Outline of the project "Comprehensive Studies on Sustainable Agricultural Systems in Northeast Thailand"; Hydrological and geochemical behavior of saline groundwater in Phra Yun, Northeast Thailand; Classification of salt affected areas using remote sensing and GIS; Location and function of the reservoirs in Ban Nong Saeng, Northeast Thailand; Land suitability analysis concerning water resource and soil property; A farmer participatory approach to development of a research agenda for water managment priorities in Nong Saeng village, Khon Kaen Province, Thailand; Utilization of organic resources in cassava farming in Northeast Thailand;; Nitrogen cycles and nutrient balancein agro-ecosystems in Northeast Thailand; Colleting and evaluating wild relatives of sugarcane as breeding materials of new type sugarcane cultivars of cattle feed in Northeast Thailand; Evaluation of sustainability of sugarcane production in Thailand based on nitrogen fixation, efficiency of nitrogen fertilizer and flow of organic matter; Role of native ruminants in establishment of sustainability agricultural systems in Northeast Thailand; Sugarcane stalk as a roughage for dairy cattle; Energy and nitrogen metabolism in Holstein crossbred by cows given Ruzi grass hay with different levels of soybean meal; Energy and nitrogen metabolism in lactating cows fed with rice straw and corn silage; A study on nutritive values of tropical forages (1) Ruzi grass (Brachiaria ruziziensis), (2) Verano stylo (Stylosanthes hamata cv. Verano); A study on nutritive values of forage crops (3) Purple Guinea grass (Panicum maximum cv. TD58), (4) Thapra stylo legume (Stylosanthes guianensis CIATI84); Present situations and improvement of upland farm management: Focusing on sugarcane production; Prevalent agricultural practices and soil fertility in sugarcane cropping in Northeast Thailand; Alternative tillage system for soil conservation, enhancement of crop growth and increasing working efficiency; Development of a sustainable lowland cropping system in Northeast Thailand; Development of no-tillage direct seedling cultivation of rice; Crop Management of direct seeded rice; Economy of direct seeding of rice in Northeast Thailand; and its future direction; Quality evaluation of Khao Dawk Mali 105, an aromatic rive variety of Northeast Thailand; Vegetable production using energy-saving hydroponic system in Khon Kaen; Development and evaluation of bagasse silage for cattle feed; Processing and utilization of small round-bale wrapped silage made from tropical forages; Feed management and significance of storage of roughage for dry season in dairy farming; Eco-physiological characteristics of Erianthus spp. and yield abilities of three forages under conditions of cattle feces application; Effects of dry cattle feces application on soil chemical properties in upland fields in Khon Kaen; Nitrogen cycles in current and improved crop/animal integrated systems in Northeast Thailand.