Submarine Hydrocarbon Venting: Northern Gulf Of Mexico, Matthew S. Hackworth

LSU Doctoral Dissertations

Hydrocarbon seep sediments are examined from 3 sites in the Gulf of Mexico (Green Canyon Lease Blocks 232, 185, and 272) to relate the effects of gas hydrates and hydrocarbons on microbial process, pore fluid chemistry, and the processes of authigenic carbonate formation. Hydrocarbon-fueled microbial reactions result in pore fluids with lowered SO42- (all consumed by –10 cm) and enrichments in H2S, alkalinity, and DIC (up to 20 mmol, 30 meq/L, and 18 mmol/L, respectively) which promote carbonate formation. Pore fluid d13CDIC (PDB) is influenced by thermogenic hydrocarbons and crude oil in GC …


Zooplankton Communities Of Selected Stations Of Lake Victoria, Rk Waya, Ja Mwambungu Dec 2004

Zooplankton Communities Of Selected Stations Of Lake Victoria, Rk Waya, Ja Mwambungu

Tanzania Journal of Science

Species composition and diversity of zooplankton communities of Lake Victoria (Tanzanian waters) were studied. In the shallow waters zooplankton were collected between March and April, and between August and December 2000. In deeper waters zooplankton were collected in August 2001. Overall, 20 genera and 29 species of zooplankton were observed in the shallow waters whereas 12 genera and 20 species of zooplankton were encountered in the deeper waters. The highest abundance was recorded in the deeper waters (2,481,633-2). In the shallow waters the cyclopoid copepods dominated the zooplankton community, the common species being Thermocyclops emini and Thermocyclops neglectus. In the …


Contamination Of Water And Sediments By Obsolete Pesticides At Vikuge Farm, Kibaha Distric, Tanzania, M J Mihale, M A Kishimba Dec 2004

Contamination Of Water And Sediments By Obsolete Pesticides At Vikuge Farm, Kibaha Distric, Tanzania, M J Mihale, M A Kishimba

Tanzania Journal of Science

Sediments and water from Vikuge State Farm, Coast Region, Tanzania, where, in 1986, a “donation” of 170 m3 of partially expired pesticides were stored in an open shed- which eventually collapsed, were analysed for 80 different pesticide residues and metabolites. DDT and HCH, two of the most persistent organochlorines pesticides, were the most dominant pesticides found in both matrices. In sediments the levels were up to 99,620 mg/kg dry weight of ΣDDT and up to 7,400 mg/kg dry weight of ΣHCH. The mean total HCH concentrations were 0.95 μg/l in tap water, 0.28 mg/l in surface water and 3.09 μg/l …


Parasites Of Clarias Gariepinus (Burchell, 1822) (Pisces: Clariidae) From The Mwanza Gulf, Lake Victoria, C Mwita, G Nkwengulila Dec 2004

Parasites Of Clarias Gariepinus (Burchell, 1822) (Pisces: Clariidae) From The Mwanza Gulf, Lake Victoria, C Mwita, G Nkwengulila

Tanzania Journal of Science

Seventeen species of parasites were recovered from 1071 Clarias gariepinus examined from the Mwanza Gulf of Lake Victoria. The parasite fauna comprised of four ectoparasites, a Monogenea, Hirudinea, crustacean and a Digenea; and fourteen endoparasites, five nematodes, five trematodes and three cestodes. Twelve parasite species were adults and five were larval forms. Ten were identified to species, six to genus and one to family level. Many species recorded are common to C. gariepinus, a few, e.g. Tylodelphys species is a first record in fish of Africa, thus represents a new host record. Spinitectus petterae is reported for the first time …


Diurnal Feeding Patterns And Food Habits Of Lates Niloticus In The Speke Gulf, Lake Victoria, Ha Mhitu, Ai Chande Dec 2004

Diurnal Feeding Patterns And Food Habits Of Lates Niloticus In The Speke Gulf, Lake Victoria, Ha Mhitu, Ai Chande

Tanzania Journal of Science

Twenty four hour sampling sessions were conducted to investigate the feeding patterns and food habits of Lates niloticus in the Speke Gulf, Lake Victoria during January/February, July/August and December 2002. Feeding activity was more pronounced during daytime mostly in morning hours than during the night. The most dominant food item was haplochromines. There was a significant difference in the occurrence of food items in the gut of L. niloticus with time. However, there was no significant difference in the occurrence of food items in the habitat at different times. The study concludes with a recommendation for fishermen to set their …


Total Mercury Concentration In Common Fish Species Of Lake Victoria, Tanzania, J F Machiwa Dec 2004

Total Mercury Concentration In Common Fish Species Of Lake Victoria, Tanzania, J F Machiwa

Tanzania Journal of Science

Total mercury (THg) concentration was analysed in muscles of common fish species of Lake Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption Spectrophotometric technique. Mercury concentration in all fish species was generally lower than the WHO maximum allowable concentration (500 ng/g ww) in edible fish parts. The maximum concentration of THg in Lates niloticus samples was 396 ng/g ww. Samples of Oreochromis niloticus had THg concentration ranging between <0.01 and 419 ng/g ww. Clarias gariepinus had THg concentration ranging between 1.2 and 239.1 ng/g ww. All less common fish species, such as, Labeo victirianus, Synodontis victoriae, Oreochromis leucostictus, Schilbe intermedius, Brycinus jacksonii, B. sadleri, Tilapia rendalii, Tilapia zilii and Haplochromines had THg concentration below the WHO maximum allowable limit (500 ng/g ww). The study showed that Hg from small-scale gold mining activities in Lake Victoria basin is not transported to the lake by fluvial discharge. Other possible pathways of Hg input to Lake Victoria are discussed.