Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 13 of 13

Full-Text Articles in Life Sciences

Stubble Retention For Control Of Wind Erosion, Dan Carter, Paul Findlater, Steve Porritt Jan 1992

Stubble Retention For Control Of Wind Erosion, Dan Carter, Paul Findlater, Steve Porritt

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

The surest way to control wind erosion in continuous cropping systems is to retain stubble. Over the past ten years, Western Australian research has focused on the amounts of stubble needed to prevent that erosion.


How Arsenic Residues Get In Wool, Tony Martin, Robin Jacob, Marion Davies, Peter Rutherford Jan 1992

How Arsenic Residues Get In Wool, Tony Martin, Robin Jacob, Marion Davies, Peter Rutherford

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

Wool can become contaminated with arsenic in various ways, and several different sources may each contribute to any individual arsenic residue problem.

• dipping sheep in an arsenical dip ( now illegal),

• dipping sheep in a non-arsenical dip in a contaminated dipping facility

• penning sheep on soil with high levels of arsenic before shearing.

Other possible sources include running sheep on land contaminated by gold mine tailings or exploration sites, and allowing sheep access to sites on the farm where arsenical compounds have been dumped, for example, rubbish dumps or sites where dip/sump sludge has been dumped.

Farmers …


The Role Of Earthworms In Western Australian Agriculture, Tom Mccredie, Lex Parker Jan 1992

The Role Of Earthworms In Western Australian Agriculture, Tom Mccredie, Lex Parker

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

Earthworms have a reputation as soil builders and renovators, particularly among 'organic' farmers and gardeners. They improve soil fertility through increased aeration, aggregation, water infiltration and release of nutrients from organic matter. However, the benefits of earthworms in the wheatbelt have been doubted for many years because of their poor survival in cultivated soils.

Since cropping began in the Western Auslmlian whealbelt over 1OO years ago, the physical condition of many soils has deteriorated. The primary causes of soil degradation were the European cultivation practices used by farmers and the trampling effect of introduced animals. in particular, sheep.


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

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

Journal of the Arkansas Academy of Science

Zooplankton samples were collected quarterly from five stations representing the discharge bay and four "control" or "dispersing impact" stations. Rotifers dominated all samples numerically and by the number of taxa. All major groups (Rotifera, Cladocera, Copepoda, and Protozoa) exhibited greatest abundances during the summer. Quarterly variations in abundance and number of taxa were documented. Except for an increase in taxonomic analysis detail between 1981 and 1984 resulting in several more taxa added to the list, no long-term increases, declines or repeating cycles were apparent. Margalef's Richness Index reflected this change and showed a long-term increase with evidence of a 5- …


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 …


The Pros & Cons Of Retaining Stubble, Department Of Agriculture And Food, Western Australia Jan 1992

The Pros & Cons Of Retaining Stubble, Department Of Agriculture And Food, Western Australia

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

Few farmers in Western Australia today would question the desirability of retaining crop stubble. The problem usually is how to manage stubble so that it does not interfere with other parts of the farming system


Results Of Stubble Research In Western Australia, Michael Perry, Ron Jarvis, Mel Mason, David Tennant Jan 1992

Results Of Stubble Research In Western Australia, Michael Perry, Ron Jarvis, Mel Mason, David Tennant

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

Few farmers would question the desirability of retaining stubbles, both for control of erosion by wind and water, and to return organic matter to the soil. While the present debate is focused on the short term management of stubbles, longer term effects also need to be considered.

The Department of Agriculture has several long-running trials intended to measure long term effects.


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 …


Using Physical, Chemical And Biological Indicators To Assess Water Quality On The Ouachita National Forest Utilizing Basin Area Stream Survey Methods, J. Alan Clingenpeel, Betty G. Cochran Jan 1992

Using Physical, Chemical And Biological Indicators To Assess Water Quality On The Ouachita National Forest Utilizing Basin Area Stream Survey Methods, J. Alan Clingenpeel, Betty G. Cochran

Journal of the Arkansas Academy of Science

The Ouachita National Forest (ONF) has developed a series of Best Management Practices (BMP's) designed to protect water quality and associated beneficial uses (fisheries, municipal water supplies, etc.). A monitoring program is necessary to document the effectiveness of that protection. The Basin Area Stream Survey (BASS) methodology provides a monitoring link from BMP's to the aquatic ecosystems. The goal of BASS is to identify the physical, chemical and biological characteristics of a stream in a format that will allow comparisons with other streams, and indicate when a stream is being impacted. Six index streams within two ecoregions were selected and …


Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia Jan 1992

Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia

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

Several articles in this issue of the Journal of Agriculture discuss some of the important issues of stubble management. The articles are condensed from some of the papers presented at a stubble workshop at Geraldton in 1991.


Red Kangaroos Can Set Back Range Regeneration, Andrew Mclaughlin Jan 1992

Red Kangaroos Can Set Back Range Regeneration, Andrew Mclaughlin

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

After years of severe drought, stocking rates in Western Australia s arid rangelands have been kept low since the 1970s to allow native pastures to regenerate. As well, extensive re-seeding programs have started and sheep and cattle grazing on these areas has been restricted or eliminated. However, pasture regeneration in the rangelands can only succeed when grazing by all animals - sheep, cattle, kangaroos, goo.ts, camels, brumbies and donkeys - is controlled Many more red kangaroos roam throughout Western Australia's pastoral areas today than 20 years ago. The installation of windmills and troughs to water domestic livestock has allowed kangaroo …


Taking The Emu To Market, Paul Frapple, Ruth Hagan Jan 1992

Taking The Emu To Market, Paul Frapple, Ruth Hagan

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

Licensed, commercial emu farming in Western Australia is now five years old.

This year, 13,500 birds will be processed for their meat, skin and oil. Production has exceeded demand at prices which the industry considers fair because the industry is still developing marketd for these producys.

Without secure, long term markets, over-production will worsen as the turn-off in this State increases and emus become available from other Australian states and overseas.

The Department of Agriculture is assisting the industry to develop a viable industry.


Wider Spaced Rows For Lupins, Ron Jarvis Jan 1992

Wider Spaced Rows For Lupins, Ron Jarvis

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

In this farm scale trial at Wongan Hills, a lined combine was used to seed lupins into rows spaced 380 mm apart in wheat stubble.