Conference Agenda

Restoration of degraded rangelands through rainwater harvesting (RWH) has emerged as a key intervention in arid and semi-arid regions for sustaining and improving their productivity and the ecosystem services they support. We carry out a cost-benefit analysis (CBA) to assess the economic viability of implementing contour ridges as an in-situ RWH technique to restore the degraded rangelands in Jordan, a country characterized by extensive pastoral areas and significant water deficiency expected to be worsened through climate change. We consider the benefits derived from changes in three key ecosystem services, namely forage production, water availability, and soil erosion prevention, and the costs for implementing and maintaining contour ridges. We employed the Global Range (G-Range) model to quantify the increase in forage production and the Soil and Water Assessment Tool (SWAT) model to estimate the increase in water availability and the improvement of soil erosion prevention. The CBA was conducted across five distinct classes within the rangeland, differentiated by average annual rainfall, land slope, and soil organic carbon (SOC), which allows us to cover 69% of Jordanian rangelands. We find Positive Net Present Values (NPVs) for all five classes across three discount rates considered, indicating that the implementation of contour ridges is economically viable throughout the rangelands. We also highlight key limitations that may arise when implementing contour ridges in practice and discuss further research needed to optimize restoration efforts and promote sustainable ecosystem management.

Climate change and population growth exacerbate water scarcity in the Mediterranean region, threatening food security. A variety of modeling approaches that embed water into a Computable General Equilibrium (CGE) framework is available. However, only a few studies incorporate non-conventional, alternative water sources (e.g., desalination, treated, brackish) into economic analyses. Alternative water sources vary in energy and capital intensity and, therefore, in costs and externalities. We present the first study to introduce alternative water sources to a global CGE model. We also investigate the role of novel technologies of controlled-environment agriculture (CEA) that save water and land at the cost of higher energy intensity than traditional agriculture practices. The results show that the availability of alternative water sources increases the domestic production of grain crops in the North Mediterranean region. The countries that gain the most from CEA technologies are those with a higher share of irrigation and skilled labor. The results reflect the significant value of alternative water sources and CEA technologies to the agricultural sector. The outcomes also indicate that alternative water practices and CEA may bring about a positive trajectory in food security and the global economy, with a negligible effect on energy use.

Water resources present a classic tragedy of the commons that is of increasing relevance as a result of climate change. This paper provides evidence of the impacts of property rights institutions on the efficiency of water markets. We study the role of local irrigators organizations in the operation of water markets. Our analysis is based on a novel dataset that integrates administrative records, hydrological measures, geographic information, and satellite imagery. We develop a novel misallocation test, which suggests that these organizations reduce misallocation caused by the natural advantage of upstream users to over-extract. We show that efficiency is a result of both redistribution and individual adaptation: downstream farmers increase their water consumption and agricultural yield. Large farms extend their growing season, adopt more efficient irrigation technologies, and overall gather more benefits from this institution. Upstream farmers reduce their water consumption, but their productive outcomes do not display changes. We also document increases in river streamflow during the irrigation season, and reductions in reclamations. Our results provide micro-evidence of the consequences of effective governance for both allocative efficiency and equity.

We set up a dynamic two-period model in which farmers decide on both land-use and water-use, while extracting from a common groundwater resource. We compute the Nash feedback equilibrium and the common property optimal solution, for symmetric and heterogeneous players. We first study the case where only water is a decision variable and then the case where water and land-use are decision variables, characterizing the intensive and extensive margin. We show that under Nash, more water is extracted than optimal, but more importantly, greater surfaces are irrigated and more water is extracted in the first period than in the second, in contrast to the optimal policy, showing the effect of strategic competition. We show in an example how regulating land-use may be a Pareto-improving policy and that not regulating it increases the difference between optimal and Nash gains, reducing the Gisser-Sanchez effect.