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A Two Year Evaluation Of Nitrate-N And Triazine Herbicides In Groundwater And Surface Water Of An Intensively Row Cropped Agricultural Watershed In Western Kentucky, Larry Reber, John Potts Jan 1998

A Two Year Evaluation Of Nitrate-N And Triazine Herbicides In Groundwater And Surface Water Of An Intensively Row Cropped Agricultural Watershed In Western Kentucky, Larry Reber, John Potts

Soil Science News and Views

The quality of water in Kentucky's agricultural watersheds has received considerable attention in recent years. The main concerns in corn production areas usually center on water content of nitrate-N from commercial fertilizer and triazines from herbicide applications. Although N can be found naturally in Kentucky soils, it cannot supply all the N that corn needs to produce optimum yields. Therefore, fertilizer N is added to ensure ample nutrition. Triazines, on the other hand, do not occur naturally in the soil but are applied to the soil to effectively control weeds. Most commonly, these herbicides are applied at the time of …


Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia Jan 1998

Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Recent yield responses by canola where lime has been applied to acidic soils are very encouraging. Two sites have shown that the yield increase in canola after lime was applied in the previous year would have easily paid for the total cost of purchase, transport and application of the lime.

This work was carried out to demonstrate the increased options that are likely to be available once producers are treating or managing soil acidity. Canola is becoming increasingly important as a cash value crop and a break crop allowing wider rotations.

Growers are pushing the limits of canola’s tolerance to …


Managing Seedling Emergence Of Cuphea In Iowa, W. W. Roath Jan 1998

Managing Seedling Emergence Of Cuphea In Iowa, W. W. Roath

Journal of the Iowa Academy of Science: JIAS

Cuphea, a western hemisphere genus of some 260 species, has been proposed as a domestic source of medium-chain fatty acids. These fatty acids are used primarily in soap and detergent manufacture and are presently extracted from imported tropical oils or from petroleum. Considerable difficulty in obtaining consistent plant stands with direct seeding has been experienced at two Iowa locations. Trials were initiated in 1987 and continued through 1994 to test various treatments upon seedling emergence of C. laminuligera Koehne, C lanceolata Ait., and hybrid C. viscosissima Jacq. X C. lanceolata. These treatments included planting depths from 1.3 to 6.4 cm, …


A Teacher's Guide And Study Kit On The Santa Rosa Plateau Ecological Reserve For Middle School Students, Katharine Marie Havert Jan 1998

A Teacher's Guide And Study Kit On The Santa Rosa Plateau Ecological Reserve For Middle School Students, Katharine Marie Havert

Theses Digitization Project

No abstract provided.


Ai And The Changing Face Of Health Care, Erika Rogers Jan 1998

Ai And The Changing Face Of Health Care, Erika Rogers

Computer Science and Software Engineering

No abstract provided.


Environmental Science Curriculum For Eleventh Through Twelfth Grade Classes, Jenelle Sue Bryan Jan 1998

Environmental Science Curriculum For Eleventh Through Twelfth Grade Classes, Jenelle Sue Bryan

Theses Digitization Project

No abstract provided.


Endangered And Threatened Animals Of Utah, Terry Messmer, Marilet Zablan, Boyde Blackwell, Athena Menses, Frank Howe, Leo Lentsch, Richard Drake Jan 1998

Endangered And Threatened Animals Of Utah, Terry Messmer, Marilet Zablan, Boyde Blackwell, Athena Menses, Frank Howe, Leo Lentsch, Richard Drake

All Archived Publications

No abstract provided.


Stable Isotope Analyses Of Tooth Annuli Reveal Temporal Dietary Records: An Example Using Stellar Sea Lions, Keith Hobson, John Sease Jan 1998

Stable Isotope Analyses Of Tooth Annuli Reveal Temporal Dietary Records: An Example Using Stellar Sea Lions, Keith Hobson, John Sease

United States Department of Commerce: Staff Publications

Stable isotope analysis of teeth of marine mammals can provide valuable information on trophic level and source of feeding. However, the isotopic analysis of whole teeth presents only an average dietary estimate for individuals across the period of growth of that tooth. While such analyses can be valuable, particularly in the case of fossil material, in contrast, isotopic analysis of individual annuli of teeth can provide dietary information for each year of tooth growth, in some cases representing the whole of the animal's life. We measured stable-carbon isotope ratios (13C/12C) in the inorganic (hydroxyapatire) and stable-nitrogen …


The Use Of Red Mud/Gypsum To Reduce Water Pollution From Sandy Soils Used For Vegetable Production, Ian Mcpharlin, W. J. Robertson, R. C. Jeffery Jan 1998

The Use Of Red Mud/Gypsum To Reduce Water Pollution From Sandy Soils Used For Vegetable Production, Ian Mcpharlin, W. J. Robertson, R. C. Jeffery

