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Water harvesting techniques (WHTs) are important climate change adaptation measures to better manage rainwater for domestic and agricultural purposes, but which WHT to plan where is subject to sustainability considerations. Moreover, suitability of different WHTs varies from one location to another, depending on physical and socio-economic conditions. This study aimed to identify suitable sites for WHTs taking into account stakeholders’ sustainability criteria. In a participatory assessment framework, Geographic Information Systems and the “Simple Multi-Attribute Rating Technique” were combined to generate suitability maps and to guide sustainable WHTs investments. Steps included the calculation of a sustainability index for a set of traditional and newly introduced WHTs from the perspective of two stakeholder groups, farmers and decision-makers, and its integration with layers of biophysical constraints. An application of the framework in the Oum Zessar watershed, southeast Tunisia, shows that traditional techniques are the most suitable and sustainable for farmers and fall within the highly suitable class in 76.4% of the total area, while decision-makers prefer innovative techniques that are highly suitable in 80.4% of the watershed. The framework offers a scalable transparent process for knowledge integration in support of WHT investment decisions that can be adapted to other dryland areas.

This paper analyzes the complex relationships of factors influencing residue biomass management in cereal–sheep production systems in semi-arid areas of Tunisia. The Bayesian belief network (BBN) methodology was applied to identify factors enabling the better management of crop residue (CR) at the farm level. Data were collected from 152 farms located in the governorate of Siliana in north-west Tunisia. After designing the complex interactions between different variables that have an influence on the allocation of CR, BBN was also applied as a predictive model by inserting evidence conditional probabilities on the quantity of CR left on the soil and simulating the incurrent changes in the probability state of the remaining network variables. The results show that around 70% of farmers in our sample retain an overall quantity of CR lower than 200 kg/ha. The share of livestock income, livestock herds, cost of livestock feed, and off-farm income are all factors that have a strong influence on residue biomass management.

The objective of this paper is to analyse the olive oil value chain (OVC) in the Governorate of Medenine (south-east of Tunisia) and the relationships between its main operators for an effective involvement and better performance and resilience of olive sector. Based on semi structured interviews and participatory multi-stakeholders’ workshops, OVC has been analysed and described. MACTOR approach has been applied to establish linkages among chain operators and activities in a partnership approach. Innovative interventions were proposed to strengthen farmers’ organizations to increase profitability of OVC. Empirical findings suggest that public-private-civil society partnerships are essential for the development of pro-poor approaches for uncovering technological and institutional innovations which may involve more inclusive olive oil value chains. The underpinnings of our argument will be of interest and value to both development practitioners and the research community engaged within Tunisia, and the wider region more generally, on initiatives aimed at fostering effective, inclusive and contextually relevant processes for agricultural innovation. ---- , , ,.

People living in arid and semi-arid areas with highly variable rainfall and unforeseeable periods of droughts or floods are severely affected by water shortages and often have insecure livelihoods. The construction of dams in wadies to harvest rainwater from small watersheds and to induce artificial groundwater recharge is one of the solutions available to overcome water shortages in the Western Desert of Iraq. The success of rainwater harvesting (RWH) systems depends heavily on their technical design and on the identification of suitable sites. Our main goal was to identify suitable sites for dams using a suitability model created with ModelBuilder in ArcGIS 10.2. The model combined various biophysical factors: slope, runoff depth, land use, soil texture, and stream order. The suitability map should be useful to hydrologists, decision-makers, and planners for quickly identifying areas with the highest potential for harvesting rainwater. The implementation of this method should also support any policy shifts towards the widespread adoption of RWH. Keywords: GIS, Rainwater harvesting, Iraq's western desert, Suitability map

Despite broad interest in use of water harvesting techniques (WHTs) to reduce pressure on natural resources in arid zones, few ex post assessments are available on how WHTs impact livelihood sustainability. This paper assesses the impact of WHTs on the livelihood conditions of inhabitants in the Oum Zessar watershed in south-east Tunisia. We used an integrated impact assessment (IIA) framework incorporating extended cost–benefit analysis (ECBA) and the sustainable livelihoods approach (SLA). The former internalizes environmental impacts while the latter enables assessment of the contributions of WHTs to rural livelihoods in the watershed. We began by using ECBA to estimate the profitability of investments in WHTs. We then scaled up our impact perspective from the local level to the watershed level using SLA based on survey data from beneficiary households upstream, midstream and downstream. Our goal was to better understand and evaluate changes in livelihoods and associated environmental effects. We focused on the links between cost–benefit of WHTs and sustainable livelihoods, looking in particular at the capitals that connect the two. Our ECBA results suggest that WHT techniques did benefit the local population at both the private and the social level (IRR > 20%; NPV > 2000 TD/ha). Sensitivity analysis confirmed this result. SLA findings point to a central role of social capital in promoting sustainable livelihoods, followed by physical capital enhanced by WHTs construction, especially in the upstream and downstream segments of the watershed. Recommendations were derived from these outcomes for more integrated watershed management policy.

