STUDIES ON THE LAND IMPROVEMENT IN THE SALINE SOIL AREA

1. 1996年，我们与岩手大学农学系和吉林农业大学的科学家在吉林省洮南市西部选择了一个典型的盐渍土试验区，进行了实地调查。土壤理化分析结果表明，土壤容重1.6 ~ 1.7，固相含量60%，pH值9 ~ 10，土壤呈高碱性，表层积盐以碳酸钠为主，质地为粉质粘土或重粘土。稻田水质pH值和电导率没有问题，但水温较低. 1997年和1998年在吉林省大安市神江子村进行了三个试验：草地恢复试验：过度放牧是造成该地区草地退化的重要因素之一。为此，以650公顷天然草地为研究对象，研究了草地暂时禁牧的效果。从对照区来看，在恢复植被和提高草地生产力方面有很大的效果。盐碱地改良试验：在玉米栽培条件下，研究了土壤调理剂用量与作物生长的关系。覆膜与施用硫酸铝或石膏相结合，即使在不适宜种植的地区，也能大幅度提高玉米产量。改良盐碱地稻田试验：研究了灌溉对盐分淋溶、水稻生长和产量的影响。当使用从地下80米抽上来的地下水时，水稻产量提高到6,000公斤/公顷。在地下水充足的地区，水稻种植和排水渠的装备，可以预期高生产力。

1. In 1996, we, the scientists of the Agronomy Department of Iwate University and Jilin Agricultural University, chose an experimental region of typical saline-soil at the western area of Taonan city, Jilin province, and conducted the field investigation. As the results of physical and chemical analyses of the soil, bulk density was 1.6 - 1.7, percentage of solid phase was 60%, soil showed high alkalinity at 9 - 10 pH, and the salts accumulated in the topsoil was mainly sodium carbonate, the soil texture was silty clay or heavy clay. There was no problem in water quality including pH and EC for paddy fields but water temperature was low.2. In 1997 and 1998, the following three experiments were conducted at Shenjiangzi village being a typical saline-soil region, Daan city, Jilin province.Experiment to recover grassland : One of the most important factors that caused the degeneration of grassland is overgrazing in this area. So, the effect of keeping-off livestock temporally from grassland were investigated using natural grassland of 650 ha. From the control plot, great effect was observed in recovering vegetation and in the productivity of the grassland.Experiment to improve saline-soil field : The relationships between the amount of soil conditioner and crop growth were investigated for corn cultivation. A combined treatment of multing film and applying aluminum sulfate or gypsum improved corn yield drastically even in the areas where were not suitable for crop production.Experiment to improve saline-soil paddy-field : The effect of irrigation to the leaching of saline, to rice growth and productivity were investigated. When subterranean water pumped up from 8O m below ground was used, rice production rose up to 6,000 kg / ha. High productivity can be expected in the areas where subterranean water is plenty enough for rice cultivation and drainage canal are equipped.