Evaluating the impact of and capacity for adaptation to climate change on sectors in the sugar industry value chain in Australia.

AUSTRALIA is predicted to be hotter and generally drier, with more frequent extreme events, in coming decades similar to that expected in most sugarcane producing nations,. To assess the direct and indirect climate change impacts on the cane-growing regions of Queensland, and adaptive capacity, projections for 2030 were considered using (i) a review of literature on climate/plant interactions and sugarcane physiology, (ii) a brief qualitative assessment in collaboration with industry stakeholders throughout the value chain, and (iii) a quantitative estimate of yield potential and the efficacy of an adaptation strategy using an eco-physiological model of plant growth. The review and qualitative assessment indicated that the greatest impacts are likely to be experienced on the grower sector of the industry. Productivity gains/losses will ultimately depend on the availability of a number of resources, particularly water, and the plant’s physiological response to relative changes in all climate variables. Capacity within the sugar industry value chain is considered sufficient to absorb an increase in yield, but a decrease may financially challenge many mills. The paper then focused on providing more quantitative estimates of impact using the Agricultural Production Systems sIMulator (APSIM) to estimate yield potential in response to temperature and rainfall projections up to 2030 for the most northerly (Mossman) and southerly (Rocky Point) regions of the Queensland sugarcane industry. Response surfaces produced from model simulations suggest yield losses are likely be greater in the cooler southern regions due to increased water stress. The vast majority of adaptation strategies identified by stakeholders as potentially useful were an extension and enhancement of the current practices used to manage sugarcane production in the highly variable Australian climate. An eco-physiological model (APSIM) was used for the first time to assess the adaptive strategy of changing the date of planting in a sugarcane production system. The simulations suggest that yield potential will increase marginally if the planting date occurs earlier than presently practised in the south, while a delay in planting date in the north may increase productivity by the year 2030. This study showed that collaborative research between industry stakeholders from all sectors and the use of an ecophysiological modelling tool, such as APSIM, can aid in the identification of critical areas of climate change impact, quantify these impacts and assist in the identification of adaptation strategies at a regional scale. Introduction Sugarcane has been commercially grown on the north-eastern coastal plains and hinterlands of Australia since 1862. The production area today is over 2000 km long and regions can be categorised by the major climatic constraints that they impose on production. Potential yield can be limited in the northern region of Queensland by low levels of radiation associated with extensive cloud cover and annual rainfall in excess of 3000 mm.