江汉平原湖积型涝渍地土壤化学环境及适宜性评价

对江汉平原湖积型涝渍地土壤pH、CEC、EC、有机质、易氧化有机质、速效钾、速效磷和碱解氮等化学性质进行了测定.结果表明:湖积型涝渍地土壤pH多数在6.6～8.5之间,7.6～8.5的面积占71 %,过酸过碱的极少;CEC平均为24.65 cmol/100 g,处于中等水平;土壤EC 95 %在0.10～0.39 mS/cm之间,没有盐渍化的现象;有机质及碱解氮较非涝渍地高,但下降速度较快,平均年递减量分别为1.11 g/kg和1.68 mg/kg;土壤速效钾、速效磷含量中等,但分布极不均匀.因此,在养分含量较低的区域应重视有机物料和磷钾肥的施用.

Evaluation of Soil Chemical Characteristics and Fitness of Lake Sedimentary Waterlogged Land in Jianghan Plain

The pH, CEC, EC, organic matter, oxidable organic matter, available potassium,phosphorus and alkali-decomposed nitrogen were determined from waterlogged soils in Jianghan Plain. Results showed that:(1)The major range of soil pH was from 6.5 to 8.5, and the percentage of soil area with pH ranging from pH 7.5 to 8.5 was 71%, and the soil areas with pH ranging betwen 5.0 and pH 8.5 were very Litle. (2) The mean of CEC from investigated soil was 24.65 cmol/100 g, which was at middle nutrient level. (3) The percentage of soil EC ranging from 0.10 mS/cm to 0.39 mS/cm was 95% and the soil was not salinized. (4) The amount of soil organic matter and alkali-decomposed nitrogen from the waterlogged soil were higher than non-waterlogged soil resperatively,but the decrease rate per year were 1.11 g/kg and 1.68 mg/kg resperatively. (5) The amounts of soil available potassium and phosphorus were at medium level but the distribution of soil nutrients wasn't very uniform.Therefore, organic manure and phosphorus and potassium fertilizers must be applied in the district of low soil fertility.