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内蒙大小黑河流域属干草原地带,三面都有山地和丘崗包围,高地岩石风化释放的盐类随径流汇聚而下,再以地势低平,排水不暢,地下水埋藏较浅(2—3米),地下水矿化度为0.5—5克/升,并多含有碳酸根。这些情况都是苏打盐土的形成因素。苏打的来源可能主要为次生黄土台地和平原所埋藏的湖相沉积物中含有苏打,其次为来自大青山地区岩石的风化。现代沼泽洼地和新干涸的洼地的边缘也积累有苏打,这可能是硫酸钠的生物化学还原作用的结果。苏打草甸盐土可演变为碱化土壤,如经利用可变为埋藏性苏打盐化草甸土。大小黑河流域中的苏打盐土多属氯化物苏打盐土。这种盐土的特性是:可溶盐较少,表层约1%左右,碳酸根含量大于0.5毫克当量,钠鉀离子占阳离子总量90%以上,pH大于10,土壤几乎不含石膏,交换性钠占全部交换量60—80%;有机质约0.3%左右,水溶性有机质占有机质总量4—5%;易溶性SiO_2含量每百克土中约0.7—0.8%;一般质地较粗,土壤自然含水率和毛管水含量都较低,土壤易于干燥,结持力大,见水易于分散和膨胀,透水性很差。这种土壤的改良,最好是淤灌排水结合种植绿肥牧草,也可施用炉渣、黑矾或石膏。目前虽未进行冲洗,但也要采取排水措施,控制地下水位,防止苏打在土体内之继续累积,黑河可用来排水,先疏浚其下游。
Inner Mongolia Heihe Basin is a steppe steppe surrounded by mountains and mound on all three sides, high rock weathering the release of salts with runoff convergence, and then the low level, poor drainage, groundwater buried shallow (2-3 meters ), Groundwater salinity of 0.5-5 g / L, and more contain carbonate. These are the formation of soda salt soil. The source of soda may mainly be soda in lacustrine sediments buried in the secondary loess plateaus and plains, followed by the weathering of rocks from the Daqingshan area. Soda also accumulates on the edges of modern swamp depressions and newly dried depressions, which may be the result of the biochemical reduction of sodium sulfate. Soda Meadows Saline can evolve into alkalized soils that can be converted to buried soda salinized meadow soil if utilized. The size of the soda ash in the Heihe Basin mostly chlorinated soda salt. The characteristics of this salt soil are: less soluble salt, the surface of about 1%, carbonate content greater than 0.5 mg equivalent, sodium and potassium ions accounted for more than 90% of the total cation, pH greater than 10, the soil is almost free of gypsum, exchangeability Sodium accounts for 60-80% of the total amount of exchange; about 0.3% of organic matter, accounting for 4-5% of total organic matter; soluble SiO 2 content of about 0.7-0.8% per 100 grams of soil; generally coarse texture, natural soil Moisture content and capillary water content are low, the soil is easy to dry, knot perseverance, see the water easily dispersed and expanded, poor water permeability. This soil improvement, preferably by combining irrigation and drainage with planting green manure pasture, can also be applied slag, black alum or gypsum. Although no flushing has been carried out at present, drainage measures should be taken to control the groundwater table to prevent the continued accumulation of soda in the soil. The Heihe River can be used for drainage and dredging its downstream first.