黄河三角洲农田暗管排盐效果研究

发布时间：2018-05-13 03:25

本文选题：黄河三角洲 + 暗管排水　；参考：《山东农业大学》2015年硕士论文

【摘要】：我国是一个农业大国,近几年来,粮食需求总量持续增长,治理改良盐渍土成为扩大耕地面积、增加粮食产量的有效途径。针对黄河三角洲地区土壤盐渍化严重这一问题,本试验于2012年4月-2013年6月在山东省滨州市小开河引黄灌区完成,通过在田间埋设暗管,研究了暗管排水对滨海地区盐碱土的改良效果。试验共设4个处理,分别:PVC波纹管埋设间距30m、45m、80m,秸秆排水体间距50m,分别用P30、P45、P80、C50表示,其中P30管径最小,其他处理管径一样,暗管埋深均为2.5m。主要结果如下:(1)四个排水处理表层0-20cm、耕层0-60cm、1m土体年内土壤盐分变化趋势基本一致,均比埋管前明显下降,其中0-20cm土壤含盐量下降幅度最大,0-100cm土体土壤含盐量下降幅度最小。春、秋季节土壤积盐,雨季淋溶脱盐,冬季土壤盐分相对稳定。(2)暗管排水能够显著降低土壤盐分含量,四个处理土壤剖面脱盐率变化趋势致:0-30cm土壤脱盐波动较大;30cm-100cm土壤脱盐率沿着土层深度逐渐减小,30-60cm土层中,土壤脱盐率从高到低分别为P45、C50、P30、P80;60-100cm土壤中,土壤脱盐率从高到低分别为C50、P45、P30、P80。随着暗管埋设时间推移,秸秆排水小区0~100cm的土壤脱盐效果将逐渐优于PVC波纹管排水。黄河三角洲地区土壤脱盐效果最优的暗管埋设间距为45~50m。(3)P30、P45、P80、C50四个处理的地下水水位与降雨量的相关系数分别为:0.545、0.525、0.513、0.525,呈现显著相关;与蒸发量的相关系数分别为:0.416、0.478、0.377、0.494,具有显著相关性;与排水量相关系数分别为:0.872、0.908、0.622、0.977,呈现显著相关;与灌水量相关系数分别为:0.824、0.883、0.697、0.832,短期相关性较大,但不显著。蒸发会引起该区域地下水位发生剧烈变化;在没有其它水源对地下水进行补充时,降雨是影响该地区地下水位动态变化的主要因素;良好的排水能够有效降低地下水水位,制定合理灌溉制度,可以防止高矿化度地下水水位上升引起的次生盐渍化。秸秆排水体暗管和PVC波纹暗管均可以通过排水达到控制地下水水位的目的。(4)C50、P45、P30、P80浅层地下水淡化率分别为:46.26%、38.22%、31.68%、24.26%;单位面积排盐量依次为:78.52g、53.53g、24.17g、31.34g;单位面积排水量分别为:0.0128m3、0.0147m3、0.0075m3、0.0063m3;秸秆排水体降渍排盐效果明显优于PVC管排水处理;其排水能力略低于相同管径和埋管间距的PVC管。(5)暗管排水能有效降低土壤容重,增加土壤有机质含量,增加土壤全磷含量,增加土壤速效氮、速效磷、速效钾养分含量;但是土壤全氮量降低,且表层土壤速效养分增量大于耕层土壤。随着埋管时间推移,土壤有机质含量和深层土壤速效养分需要进一步监测,以调整土壤培肥管理措施,提高土地质量。(6)2012年和2013年作物产量较2011年产量增产明显,暗管排水能显著增加作物产量,提高土地产出率,结合当地实际情况,综合考虑暗管排水、排盐效果及土壤脱盐效果,确定黄河三角洲粘质盐化潮土地区适宜的暗管布置为:间距50m、管径315mm的秸秆排水体,或者间距45m、管径315mm的PVC波纹管排水。
[Abstract]:China is a big agricultural country. In recent years, the total amount of grain demand has been increasing continuously. The improvement of saline soil has become an effective way to enlarge the area of cultivated land and increase grain yield. This experiment was completed in the Yellow River irrigation area of the Xiao Kai River in Binzhou City, Shandong Province in April 2012, according to the problem of serious soil salinization in the Yellow River Delta region. The improvement effect of dark pipe drainage on saline alkali soil in the coastal area was studied by buried pipe in the field. 4 treatments were set up, respectively: the spacing of PVC bellows was 30m, 45m, 80m, and the spacing of the drainage body of straw was 50m, respectively, with P30, P45, P80, C50, respectively, of which the P30 pipe diameter was the smallest, the buried depth of the dark pipe was the same as the 2.5m. main result. (1) the change trend of soil salinity in the soil of four drainage treatment surface 0-20cm, plough layer 0-60cm, 1m soil is basically the same, which is obviously lower than that before the buried tube, of which the salt content in the 0-20cm soil decreases the largest, the soil salt content in the soil of 0-100cm is the lowest. Spring, autumn soil soil salt, the rain season leaching desalination, and the soil salt in winter are relatively stable. (2) Four soil desalination rates change trend: 0-30cm soil desalination fluctuates greatly; 30cm-100cm soil desalination rate decreases along the soil depth, and the soil desalination rate from high to low is P45, C50, P30, P80; 60-100cm soil, the soil desalination rate is from high to low in 30-60cm soil. C50, P45, P30, P80., as the dark pipe burial time goes on, the effect of the soil desalination of the soil 0~100cm in the straw drainage area will be better than the PVC corrugated pipe drainage. The best buried spacing of the dark tube in the the Yellow River Delta region is 45~50m. (3) P30, P45, P80, C50 four, the correlation coefficient of the groundwater level and rainfall is 0., respectively: 0. 