BRGM (French Geological Survey), Water Department, 1039 rue de Pinville, 34000 Montpellier, France.
J Environ Manage. 2013 Oct 15;128:62-74. doi: 10.1016/j.jenvman.2013.04.058. Epub 2013 May 28.
In Europe, 30% of groundwater bodies are considered to be at risk of not achieving the Water Framework Directive (WFD) 'good status' objective by 2015, and 45% are in doubt of doing so. Diffuse agricultural pollution is one of the main pressures affecting groundwater bodies. To tackle this problem, the WFD requires Member States to design and implement cost-effective programs of measures to achieve the 'good status' objective by 2027 at the latest. Hitherto, action plans have mainly consisted of promoting the adoption of Agri-Environmental Schemes (AES). This raises a number of questions concerning the effectiveness of such schemes for improving groundwater status, and the economic implications of their implementation. We propose a hydro-economic model that combines a hydrogeological model to simulate groundwater quality evolution with agronomic and economic components to assess the expected costs, effectiveness, and benefits of AES implementation. This hydro-economic model can be used to identify cost-effective AES combinations at groundwater-body scale and to show the benefits to be expected from the resulting improvement in groundwater quality. The model is applied here to a rural area encompassing the Hesbaye aquifer, a large chalk aquifer which supplies about 230,000 inhabitants in the city of Liege (Belgium) and is severely contaminated by agricultural nitrates. We show that the time frame within which improvements in the Hesbaye groundwater quality can be expected may be much longer than that required by the WFD. Current WFD programs based on AES may be inappropriate for achieving the 'good status' objective in the most productive agricultural areas, in particular because these schemes are insufficiently attractive. Achieving 'good status' by 2027 would demand a substantial change in the design of AES, involving costs that may not be offset by benefits in the case of chalk aquifers with long renewal times.
在欧洲，有 30%的地下水体被认为到 2015 年无法实现《水框架指令》（WFD）的“良好状态”目标，而有 45%的地下水体对此表示怀疑。农业面源污染是影响地下水体的主要压力之一。为了解决这个问题，WFD 要求成员国设计和实施具有成本效益的措施方案，最迟在 2027 年实现“良好状态”目标。迄今为止，行动计划主要包括推广采用农业环境计划（AES）。这引发了一些关于这些计划对于改善地下水状况的有效性的问题，以及其实施的经济影响。我们提出了一个水经济模型，该模型将一个水文地质模型与农业和经济组件相结合，以评估 AES 实施的预期成本、有效性和收益。该水经济模型可用于在地下水体尺度上识别具有成本效益的 AES 组合，并展示从地下水质量改善中预期获得的收益。该模型应用于包含 Hesbaye 含水层的农村地区，该含水层是一个大型白垩含水层，为比利时列日市（比利时）约 23 万居民提供供水，并且受到农业硝酸盐的严重污染。我们表明，预计 Hesbaye 地下水质量改善的时间框架可能比 WFD 要求的时间长得多。目前基于 AES 的 WFD 计划可能不适合在最具生产力的农业地区实现“良好状态”目标，特别是因为这些计划不够吸引人。在白垩含水层更新时间较长的情况下，要在 2027 年达到“良好状态”可能需要对 AES 的设计进行重大改变，这可能会导致成本增加，而收益却无法抵消。