Research Reports

An important domestic and export vegetable industry is located on the sands of the Swan Coastal Plain (SCP) in Western Australia. The total value of the vegetable industry on the SCP was estimated at $90M in 1996/7 or about 50% of the total value of the industry. This vegetable production has been located on good quality sands such as the Spearwood and yellow Karrakatta sands, close to the coast, since the 1950s. However in recent years competition for this land for urban and industrial use has forced vegetable production onto soils with poorer water and phosphorus retention capacity such as …


Linking People, Purpose, And Place: An Ecological Approach To Agriculture, Heidi Carter, Richard Olson, Charles A. Francis Jan 1998

Linking People, Purpose, And Place: An Ecological Approach To Agriculture, Heidi Carter, Richard Olson, Charles A. Francis

CARI Extension and Education Materials for Sustainable Agriculture

Linking Ecology and Agriculture

Whole Farm Planning

Soil Quality

Agroforestry

Grazing Systems

Weed and Insect Management

Farmer Groups

Farmland Conversion

Resources and Information Sources


Porcupine Damage And Repellent Research In The Interior Pacific Northwest, Gary W. Witmer, Michael J. Pipas Jan 1998

Porcupine Damage And Repellent Research In The Interior Pacific Northwest, Gary W. Witmer, Michael J. Pipas

Vertebrate Pest Conference Proceedings: 18th (1998)

Porcupines (Erethizon dorsatum) rely on trees and shrubs for winter food and can cause serious, localized damage to conifers. Twenty-two percent of ponderosa trees (Pinus ponderosa) examined in southeastern Washington were damaged by porcupines. Most damage involved complete girdling of the mid- to upper boles of the larger trees (12 to 30 cm dbh) in the stand. Preliminary repellent trials with captive porcupines suggested that several materials might reduce tree damage, especially predator-associated odors. Field trials are needed to assess efficacy and duration of protection under ambient winter conditions.


Rat Management For Endangered Species Protection In The U.S. Virgin Islands, Gary W. Witmer, Earl W. Campbell Iii, Frank Boyd Jan 1998

Rat Management For Endangered Species Protection In The U.S. Virgin Islands, Gary W. Witmer, Earl W. Campbell Iii, Frank Boyd

Vertebrate Pest Conference Proceedings: 18th (1998)

Introduced roof rats (Rartus rattus) pose a substantial threat to the fauna and flora of many tropical islands. In the Caribbean, there is concern about rat impacts to several endangered species, including the Atlantic hawksbill sea turtle (Eretmochelys imbricata) and the least tern (Sterna antillarum). The authors surveyed the rat population on Buck Island, Buck Island Reef National Monument, U .S. Virgin Islands in February 1998. Based on three nights of trapping, rats were of low to moderate abundance during the sampling period when compared to results from other Caribbean islands. The impact of …


Tracing The History Of Blackbird Research Through An Industry's Looking Glass: The Sunflower Magazine, George M. Linz, H. Jeffrey Homan Jan 1998

Tracing The History Of Blackbird Research Through An Industry's Looking Glass: The Sunflower Magazine, George M. Linz, H. Jeffrey Homan

Vertebrate Pest Conference Proceedings: 18th (1998)

The Sunflower magazine, the voice of the National Sunflower Organization, featured articles in January 1978 and December 1996 that began with these words, "If Old King Cole was a merry old soul, it was probably because he had only four and twenty blackbirds to contend with, and they were all out of commission!" This quotation captures the sentiments of sunflower growers, who have identified blackbirds as a major production problem since the 1960s. The National (formerly Denver) Wildlife Research Center, a unit within the U.S. Department of Agriculture's Animal and Plant Health Inspection Service Wildlife Services, is charged with both …


The Impact Of Timber Management On The Phytochemicals Associated With Black Bear Damage, Dale L. Nolte, Bruce A. Kimball, Georg J. Ziegltrum Jan 1998

The Impact Of Timber Management On The Phytochemicals Associated With Black Bear Damage, Dale L. Nolte, Bruce A. Kimball, Georg J. Ziegltrum

Vertebrate Pest Conference Proceedings: 18th (1998)

Black bears forage on Douglas-fir vascular tissue in the spring, and this behavior can be severely detrimental to the health and economic value of a timber stand. Foraging is selective in that not all stands are damaged and, within a stand, one tree may be stripped while its neighbor is ignored or minimally sampled. A series of studies was conducted to assess whether bear selectivity is affected by chemical constituents within vascular tissue, and whether these constituents are affected by silvicultural practices. The results are interpreted to identify forest practices that may alleviate damage, or at least predict where damage …


