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Low-Emission Beef Production In The Southern Rangelands Of Western Australia: An Analysis Of Herd Structure And Stocking Rate Experiencing Droughts, Christophe D'Abbadie

Animal Production and Livestock Research Articles

Reconciling profitable cattle production with rangeland health and reduced emissions is a key challenge in the southern rangelands of Western Australia (WA). Stocking rate and herd structure selection are crucial decisions to achieve this balance. This study assessed the emission profiles of three contrasting herd structures (weaner production, live export, and slaughter production), and three stocking rates within a herd–carbon accounting modelling framework. The analysis considers the impact of varying drought frequencies on these cattle production systems. Herd models were developed for the semiarid southern WA rangelands. Stocking rates were set at 100%, 80% and 66% of the government recommended …

Density-Dependence Inside A Marine Protected Area Increases Natural Mortality And Stunts The Growth Of A Spiny Lobster, Simon De Lestang, Emma Jade Tuffley

Fisheries Research Articles

Sustainable fisheries management often requires the modelling of stocks under unfished conditions, when the influence of population densities on animal growth and mortality can be substantial. This can be especially true for species such as spiny rock lobster, which are very habitat specific. Using western rock lobster (Panulirus cygnus) tag-recapture data from adjacent and similar fished and unfished areas, the key life history parameters of natural mortality and growth were examined and compared under different population density scenarios. In an area representative of virgin biomass levels, lobsters exhibited reduced growth rates and a substantially higher rate of natural mortality …

Revealing The Impact Of Spatial Bias In Survey Design For Habitat Mapping: A Tale Of Two Sampling Designs, Stanley Mastrantonis, Tim J. Langlois, Ben Radford, Claude Spencer, Simon De Lestang, Sharyn Hickey

Fisheries Research Articles

Submerged aquatic vegetation, referring to benthic macroalgae and plants that obligately grow underwater, are critical components of marine ecosystems and are frequently found to provide preferential recruitment habitats. The mapping and monitoring of aquatic vegetation through remote sensing and machine learning is becoming an important aspect of managing coastal environments at scale. Accurate mapping and monitoring require robust sampling and occurrence data to assess predictive error and quantify submerged vegetation extents. The form of ground truthing survey design (preferential, random, grid-based or spatially balanced) could significantly influence predictive model outcomes and the overall accuracy of mapping and monitoring. Here, we …

Agricultural Groundcover Update April 2024, Justin Laycock

Natural resources published reports

• In April, over 12% (1,876,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.
• Northern grainbelt had the highest risk of wind erosion and over 26% of this farmland had inadequate groundcover, predominantly found on landscapes known for sandy soils.
• About 1.5% (238,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Agricultural Groundcover Update May 2024, Justin Laycock

Natural resources published reports

• In May, over 9% (1,410,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.
• Northern grainbelt had the highest risk of wind erosion and over 26% of this farmland had inadequate groundcover, predominantly found on landscapes known for sandy soils.
• About 1.3% (208,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%. Half of this land was in the West Midlands Ag Soil Zone.

Heavy Steers And Heifers Run At Low Stocking Rates Enhance Drought Resilience In A Pastoral Region Of Australia, Christophe D'Abbadie, Ross Kingwell, Philip E. Vercoe, Bradley Plunkett, Alan Peggs

Animal Production and Livestock Research Articles

CONTEXT

The semi-arid mulga lands of the Southern Rangelands of Western Australia experience frequent droughts. Maintaining a profitable animal grazing enterprise whilst preserving rangeland condition requires selecting an appropriate stocking rate and herd structure.

OBJECTIVE

We construct and apply bioeconomic models of beef enterprises for the semi-arid Southern Rangelands of Western Australia, to assess the profitability and relative riskiness of three different livestock production systems and three different stocking rates when exposed to different frequencies of drought.

METHODS

We construct bio-economic models of herd structures that separately focus on producing either: (i) 200 kg heifers and 210 kg steers (ii) …

Including Methane Emissions From Agricultural Ponds In National Greenhouse Gas Inventories, Martino E. Malerba, Tertius De Kluyver, Nicholas J. Wright, Odebiri Omosalewa, Peter I. Macreadie

Climate Science Research Articles

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the …

Consultation Summary For Proposed Declared Pest Rates 2024/2025, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

Before determining a rate, the Minister for Agriculture and Food is required to consult with owners of the land to be rated, as described in the Biosecurity and Agriculture Management (Declared Pest Account) Regulations 2014 (the Regulations).

The annual process for consultation enables the Department of Primary Industries and Regional Development (DPIRD) to gauge landholder perception on the proposed Declared Pest Rate (DPR) in accordance with the Regulations.

Agricultural Groundcover Update March 2024, Justin Laycock

Natural resources published reports

• In March, over 10% (1,577,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.