This paper applies multiple analytical and empirical methods to evaluate the sustainability impacts of climate change and prospective adaptation measures based on water harvesting techniques (WHTs) at the regional level. We developed a sustainability composite index (SCI) for an arid zone in Tunisia, specifically the south-eastern Province of Medenine. To quantify the SCI, a static computable general equilibrium model (CGE) was adapted to the region. To provide a database for the CGE model, we built a regional social accounting matrix (RSAM). A bottom-up approach was applied to build a regional supply and use matrix for the agricultural sector incorporating natural resources (land and water) as intermediate inputs. Our regional SAM included ten production factors, 18 production sectors producing 22 goods and services, two household types (urban and rural), one representative enterprise, two public sectors (central and regional administration), taxes accounts, two capital accounts (savings/investment and changes in stocks), the rest of the world and the rest of the country. We used the RSAM to calculate the regional GDP. Two simulations were run, focused on the 2030 time horizon from the baseline year of 2006: (i) declining natural capital due to the effects of climate change and (ii) implementation of a regional climate change adaptation strategy based on water harvesting technologies (WHTs). Scenario identification drew on previous research and was performed in close collaboration with regional stakeholders. Based on the outputs of the CGE model, the impacts of the two scenarios on the main regional economic indicators were analysed. Using multi-criteria analysis (MCA), we calculated an aggregated SCI for regional development. Results suggest that implementation of the regional climate change adaptation strategy would have positive impacts, but would be insufficient to maintain the SCI at its current level.

The need to enhance sustainable development of land use is more urgent than ever; specifically in developing countries where poverty and land degradation are often interlinked. To promote a common understanding of land use problems by experts, stakeholders and decision makers, it is essential to understand the system characteristics, including the complex feedbacks between drivers and impacts. To enhance sustainable development, appropriate policies need to be identified. In this paper, we analysed and compared seven case studies in Kenya, Mali, Tunisia, China, India, Indonesia and Brazil, representing different biophysical and socio-economic conditions and challenges. We analysed Driver Pressure State Impact Response (DPSIR) story lines of the land use problems, policy priorities and value trade-offs as identified by stakeholders and experts in National Policy Forums. Important drivers of land use change impacting main land use problems among the case studies were economic growth, technological development, immigration and agricultural intensification, in addition to existing policies. Of the latter the most important were related to domestic support through various forms of subsidies or access to credit, land tenure polices and liberalization policies. In the policy prioritization, the value trade-offs made by the National Policy Forums emphasize the environment rather than increased economic production. It is recognized that the environment needs to be improved to maintain and improve economic production in the long term, both in agriculture and in other sectors.

Environmental threats and progressive degradation of natural resources are considered critical impediments to sustainable development. This paper reports on a participatory impact assessment of alternative soil and water conservation (SWC) scenarios in the Oum Zessar watershed, Tunisia. The first objective was to assess the impact of three SWC scenarios on key social, economic and environmental land use functions. The second objective was to test and evaluate the applicability of the 'Framework for Participatory Impact Assessment (FoPIA)' for assessing scenario impacts in the context of a developing country, in this case Tunisia. The assessed scenarios included: the originally planned SWC policy implementation at 85 % coverage of arable land of the watershed, the current implementation (70 %), and a hypothetical expansion of SWC measures to the entire watershed (100 %). Our results suggest that implementation of the SWC policy at 100 % coverage of arable land achieves the maximum socioeconomic benefit. However, if stakeholders' preferences regarding land use functions are taken into account, and considering the fact that the implementation of SWC measures also implies some negative changes to traditional landscapes and the natural system, SWC implementation at 85 % coverage of arable land might be preferable. The FoPIA approved to be a useful tool for conducting a holistic sustainability impact assessment of SWC scenarios and for studying the most intriguing sustainability problems while providing possible recommendations towards sustainable development. We conclude that participatory impact assessment contributes to an enhanced regional understanding of key linkages between policy effects and sustainable development, which provides the foundation for improved policy decision making.