Effects Of Taste Stimuli (Quinine And Sucrose) In Pelleted Granulated, And Wax Block Baits On Feeding Preferences Of Northern Pocket Gophers (Thomomys Talpoides), Stephen A. Schumake, Geraldine R. Mccann Jan 1998

Effects Of Taste Stimuli (Quinine And Sucrose) In Pelleted Granulated, And Wax Block Baits On Feeding Preferences Of Northern Pocket Gophers (Thomomys Talpoides), Stephen A. Schumake, Geraldine R. Mccann

Vertebrate Pest Conference Proceedings: 18th (1998)

A two-choice, taste preference study was conducted using 18 northern pocket gophers to evaluate pelleted sorghum, granulated sorghum, and wax block baits containing either 0.01 to 0.05 % quinine or 0.10 to 5.0 % sucrose. Bait consumption was significantly higher across treatments (P≤.001) for granulated sorghum, followed by pelleted sorghum, and wax blocks. Gophers also showed a high frequency of moving the granulated bait in their cheek pouches to be deposited at alternate locations within their cages. Although increasing sucrose concentration did not produce significantly (P ≥.10) enhanced consumption for any of the baits, a trend toward increasing preference with …


Fall 1998, Nsu Oceanographic Center Jan 1998

Fall 1998, Nsu Oceanographic Center

Currents

No abstract provided.


The Occurrence Of Pcbs And Chlorinated Pesticide Contaminants In Bottlenose Dolphins (Tursiops Truncatus) In A Resident Community: Comparison With Age, Gender And Birth Order, Kathleen M. Kuss Jan 1998

The Occurrence Of Pcbs And Chlorinated Pesticide Contaminants In Bottlenose Dolphins (Tursiops Truncatus) In A Resident Community: Comparison With Age, Gender And Birth Order, Kathleen M. Kuss

HCNSO Student Theses and Dissertations

Tissue samples from twenty bottlenose dolphins from a stable, residential community of coastal dolphins in the western Gulf of Mexico were analyzed for toxic PCB congeners and chlorinated pesticides. The tissues analyzed (blubber and melon) were from known individuals in a long-term (27+ y) study that stranded and were recovered for necropsy. Substantial demographic data were available on these individuals and utilized in the analysis of maternal transfer of organochlorines to young.

The male dolphins in this study were shown to accumulate organochlorine contaminants with age. In female dolphins the organochlorine levels were found to decline with age. These …


The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon Jan 1998

The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon

Theses : Honours

Industrial activities and natural occurrences of mineral ores can both result in the presence of high concentrations of heavy metals in the soil. These toxic metals have been shown to adversely affect human health and the environment. Currently, three main technologies are being used to solve this problem of soil contamination. These are incineration, landfill construction and physico-chemical treatments. The economic and environmental costs of each of these technologies tend to outweigh the merits of their application, especially where contaminated areas are small. These techniques do not necessarily remove the heavy metals from the soil, and can also inhibit biological …


Variability In Copepod Hatching Success: Observations On Natural Populations And Experiments On The Role Of Maternal Diet, Carol A. Burkart Jan 1998

Variability In Copepod Hatching Success: Observations On Natural Populations And Experiments On The Role Of Maternal Diet, Carol A. Burkart

HCNSO Student Theses and Dissertations

The objectives of this study were (1) to survey the percent hatching success of eggs produced by calanoid copepod species from a variety of ecosystems (i.e., polar, temperate, and sub-tropical), (2) to describe the relationship between egg production, hatching success of Acartia tonsa and the physical and food environments of Florida Bay, and (3) to describe the relationships between hatching success and maternal diet. In order to fulfill the first objective, an incubation system was designed to allow the monitoring of eggs at sea for extended periods of time. The second objective was addressed with a series of egg production …


Center For Sustainable Agricultural Systems Newsletter, January/February 1998 Jan 1998

Center For Sustainable Agricultural Systems Newsletter, January/February 1998

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

National Organic Program Proposed Rule

National Strategy to Assist Small Farms

North Central Region SARE Offers Producer Grants

Educators Invited to Attend SARE Celebration

Integrated Farm Update: Small Grain Cover Crops in Crop/Livestock Systems

Future Food Systems: Implications for Nebraska

Symposium: Preserving Farmland, Policies and Practices


Predator Urines As Chemical Barriers To White-Tailed Deer, Jerrold L. Belant, Thomas W. Seamans, Laura A. Tyson Jan 1998

Predator Urines As Chemical Barriers To White-Tailed Deer, Jerrold L. Belant, Thomas W. Seamans, Laura A. Tyson

Vertebrate Pest Conference Proceedings: 18th (1998)

The authors assessed whether bobcat (Lynx rufus) or coyote (Canis latrans) urine could reduce white-tailed deer (Odocoileus virginianus) use of established feeding areas or trails. A four-week experiment evaluating deer use of eight feeding stations, four each with coyote or bobcat urine was conducted at a 2,200 ha fenced facility in northern Ohio with high deer densities (38/km2). At this same facility, the authors also monitored deer use of four trails where coyote urine was applied. For both experiments, urine was placed in holders positioned at ground level within 2 m of …


Fall 1998, Nsu Oceanographic Center Jan 1998

Fall 1998, Nsu Oceanographic Center

Currents

No abstract provided.


