Climate-change effects and adaptation options for temperate pasture-based dairy farming systems: a review



Temperate pasture-based dairy farming systems with low input of supplementary feed are vulnerable to changes in climate through alterations in feed supply and nutritive value. Although current systems in New Zealand (NZ) and southeast Australia have been successful in adapting to variable weather conditions, they will need to undergo further changes to continue to profit in the future. This review describes predicted changes in climate in NZ and southeast Australia, likely effects on the feedbase used in the pasture-based dairy industry and the flow-on effect on milk-solids production and profitability. Potential adaptation options that will allow farmers to take advantage of new opportunities and minimize any negative impacts of climate change are also identified. For example, in many regions, annual pasture production is predicted to increase due to carbon dioxide fertilization and warmer temperatures during winter/spring. Production may decline, however, in regions with either reduced rainfall or severe flooding. Should this occur, farmers could strategically use supplementary feed, reduce stocking rates, irrigate or sow alternative plant species with greater drought tolerance. Pasture-based dairy systems have high levels of adaptive capacity, and there are opportunities to continue to improve production efficiencies particularly where rainfall change is small. Further investigation into possible adaptation options is required to determine their impact on milk-solids production and profitability, as well as to identify additional options.