Declining natural resources
For every one billion people added to the world’s population, 100 million more tons of rice (paddy) need to be produced annually. This must be achieved with less land, less water, and less labor, in more efficient, environmentally friendly production systems that are more resilient to climate change and with fewer greenhouse gas emissions .
Declining yields and less land, water, and labor
Yield growth has fallen, partially as a result of the decline in investment in productivity research since the early 1990s, from 2.2% during 1970–1990 to less than 0.8% in the 1990s and 2000s. Rice area in the major production countries has been decreasing because of the conversion of land for other purposes. Competition for water is becoming increasingly fierce. Fewer hands are available for farming as young people prefer to look for jobs outside the agricultural sector. Although there is still scope for expansion of rice area in the three regions, conservation of natural ecosystems must remain a high priority.
Pressure on land use
As a consequence of economic growth, current rice cultivation areas are likely to be lost to urban expansion, land conversion to biofuels, and diversification into other agricultural products. This all means that sufficient production to meet growing future demand will have to come from smaller and smaller areas, particularly if diversification is to be possible while keeping rice prices affordable to poor consumers. The main strategy must be to increase rice yields on existing land. Particularly for African and South American farmers, another challenge will be to make greater use of largely unused lowlands while preserving their ecosystem services and taking the pressure off fragile upland systems.
By 2025, 15–20 million hectares of irrigated rice will suffer some degree of water scarcity, which results from competing water uses and climate change, and requires rethinking of current management paradigms. In northwestern India, declining groundwater levels pose a serious threat to one of the world’s most important grain baskets. In fact, rice systems draw much of their ecological resilience from intensive water use and new solutions need to be found for water-scarce conditions.
Reducing the environmental footprint of rice
Intensive rice systems are often perceived as needing excessive fertilizers and pesticides, reducing biodiversity, drawing down precious water resources, or emitting large amounts of greenhouse gases such as methane. On the other hand, rice research has prevented 13 million hectares of agricultural expansion, potentially saving a commensurate area of natural ecosystems from being brought under cultivation. Recent research has yielded many new technologies that address these issues and are designed to make rice cropping systems more productive and eco-efficient. It has been demonstrated in research and in first-adoption studies that rice can be grown profitably with little use of insecticides, site-specific nutrient management that leads to 30–50% increases in nitrogen use efficiency, or water-saving irrigation techniques that result in 30% less water use and also reduce methane emissions.