Integrated, resilient and inclusive land and water use

The uses of water and land are intrinsically linked, and their management requires integrated nexus approaches.  Changes in land use, such as deforestation, may have profound effects on water resources downstream. Soil conservation measures - land-based interventions focused on rainfall - have direct implications for the natural vegetation and food or fuel crops. Food production requires large areas of land and consumes huge amounts of water, thereby affecting terrestrial and aquatic ecosystems. Urbanization in densely populated delta regions increases demand for high-quality freshwater resources, while at the same time often worsening pollution and loss of natural and agricultural land.

Because of these interdependencies, policies and interventions in one domain may have unintended knock-on effects in other domains. For example, policies to encourage clean energy may lead to increased use of land and water for biofuels, or more hydropower dams that disrupt river flows. Energy subsidies that reduce the cost of pumping groundwater, which supports its productive use and enhances rural incomes, may also lead to overexploitation and groundwater level decline. Interventions in the landscape to encourage more efficient and productive agriculture to provide a livelihood to a growing population may lead to the loss of wetlands, water pollution, soil degradation and increased greenhouse gas emissions.

People living downstream may suffer from the negative consequences of upstream land and water use.  For example, interventions to enhance efficient water use and increase crop production may worsen inequality and water shortages downstream. Protection of wetlands in national parks may attract tourism and provide income to some, while at the same time removing local populations’ access to the land and its ecosystem services.

Exploring and quantifying these trade-offs contributes to integrated, resilient and inclusive land and water use. However, because of the complex interplay of bio-physical and social-political factors, there is a high level of uncertainty about how trends and interventions in land and water and global change will play out for diverse groups in society. This calls for an open critical mind and participatory adaptive planning  

Our research focus areas

• Integrated and participatory nexus modelling with stakeholders in hotspots as a means towards conflict resolution and identification of trade-offs and synergies between water, food, energy and the environment. Using a range of approaches from qualitative systems mapping to quantitative modelling, we enhance knowledge on complex water-food-energy systems at multiple scales with the goal of improving integrated resources management and policymaking. Studies in this field increasingly consider the roles of a wide range of stakeholder groups through local networks. Research ranges from fundamental studies into systems behaviour to applied case-study based research. Recent projects include NEXOGENESIS, ONEPLanET, WEF Tools and SIM4NEXUS.
• Innovative water accounting approaches to assess land and water use to enable informed decision-making with relevant stakeholders
• Adaptive and transformative pathways planning
• Farmer-led irrigation
• Nature-based solutions to support economic development and inclusive ecosystem approaches in managed land-water systems.

The theme of integrated, resilient and inclusive land and water use emphasizes sustainability and social justice. This means that the needs, rights and claims of different stakeholders should be considered when developing policies and institutions for land and water management. It also means considering the different values, trade-offs and synergies involved in allocating and sharing land and water resources among different societal actors. 

Whereas land can best be defined in spatial terms, water is more aptly characterised in temporal terms. Water scarcity is often a temporal phenomenon. Storage helps to buffer against temporal fluctuations in the availability of water, but storage solutions are inevitable spatially defined. Resilient water systems thus include terrestrial stores that are natural, human-made or human-influenced. Water stored in sand rivers illustrate how combining natural (green) storage of the alluvial aquifer in the riverbed and built (grey) infrastructure of so-called sand dams can greatly enhance the natural storage capacity. This is demonstrated for example in Kenya and Zimbabwe, where local farmers have developed several innovative mechanisms to finance and exploit sand rivers. IHE Delft and local partners documented the resilient and inclusive land and water use in alluvial aquifers in sub-Saharan Africa to draw lessons for use in other areas.