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Managing Brome Grass In The Wheat:Lupin Rotation, Aik Hock Cheam, Gurget Gil, Christine Zaicou Jan 1992

Managing Brome Grass In The Wheat:Lupin Rotation, Aik Hock Cheam, Gurget Gil, Christine Zaicou

Journal of the Department of Agriculture, Western Australia, Series 4

Some farmers and scientists are questioning the sustainability of the cereal:lupin rotation in the Western Australian wheatbelt.

Being a 'tight' rotation, its continuation is constantly under threat by disease, especially lupin root rots caused by Pleiochaeta (the brown spot organism) and Rhizoctonia fungi. To control disease, some farmers have lengthened the rotation to three years, such as wheat:wheat:lupins or wheat:barley:lupins. The longer cereal phase also helps to stabilise soil against wind erosion. However, such rotations can lead to a rapid buildup of brome grass during the two consecutive years of cereals. The implications of these rotations on the severity of …


Recent Improvements Of Water Quality And Biological Indicators In Hillsborough Bay, A Highly Impacted Subdivision Of Tampa Bay, Florida, J.O. R. Johansson, R. R. Lewis Iii Jan 1992

Recent Improvements Of Water Quality And Biological Indicators In Hillsborough Bay, A Highly Impacted Subdivision Of Tampa Bay, Florida, J.O. R. Johansson, R. R. Lewis Iii

Reports

Hillsborough Bay, the eastern uppermost section of the Tampa Bay system, is surrounded by a large metropolitan complex, supports extensive industrial activity, and serves as a major shipping port of fertilizer products. The Bay was determined to be highly eutrophic during the late 1960s. The City of Tampa's primary sewage treatment plant and runoff from fertilizer industry activities were considered as the major sources of excessive nutrient loading. Loadings form both these sources have been reduced during the last 10 years, which has probably been the leading cause of improved water quality parameters such as water clarity, dissolved oxygen, and …


1992 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie Jan 1992

1992 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 1992.


1992 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group Jan 1992

1992 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 1992.


Geology Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii, R. G. Baker Jan 1992

Geology Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii, R. G. Baker

Journal of the Iowa Academy of Science: JIAS

Fens are peatlands which are dependent on groundwater discharge to provide nutrient enrichment. Fens are found in a variety of landscape positions and in most Iowa landform regions. This paper presents a classification system for Iowa fens based on landscape position, stratigraphy, and hydrologic factors. Iowa fens can be separated into six categories: 1) fens along valley wall slopes; the groundwater source for these fens is sand and gravel buried between glacial tills (inter-till); 2) fens in hummocky topography on the northwestern margin of the Des Moines Lobe landform region; the water source is sand and gravel buried within glacial …


The University Of Iowa Museum Of Natural History: An Historical Perspective, George D. Shrimper Jan 1992

The University Of Iowa Museum Of Natural History: An Historical Perspective, George D. Shrimper

Journal of the Iowa Academy of Science: JIAS

The 132-year record of UIMNH essentially mirrors historical and on-going trends in related institutions. As scholarship grew in the natural sciences during the 19th century, natural history museums became centers for scientific research. A "Golden Age" of museum-based expeditionary work and taxonomic research was marked at UI by the careers of curator/naturalists Calvin, Nutting, Macbride, and Shimek. Systematic biology and paleontology thrived with the accumulation of extensive collections. De-emphasis of "natural history" studies followed after 1920-30 with a concomitant growth in cellular and molecular biology. In seeking new directions and financial support, many museums, including UIMNH, shifted emphasis to public …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1992

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Lithium Transport, Mg2+ Competition, And Phospholipid Composition In Human Erythrocytes: A Multinuclear Magnetic Resonance Study, Aida Abraha Jan 1992

Lithium Transport, Mg2+ Competition, And Phospholipid Composition In Human Erythrocytes: A Multinuclear Magnetic Resonance Study, Aida Abraha

Dissertations

No abstract provided.


