In North Africa, particularly in Tunisia, the growing population and shifting consumption patterns have led to excessive use of agricultural chemical inputs and environmental degradation on one hand, and to the increase of solid waste production, on the other hand. To address this, sustainable agricultural practices are crucial, especially given the looming threat of climate change, illustrated by long drought periods in the last two years. To mitigate the effects of climate change, several levers can be proposed. In this project, we propose to evaluate the use of biochar. Indeed, biochar, derived from organic waste carbonization, has emerged as a sustainable solution to improve soil quality, remediate soil pollution, and mitigate waste-associated emissions. Tunisia, being a significant producer of olive oil and dates, has ample agricultural and agro-industrial waste suitable for biochar production, offering a promising avenue for waste management and soil quality improvement. Soil degradation in Tunisia's arid and semi-arid regions presents a significant challenge, exacerbated by human activities and agricultural practices. Biochar holds promise in restoring soil fertility, enhancing water and nutrient retention, and mitigating nutrient leaching. However, to optimize biochar application, it is essential to understand its properties and how they interact with soil dynamics and contaminants. This includes studying its impact on soil microbiology, physical properties, and plant growth, especially in saline and sloping soils prevalent in Tunisia. The aim of this project is therefore to set up a multidisciplinary team of young researchers studying the evaluation of the possibilities of using biochar made from different types of local agricultural residues, to optimize various contaminants retention while improving agronomic and environmental qualities, taking into account the specific constraints of the southern Mediterranean in local agriculture practices and the management of agricultural residues within the framework of a circular economy. The project proposes six complementary tasks: (i) biochar production and physicochemical characterization, (ii) assessment of its impact on soil microbiology, (iii) evaluation of soil physical properties post-biochar application, (iv) examining its effect on local plant growth, (v) impact of biochar on some contaminants removal, (vi) assessing its agronomic performance in saline and sloping soils. Furthermore, capacity building through collective and specific training for researchers and students will be prioritized, ensuring knowledge dissemination and skill development in ecological engineering. Through rigorous research and knowledge sharing and through workshops and seminars organized by senior IRD researchers and several partners involved in the project, the project aims to foster sustainable agricultural practices and enhance soil quality in Tunisia.

Biochar, water use efficiency