Water saving in crop production under climate and environmental changing conditions represents a critical issue for agricultural economy and sustainability. This study develops a novel approach to measure the impact of climate variability on crop water requirement at regional level. Firstly, a model where crop water requirement is the dependent variable and some climate variables are the covariates is estimated by using geographically weighted regression to consider different spatial characteristics of the regions. Then, local regression results are integrated to develop two composite indicators able to highlight critical areas in terms of water requirement and to support local policies and practices. The empirical analysis concerns the maize crops production of Italian provinces for 2017. The results point out the existence of great differences between North and South of Italy, where the impact of temperature variability tends to be more severe. The evidences also offer insights for regional planning and economic policies. The proposed methodology is very general and allows for a wider reproducibility for other crops and countries.

气候和环境变化条件下作物生产中的节水是农业经济和可持续性的关键问题。这项研究开发了一种新颖的方法来衡量气候变化对区域一级作物需水量的影响。首先，通过使用地理加权回归考虑该地区不同的空间特征，估算了以作物需水量为因变量，某些气候变量为协变量的模型。然后，将当地的回归结果进行整合，以开发出两个综合指标，这些指标可以突出显示需水量的关键领域并支持当地的政策和实践。实证分析涉及意大利各省2017年的玉米作物产量。结果指出，意大利北部和南部之间存在巨大差异，温度变化的影响往往更加严重。这些证据还为区域规划和经济政策提供了见识。拟议的方法非常笼统，可为其他作物和国家提供更大的可重复性。