English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Combinations of climatic factors and potential policy initiatives such as Sustainable Diversion Limits (SDLs), which define water diversions for consumption while maintaining environmental assets and ecosystem functions, will continue to challenge water resource management in the future. Irrigation currently consumes major share of water entitlements and is likely to be affected in terms of reduced yield and quality as a result of reduced water availability. Previous studies have quantified the economic impacts of water sharing and climate change by only changing irrigable area as a response to variations in water availability. In this study we incorporate complex crop water profit functions, irrigation technology, alternative cropping systems and detailed environmental responses to capture economic and environmental tradeoffs under different climate scenarios and SDLs. Economic and environmental tradeoffs are valued in terms of opportunity cost of foregone agricultural profit and benefit transfer from existing environmental valuation studies. This paper presents environmental and economic responses in the Broken River catchment to analyse alternative water sharing arrangements and examine the tradeoffs. The modelling framework includes a diverse range of tools. Irrigator demand was modeled through representative farm models for irrigated dairy, horticulture and cropping and fodder industries providing optimal water use at the farm level. These were scaled up to the catchment level according to land use areas. The technical coefficients for representative farm models were obtained from experimental trials and biophysical modeling tools, such as DairyMod and APSIM, which provide a way of assessing the impact of a range of changes on pasture systems. The objective function in the model was the maximization of the total gross margin for the farm and subject to constraints. Gross margin was defined as the difference between returns from agricultural produce plus stock sales and variable costs. The environmental assets of concern were native fish, macro invertebrates, riverine vegetation and geomorphology. An expert panel of scientists was formed to consider these categories of environmental requirements (assets) and developed a set of priorities to achieve asset improvement and maintenance of ecosystem functions. Augmented flow requirements for the maintenance of environmental assets were quantified by eflow predicter developed by the eWater Cooperative Research Centre (CRC),against the base line historical regulated river flow. The allocation of water to meet environmental demands was simulated using a daily water resources allocation simulation model Source River developed by eWater CRC, which includes representations of different demands, stream flow and the effect of water supply system constraints. Implications of varying simulated allocations to environmental and irrigation demand were quantified. With decreasing allocation, relative to demand, the economic benefit (for agricultural demand) and the environmental benefits (for the environmental demand) were compromised. Results from the analysis depended on the types of analysis and units of measurement. Environmental outcomes for native fish populations and riverine vegetation were presented in meeting the objectives of environmental improvement specified in the Water Act 2007. Farm-level results were presented as changes in total farm gross margin. Catchment water supply outcomes were presented as changes in stream flows associated with different water sharing rules. These outcomes can be useful for valuing environmental flows by applying benefit transfer of environmental values.

An environmental economic assessment of water sharing alternatives for the Broken catchment in Northern Victoria