Which Indicators Can Track Progress Towards Green Growth in Agriculture?
In order to assess if policies and actions by farmers are delivering green growth it is necessary to measure performance. This is complex, not only because of the range of environmental impacts across air, land, and water resources, but also because of the specific agro-ecological context in different countries and the fact that some impacts take a long time to appear, such as the impact of agriculture on GHG emissions and on climate change. And making comparisons across countries is a big challenge, made complex by the lack and variability of data.
The OECD has made a first attempt at developing green growth indicators for agriculture (OECD 2014). Among the indicators developed by the OECD, those shown here are the most robust, and comparable across countries over a long time period using a common methodology. Figure 3.1 shows that while agricultural gross domestic product (GDP) and carbon productivity for agriculture have steadily increased since 1990, GHG emissions have fallen slightly over the last 20 years, meaning that GHGs per unit of agricultural output have decreased significantly—a clear case of economic/environmental decoupling.
A similar development is apparent in Fig. 3.2, which shows the trends in nutrient balances (nitrogen and phosphorous) per hectare of agricultural land since 1990. The nutrient balance shows the difference between nutrients available and used by agriculture. A surplus shows that excess nutrients (fertilisers and manure) are passing into the environment, in particular watercourses, causing eutrophication and pollution. Although there is a very wide range of nitrogen balances across countries—very
Fig. 3.1 GHG emissions, GDP, and productivity for agriculture in the OECD area. Source: OECD Secretariat calculations based on data from UNFCCC and FAOSTAT
Fig. 3.2 Nutrient balance intensity and agricultural production, OECD area, 1990-2009. Source: OECD Secretariat
high in the Netherlands, Belgium, Japan, and Korea due to intensive agricultural systems but much lower in Australia, New Zealand, and North America—overall in the OECD the trend shows a reduction in surpluses.
There are many reasons for the trends—the price of inputs (fertilisers and energy) relative to outputs, and better information and farm management, but a significant factor is likely to have been policy reforms.
Those reforms have provided less incentive to overuse environmentally damaging inputs and farm practices, penalising farmers for environmental damage (polluter pays principle) and providing agricultural support conditional upon undertaking environmentally beneficial actions (cross compliance)—decoupling support from production leading to decoupling of environmental outcomes from production activities.