不同覆盖措施对土壤物理性质和玉米生长发育的影响评价

发布时间：2018-05-24 11:07

本文选题：覆盖 + 物理性质　；参考：《宁夏大学》2017年硕士论文

【摘要】：干旱、缺水是我国农业生产的两大难题,地表覆盖措施是解决旱作农业缺水的有效途径。因此为探究不同地表覆盖措施在半干旱地区旱作农业生产中的调温保墒效果,本论文在宁夏盐池县进行随机小区试验,分析了 3种不同地表覆盖措施(地膜覆盖PM、砾石覆盖GM、秸秆覆盖SM)和对照(无覆盖CK)对土壤性质(土壤含水量、土壤温度、土壤孔隙度、土壤持水量)的影响,并比较了玉米的出苗率以及生长状况的差异;利用染色示踪和图像分析相结合的方法,研究了 3种不同地表覆盖措施(地膜覆盖PM、砾石覆盖GM、秸秆覆盖SM)下土壤的优先流特征和大孔隙分布状况;利用室内土柱模拟,研究了同一厚度下,不同砾石粒径大小以及残膜对土壤中水分运移的影响;运用AHP-模糊综合评判方法对3种覆盖材料的适宜性进行了综合评价,结果表明:1)地膜覆盖和砾石覆盖具有较好的增温效果,有利于提高玉米的出苗率和促进玉米拔节,并有利于延长作物的生长期;3种不同覆盖措施均有一定的保持土壤水分效应,其中砾石覆盖效果显著;与对照相比,覆盖处理下土壤孔隙度、持水量增加,土壤容重降低,土壤结构得到改善。2)2015年,砾石覆盖和地膜覆盖处理下,玉米的出苗率要高于对照,秸秆覆盖处理下,玉米出苗率要低于对照,而在2016年,秸秆覆盖处理的出苗率要高于对照;3种不同覆盖措施都显著增加了各生育期玉米的株高、茎粗和叶面积值;与对照相比,3种覆盖措施均显著提高了玉米的产量,其中以砾石覆盖最高,其次为地膜覆盖,秸秆覆盖玉米产量最低。3)与对照相比,3种不同覆盖处理的土壤的染色剂垂直运移深度相差较大,以地膜覆盖处理下染色深度最大,砾石覆盖次之;土壤的染色面积比例均是表层最大,并且随着深度增大呈现出在波动中下降的趋势;3种不同覆盖措施下均产生了优先流现象,其中以地膜覆盖、砾石覆盖处理下优先流现象最为明显;与对照相比,3种覆盖措施均能增加土壤表层(0-30cm)的土壤孔隙数量,地膜覆盖、砾石覆盖处理下土壤深层的大孔隙数量也要明显高于对照。4)室内模拟不同粒径砾石及残膜对土壤水分运移的影响:不同砾石粒径覆盖对土壤水分入渗影响的室内模拟试验中,结果表明,与对照相比,砾石覆盖表面能够增加水分的累积入渗量;在湿润锋运移距离的模拟试验中,相同时间内,相同覆盖厚度下,以1-2cm粒径砾石覆盖处理的湿润锋运移距离最大和0.25-0.5cm粒径砾石覆盖处理的累积入渗水量最大。不同地膜残留深度土壤水分入渗的室内模拟试验中,结果表明,与对照相比,地膜残留能够抑制土壤中水分的入渗,影响水分下渗。在相同的时间内,0-5cm地膜残留深度和5-1Ocm地膜残留深度的累积入渗量都要小于对照,水分下渗深度也要小于对照处理。5)对3种覆盖处理进行的AHP-模糊综合评判的结果表明,在3种覆盖措施中,以砾石覆盖处理的整体评价最好,其次为地膜覆盖处理。对各个评价指标权重以及2015、2016两年所产生的收益的对比,结果表明:在进行覆盖材料的选择时,要考虑覆盖材料对土壤结构和作物生长所产生的影响以及由此所带来的收益;同时,在以2015、2016年两年当年的玉米市场价格以及覆盖的成本为基础进行的收益测算中,以砾石覆盖处理下的收益最高,其次为地膜覆盖处理。6)综上所述:在不同覆盖措施对宁夏盐池县农田土壤物理性质和玉米生长特性影响的对比研究表明,砾石覆盖能起到良好的调温保墒效果,改善土壤结构,并且能够促进玉米的生长发育,显著提高玉米产量,增加收益,可以进一步推广实施。
[Abstract]:Drought, water shortage is the two difficult problem of agricultural production in our country. The measures of surface cover are the effective ways to solve the water shortage of dry farming. Therefore, in order to explore the effect of temperature and moisture conservation in the dry farming of semi-arid areas, this paper has carried out the experiment in Ningxia Yanchi County, and analyzed 3 kinds of different surface cover measures. The effects of mulching PM, gravel covering GM, straw mulching SM) and control (no covering CK) on soil properties (soil water content, soil temperature, soil porosity, soil water holding capacity), and the difference of seedling emergence rate and growth condition of maize were compared, and 3 different surface cladding methods were studied by combining the method of dyeing tracing and image analysis. Gerzos (film covered with PM, gravel covered with GM, straw mulched SM) the characteristics of soil priority flow and the distribution of macropores. Using indoor soil column simulation, the effect of different gravel size and residual film on soil moisture migration under the same thickness was studied. The suitability of the 3 covering materials by AHP- fuzzy comprehensive evaluation method was carried out. The comprehensive evaluation shows that: 1) film mulching and gravel cover have good warming effect, which can improve the emergence rate of maize and promote the jointing of corn, and promote the growth period of the crops. The soil moisture effect is maintained by the 3 different covering measures, in which the gravel cover effect is significant; compared with the control, the coverage treatment is compared with the control. Soil porosity, water holding capacity increased, soil bulk density decreased, soil structure improved.2. In 2015, under the treatment of gravel covering and mulching, the emergence rate of maize was higher than that of control. Under straw mulching