Agriculture is one of the largest economic sectors in Mpumalanga, producing 15% of total output in South Africa (South Africa Yearbook, 2001/02). The growing demand for agricultural products is an important driver of the agricultural sector. Products include sugar cane, sunflower seed, sorghum, potatoes, onions, cotton and maize.

Agricultural production in Mpumalanga ranges widely from summer cereals and legumes in the highveld region to subtropical and citrus fruit and sugar in the lowveld. For the most part, dry farming land is utilised in agricultural production, but there are extensive irrigation activities in the Loskop area near Groblersdal and in the lowveld area adjacent to the Crocodile and Komati Rivers (MII, 2003).

Storage dams in the lowveld rivers will step up the production of sugar, subtropical fruit and vegetables, and the reopened Maputo harbour is encouraging exports of agricultural crops. Added to this, the domestic demand for food crops will be stimulated by the continuous vigorous growth rate in the province. Overall there is considerable potential for increased agro-processing in Mpumalanga (MII, 2003), but increased agricultural production may be constrained by the limited water resources in some of the water-stressed catchments (such as the Inkomati catchment).

Water is a constraint for agricultural production as is the impact that such agricultural activities are having on the environment, in particular impact that irrigated agricultural practices are having on water resources. Furthermore, such agricultural activities have a impact on biodiversity due to the vast clearing and loss of vegetation, with a resultant loss of biodiversity, especially the loss of underground bulbous plants found in biodiversity rich grasslands. The clearing of land also results in the loss of habitats and ecosystems, and the associated environmental services  that such ecosystems provide (i.e. erosion control, groundwater recharge, etc.). The clearing of natural vegetation and transformation of ecosystems also results in the creation of pathways for alien species invasion.  Apart from the obvious disturbance caused by the clearing of land for agricultural production, other environmental impacts as a result of agriculture activities, also include:

• Deterioration of soil quality from increased leaching of nutrients;
• Water quality can be adversely affected by siltation and by human and agricultural wastes;
• Contamination of surface and groundwater from fertilizer and pesticide run-off.