Spin Label Studies Of Radical Reduction In Normal And Sickle Erythrocyte Membranes Associated With Antioxidants, Yin Zhang Jan 1992

Spin Label Studies Of Radical Reduction In Normal And Sickle Erythrocyte Membranes Associated With Antioxidants, Yin Zhang

Dissertations

No abstract provided.


Multinuclear Magnetic Resonance Study Of Chlorine And Cesium Ion Distribution In Human Erythrocyte Suspensions, Lisa Wittenkeller Jan 1992

Multinuclear Magnetic Resonance Study Of Chlorine And Cesium Ion Distribution In Human Erythrocyte Suspensions, Lisa Wittenkeller

Dissertations

No abstract provided.


The Probe, Issue 118 - January/February 1992 Jan 1992

The Probe, Issue 118 - January/February 1992

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
JANUARY/FEBRUARY 1992
Last Chance for NADCA Membership & Logo Contest!
NRA& Utah State Positions Now Available
NADCA Membership Meeting at Vertebrate Pest Conference


13.2.7. Identifying The Factors That Limit Duck Production, James K. Ringelman Jan 1992

13.2.7. Identifying The Factors That Limit Duck Production, James K. Ringelman

Waterfowl Management Handbook

Low duck populations in the late 1980’s and early 1990’s prompted unprecedented action from the natural resources community. Agencies and private organizations that were traditionally involved with waterfowl management redoubled their efforts, in the process forming partnerships with groups that were relatively new to the waterfowl management arena. Many resource managers who have had relatively little experience with waterfowl habitat management now find themselves expected to manage duck populations for increased production. Decades of waterfowl research and management experience have provided them with many potential management tools. Unfortunately, the absence of general guidelines for directing waterfowl management actions has put …


13.2.14. Management Of Habitat For Breeding And Migrating Shorebirds In The Midwest, Jan Eldridge Jan 1992

13.2.14. Management Of Habitat For Breeding And Migrating Shorebirds In The Midwest, Jan Eldridge

Waterfowl Management Handbook

Shorebirds have always relied on the extensive network of natural wetlands from Texas to North Dakota. This network has now been fractured by wetland drainage and agriculture to the point where suitable wetlands are absent in much of the Midwest. Habitat loss and the resulting risk of population decline highlight the importance of management of shorebirds on refuges, hunting clubs, and preserves for both breeding and migrating species.

Because shorebirds, like waterfowl, depend on wetlands throughout the year, the loss of natural wetlands in the Midwest poses a real threat. Unfortunately, shorebirds are slow to recover from population declines caused …


13.3.6. Ecology Of Montane Wetlands, James K. Ringelman Jan 1992

13.3.6. Ecology Of Montane Wetlands, James K. Ringelman

Waterfowl Management Handbook

Most waterfowl managers envision typical waterfowl habitat as the undulating or flat terrain characteristic of the prairie pothole region of the north-central United States or the aspen parklands of Canada. However, several other habitats in North America provide valuable resources for breeding and migrating waterfowl. Among these is the Rocky Mountain region of the western United States, which stretches in a band 100&#;500 miles (160&#;800 km) wide and 1,240 miles (1,984 km) long from south-central New Mexico to northern Montana (Figure).

Some Rocky Mountain wetland complexes contain waterfowl breeding densities that equal or exceed those of prairie breeding habitat, and …


Checklist Of The Vascular Flora Of Page County, Iowa, Barbara L. Wilson Jan 1992

Checklist Of The Vascular Flora Of Page County, Iowa, Barbara L. Wilson

Journal of the Iowa Academy of Science: JIAS

The vascular flora of Page County, Iowa, was studied from 1987 through 1991. Seven hundred forty two species and four hybrids of vascular plants were found. A quarter of the flora consists of non-native species. Taxa not previously reported in Iowa include: Amsinckia intermedia, Brassica kaber, Cardaria chalapensis, Callirhoe bushii, Carex mesochorea, Eleocharis xyridiformis, Euphorbia prostrata, Lactuca saligna, Leontodon autumnalis, Scirpus mucronatus, Sclerochloa dura, and Vernonia arkansana.


