生物炭不同用量与施用年限对土壤水分运动及溶质运移的影响

发布时间：2018-05-12 16:12

本文选题：生物炭 + 黑土区　；参考：《东北农业大学》2017年硕士论文

【摘要】：东北黑土区是中国重要的商品粮基地,占全国粮食总产五分之一。黑土中富含有机质,养分含量高,有深厚的腐殖质层和良好的物理、化学及生物学特性,是中国重要的土壤资源。然而当前黑土区水土流失严重,富含有机质、养分的黑土层持续流失,土壤容重不断增大,导致土壤持水、保肥能力持续下降,农作物产量下降,严重威胁国家和地区粮食安全及农业可持续发展。《十三五规划纲要》将加强黑土区保护和加快实施东北节水增粮列入了推进农业现代化的重点。生物炭技术利用农业秸秆等废弃物对土壤进行改良修复,在低碳环保的同时提高水肥利用效率,使农作物增产保收,是农业可持续发展的重要研究方向,特别是对东北黑土区丰富的秸秆资源的绿色循环高效利用具有十分重要的意义。本试验地点选在北安市红星农场,采用径流小区结合室内试验,在自然生长条件下,分析连续两年不同生物炭施用量处理对土壤理化性质、土壤水分运动参数和溶质运移参数的影响,建立并验证土壤水分运动和溶质运移模型,对模拟结果进行分析,得到以下结论:1.随着生物炭添加量的增加,两年试验的各处理容重逐渐降低,总孔隙度逐渐增加。生物炭的连续两年施用都明显提高了土壤中水稳性团聚体的含量以及总有机碳含量,且提高幅度较大。水稳性团聚体增幅为:17.29%~126.20%;总有机碳含量增幅为:36.19%~196.63%。不同处理的p H,有机质,有效磷,速效钾均随着生物炭添加量和施用年限的增加而增加,其中有机质增加最为显著。土壤田间持水量和饱和含水率均随着生物炭累积施用量的增加而增加。生物炭有效改善了土壤持水、保水的能力,提高了土壤储水性能,有利于作物抗旱,达到节水增产的目的。2.不同施用量、连续两年的生物炭均增加了耕层的土壤持水能力。生物炭对进气值倒数的影响最为显著。两年试验结果相比较,继续施用生物炭仍能改善土壤水分特征曲线,显著提高土壤的持水能力。当体积含水率小于0.40 cm3·cm-3时,生物炭抑制了土壤水分在水平方向上的运动;当体积含水率大于0.40 cm3·cm-3时,生物炭的存在提高了土壤水分的水平扩散能力。第二年连续施加生物炭对水分扩散率仍具有一定的影响,但当生物炭的累计施用量持续增加,其作用效果开始减弱。随着生物炭添加量和施用年限的增加,非饱和导水率逐渐增加,其波动范围也逐渐增加。生物炭能提高土壤的导水能力,改善土壤水力学性质,从而提高土壤水分利用效率,保证作物产量。各生物炭处理的弥散系数均较0 t/hm2的处理有所增加,且随着生物炭施用年限的增加逐渐增加。3.根据土壤水动力学理论,结合试验地区的具体情况,建立了土壤水分运动与溶质运移模型。通过对降雨后20分钟、1小时和12小时的土壤水分、溶质含量的模拟值与实测值的对比发现模型误差在可允许范围内,表明了模型在试验区生物炭施用条件下可以适用,模型准确、可靠。4.由模拟结果得:各处理土壤剖面含水率从小到大为0 t/hm225 t/hm250 t/hm275t/hm2100 t/hm2,随着生物炭施用年限的逐渐增加,土壤剖面含水率随之增加,生物炭的施用增加了土壤含水率,提高了土壤的持水能力,有利于作物更好的利用水分,达到高效利用水资源的目的。各处理土壤剖面溶质含量从小到大依次为0 t/hm225 t/hm250 t/hm275t/hm2100 t/hm2,生物炭的施用减少了土壤养分的流失,且生物炭施用量越高,土壤溶质含量越大。生物炭使土壤中赋存更多的养分,有利于养分的滞留和赋存,从而更有利于作物生长发育。
[Abstract]:The northeast black soil area is an important commodity grain base in China, accounting for 1/5 of the total grain production in China. The black soil is rich in organic matter, high in nutrient content, with a deep humus layer and good physical, chemical and biological characteristics. It is an important soil resource in China. However, the soil and water loss of the black soil area is serious and the black soil rich in organic matter and nutrients at present. Continuous loss, soil bulk density continues to increase, lead to soil water holding, the ability to maintain fertilizer, crop yield decline, and seriously threaten food security and sustainable agricultural development in countries and regions. < 13th Five-Year planning outline > will strengthen the protection of the black soil area and accelerate the implementation of the northeast water saving and increasing grain to promote the modernization of agriculture. It is an important research direction for the sustainable development of agriculture, especially the green recycling of the rich straw resources in the black soil area of Northeast China, which is of great significance. In Bei'an Red Star Farm, the effects of different biological charcoal dosage on soil physical and chemical properties, soil moisture movement parameters and solute transport parameters were analyzed under natural growth conditions. The model of soil water movement and solute migration was established and verified. The following conclusions are obtained: 1. with the increase of the amount of biological carbon, the bulk density of the two years experiment gradually decreased and the total porosity increased gradually. The continuous two years application of biological carbon significantly increased the content of water stable aggregates and the total organic carbon content in the soil, and the increase was greater. The increase of water stability aggregates was 17.29%~126.20. The increase