As the global population increases and becomes more affluent, biomass demands for food and biomaterials will increase. Demand growth is further accelerated by the implementation of climate policies and strategies to replace fossil resources with biomass. There are, however, concerns about the size of the prospective biomass demand and the environmental and social consequences of the corresponding resource mobilization, especially concerning impacts from the associated land-use change. Strategically integrating perennials into landscapes dominated by intensive agriculture can, for example, improve biodiversity, reduce soil erosion and nutrient emissions to water, increase soil carbon, enhance pollination, and avoid or mitigate flooding

The Murray–Darling basin's river system suffers from over-allocation of water resources to consumptive use and salinity threats to water quality. This paper draws attention to the current state of knowledge and the need for further investigations into the biological effect of river salinity on aquatic biota and ecosystems, the threats of dryland salinity to terrestrial biodiversity, and managing environmental flows and salinity control to limit the trade-offs in water-resource security and river salinity.There is growing evidence that river salt concentrations lower than the normally adopted threshold have sublethal effects on species and ecosystems, over a longer time period. Further knowledge is required.There is no agreed process for incorporating terrestrial biodiversity values at risk into a strategic response for dryland-salinity management. This is a public policy issue to be addressed.Recent studies have quantified the trade-off in surface water flow and river salinity from refforestation and revegetation of upland catchments to control salinity. The potential losses or benefits to environmental values have not been quantified.Such improved knowledge is important to the Murray–Darling basin and relevant to other river basins and catchments in Australia.

A synthesis of work on integrating short‐rotation biomass plantings into existing mixed crop and livestock farming regimes with the biomass being converted to biofuels, including aviation fuel, is provided. This agroforestry system, based on mallee eucalypt species native to Australia, provides broader environmental benefits, including biodiversity protection. These species are suited to the edaphic and climatic conditions of rainfed farming systems in southern Australia. The study focused on the Great Southern region of Western Australia, with an average annual rainfall of 400–600 mm. Compared to other locations in Australia, significantly more research and development has been conducted in this region, with a mallee biomass‐to‐jet fuel business case and farmer cooperation providing reliable data for assessing the viability and sustainability of commercial supply chain development. The limited capacity of Australian agricultural systems to produce biomass due to the relatively dry climate means that the available biomass resources should be directed to strategically important energy uses such as aviation fuel. Technical, economic, and environmental insights gained from these long‐term studies have demonstrated that it is feasible to integrate this new production system into the overall farming enterprise and indicate strong prospects for a biomass industry in this region should political and economic uncertainties currently facing the renewable energy industry in Australia be resolved. WIREs Energy Environ 2017, 6:e221. doi: 10.1002/wene.221 This article is categorized under: Bioenergy > Science and Materials Bioenergy > Economics and Policy Bioenergy > Systems and Infrastructure

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Introducing perennial pasture species and cultivars to Australian dryland farming systems is by no means a new concept. However, the papers in this special issue of the Australian Journal of Experimental Agriculture document a substantial and sustained research program that seeks to substantially expand the scale of their use. The focus is expansive and includes profitable and adaptive farming systems for southern and temperate Australia, extending to lower rainfall environments and a wide range of farming system applications and enterprises. Success with perennial and salt-tolerant plants will result from their adoption into grazing and cropping systems that are not only profitable, but also have the ability to exploit available water in the face of the multiple threats of drought, salinity, waterlogging and soil acidity. There can be other landscape benefits too: enhanced biodiversity, soil cover and protection of water resources. However, the introduction of new perennials plants also carries a duty of care, in particular the prevention of new weeds. The research comprehensively assessed in this issue was conducted by the Cooperative Research Centre for Plant-based Management of Dryland Salinity (CRC Salinity), a joint venture between the major primary industry research and development organisations in Australia. CRC Salinity was formed in 2001 in response to the threat of dryland salinity in Australia, which was highlighted in 2000 with the release of land and water resources and salinity audits in the run-up to the Australian Government initiating the National Action Plan on Salinity and Water Quality. However, it is now clear that actions to reverse salinity have had limited impact: for most farmers there are not yet profitable options for salinity prevention and, in many situations, the scale of the salinity threat is not as great as previously predicted.