1990-2015年中国工矿用地扩张及其对粮食安全的潜在影响

Potential impacts of industrial land expansion on food security in China, 1990-2015

中国城市化和工业化进程所带来的粮食安全问题一直是政府和学术界关注的焦点。中国近25年来快速的城市化与工业化导致耕地资源减少和环境污染加剧,对国家粮食安全和农业可持续发展产生一定影响。本文基于中国土地利用/覆盖变化最新解译结果和中国分县粮食产量数据,重建了中国1 km分辨率的粮食产量空间数据,分析了中国1990-2015年工矿用地扩张及其对粮食产能的影响。结果表明:中国工矿用地面积在1990-2015年间增长了326%,扩张速率从1990-2000年的288 km^2/a增加到2000-2010年的1482 km^2/a,近5年(2010-2015年)扩张速率最快,达2600 km^2/a。过去25年间工矿用地扩张导致耕地面积减少1.7×104km2,直接导致粮食产能损失约6.49Mt(106t),因工矿用地扩张可能会对周边耕地污染等间接影响的粮食产量达83.20 Mt。经评估,国家工矿用地扩张对粮食产能潜在影响总体上是当前粮食总产能的17%。在空间分布特征方面,工矿用地扩张对粮食产能的直接影响呈现由东部沿海地区向西北地区逐渐减小趋势;间接影响在中部和西部地区相对较大。

Food security is a key governmental and academic concern in China. In the past 25 years, due to the rapid industrialization and urbanization, competition for land resources and environmental pollution threatened the sustainability of China’s grain production. Studies to date have focused on the urbanized areas, and rural industrial land expansion and impact on food security in China remain largely unknown. This study constructed an 1 km resolution grain output dataset using the latest remote sensing data-derived land use dataset（NLUDChina） and county-level grain production data of China to evaluate the impacts of industrial land expansion and pollution on food security of the country. The results show that the industrial land area increased by 326%between 1990 and 2015, with an increasing expansion rate of 288 km^2/a in the 1990 s to 2600 km^2/a in 2010-2015, close to the current urban expansion rate（3000 km^2/a）. During 1990-2015, industrial land expansion led to1.7 × 104km2 reduction of crop land, resulting in a direct production loss of 6.49 Mt（106tons）. Indirect losses caused by industrial pollution was conservatively estimated at 83.20 Mt. Overall estimated losses due to industrial land influence can be up to 17% of China’s cropland production. Spatially, direct loss of crop production in China decreased from the central and coastal region to the northwest region. In the central and western regions losses caused by soil pollution is relatively serious. With the increasing population and other socioeconomic and environmental changes, the balance between the supply and demand of food becomes more delicate. Therefore, remote sensing monitoring of crop land and industrial land for national macroeconomic development and environmental protection is of great significance.