of total organic carbon content was as follows: the increase in organic matter, effective phosphorus and available potassium increased with the increase of the amount of biological charcoal and the number of years of application, and the increase of organic matter was the most significant. The soil water holding capacity and saturated water content increased with the increase of the cumulative amount of biological charcoal. The Biocharcoal was effectively modified by 36.19%~196.63%.. Good soil water holding capacity, water retention capacity, improve the performance of soil water storage, is conducive to the drought resistance of crops, to achieve the purpose of water-saving and increasing production of.2. different dosage, two years of continuous biological carbon increase the soil water holding capacity of the plough layer. Biological carbon has the most significant effect on the intake value. Two years experiment results are compared, and continued application of biological carbon still can be used. The soil moisture characteristic curve improved soil water holding capacity. When the volume water content was less than 0.40 cm3. Cm-3, biological carbon inhibited the movement of soil moisture in the horizontal direction. When the volume water content was more than 0.40 cm3. Cm-3, the existence of biological carbon increased the horizontal diffusion capacity of soil moisture. Second years of continuous application of biological carbon was applied. It still has a certain influence on the water diffusivity, but when the cumulative application of biological carbon continues to increase, its effect begins to weaken. With the increase of the amount of biological carbon and the increase of application years, the unsaturated water conductivity increases gradually and its fluctuation range increases gradually. Increasing soil water use efficiency and ensuring crop yield. The diffusion coefficient of each biochar treatment increased more than that of 0 t/hm2. With the increase of biological carbon application years, the soil water movement and solute transport model was established according to the soil hydrodynamic theory and the specific conditions in the experimental area. The comparison of soil moisture and solute content between 20 minutes, 1 hours and 12 hours after rainfall shows that the model error is within the allowable range. It shows that the model can be applied under the condition of biological carbon application in the experimental area. The model is accurate and reliable.4. is obtained from the simulated results: the water content of each treatment soil section is 0 t/hm225 t/ from small to large. Hm250 t/hm275t/hm2100 t/hm2, with the increasing of biological carbon application years, the soil moisture content increased, the application of biological carbon increased the soil moisture content, increased the water holding capacity of the soil, was beneficial to the better use of water and the purpose of efficient use of water resources. Each treatment soil profile content from small to large In turn, 0 t/hm225 t/hm250 t/hm275t/hm2100 t/hm2, the application of biological carbon reduces soil nutrient loss, and the higher the amount of biological charcoal, the greater the soil solute content. Biological carbon makes more nutrients in the soil, is conducive to the retention and occurrence of nutrients, thus more favorable for crop growth and development.

【学位授予单位】：东北农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S152.7;S153

【参考文献】