Tsw Wildlife Damage Management Working Group Newsletter:Spring 1998 - Volume 5(2) - Election Issue Jan 1998

Tsw Wildlife Damage Management Working Group Newsletter:Spring 1998 - Volume 5(2) - Election Issue

TWS Wildlife Damage Management Working Group Newsletter

Forward -- Scott Hygnstrom Postdoctoral Position With The Jack Berryman Institute; 1998 Winners Of The Jack H. Berryman Institute Awards; Preliminary Program For The Wildlife Society 5th Annual Conference, September 22-26, 1998, Buffalo, Ny; Candidates For The Working Group Executive Board Future Newsletter; Contributions; From Around The World!; Wildlife Damage Management Working Group Ballot - May 1998 ; Plenary Abstracts From The 18th Vertebrate Pest Conference, 2-5 March 1998, Costa Mesa, Ca; Available Publications; Future Events Of Interest; Next Edition Deadline; Application For Membership / The Wildlife Society; Contributors To This Issue


Energy Requirements For Certified Organic Farms In New Jersey : A Survey And Analysis Of Tomato Production, Cecilia Kelnhofer-Feeley Jan 1998

Energy Requirements For Certified Organic Farms In New Jersey : A Survey And Analysis Of Tomato Production, Cecilia Kelnhofer-Feeley

Theses

The focus of this thesis is to document the fossil fuel and electrical energy consumption required to grow certified organic tomatoes in the State of New Jersey. First, in order to evaluate the energy requirement for agriculture, a literature review of energy changes during the twentieth century is discussed. Secondly, an in-depth look at energy requirements for all farming types is evaluated. Third, previous studies of the energy requirements in agriculture are examined; this includes both analyzing organic and conventional farming practices. A survey was generated from the information gathered. The survey was conducted via face-to-face interviews. When all the …


University Of Texas At Tyler Freshman Catalog, 1998-1999, University Of Texas At Tyler Jan 1998

University Of Texas At Tyler Freshman Catalog, 1998-1999, University Of Texas At Tyler

Catalogs

Archives Space instance: https://archivesspace.uttyler.edu/repositories/2/archival_objects/22363


Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty Jan 1998

Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty

Peer Reviewed Publications

Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …


Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell Jan 1998

Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell

Bulletins 4000 -

This Bulletin was developed by Department of Agriculture in recognition of the increasing complexity and competitiveness in establishing a commercial vegetable enterprise. The information in this Bulletin will provide you with a useful guide to assess your likelihood of succeeding in vegetable production.

Vegetable production is not an easy lifestyle. It is a highly competitive environment with the industry consisting of growers with big investments and years of experience and knowledge. Horticultural farms require a large amount of capital and time and are increasingly expanding and becoming more specialised.

If you are serious about growing vegetables, work through this Bulletin …


Northern Agriculture Integrated Management Strategy - Sub-Region Strategies And Action Plans, Agriculture Western Australia Jan 1998

Northern Agriculture Integrated Management Strategy - Sub-Region Strategies And Action Plans, Agriculture Western Australia

Natural resources published reports

Greenough Sub-region

Moore River Sub-region

West Midlands Sub-region

Yarra Yarra Sub-region

The strategies and action plans contained in this document have been developed by members of the community, local industry and government agencies, representing the four sub-regions of the Northern Agricultural Region. Sub-regional strategy development has occurred due to community and agency recognition of the importance of protecting, enhancing and developing the region's valuable natural resource base.

Work began on this process with a two-day regional workshop in October 1996 and following this, numerous sub-regional meetings were held over a period of one year.

The summary of this planning work …


Glacial Deposits, Vol. 26, 1997-1998, Department Of Geography-Geology Jan 1998

Glacial Deposits, Vol. 26, 1997-1998, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston Jan 1998

Early Life History Stages Of Gulf Sturgeon In The Suwannee River, Florida, Kenneth J. Sulak, James P. Clugston

United States Geological Survey: Staff Publications

Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser ozyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the mouth of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4-7 d after the March new moon in both years and lasted 10-11 d; in 1996, a second 10-d spawning round began on the April new moon. Developmental synchrony among eggs recovered suggested serval discrete spawning events in both years. Total eggs deposited for three 1996 sampling days …