【作者】 冯棣；

【导师】 孙景生；

【作者基本信息】 中国农业科学院 ， 农业水土工程， 2014， 博士

【摘要】 合理开发利用浅层地下储量丰富的咸水（含微咸水）资源发展农业灌溉，对缓解环渤海低平原区淡水资源紧缺矛盾、确保农业稳产高产和生态环境安全具有重要意义。本文以棉花为研究对象，在河北衡水设计畦灌和沟灌两种造墒方式（灌水定额分别为75mm和37.5mm）及1、2、4、6、8g/L五个矿化度水质处理（分别记为B1、B2、B3、B4、B5处理和F1、F2、F3、F4、F5处理），研究了咸水长期定位灌溉对土壤环境和棉花生长的影响效应，探讨了适于该区咸水安全灌溉的评价方法，并提出了咸水灌溉的适宜灌水方式与灌溉水矿化度指标。取得的主要成果如下：（1）确定了土壤盐分变化率和随灌溉水带入盐分的脱盐率是咸水灌溉棉田盐分补排平衡分析的重要评价指标。与2006年开始咸水定位灌溉试验0～1.0m土层初始土壤盐度相比，2013年试验结束时B1、F1和F2处理分别出现11.8%、8.7%和10.1%的脱盐，B2处理基本持平，而B3、B4、B5和F3、F4、F5处理分别增加41%、42.9%、90.8%和7.3%、24.5%、65.2%，证明畦灌处理的积盐水平显著高于沟灌处理。最终所有处理86%以上随灌溉水带入的盐分被淋出1.0m土层，B1、B2、B3、B4和B5处理的盐峰分别出现在2.3、2.1、1.9、1.7和1.5m，F1、F2、F3、F4和F5处理的盐峰分别出现在2.1、2.1、1.9、1.9和0.7m，随灌水矿化度的增加，盐峰值在剖面内有上移趋势。（2）揭示了长期咸水灌溉对棉花生长和产量的影响，发现棉花生长指标和产量等在单个棉花生长季与灌水矿化度之间关系密切；而年际间的波动主要受到气象因子和灌水矿化度的共同影响，其中籽棉产量年际波动可能主要受到花铃期平均气温的影响。（3）通过界定棉花耐盐性鉴定指标的判定原则，明确了株高、成铃数、果枝数、霜前花率等都可以作为表征棉花耐盐能力和预知籽棉产量趋势的耐盐性鉴定指标。其中株高和成铃数是预知籽棉产量趋势较为可靠的指标。（4）综合考虑产量、收益、灌水量及灌溉水引入盐量，在确保土壤相对安全和较高收益的情况下，畦灌和沟灌造墒的灌水矿化度指标最高可定为6.0g/L和4.0g/L。（5）提出了适于当地的咸水安全灌溉原则与评价方法，证明连续多年咸水灌溉后，同一灌溉方式下土壤质量随灌水矿化度增加而降低，相比之下，当灌水矿化度不高于6.0g/L时畦灌处理的土壤质量优于沟灌处理，当灌水矿化度达到8.0g/L时沟灌处理的土壤质量较高。综合考虑经济效益和土壤质量，认为在环渤海低平原盐度较低的区域短期开展咸水灌溉是可行的，在咸水造墒播种结合育苗补栽措施条件下最好使用畦灌平播方式植棉，适宜灌水矿化度阈值为6.0g/L。更多还原

【Abstract】 Rational development and utilization of shallow underground saline water resources in agricultureirrigation has important theoretical significance and practical value in relieving the contradictions of theshortage of water resources, as well as ensuring the stabilization of agricultural production andecological environment security in the low land plain area around Bohai Sea. A field study on cottonwas conducted at Hengshui, Hebei province during the2006-2013growing season. Border irrigationand furrow irrigation were adopted to supply pre-sowing water. The irrigation water quota was75mmfor border irrigation and37.5mm for furrow irrigation. Five salinity levels of mineralized water wereincluded in the experiment:1,2,4,6, and8g/L (denoted as B1, B2, B3, B4, and B5for borderirrigation; F1, F2, F3, F4, and F5for furrow irrigation). The response of cotton growing and soilenvironment to long-term saline water irrigation was investigated, and the evaluation method of safetyirrigation with saline water was probed in this research, and appropriate irrigation methods andirrigation water salinity index were obtained. The main results showed that:(1) The change rate of soil salt and the desalinization rate of salt input by irrigation water weredetermined to to be important evaluation indexes in cotton field salt balance analysis of saline waterirrigation and drainage. Compared to the initial soil EC1:5within0～1.0m soil layer in2006(0.25dS/m), the final soil EC1:5in2013decreased by11.8%,8.7%and10.1%for B1, F1and F2treatment,but increased by1.5%,41%,42.9%,90.8%,7.3%,24.5%and65.2%for B2, B3, B4, B5, F3, F4, and F5treatment. It can be seen that the level of soil salt accumulation were higher in border irrigationtreatments significantly. Eventually, more than86%of salt input by irrigation water was leached out ofthe1.0m soil layer for all treatments. The salt peak of B1, B2, B3, B4, B5and F1, F2, F3, F4, F5was2.3,2.1,1.9,1.7,1.5, and2.1,2.1,1.9,1.9,0.7m, respectively. The peak values of salt in the soil profileshowed a tendency to move up with the increasing salinity of the irrigation water under the sameirrigation method.(2) The response of cotton growing and soil environment to long-term saline water irrigation wasrevealed. There was a close relation between salinity of water and the cotton growth index and yield in asingle cotton growing season. Among the years, the interannual fluctuations of all cotton growingindicators and yield were mainly affected by salinity of irrigation water and the meteorological factors.the interannual fluctuations of seed cotton yield might be mainly affected by mean air tempreture atblossing and boll-forming stages.(3) By means of the definition of judging principle of cotton salt resistance appraisal index, cottonplant height, number of boll, number of branches, and pre-frost yield rate all could be used as salttolerance appraisal indices of cotton. Meanwhile, the plant height and number of boll are the mostreliable index to predict the seed cotton yield.(4) Taking yield, price, irrigation quota, and salt input by irrigation water into consideration, andensuring the higher income and the soil safety, the maximum salinity of irrigation water for border irrigation and furrow irrigation treatment was6.0and4.0g/L, respectively.(5) The suitable saline water safety irrigation principle and evaluation method were proposed forthe local. It demonstrated that after7years of saline water irrigation, the soil quality decreased with theincreasing salinity of irrigation water under the same irrigation method; the soil quality were better inborder irrigation treatments when salinity of irrigation water was lower than6.0g/L, the soil quality wasbetter in furrow irrigation treatment when salinity of irrigation water reached to8.0g/L. Considering theeconomic benefits and soil quality, short-term saline water irrigation is feasible in the low plain aroundthe Bohai Sea with the low soil salinity. Border irrigation and conventional planting for cotton aresuggested under pre-sowing irrigation with saline water and transplanting after sowing, and the suitableeigevalue for irrigation water salinity is6.0g/L.更多还原