17 pages, Southern Australian farming systems operate predominantly under Mediterranean climatic conditions, which limit the choice of cover crops suitable for enhancement of ground cover and soil moisture retention, erosion control, atmospheric soil nitrogen (N) fixation, and weed suppression between cash crop rotations. Given that the successful establishment of cover crops is climate-driven and also influenced by edaphic factors such as soil pH and salinity, there has been increased interest by southern Australian producers in identifying potential cover crop species well adapted to specific Australian farming systems, which provide vital ecosystem services and sustainable economic benefits through the improvement of soil properties. This review summarises recent findings on cover crop inclusion in diverse farming systems in southern Australia, including continuous and mixed broadacre cropping as well as viticulture and horticulture systems, to identify opportunities and limitations related to their use. Cover crop inclusion in viticulture and pasture systems with lower moisture stress was observed to benefit the subsequent cash crop through enhanced production potential. Long-term, multi-site field experimentation incorporating summer cover crops in winter crop rotations showed that cover crops enhanced ground cover and soil water infiltration in some locations across southern Australia while sometimes increasing winter crop yield, suggesting that soil type and regional climatic conditions greatly influenced the delivery of multiple cover crop benefits. Collectively, these studies have suggested a need for longer-term field evaluations using multiple cover crop species and investigations of termination options under varying environmental and soil conditions to better quantify the legacy effects of cover crops.
8 pages, In the face of rapidly advancing climate change, biodiversity loss, and water scarcity, it is clear that global agriculture must swiftly and decisively shift toward sustainability. Fortunately, farmers and researchers have developed a thoroughly studied pathway to this transition: agroecological farming systems that mimic natural ecosystems, creating tightly coupled cycles of energy, water, and nutrients. A critical and underappreciated feature of agroecological systems is that they replace fossil fuel- and chemical -intensive management with knowledge-intensive management. Hence, the greatest sustainability challenge for agriculture may well be that of replacing non-renewable resources with ecologically-skilled people, and doing so in ways that create and support desirable rural livelihoods. Yet over the past century, US agriculture has been trending in the opposite direction, rapidly replacing knowledgeable people with non-renewable resources and eroding rural economies in the process. Below, we suggest how US policy could pivot to enable and support the ecologically skilled workforce needed to achieve food security in the face of climate change.
