Department of Horticulture, College of Aburaihan, University of Tehran, Tehran, Iran.
Department of Irrigation and Drainage, College of Aburaihan, University of Tehran, Tehran, Iran.
PLoS One. 2019 Jun 27;14(6):e0218725. doi: 10.1371/journal.pone.0218725. eCollection 2019.
Due to higher temperatures and lower water availability, climate change is likely to have a major impact on walnut production in the near future. Climate change will alter the land suitability for walnut cultivation around the world, especially in arid and semi-arid regions like Iran. Here, land suitability for the cultivation of walnut (Juglans regia L.) in Iran was determined using the GIS for present and future conditions (2020-2049) with an approach to climate change. Accordingly, data from 375 synoptic stations throughout Iran were gathered for climatic factors including average, minimum and maximum temperatures, relative humidity and chilling requirement. Also, ASTER sensors (Advanced Spaceborne Thermal Emission and Reflection Radiometer) and their data provided this research with cells that make a precision of 150 m (5 s), and the data were used for gauging geological parameters such as altitude and land slope. The electrical conductivity (EC) of soil and water were informed by the data bank of the Iranian Water Resources Management. The results of temperature simulations for the future (2020-2049) were analyzed by 21 AOGCM-AR5 models under the RCP4.5 emission scenario. In the first phase of evaluations, the maps of land suitability were constructed for present conditions by considering a network of the above-mentioned parameters. By combining these layers of information, the final map of land suitability was illustrated for walnut cultivation. In the second phase, the NEX-GDDP was used in order to determine land suitability for the future (2020-2049). The results showed that Iran currently has 582844 km2 of land suitable for walnut cultivation. However, the future will see less suitable lands: the current area will be reduced by 6.19%, from 582844 km2 to 546710 km2. In general, the northern, northwestern and western margins of Iran are currently suitable for walnut cultivation. By approximation, these lands will also be major areas for prospective cultivations of walnut in the future (2020-2049), even though their current stretch will be reduced.
由于温度升高和可用水资源减少，气候变化很可能在不久的将来对核桃生产产生重大影响。气候变化将改变全球范围内适合核桃种植的土地，特别是在伊朗等干旱和半干旱地区。在这里，利用 GIS 确定了伊朗核桃（Juglans regia L.）种植的土地适宜性，方法是考虑到气候变化的现状和未来条件（2020-2049 年）。因此，收集了来自伊朗 375 个气象站的气候因素数据，包括平均、最低和最高温度、相对湿度和需冷量。此外，ASTER 传感器（高级星载热发射和反射辐射计）及其数据为这项研究提供了精度为 150 米（5 秒）的单元格，并且使用这些数据来衡量海拔和土地坡度等地质参数。土壤和水的电导率（EC）由伊朗水资源管理局的数据银行提供。未来（2020-2049 年）的温度模拟结果由 21 个 AOGCM-AR5 模型在 RCP4.5 排放情景下进行了分析。在评估的第一阶段，通过考虑上述参数网络，为现状构建了土地适宜性图。通过组合这些信息层，绘制了核桃种植的最终土地适宜性图。在第二阶段，使用 NEX-GDDP 来确定未来（2020-2049 年）的土地适宜性。结果表明，伊朗目前有 582844 平方公里的土地适合核桃种植。然而，未来的适宜土地将减少：目前的面积将减少 6.19%，从 582844 平方公里减少到 546710 平方公里。总的来说，伊朗的北部、西北部和西部边缘地区目前适合核桃种植。大致来说，这些地区也将是未来（2020-2049 年）核桃种植的主要地区，尽管它们目前的面积将会减少。
