草木樨与脱硫石膏对内蒙古盐渍化土壤的改良培肥作用与效果  

Improvement of Na_2SO_4 saline soil by Melilotus Mill and desulfurization gypsum in Hetao Inner Mongolia

作　　者：温国昌 徐彦虎 林启美[1] 李贵桐[1] 赵小蓉[1] 

机构地区：[1]中国农业大学资源与环境学院,北京100193

出　　处：《干旱地区农业研究》2016年第1期81-86,共6页Agricultural Research in the Arid Areas

基　　金：国家"十二五"科技支撑计划项目(2013BAC02B06)

摘　　要：在内蒙古河套地区硫酸钠盐渍化土壤布置田间试验,研究种植草木樨和施用脱硫石膏(30 t·hm^(-2))对盐渍化土壤的改良作用与效果。结果表明:春季灌溉洗盐大幅度降低土体土壤p H值、盐渍化程度,尤其是表层土壤,p H值和EC值分别降低1.54~2.07和7%~69%,主要盐分离子Na+和SO42-分别降低了80%和39%。施用脱硫石膏对灌溉洗盐没有显著的影响,但显著降低土壤有机质、有效磷、有效钾含量,分别降低了20%、15%和50%;施用脱硫石膏提高草木樨生物量34%,但植株磷含量降低了42%。种植草木樨大幅度降低土壤EC值和盐分离子含量,表层土壤主要盐分离子Na^+和SO_4^(2-)含量分别从670 mg·kg^(-1)和2 500 mg·kg^(-1)降低至3.38 mg·kg^(-1)和140.80 mg·kg^(-1),降低了200倍和16倍;土壤有机质和碱解氮含量分别提高了6%和40%,而有效磷、有效钾却降低了49%和26%,同时施用脱硫石膏,尽管对土壤p H值、EC值和盐分离子浓度没有太大的影响,但显著提高了土壤有机质和碱解氮含量,有效磷和有效钾含量也相对有所增加。说明草木樨具有很好改良培肥盐渍化土壤作用,与脱硫石膏也有一定的交互作用,可加快盐渍化土壤改良培肥,但需要增加磷钾肥的施用。To investigate the improvement results from both Melilotus Mill and desulfurization gypsum （30 t· hm^-2） on salt contents and properties, a field experiment was set up in the Na2SO4 saline soil at Hetao Inner Mongolia. The re- sults showed that the irrigation in spring largely reduced the pH and salinization level. In particular, the values of pH and EC in surface soil were reduced by 1.54 - 2.07 and 7% - 69% respectively. The concentrations of main salt ions Na^＋ and SO4^2- became decreased by 80% and 39%, respectively. Addition of desulfurization gypsum had no significant effect on salt washing, but reduced soil organic matter, available P and K by 20%, 15% and 50%, respectively, implying that addition of desulfurization gypsum enhanced nutrient leaching during irrigation washing. The amendment of desulfurization gypsum resulted in 34% increase of Melilotus Mill biomass. However, the P content in plant tissue was significantly reduced by 42 %. Melilotus Mill largely reduced soil EC and ion contents. The concentrations of main ions of Na^＋ and SO4^2- in the surface soil were decreased from 670 mg·kg^-1 to 3.38 mg·kg^-1, and from 2 500 mg·kg^-1 to 140.80 mg·kg^-1, respectively, which was about 200 times and 16 times lower than those in the soil before cultivation. The contents of both soil organic matter and alkaline-released N were elevated by 6% and 40% respectively. In contrary, available P and K went decreased by 49 % and 26 %, respectively. Though addition of Melilotus Mill had not significant impacts on soil pH, EC and salt ion concentration, it significantly lifted soil organic matter, alkaline-released N, available P and K. It was thus concluded that Melilotus Mill had a marked function in improving saline soil. There was also synergistic effect between Melilotus Milland desulfurization gypsum. To maintain available P and K nutrients levels in soil, additional PK fertilizers might be needed.

关 键 词：草木樨 脱硫石膏 硫酸盐盐渍化土壤 内蒙古河套地区 

分 类 号：S156.4[农业科学—土壤学]