【作者】 李鑫；

【导师】 张颖；

【作者基本信息】 东北农业大学 ， 生态学， 2012， 硕士

【摘要】 黑龙江省是我国的农业大省,其独特的地理区域和气候条件适宜甜菜种植,甜菜产量相对较大,制糖加工预处理洗涤过程中冲洗块茎产生的废水量也较多。若采用传统生化降解工艺治理废水,不仅处理周期长,而且成本较高。甜菜冲洗废水相对安全(含丰富的营养元素,且不含重金属及病原菌等有害物质),将其土地利用不仅节约水资源,还能降低治理成本及环境负荷,但是土壤对甜菜冲洗废水土地利用的响应关系尚不明确。因此,本研究针对土壤对甜菜冲洗废水(以下简称废水)土地利用的响应开展研究,选取废水灌区典型作物(玉米及大豆)土壤为研究对象,以灌前土壤为背景值,井水灌区土壤作为对照,采样并测定作物地不同土层深度土壤pH值、速效养分、电导率值(EC)、交换性钠、阳离子交换量(CEC)及土壤盐分离子含量,并将所得的结果进行相关性及主成分分析以评价废水土地利用对土壤的安全效应。本研究同时分析废水灌溉对作物产量及地下水的影响。主要研究结果如下1.与井水灌区及灌前相比较,废水灌区玉米地及大豆地0-20cm土层pH值略有降低,速效养分含量显著增加,有利于改善土壤品质,促进作物生长。2.废水灌溉并未导致玉米地及大豆地土壤盐分积累,各层碱化度(ESP)远小于5%这一临界标准。废水灌溉短期未对土壤产生盐渍化风险,长期灌溉结果需进一步监测。3.速效养分与盐渍化等指标主成分分析表明,经废水灌溉,两种作物地各层土壤速效养分及CEC变化较ESP快,说明废水灌溉对土壤养分及保肥能力的提高具有积极作用。同时表明,废水灌溉导致土壤出现碱化的风险较低。4.废水灌溉没有明显地改变土壤胶体原有的平衡状态及离子分布规律,对土壤结构的稳定性产生不良影响的风险较低。5.废水灌区土壤EC与离子之间的相关性分析表明,EC值与HCO3-及SO42-含量均呈现一定的正相关性。长期施用废水灌溉土壤,只要控制好废水中SO42-及HCO3-浓度,维持在本试验浓度值,则土壤产生次生盐渍化,地下水产生矿化风险的可能性均较小。6.废水灌区较井水灌区能提高作物产量,玉米及大豆产量增幅分别为7.79%和4.94%。7.废水灌区地下水质较灌前及井水灌区未表现出明显变化,短期内未对地下水环境造成不良影响。考虑到灌溉强度、降雨淋洗、土壤质地、水力传导速率(0.23mm/min)及土壤持水能力(35.40%)等因素,长期灌溉对地下水环境产生负面影响的几率较低。通过研究土壤对甜菜冲洗废水土地利用的响应,表明这一水资源利用既能解决农业灌溉水体短缺问题,同时作为特殊的“液体肥”又能有效地提升土壤肥力进而提高作物产量。此研究对综合运用甜菜冲洗废水土地利用具有重大的现实意义。更多还原

【Abstract】 Heilongjiang, as a major agricultural province, due to the unique geography location and climate condition, is very suitable for sugar beet planting. The rinse processing of sugar production pretreatment has discharged abundant wastewater because of vast water washing root tuber of sugar beet. If the water is treated by traditional biochemistry degradation technology, long period and high cost about treatment are problems. Sugar beet rinse water (SBRW) is safe because it contains amounts of nutrients, and does not contain heavy metals and pathogens for the safety of sugar processing. Land application with SBRW can not only save irrigation water and reduce the treatment cost, but also ease the loading of environment. However, it is uncertain to know the response of soil to the land application with SBRW. Therefore, the study mainly focused on the response, by taking the typical crop (corn and soybean) soil irrigated with SBRW as research objetive, and sampling as well as measuring soil pH, available nutrients, EC, exchangeable sodium, cation exchange capacity (CEC), soil salinity (EC) and ion contents. Samples were also collected in other plot:pre-irrigation (provided reference "background" values), well water (WW) irrigation (served as the control) site. Correlation analysis and principal component analysis (PCA) were used to evaluate impact of SBRW irrigation on safety effect of the whole soil profile. Meanwhile, the study also analyzed the impact on yield and groundwater with SBRW irrigation. The main results were listed as follows:1. Compared with WW irrigation site and pre-irrigation, the pH decreased at SBRW irrigation site both in corn and soybean soil at the depth of0-20cm and the contents of available nutrients also improved in the soil layer (0-20cm). SBRW would improve the soil quality and boost the growth of crop.2. SBRW, characterized by high salinity, did not cause salt accumulation of soil, and the exchangeable sodium percentage (ESP) in each soil layer was far below the critical value (5%). SBRW did not cause the risk of soil secondary salinization in a short term. Further researches are requested to monitor long-term soil salinity.3. The results of PCA showed that soil available nutrients and CEC changed more remarkably than ESP in both the two crop soil. The results indicated that SBRW irrigation made positive effects on soil nutrients and fertilizer-conserving capacity while it had little influence on ESP.4. SBRW irrigation had no obvious impact on the original balanced condition of soil colloid and the distribution law of ion, and had low risk of negative effect on stability of soil structure.5. Correlation analysis results between EC and soil salt ions in both the two crop soils irrigated with SBRW indicated that EC had showed positive relationship with contents of HCO3-and SO42-. In the long term, as long as maintaining the concentrations of SO42-and HCO3-in a suitable level, just as in the study, SBRW irrigation would have little risk of secondary salinization of soil and mineralization of groundwater.6. Compared with WW irrigation, SBRW irrigation could effectively enhance the yield of crop. Yields of corn and soybean had improved7.79%and4.94%, respectively.7. Compared with WW irrigation and pre-irrigation, SBRW irrigation did not have negative effect on characteristics of groundwater in a short time. Considering the irrigation loading, rainfall washing, soil texture, soil’s hydraulic conductivity (0.23mm/min) and specific retention (35.40%), SBRW irrigation would have little effect on groundwater in a long term.By researching on the response of soil to the land application with SBRW, results confirmed that besides as irrigant, SBRW was also as a "liquid fertilizer" for improvement of soil fertility and crop yield. The study played an important role in guiding and utilizing SBRW as irrigant.更多还原