Annual Report Of The Iowa Academy Of Science, 1991-92, Paul E. Rider Jan 1992

Annual Report Of The Iowa Academy Of Science, 1991-92, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

Starting in 1976, annual reports have served as a continuing record of the activities of the Iowa Academy of Science. These augment a 100 year history of the Academy which was written in the centennial year of 1975.

This report covers the period from July 1, 1991 to June 30, 1992. It is based on the official records of the Academy (committee reports, Board minutes, correspondence) as well as the recollections, impressions and thoughts of the author.


Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole Jan 1992

Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole

Watershed Sciences Faculty Publications

Drastic reductions in NO3- leaching have been observed after harvesting of mature red alder (Alnus rubra Bong.) stands. Our objective was to examine whether these reduction were linked to changes in soil N dynamics. Adjacent alder and Douglas fir [Pseudotsuga menziessii (Mirbel.) Franco] stands on young glacial soils (Alderwood; a loamy-skeletal, mixed, mesic, ortstein Aquic Haplorthod) in western Washington were harvested and replanted with either alder or Douglas fir seedlings; reference plots were established in nearby undisturbed stands. Three years after site conversion, when NO3- leaching declined most drastically in the harvested alder plots, net N mineralization and net nitrification …


Visual Feeding By Juvenile Bear Lake Sculpin, D. Neverman, Wayne A. Wurtsbaugh Jan 1992

Visual Feeding By Juvenile Bear Lake Sculpin, D. Neverman, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Young-of-the-year Bear Lake sculpin Cottus extensus feed throughout the day on benthic invertebrates and cease feeding at night when they migrate to the metalimnion. We investigated their reliance on vision by conducting feeding trials at different light levels in the laboratory. Feeding rate reached a maximum at intermediate light levels (near 10^16 photons sm^–2 ss^–1; approximately 1 lux) but decreased as light intensity increased beyond this range. At this maximum rate, the fish fed nine times faster than they were able to feed in the dark, showing that young Bear Lake sculpin rely heavily upon vision to feed. The light …


A Trophic Gradient Analysis Of Lake Powell During Spring Runnoff 1992, Wayne A. Wurtsbaugh, Clyde Lay, Darren Carlise, Corey Huxol, Craig Schaugaard, Beau Clements, David Beauchamp Jan 1992

A Trophic Gradient Analysis Of Lake Powell During Spring Runnoff 1992, Wayne A. Wurtsbaugh, Clyde Lay, Darren Carlise, Corey Huxol, Craig Schaugaard, Beau Clements, David Beauchamp

Watershed Sciences Faculty Publications

Between 26 April and 2 May 1992, students in a utah state university aquatic ecology class visited Lake Powell to do a study of trophic gradients of the reservoir. The main axis of the reservoir was surveyed, as well as less detailed analyses of Moki and Escalante Canyons. The work was conducted in collaboration with personnel from the u.s. Bureau of Reclamation headed by Bill Vernieu, and from the u.s. Geological Survey (Dick Marzolf). Some of their data appear in the physical-chemical section of this report.

Each student was responsible for compiling a report on one of the following specific …


Fifty Years Of Fisheries Management M An Obstinate Prairie Lake, Dennis L. Scarnecchia, James R. Wahl Jan 1992

Fifty Years Of Fisheries Management M An Obstinate Prairie Lake, Dennis L. Scarnecchia, James R. Wahl

Journal of the Iowa Academy of Science: JIAS

Little Wall Lake, a shallow 104 ha glacial lake in Hamilton County, Iowa, has been manipulated for about 50 years by fishery managers in an attempt to provide a stable sport fishery. Managers have used dredging, water level manipulation, aquatic vegetation control, mechanical fish removal and fish eradication with toxicants, sport fish stocking, introduction of piscivorous fish, artificial habitat structures, and winter aeration. Attempts to stabilize the fishery have been unsuccessful, and because of overpopulation and stunting of panfishes, total fish eradications were conducted in 1977 and 1989. We review the history of management efforts on the lake, and suggest …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1992

