Water and Agriculture
At a time of mounting
population pressures, environmental declines, and a growing demand for water,
resolving the water resource conundrum will require concerted political will
and action at all levels. Although the challenges are vast, experts agree that
it is indeed possible to create a future in which water resources and
agriculture represent forces of resilience, rather than vulnerability.
Understanding the hydrological cycle through soil science
CONTRIBUTIONS BY SOIL SCIENTISTS TOWARD THE UNDERSTANDING OF WATER ISSUES ARE QUITE UNIQUE, RESULTING FROM THEIR SPECIFIC KNOWLEDGE ABOUT SOILS AND HOW SOILS RESPOND TO WATER. SUSTAINABILITY IN AGRICULTURE IS BASED ON A SOUND KNOWLEDGE OF THE INTERACTION BETWEEN THE SOIL (PHYSICS, CHEMISTRY, BIOLOGY) AND WATER (QUANTITY AND QUALITY), AND HOW THIS INTERACTION IMPACTS ON THE ENVIRONMENT.
This complexity, and the knowledge about how agriculture impacts on the natural environment, are normally best described through hydrological modelling. Agriculture, as an economic sector, is the fourth most important water user under the South African water law. The Department of Soil Science is involved with various aspects of water and hydrological research that generally includes farm scale to catchment scale research. Monitoring is done of soil water content, soil chemical changes, weather, boreholes and land use change. Soils are classified and landscapes are mapped as a basis of understanding all the processes involved. The use of Geographical Information Systems forms an integral part of the research.
It is of the utmost importance to include all processes and practices in a framework modelling approach as any change in any part of this process will eventually have an effect on water quality and quantity of the river and environment in general.
The research of the Department of Soil Science focuses on:
- sustainable water use to produce crops and to increase the water use efficiencies of irrigation practices,
- investigating the contribution and influence of agriculture on the pollution of our river systems,
- projects that develop, test and use hydrological and water use models, which apply from farm scale to catchment scale, and
- projects that map the diversity in our landscapes that also impact on water.
Present research projects include wetland research, the effect of land use change on water quality in our rivers, and the development of criteria to measure and manage water adequately. This is done in three Water Research Commission projects currently conducted at the department. Most of this research is conducted in the Berg River catchment and include various collaborators.