treatment, the emergence rate of maize seedlings was lower than that of the control. In 2016, the seedling rate of straw mulching treatment was higher than that of the control; 3 different coverage measures were taken. The plant height, stem diameter and leaf area value of each growth period increased significantly. Compared with the control, the 3 covering measures significantly increased the yield of maize, among which the gravel covered the highest, the second was the mulching, the straw mulched corn yield was lowest.3. Compared with the control, the vertical migration depth difference between the 3 different covered soils was different. The dyeing depth is the largest and the gravel cover is the largest under the mulching treatment, and the proportion of the soil is the largest in the surface area, and the trend of the decrease with the depth increases. The first flow phenomenon is produced under the 3 different covering measures, in which the ground film is covered and the priority flow is most obvious under the gravel cover treatment. Compared with the control, the 3 coverage measures can increase the amount of soil porosity in soil surface (0-30cm), film mulching, and the number of large pores in the deep soil under gravel cover is also significantly higher than that of the control.4). The effects of different gravel gravel and residual film on soil water migration are simulated in the laboratory. In the simulation test, the results showed that the gravel covered surface could increase the cumulative infiltration of water. In the simulation test of the migration distance of the wetting front, the migration distance of the humid front treated with the 1-2cm gravel cover was the largest and the accumulation of gravel covered with the 0.25-0.5cm particle size in the same time and the same covering thickness. In the indoor simulation test of soil water infiltration of different film residual depth, the results showed that the residue of the film could inhibit the infiltration of water in the soil and influence the water infiltration. In the same time, the residual depth of the 0-5cm film and the residual depth of the 5-1Ocm film were less than the control. The depth of infiltration is also less than that of the control treatment.5). The results of AHP- fuzzy comprehensive evaluation of 3 coverage treatments show that in the 3 coverage measures, the overall evaluation of gravel cover treatment is the best, followed by the film mulching treatment. The weight of each evaluation index and the income generated in the 20152016 years are compared. The results show that the results are as follows: The impact of cover materials on soil structure and crop growth and the resulting benefits should be taken into account when the material is chosen, and the highest yield under gravel coverage, followed by film mulching, is calculated on the basis of corn market prices and covering cost of 20152016 years and two years. To sum up.6) to sum up, a comparative study of the effects of different coverage measures on soil physical properties and maize growth characteristics in Yanchi County of Ningxia showed that gravel cover could play a good effect on temperature and moisture conservation, improve soil structure, promote the growth and development of maize, increase maize yield and increase income, and further promote the growth of corn. Wide implementation.
【学位授予单位】：宁夏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S152;S513

【参考文献】