The Water Retention Index: Using land use planning to manage water resources in Europe

Abstract

Appropriate land management can be an effective approach to improving water quantity regulation. There is, however, a need to identify both where measures are most needed and where they may be most effective. The water retention index (WRI) was developed with this goal in mind.The WRI is a composite indicator which takes into account parameters reflecting potential water retention in vegetation, water bodies, soil and underlying aquifers, as well as the influence of slope and artificially sealed areas. Three land management scenarios were simulated up to 2030 using the LUISA modeling platform: increasing grassland in upstream areas as well as afforestation in both upstream areas and riparian zones. The WRI was computed for all scenarios as well as a comparative "business-as-usual" baseline scenario. All scenarios showed an overall improvement of the index as compared to this baseline, with afforestation in upstream areas having the greatest effect. The WRI can provide useful insights into the current capacity of a landscape to regulate water as well as the effectiveness of possible remediation strategies applied at the European scale. The management of both the quality and the quantity of Europe's water resources remains a major concern, especially given the current and potential future rate of urbanization. This increased population pressure and higher degree of soil sealing can lead to a reduction in both condition and quantity of natural areas. This paper looks more specifically at the potential impacts on water quantity management over time.An indicator is presented which reflects the landscape's capacity to regulate water (i.e., intercept, retain and store the water flowing through it), and which can be used to assess the potential impacts of land use changes over time. De Groot, Wilson, and Boumans (2002) state that water regulation is the role of land cover in regulating runoff and river discharge. Several approaches have been taken to quantify water regulation, including using infiltration rate (Le Clec'h et al., 2016) and/or soil water storage capacity (Laterra, Orúe, & Booman, 2012; Smith, De Groot, & Bergkamp, 2006;TEEB, 2010) ologies, however, are data-intensive and/or require specific models to be used. Some studies have already looked at more comprehensive, less data-intensive ways of estimating water retention or regulation capacity, both for smaller study areas (Šatalová & Kenderessy, 2017) and at --------------------------------------------------------------------------------------------------------------------------------This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

European environment policy for the circular economy: Implications for business and industry stakeholders

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Perspectives of land evaluation of floodplains under conditions of aridification based on the assessment of ecosystem services

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