全球变化知识资源中心

Agroecosystems are important for food production and conservation of biodiversity while continuing to provide several ecosystem services within the landscape. Despite their economic and ecological benefits, most agroecosystems in Tanzania are degraded at alarming rates. Rapid increase of human population and unprecedented impacts of climate change have influenced depletion of natural resource base within agroecosystem in recent decades compared to what communities have experienced before. Increased food demands owing to population increase have increased pressure on exploitation of land resources including water. Cultivation area and irrigation water demands have increased steadily in the last six decades. Nevertheless, approaches used for water supply have not been improved; thus, water use efficiency in most irrigation schemes is quite poor. Conversely, climate smart agricultural practices are practiced less in Tanzania. There is poor adoption of recommended adaptation among smallholder farmers due to several socioeconomic reasons. One of the key objectives of climate smart agriculture is to improve bio-geochemical interactions within landscape and decrease competition of natural resources between humans and other component of agroecosystems. This underscores the assumptions that most cropping systems in Tanzania are not managed sustainably. Moreover, comprehensive assessment of hydrological dynamics within smallholder farming in Tanzania is highly lacking. Therefore, actual causes and extent of water resources depletion are largely unknown among stakeholders. In most tropical landscapes, water resources degradation is influenced by interaction of both anthropogenic and biophysical factors operating at different times and space scales. As the capacity of water-supplying sources continues to decline, Tanzania needs profound changes in agricultural production systems in order to nourish the growing human population. This calls for strategic approaches that have wider adaptability. A literature survey study with the following objectives was conducted (i) to assess current state of agricultural water use and irrigation activities in Tanzania and (ii) to determine major constraints for sustainable water management and identify appropriate adaptation measures for their improvement across diverse cropping systems.