Estuaries are coastal systems particularly vulnerable to climate change. Within these systems, agriculture is one of the most potentially affected sectors. This paper proposes a risk assessment approach for helping the decision-making process at a local level, addressing two risks that affect agricultural areas located in estuarine margins: the unavailability of freshwater for irrigation resulting from the upstream propagation of estuarine brackish water during droughts and land inundation by high water levels associated with high tides and storm surges. For each risk, quantitative consequence descriptors are proposed to support risk level determination and evaluation through a continuous consequence–probability diagram. The approach applicability is discussed through its application to the Lezíria Grande de Vila Franca de Xira, located in the Tagus Estuary (Portugal). Results indicate that the approach is appropriate to support risk owners in taking actions to mitigate the risk. Examples of risk control measures for the risks addressed are presented. The main strengths of the proposed approach are its flexibility to be adapted to local conditions and updated through time, as well as the ease of its application by the risk owner.

中文翻译：

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农业区洪水和干旱风险评估（葡萄牙塔霍河口）

河口是沿海系统，特别容易受到气候变化的影响。在这些系统中，农业是最有可能受到影响的部门之一。本文提出了一种风险评估方法，以帮助地方层面的决策过程，解决影响河口边缘农业区的两个风险：干旱和土地期间河口咸水上游传播导致灌溉淡水不可用。与高潮和风暴潮相关的高水位淹没。对于每个风险，提出了定量后果描述符，以通过连续的后果-概率图来支持风险级别的确定和评估。该方法的适用性通过其对 Lezíria Grande de Vila Franca de Xira 的应用进行了讨论，位于塔霍河口（葡萄牙）。结果表明，该方法适用于支持风险负责人采取行动减轻风险。提供了针对所处理风险的风险控制措施示例。所提议方法的主要优势在于它可以灵活地适应当地条件并随时间更新，以及易于风险承担者应用。