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Back Cover Jan 1992

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1992

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Back Cover Jan 1992

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


History Of Iowa Natural History - A Symposium, Neil P. Bernstein Jan 1992

History Of Iowa Natural History - A Symposium, Neil P. Bernstein

Journal of the Iowa Academy of Science: JIAS

This issue of the Journal of the Iowa Academy of Science presents the first written installment of our symposium: papers on the contributions of Keyes, Pammel, Bessey, and Hayden; the role of the Iowa Natural History Museum; and histories of both the development of early natural history studies and mammalogy investigations. More papers will follow in future issues, and new contributors are welcome.


History Of Mammal Study In Iowa, John B. Bowles Jan 1992

History Of Mammal Study In Iowa, John B. Bowles

Journal of the Iowa Academy of Science: JIAS

The first records of mammals in Iowa were from explorers, survey parties heading westward and early seeders. Generation of checklists of state mammals began in 1840 and culminated with the annotated list by Scott (1937) and biogeographic analysis by Bowles (1975). Recent focus has been on rare species status and mammalian ecology, e.g., Loess Hills, riparian habitat, agricultural practices, and reestablished grasslands.


Phytoplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson Jan 1992

Phytoplankton Community Abundance And Diversity In Dardanelle Reservoir, Arkansas, 1981-1990, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Phytoplankton samples were collected quarterly from 1981-1990 at five stations representing discharge water from Arkansas Nuclear One, a nuclear generating station, and four "control" or "dispersal evaluation" stations. Seventy-five taxa representing five divisions were identified and enumerated. Community structure was evaluated using abundances, number of taxa, and Margalef's Richness, Shannon's Heterogeneity and Pielou's Evenness indices. No long-term trends were identified, but the beginning of cyclic variations, with a 7-year periodicity, in abundance, number of taxa, and Shannon's and Pielou's indices were apparent. Margalef's index values were constant during most of the study period. For all samples, t-tests and Mann-Whitney U …


Bacteriological Water Quality Of Beaver Reservoir, Arkansas, Jimmy D. Bragg, Mark E. Clark Jan 1992

Bacteriological Water Quality Of Beaver Reservoir, Arkansas, Jimmy D. Bragg, Mark E. Clark

Journal of the Arkansas Academy of Science

Beaver Reservoir water quality was determined through enumeration of Total coliforms and Fecal coliforms bacterial parameters at selected locations during 1991. Several areas of the reservoir contained high numbers of indicator bacteria, suggesting excessive fecal contamination. Significant numbers of salmonella-like bacteria were also cultured on SS agar, and several strains were serotyped positive for Salmonella antigens.


Factors Limiting Overwinter Survival Of Young-Of-The-Year Largemouth Bass In South Dakota, Todd D. Kolander Jan 1992

Factors Limiting Overwinter Survival Of Young-Of-The-Year Largemouth Bass In South Dakota, Todd D. Kolander

Electronic Theses and Dissertations

Studies were conducted to examine the effects of total length (TL), prey abundance, and water temperature on approximate body composition, condition index, and overwinter survival of young-of-the-year (YOY) largemouth bass Micropterus salmoides in South Dakota. Growth and condition of YOY largemouth bass stocks from South Dakota and Wisconsin were also compared. Study areas included two South Dakota University impoundments (0.8 hectare each), a gravel pit (7. 3 hectare), and laboratory aquaria. Hatchery reared YOY largemouth bass were graded into short (19-45 mm TL) and long (58-135 mm TL) length groups. Overwinter mortality was 78% and 85% in the two impoundments, …


Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker Jan 1992

Natural And Technological Disasters: Causes, Effects And Preventive Measures, Nazrul I. Khandaker

Publications and Research

No abstract provided.