设施土壤污染障碍与减氮增效技术研究

Study on Pollution Barriers of Facility Soil and Technology of Reducing Nitrogen and Increasing Efficiency

为科学指导设施土壤的管理,保证土壤有足够产出的同时,对生态环境的负面影响保持在可控的范围,对宿豫区典型的设施土壤进行样品采集,测定土壤有机质、酸碱度、电导率以及部分有效性养分和水溶性盐分离子含量。结果表明,设施土壤pH为5.62~6.35,土壤发生明显的酸化现象;土壤电导率(EC)为0.66~5.44 mS/cm,多数土壤EC值均超出了一般作物生长的适宜范围;土壤有机质含量为15.71~21.95 g/kg,难以满足设施作物高产的需求。土壤速效氮含量为32.8~711.7 mg/kg,总体水平偏高,变异系数达到88.1%,氮肥施用很不平衡;土壤速效磷含量为30.1~100.9 mg/kg,基本能满足高产需求;土壤速效钾含量为61.7~517.5 mg/kg,平均为203.4 mg/kg。土壤水溶性钾、钠、钙、镁平均含量分别为100.2、1672.7、1461.9和1204.3 mg/kg,镁/钾电荷比平均40.9,导致土壤相对缺钾的问题比较突出;土壤水溶性氯离子、硫酸根、硝酸根平均含量分别高达2781.7、1252.0和1223.8 mg/kg,都有可能影响作物的正常生长。土壤有效硼、钼、锰平均含量分别为0.37、0.19和6.68 mg/kg,分别处于缺乏、中等、中等水平。减氮对甘蓝生物学和经济产量均没有明显影响,底施平衡肥处理有利于提高甘蓝的生物学产量和经济产量;减氮对甘蓝含氮率和累计吸氮量均有减少的趋势;底施平衡肥和减氮均在一定程度上降低土壤电导率和降低土壤硝态氮含量。

In order to scientifically guide the management of facility soil,ensure sufficient output of soil,and keep the negative impact on ecological environment in controllable range,samples were collected from typical facility soils in Suyu District to determine soil organic matter,pH,electrical conductivity and contents of some available nutrients and water-soluble salt ions.The results showed that the pH of facility soil was 5.62-6.35,and the soil was obviously acidified;soil EC value was 0.66-5.44 mS/cm,and most soil EC values exceeded the suitable range for general crop growth.Soil organic matter content was 15.71-21.95 g/kg,which was difficult to meet the demand of high yield of protected crops.The content of available nitrogen in soil was 32.8-711.7 mg/kg,which was on the high side,with a coefficient of variation of 88.1%,and the application of nitrogen fertilizer was unbalanced.The content of available phosphorus in soil was 30.1-100.9 mg/kg,which could basically meet the demand of high yield.The content of soil available potassium was 61.7-517.5 mg/kg,with an average of 203.4 mg/kg.The average contents of water-soluble potassium,sodium,calcium and magnesium in soil were 100.2,1672.7,1461.9 and 1204.3 mg/kg,respectively,and the average charge ratio of magnesium to potassium was 40.9,which leads to the problem of relative potassium deficiency in soil.The average content of water-soluble chloride ion,sulfate ion and nitrate ion in soil was as high as 2781.7,1252.0 and 1223.8 mg/kg,respectively,which may affect the normal growth of crops.The average contents of available boron,molybdenum and manganese in soil were 0.37,0.19 and 6.68 mg/kg,which were in the deficient,medium and medium levels respectively.Nitrogen reduction had no obvious effect on the biological and economic yield of cabbage,but bottom application of balanced fertilizer was beneficial to improve the biological and economic yield of cabbage.Nitrogen reduction had a tendency to reduce nitrogen content and cumulative nitrogen uptake of cabbage.Applying balanced fertilizer at the bottom and reducing nitrogen could reduce soil conductivity and nitrate nitrogen content to a certain extent.