b'Session VI: Decision Support ToolsOverseer, the story of a New Zealand decision support toolsupporting sustainable farming practice.Read C11Overseer Limited, Level 4, 2 Woodward Street, Wellington 6143, New ZealandAgriculture is critical to a healthy New Zealand economy. This is because it is the largest trading sector in New Zealand, contributing approximately 5% ($NZ10.6 billion = 6.07b) to the countrys Gross Domestic Product (GDP). In 2017, agricultural products made up 60% of merchandised exports valued at $NZ36b, of which pastoral farming made up $NZ21b. The sector is also one of New Zealands largest employers, directly employing 136,500 people in 2012 with a large and growing service industry.While we have traded off a clean-green image based on significant natural environmentalassets (30% of New Zealand is in protected parks) and our rural landscapes, the intensification of farming since the 1990s has led to degradation of water quality over the last generation in rural areas.The Prime Minister recently announced at the UN Climate Change Summit in New York that New Zealand would lead the way on international collaboration on agriculture and was determined to show that we can be the most sustainable food producers in the world.In New Zealand the approach to addressing environmental sustainability is based on a unique piece of legislation, the Resource Management Act, that uses participatory democracy and a permissive approach that deals with the effect an activity has on the environment. Controlling diffuse nutrient losses from farmland is only possible if you understand what the losses are, whats causing them and how to reduce it. Until now, this information has not been easily available to farmers, and so change has been slow and sporadic.Overseer was developed in the 90s to bring science to the process of recommending fertilisation levels for farms and making better use of nutrients in effluent. However, its value in identifying farm-specific options to reduce diffuse losses (nitrate leaching and greenhouse gas emissions) has taken a long gestation time, not until public perception around the impact on water quality of agricultural intensification has become a key tool in the management of water quality.This presentation will describe the role of Overseer in supporting targeted management of farm losses and how it is now adding significant value as a decision support tool through connecting farmers and their advisers to the science they need to develop environmentally and economically sustainable farm systems.29'