Food security has received considerable attention in China for a long time because of the great challenges of population growth, shrinkage of cropland area, degradation of soil fertility, water scarcity, and climate change.

Changes in land use have generally been considered to be regional issues. While they have enabled humans to appropriate an increasing share of the planet’s resources, they also potentially undermine the capacity of ecosystems to sustain food production.

Researchers therefore face the challenge of managing tradeoffs between quantity and quality of the land, in which the use has changed, and maintaining land of sufficient quality and quantity to provide food in the long term.

Dr. SHI Wenjiao, Prof. TAO Fulu and Prof. LIU Jiyuan, from Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, analyzed changes in quantity and quality of cropland in the Huang-Huai-Hai Plain of China during the last 30 years and the implications for future grain production.

They found that the greatest decline of grain production in cropland area occurred as a result of the expansion of economically developed metropolises or in provinces with large areas of urbanization. Furthermore, conversion of fertile and irrigated land to non-agricultural uses due to rapid urbanization appears to be a potential threat to the food security of the Huang-Huai-Hai Plain. Most of the increase of grain production in the Plain can be attributed to increase in yield per hectare, which was due to improvement of crop varieties, a ~400 % increase in fertilizer use and a ~20 % increase in effective irrigation area.

The related results have been published in the journal of Food Security (Shi Wenjiao, Tao Fulu, Liu Jiyuan. Changes in quantity and quality of cropland and the implications for grain production in the Huang-Huai-Hai Plain of China. Food Security. 2013. 5(1): 69-82).

Irrigation levels of cropland areas converted and urbanized during the periods 1990–2000 and 2000–2005 areas expressed as percentages (Imaged by SHI Wenjiao)