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Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Thermal Tolerances And Preferences Of Fishes Of The Virgin River System (Utah, Arizona, Nevada), James E. Deacon, Paul B. Schumann, Edward L. Stuenkel Oct 1987

Thermal Tolerances And Preferences Of Fishes Of The Virgin River System (Utah, Arizona, Nevada), James E. Deacon, Paul B. Schumann, Edward L. Stuenkel

Publications (WR)

Critical thermal maxima (CTM) and thermal preferenda of the common fishes of the Virgin River were examined. Differences in final temperature preferenda and CTM for species with low thermal lability (speckled dace, spinedace, roundtail chub) correspond well with differences in their distribution and abundance in the river. These species shifted their acute thermal preferences relatively little as acclimation temperature increased. For thermally labile species (woundfin, red shiner, desert sucker, and fiannehnouth sucker), the final preferendum is a less precise indicator of probable distribution. The woundfin, an endangered fish, has a high CTM (39.5 C at 25 C acclimation) and a …


Social Traps And Environmental Policy, Robert Costanza Jun 1987

Social Traps And Environmental Policy, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

In recent years, scientific understanding and public awareness of environmental problems have increased tremendously. Yet our ability to manage these problems effectively has in too many cases gotten worse, not better. By studying real-world social traps and laboratory examples, we can learn effective escapes.


Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection May 1987

Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.


Simulation Modeling On The Macintosh Using Stella, Robert Costanza Feb 1987

Simulation Modeling On The Macintosh Using Stella, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

STELLA (Structured Thinking Experimental Learning Laboratory with Animation) is a computer application for Macintosh that allows model building for the biologist.


Dust Elimination From Outdoor Feedlots For Sheep, D J. Carter Jan 1987

Dust Elimination From Outdoor Feedlots For Sheep, D J. Carter

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

The humble woodchip, widwly used as a soil mulch in Western Australian gardens, is set tto take a new role as a dust inhibito in assembly yards used to hold live sheep for export.

Research by the Department of Agriculture's Soil Conservation Service Branch has shown that, of the materials tested, woodchips were the most effective in preventing dust being generated. Wind speeds had to approach a "near gale" before dust developedfrom the protected soil.

The use of woodchips, therefore, provides a practical alternative to stabalising the soil and preventing an environmental problem associated with one of the State's valuable …


Production From Heifers And First Calvers, G J. Sawyer Jan 1987

Production From Heifers And First Calvers, G J. Sawyer

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

Heifers and first calvers present the major problems of the beef breeding herd. Reproduction rates, calf growth and survival of first calvers are generally much poorer than those of adult breeders.

Early successful reproductive performance is important in beef herds because of the high overhead cost of keeping breeding beef heifers or cows, Where possible, beef producers should aim to join heifers at 14 to 15 months of age. To achieve this goal, producers should set production targets for those animals. These targets will differ from farm to farm depending on when calves are turned off and the seasonal feed …


Seepage Interceptor Drains And Topsoil Salinity, T R. Negus Jan 1987

Seepage Interceptor Drains And Topsoil Salinity, T R. Negus

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

The Department of Agriculture established 121 trials in its Narrogin advisory district starting in 1972 to measure the effect of bulldozer and grader built seepage interceptor banks and drains on the topsoil salinity of the land downslope of them.

After 14 years of moniterin, there was no evidence that seepage interceptor drains and banks reduced the top soil salinity on 10 of the 11 sites in the Pingelly, Brookton and Wickepin Shires.


Effect Of Agronomic Practices On Wheat Protein Levels, M G. Mason Jan 1987

Effect Of Agronomic Practices On Wheat Protein Levels, M G. Mason

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

High grain protein levels are preferred for many end-uses of wheat. However, there has been little or no incentive for farmers to use practices which would increase protein levels, because wheat payments are made without a price differential for proteinlevel, except where wheat could qualify for the Australian Hard grade.


Colorado River Salinity Control Program Final Environmental Impact Statement For Big Sandy River Unit, Sublette And Sweetwater Counties, Wyoming, United States Department Of Agriculture, Soil Conservation Service Jan 1987

Colorado River Salinity Control Program Final Environmental Impact Statement For Big Sandy River Unit, Sublette And Sweetwater Counties, Wyoming, United States Department Of Agriculture, Soil Conservation Service

Environmental Assessments (NV)

No abstract provided.


Gypsum Use In The Wheatbelt, M R. Howell Jan 1987

Gypsum Use In The Wheatbelt, M R. Howell

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

One of the limitations to crop productivity in the wheatbelt is the poor structure of heavy textured soils. Many years of clearing and cultivation have caused the loss of soil organic matter and breakdown of soil aggregates - particles of sand, silt and clay - in the surface layers. This has led to the development of unstable soils with poor physical properties.

Although loss of soil structure is a serious problem, it can be reversed by altering the tillage practices that caused the problem. This improvement in soil structure and return to productivity can be a slow process. However gypsum …


Mogumber Drainage Works Succeed, L K. Lenane Jan 1987

Mogumber Drainage Works Succeed, L K. Lenane

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

The loss of arable farmland from soil erosion, waterlogging and salinity is a severe problem on some Western Australian farms.

When the arable land comprises only 40 per cent of the total area within the Mogumber Soil Conservation District, this loss is a real cause for concern. So too is the resulting damage to roads, siltation of railway culverts, and deaths of roadside trees from rising saline watertables.

However, drainage, contour and other works undertaken by the Mogumber Soil Conservation District have halted this degredation. Badly eroded areas that were fenced off now have a satisfactory ground cover. A wheat …


An Inventory And Condition Survey Of Rangelands In The Carnarvon Basin, Western Australia, A L. Payne, G F. Spencer, P J. Curry Jan 1987

An Inventory And Condition Survey Of Rangelands In The Carnarvon Basin, Western Australia, A L. Payne, G F. Spencer, P J. Curry

Technical Bulletins

The inventory and condition survey of rangelands in the Carnarvon Basin, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1980 and 1982, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers …


Forest Conservation In Nepal: Encouraging Women's Participation, Augusta Molnar Jan 1987

Forest Conservation In Nepal: Encouraging Women's Participation, Augusta Molnar

Poverty, Gender, and Youth

This issue of SEEDS focuses on ways in which women have been involved in a government forest conservation and restoration program in Nepal. As is common with many large-scale projects with a general impact, women were not a direct focus of the project's original design. As activities got underway, however, both the Nepali staff and their expatriate colleagues quickly realized that the direct involvement of women was crucial to the success of the project's participatory strategy. Over the initial five years, 1980 to 1985, a number of approaches to addressing women's needs and generating their active participation were tried. The …