545,0.525,0.513,0.525 has significant correlation, and the correlation coefficient with evaporation is 0.416,0.478,0.377,0.494, which has significant correlation, and the correlation coefficient of water discharge is 0.872,0.908,0.622,0.977, showing significant correlation, and the correlation coefficient with the irrigation quantity is 0.824,0.883,0.697,0.832, and the short-term correlation is larger, but it is not significant. If there is no other water source to supplement the groundwater, the rainfall is the main factor affecting the dynamic change of the groundwater level in this area. The good drainage can effectively reduce the water level of the groundwater and make a reasonable irrigation system, which can prevent the secondary water level from the high salinity water level rise. Salinization. Straw drainage body dark pipe and PVC corrugated pipe can achieve the purpose of controlling groundwater level through drainage. (4) C50, P45, P30, P80 shallow groundwater desalination rate is 46.26%, 38.22%, 31.68%, 24.26% respectively; the unit area of salt discharge is in turn: 78.52g, 53.53g, 24.17g, 31.34g; unit area drainage is: 0.0128m3,0.0147m3,0.00 respectively: 0.0128m3,0.0147m3,0.00 75m3,0.0063m3; the effect of water drainage of straw drainage body is obviously better than that of PVC pipe drainage treatment; its drainage ability is slightly lower than the PVC tube with the same pipe diameter and buried pipe spacing. (5) the drainage of the pipe can effectively reduce the soil bulk density, increase the content of soil organic matter, increase the content of soil total phosphorus, increase soil available nitrogen, available phosphorus, and the content of available potassium nutrient; but soil The total nitrogen in the soil decreased, and the increment of available nutrients in the surface soil was greater than that in the plough soil. With the time of the burial pipe, the soil organic matter content and the deep soil available nutrients needed further monitoring to adjust the soil fertility management measures and improve the land quality. (6) the yield in 2012 and 2013 was more obvious than that in 2011, and the drainage of the dark pipe could be obvious. In order to increase the yield of crops and increase the yield of land, combining with the actual situation of the local area, considering the drainage of dark tube, the effect of salt discharge and the effect of soil desalination, the suitable arrangement of dark pipe in the area of the clay salted soil of the Yellow River delta is as follows: the spacing 50m, the straw drainage body with the diameter of 315mm, or the spacing of 45m, and the drainage of the PVC bellows of the diameter of the tube of 315mm.

【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S156.42

【参考文献】