• The northern grainbelt had the highest risk of wind erosion and over 20% of this farmland had inadequate groundcover.

• About 1.3% (191,000 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Agricultural Groundcover Update February 2024, Justin Laycock

Natural resources published reports

• About 92% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in February 2024.

• Nearly 8% of the grainbelt (1,193,400 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion.

• The northern grainbelt had the highest risk of wind erosion and 16.5% of this farmland had inadequate groundcover.

• Less than 0.7% of the grainbelt had a high to very high risk of wind erosion because groundcover was less than 30%.

Procedures For Rangeland Condition Assessment In The Pilbara And Southern Rangelands 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

To define the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Pilbara and southern rangelands region which has predominantly shrub-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Kimberley which has grass pastures.

RCA is the process DPIRD uses to make systematic, lease level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition and management guide for the Pilbara rangelands or Southern rangelands pasture condition and management guides) and soils …

Procedures For Rangeland Condition Assessment In The Kimberley 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

This report defines the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Kimberley region which has grass-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Pilbara and southern rangelands which have predominantly shrub pastures.

RCA is the process DPIRD uses to make systematic, lease-level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition guide for the Kimberley, Ryan et al. 2013) and soils as determined by erosion, using the …

Trends In Catch Rates Of Sawfish On The Australian North West Shelf, C. Wakefield, S. J. Newman, M. Braccini, A. Harry

Fisheries Research Articles

Northwestern Australia is thought to have some of the world’s last remaining viable sawfish populations, although little quantitative data exists on their status or trends. This study examined 17 years of logbook bycatch records (n = 815) for green sawfish Pristis zijsron and narrow sawfish Anoxypristis cuspidata from a trawl fishery operating on the Australian North West Shelf. Incidental sawfish captures by the fishery are rare, occurring approximately once every 75 trawls (~199 trawl hours). To standardize catch rates and account for excess zeros in the data, we employed generalized additive models for location, scale, and shape (GAMLSSs) using a …

Long Term Sustainable Use Of Demersal Gillnet And Demersal Longline In Western Australia’S Temperate Shark Fisheries - Fisheries Research Report 340, Matias Braccini, Jack Parker, Daniela Waltrick, Maddison Watt, Nick Blay, Clinton Syers

Fisheries research reports

The Temperate Demersal Gillnet and Demersal Longline Fisheries (TDGDLF) are one of the main commercial shark fisheries in Australia. Most fishers in the TDGDLF use demersal gillnets to target sharks with scalefish taken in smaller amounts. Demersal longlines are also permitted but are not widely used. Demersal gillnets are size selective, but they do not necessarily discriminate among species, catching target and non-target species.

The Western Australian Fishing Industry Council (WAFIC) received funding as part of the Australian Government’s Our Marine Parks Grants Program to undertake research on the TDGDLF. This project was administered under the direction of a steering …

Agricultural Groundcover Update January 2024, Justin Laycock

Natural resources published reports

Summary

• About 94% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in January 2024.
• In the northern half of the grainbelt, a larger-than-average area has 51–60% groundcover, which is expected to decrease to below 50% over the coming months.
• Just under 6% of the grainbelt (855,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. West Midlands Ag Soil Zone had the highest risk of wind erosion and 14.5% of this farmland had inadequate groundcover.
• Less than 0.5% of the grainbelt had a high to very high risk of wind …

Exact Testing For Heteroscedasticity In A Two-Way Layout In Variety Frost Trials When Incorporating A Covariate, Angelika A. Pilkington, Brenton R. Clarke, Dean A. Diepeveen

Grain and Other Field Crops Research Articles

Two-way layouts are common in grain industry research where it is often the case that there are one or more covariates. It is widely recognised that when estimating fixed effect parameters, one should also examine for possible extra error variance structure. An exact test for heteroscedasticity, when there is a covariate, is illustrated for a data set from frost trials in Western Australia. While the general algebra for the test is known, albeit in past literature, there are computational aspects of implementing the test for the two way when there are covariates. In this scenario the test is shown to …

Weed Seed Wizard Scenario - Herbicide Resistance In Wild Oats In Wagga Wagga, New South Wales, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This New …

Weed Seed Wizard Scenario - Herbicide Resistance In Wild Radish In Moora, Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This Western …

Weed Seed Wizard Scenario - Glyphosate Resistance In Barnyard Grass In Goondiwindi, Queensland, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This Queensland …

Agricultural Groundcover Update December 2023, Justin Laycock

Natural resources published reports

Summary

• About 96% of the grainbelt had adequate vegetative groundcover (more than 50%) to prevent wind erosion in December 2023.
• In the northern half of the grainbelt, a larger-than-average area has 51–60% groundcover, which is expected to decrease to below 50% over the summer.
• Just under 4% of the grainbelt (553,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. West Midlands Ag Soil Zone had the highest risk of wind erosion and 11.4% of this farmland had inadequate groundcover.
• Less than 0.5% of the grainbelt had a high to very high risk of wind erosion …

