Stanford Iran 2040 Project, Hamid and Christina Program in Iranian Studies, Stanford University, Stanford, CA, 94305, USA.
Centre for Environmental Policy, Imperial College London, London, SW7 2AZ, UK.
Sci Rep. 2017 Aug 9;7(1):7670. doi: 10.1038/s41598-017-08066-y.
Increasing population has posed insurmountable challenges to agriculture in the provision of future food security, particularly in the Middle East and North Africa (MENA) region where biophysical conditions are not well-suited for agriculture. Iran, as a major agricultural country in the MENA region, has long been in the quest for food self-sufficiency, however, the capability of its land and water resources to realize this goal is largely unknown. Using very high-resolution spatial data sets, we evaluated the capacity of Iran's land for sustainable crop production based on the soil properties, topography, and climate conditions. We classified Iran's land suitability for cropping as (million ha): very good 0.4% (0.6), good 2.2% (3.6), medium 7.9% (12.8), poor 11.4% (18.5), very poor 6.3% (10.2), unsuitable 60.0% (97.4), and excluded areas 11.9% (19.3). In addition to overarching limitations caused by low precipitation, low soil organic carbon, steep slope, and high soil sodium content were the predominant soil and terrain factors limiting the agricultural land suitability in Iran. About 50% of the Iran's existing croplands are located in low-quality lands, representing an unsustainable practice. There is little room for cropland expansion to increase production but redistribution of cropland to more suitable areas may improve sustainability and reduce pressure on water resources, land, and ecosystem in Iran.
人口增长给农业在未来保障粮食安全方面带来了难以逾越的挑战，尤其是在中东和北非（MENA）地区，那里的自然条件不利于农业发展。伊朗作为 MENA 地区的主要农业国，长期以来一直致力于实现粮食自给自足，但该国土地和水资源实现这一目标的能力在很大程度上尚不清楚。本研究利用高分辨率空间数据集，根据土壤特性、地形和气候条件，评估了伊朗土地可持续作物生产的能力。我们将伊朗的土地适宜性分为以下几类：非常适宜（0.6%）、适宜（3.6%）、中等适宜（12.8%）、不适宜（97.4%）和不适宜种植区（19.3%）。除了降水不足造成的总体限制外，低土壤有机碳、陡峭坡度和高土壤钠含量等土壤和地形因素是限制伊朗农业土地适宜性的主要因素。约 50%的伊朗现有耕地位于低质量土地上，这是一种不可持续的做法。虽然增加耕地面积以提高产量的空间很小，但将耕地重新分配到更适宜的地区可能会提高可持续性，并减轻伊朗水资源、土地和生态系统的压力。
