Improving efficiency of water use in rice-based cropping systems using permanent raised beds

Abstract

A major challenge for the next 20 years is to develop genetic and agronomic solutions to combat water shortages for rice production and to develop ecosystems that better match crop growth with water supply. Experiments were conducted in northern Queensland, Australia (1989–1992) and eastern Indonesia (1993–1999) to develop a cropping system based on raised beds and saturated soil culture (SSC), whereby rice could successfully be grown in rotation with several field crops. Advantages of the SSC system include improved efficiencies of water use, energy savings, enhanced timeliness of field operations and reduced soil compaction. The northern Queensland studies indicated that double cropping rice and field crops on permanent raised beds provides additional synergistic and logistic benefits over those found in the traditional rice/fallow system. Subsequent experiments in West Timor found that various crops, as well as rice, can be grown on raised beds during the wet season, thus overcoming the problem of waterlogging. Moreover, if raised beds were constructed before the wet season in lowland areas, crops could be sown at the onset of the wet season, thus avoiding end-of-season drought and permitting significant increases in crop yields. Reforesting of eroded upland cropping areas with perennial tree species was also possible, provided the intensive lowland production met the subsistence farmers’ basic food and/or cash crop requirements. By increasing the probability of year-round crop production, this system, overall, can help enhance food security for South-East Asian subsistence farmers.