干旱预警的风险抵御和节水效应研究：基于随机对照实验的实证分析

An early drought warning is a useful means to hedging against drought-related weather hazards, however farmers often have weak accessibility to drought warning due to malfunction of dissemination channels. Previous research has not studied the effectiveness of different dissemination channels that deliver drought warning to farmers. Based on a Randomized Controlled Trial, 450 farmers will be surveyed at baseline and randomized into three groups: (1) Control group (N=150) free from intervention; (2) Intervention group 1 (N=150) in which farmers will be sent text messages in the case of an early drought warning (30 days before onset of drought) is issued by the National Climate Center; and (3) Intervention group 2 (N=150), in which a social-networking intervention is used on top of the text-message intervention. A follow-up survey will then be conducted at the end of the intervention which lasts for a growing season, which allows us to evaluate the effectiveness of dissemination channels on risk-mitigation (i.e. maintaining agricultural yields and reducing production risks) and water-saving (i.e. saving water and improving irrigation water use efficiencies). The novelty of this study is that it uses a Randomized Controlled Trial to provide a precise evaluation of risk-mitigating and water-saving effects by drought warning. This study is highly policy-oriented and aims to provide comprehensive and evidence-based policy recommendations on how to deliver an early drought warning system efficiently and effectively.

干旱预警是抵御干旱风险的重要手段，但是农户往往无法收到干旱预警，主要原因是信息传播渠道的有效性较差。目前暂未出现给农户传递旱情信息并衡量其成效的研究。本项目运用随机对照实验的方法，拟对450名农户进行基线调研后分为三组：（1）“对照组”农户150名，不进行任何干预；（2）“干预组一”农户150名，根据国家气候中心公布的未来30天干旱预警情况，在旱情预警出现时通过发送“短信”方式进行干预；（3）“干预组二”150名农户，通过“短信+社会网络”方式进行干预。干预期为一个种植季，结束后进行跟踪调研获得第二期数据，由此对干旱预警的接收效果、风险抵御效应（保产、降低生产风险）、节水效应（节约用水、提高灌溉用水效率）进行评价。本文的创新点是用随机对照实验的方法准确评估干旱预警的风险抵御和节水效应，为系统深入地通过干旱预警的方式来应对干旱风险提供提出切实可行的政策建议。

本项目通过收集受干旱影响较为严重的农牧区的降雨量、温度等气候数据，结合农区和牧区牧户的入户调研数据，在此基础上创建了多套包含农户干旱预警信息接收情况、自然灾害受灾频率及损失情况、极端天气适应性措施采纳情况的一手数据库。在此基础上，本项目：（1）分析了降雨量减少和气温增加为主要形式的气候变化对农牧业生产的影响；（2）分析了干旱预警的风险抵御效应，破解了干旱预警促进农户采纳适应性措施达到减损效果的中介效应；（3）探究了农户对未来气候不确定性的风险感知对保护性耕作技术采纳的微观影响机制；（4）为政府决策部门制优化现有干旱预警政策，增强农业生产的风险抵御能力，提供了政策建议。.主要结论如下：（1）长期气温上升降低了生态脆弱区农户生产的净收益；（2）天气预警信息并没有减少农户遭受经济损失的可能性，但可以有效地减弱遭受损失的牧户的经济损失程度；（3）灾害预警信息有效促进牧民采取适应极端天气事件的各项措施，从而实现风险抵御天气风险的目的；（4）农户对天气风险的风险感知和风险偏好促进了农户采纳应对气候变化和抵抗自然灾害风险的生产技术。.依托该项目，课题主持人共发表论文7篇，包括《中国农村经济》，以及Journal of Rural Studies (IF:5.16)、Journal of Environmental Management (IF:8.91)、Science of The Total Environment (IF:10.75)、Environmental Science & Policy (IF:6.42)、Journal of Cleaner Production (IF:11.07)、International Journal of Risk Disaster Reduction (IF:4.84)等国际SCI/SSCI收录期刊。根据研究结论撰写了多份研究报告，有1份获得国务院领导批示，4份获得省部级领导批示。基于该项目支持，9名研究生参与了课题研究，合作发表了7篇论文。干旱预警相关研究成果在2021年中国农林经济管理学术年会、Sustainability and Development Conference 2022等国内外学术会议上汇报。