The Southern African Millennium Ecosystem Assessment (SAf MA) evaluated the relationships between ecosystem services and human well-being at multiple scales, ranging from local through to sub-continental. Trends in ecosystem services (fresh water, food, fuel-wood, cultural and biodiversity) over the period 1990-2000 were mixed across scales. Freshwater resources appear strained across the continent with large numbers of people not securing adequate supplies, especially of good quality water. This translates to high infant mortality patterns across the region. In some areas, the use of water resources for irrigated agriculture and urban-industrial expansion is taking place at considerable cost to the quality and quantity of freshwater available to ecosystems and for domestic use. Staple cereal production across the region has increased but was outstripped by population growth while protein malnutrition is on the rise. The much-anticipated wood-fuel crisis on the subcontinent has not materialized but some areas are experiencing shortages while numerous others remain vulnerable. Cultural benefits of biodiversity are considerable, though hard to quantify or track over time. Biodiversity resources remain at reasonable levels, but are declining faster than reflected in species extinction rates and appear highly sensitive to land-use decisions. The SAf MA sub-global assessment provided an opportunity to experiment with innovative ways to assess ecosystem services including the use of supply-demand surfaces, service sources and sink areas, priority areas for service provision, service 'hotspots' and trade-off assessments.

No abstract

No abstract

Globally, there are social, economic and environmental challenges related to sustainable development; these challenges include climate change, the need to feed a rapidly increasing population, high rates of poverty and environmental degradation. These challenges have forced us to rethink the way in which development takes place, resulting in the emergence of the concept of a ‘green economy’. A green economy results in improved human well-being and social equity, while significantly reducing risks to the environment. It is based on principles which integrate social, economic and environmental considerations. South Africa has adopted the principle of green economic growth, and agriculture is one of the sectors that will drive this growth. Agriculture could address some of the sustainable development problems, but there are challenges related to resource availability, environmental impacts of agriculture and climate change. For agriculture to support a green economy it has to be productive, contribute to economic growth and not undermine the environment, social and cultural systems. The information base and policies required to support a green economy in general, and/or an agriculture-supported green economy have not yet been developed, as the green economy is an emerging concept in South Africa as well as globally. The generation of such information requires analysis and synthesis of green economy principles and agricultural imperatives into generic principles and practices for facilitating agriculture’s contribution to the green economy. In this paper, we conduct this analysis and synthesis and highlight the defining aspects of an agricultural green economy.

Boosting the productivity of smallholder farming systems continues to be a major need in Africa. Challenges relating to how to improve irrigation are multi‐factor and multisectoral, and they involve a broad range of actors who must interact to reach decisions collectively. We provide a systematic reflection on findings from the research project EAU4Food, which adopted a transdisciplinary approach to irrigation for food security research in five case studies in Ethiopia, Mali, Mozambique, South Africa and Tunisia. The EAU4Food experiences emphasize that actual innovation at irrigated smallholder farm level remains limited without sufficient improvement of the enabling environment and taking note of the wider political economy environment. Most project partners felt at the end of the project that the transdisciplinary approach has indeed enriched the research process by providing different and multiple insights from actors outside the academic field. Local capacity to facilitate transdisciplinary research and engagement with practitioners was developed and could support the continuation and scaling up of the approach. Future projects may benefit from a longer time frame to allow for deeper exchange of lessons learned among different stakeholders and a dedicated effort to analyse possible improvements of the enabling environment from the beginning of the research process. © 2020 The Authors. Irrigation and Drainage published by John Wiley & Sons Ltd on behalf of International Commission for Irrigation and Drainage

No abstract

No abstract

Agriculture in developing countries will have to transform and increase production by an estimated 70% in order to meet demands by 2050. Although well‐managed commercial farms offer little manoeuvring space for increasing agricultural water productivity, smallholder farms usually operate at low input costs and therefore provide ample opportunities to reduce the potential yield gap through agricultural intensification. The aim of this paper is to analyse and compare yields and water productivities obtained in field and modelling experiments in Ethiopia (maize, garlic, onion), South Africa (tomato) and Tunisia (tomato, potato, wheat). Innovative agricultural practices were introduced on smallholder farms: irrigation scheduling and NPS Zn fertilization in Ethiopia; high‐yielding cultivar, drip irrigation, mulching and organic amendments in South Africa; and crop water modelling in Tunisia. In general, crop yields increased up to eight times with innovative practices compared to current conventional farming practices. Crop water productivities were fairly stable within the same experiments, but increased with innovations, indicating that intensive farming can be more environmentally sustainable than conventional farming. Intensive farming systems in a resource‐rich environment (high radiation levels, relatively fertile, deep and well‐drained soils), combined with technology transfer and capacity building could be seen as viable strategies to secure food for smallholders and communities in African rural areas, as well as to improve water utilization in water‐scarce catchments. Copyright © 2018 John Wiley & Sons, Ltd.