Sustainable land use and water management on reducing soil erosion & improving soil and water quality
The applications of nuclear techniques have significantly achieved social and economical benefits when soil erosion is reduced, as observed in the recently completed regional project RAS5039 in East Asia and the Pacific region on developing sustainable land and water management strategies using fallout radionuclides for reducing soil erosion and improving soil and water quality. Ten countries participated in this project: BGD, CPR, IND, INS, MAL, PAK, PHI, SRL, THA and VIE.
Some of the achievements include: Bangladesh and Pakistan introduced short-duration nitrogen-fixing mung bean into the commonly grown rice-wheat-cropping systems, resulting in increasing N inputs and potential economic benefit (savings of about 20% in N fertilizers). The use of nitrogen-15 isotopes helped to estimate biological nitrogen fixation and the nitrogen contribution from the legume to the system.
Also, China, Indonesia, Malaysia, Philippines, Sri Lanka, and Thailand were able to develop management practices for the combined use of organic residues and chemical fertilizers for improving soil fertility status and sustainable soil productivity in rice-based cropping systems. The results of the studies were utilized to formulate recommendations on improved agronomical practices, which were disseminated and transferred to the farmers and producers. Using cesium-137 technique, soil erosion and sedimentation rates were generated easily.
In addition, reliable quantitative data on spatial soil redistribution in the landscape and pesticide contamination in soil, water and plant were readily estimated.