Soil And Fertiliser Management For Orchards In The Manjimup District, Neil Lantzke, Simon Yeap, Lukasz Kotula, B Goldspink, Valeria Almeida Lima, John Kammann

Horticulture research reports

This publication aims to give orchardists a broad understanding of the soils in the Manjimup district. It provides information on soil and fertiliser management that will assist in the sustainable production of fruit crops. This document was prepared for a Soils Course for horticulturalists, that was held in September 2023 at Manjimup Horticultural Research Centre.

The Manjimup local government area (LGA) is the most important horticultural district in Western Australia, particularly for fruit and in 2020 the total value of horticultural production was valued at $236 million (Figure 1). Avocados and apples were the most valuable horticultural crops, valued at …

Regional Price Index 2023, Department Of Primary Industries And Regional Development, Western Australia

Statistics

The 2023 Regional Price Index (RPI) is the eleventh State Government Index contrasting the cost of a common basket of goods and services at a number of regional locations to the Perth metropolitan region. The RPI is used as the basis for the construction of the public sector district allowance, and by the private sector when considering remuneration packages for remotely located staff.

The RPI provides an insight into differences in regional consumer costs. The 2023 RPI basket of 185 goods and services was priced in 39 regional centres around Western Australia.

The 2023 RPI results show that, overall, prices …

Weed Seed Wizard Case Study - Grower From Western Australia’S Central Wheatbelt, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This case …

Weed Seed Wizard Case Study - Don't Stop Harvest Weed Management Because It’S A Dry Year, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This case …

Weed Seed Wizard Scenario - Dormancy Shift In Barley Grass In Balaklava, South Australia, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This South …

Weed Seed Wizard Case Study - An Early Harvest Versus A Late Harvest, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity research reports

The Weed Seed Wizard is a national collaborative project that uses paddock management information to predict weed emergence and crop losses now and in the future.

The Weed Seed Wizard is a computer simulation tool that:

• applies to all Australian grain growing areas

• helps growers understand and manage weed seedbanks on their farms

• uses farm management records to simulate how different crop rotations, weed control techniques, irrigation, grazing and harvest management tactics can affect weed numbers, the weed seedbank and yields

• uses farm-specific management and site-specific weather

• is multi-species

See www.dpird.wa.gov.au for further information on Weed Seed Wizard.

This case …

Estimating Soil Texture By Hand, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Estimating or measuring soil texture provides valuable information about soil properties affecting crop and pasture growth. Soil texture affects the movement and availability of air, nutrients, and water in soil. A simple and quick measure of soil texture is the way a soil feels when manipulated by hand.

The department recommends laboratory testing of soil texture (and other factors) for all critical soil uses, including farm dam construction and claying.

Costs Of Wind Erosion In The Northern Agricultural Region, Anne Bennett

Natural resources published reports

Summary

• To date, the Department of Primary Industries and Regional Development’s (DPIRD) estimated opportunity cost of wind erosion for Western Australia’s (WA) agricultural region has only included the costs of forgone production income and therefore underestimates the broader costs of wind erosion events.
• This underestimation of costs was the impetus to create a case study to give an indication of the magnitude of the costs of wind erosion from agricultural land.
• Farmers in the Northern Agricultural Region (NAR) were contacted to seek information about the on-farm costs of wind erosion events that occurred in 2020. Seventeen farmers responded to the …

Agricultural Groundcover Update November 2023, Justin Laycock

Natural resources published reports

Summary

• About 98% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in November 2023. This amount of groundcover is normal for the middle of harvest.
• In the northern half of the grainbelt, a larger-than-average area had 51–60% groundcover, which is expected to decrease to below 50% over summer.
• Just over 2% of the grainbelt (324,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. Mullewa to Morawa Ag Soil Zone had the highest risk of wind erosion and 9.7% of this farmland had inadequate groundcover.
• Less than 0.5% of the …

Status Of The Western Australian Pastoral Rangelands 2023: Total Vegetative Cover And Cover Risk, Department Of Primary Industries And Regional Development

Natural resources published reports

The Department of Primary Industries and Regional Development (DPIRD) monitors and reports on the vegetation condition of pastoral rangelands in Western Australia. This 2023 short report uses remotely sensed total cover data available to the end of October 2023, rainfall data to the end of November 2023 and Stock Return data reported in 2022 (the most recent available) to determine cover risk. Cover risk at the land conservation district (LCD) level is an indicator of the likelihood of total cover declining to, or remaining at, low or very low levels. Total cover and cover risk may not be indicative of …