沟垄集雨种植对麦田土壤呼吸及冬小麦生长发育的影响

发布时间：2018-06-14 23:28

本文选题：沟垄集雨种植 + 冬小麦　；参考：《西北农林科技大学》2017年硕士论文

【摘要】：温室效应是人类目前面临的严峻环境问题,农田是温室气体产生的重要来源,而CO_2是农田排放的主要种温室气体之一。沟垄集雨种植是旱区一种行之有效和重点推广的集雨栽培技术,在旱地农业生产中发挥着重要作用,但是目前关于沟垄集雨种植措施下农田碳排放的研究较少。为此本研究于2014~2016年连续进行两季冬小麦田间试验,设置了4种不同的种植模式,包括三种不同沟垄比的集雨种植,分别为:20cm:40cm(P40)、30cm:30cm(P30)、40cm:20cm(P20),以及对照(CP,常规平作种植模式);测定了沟垄集雨种植和传统平作种植下冬小麦的土壤呼吸动态变化、土壤水热和冬小麦的生长发育及产量表现。本研究将为农田温室气体减排和建立作物高产稳产技术体系提供理论依据。主要研究结论如下:(1)4个处理的土壤呼吸速率在越冬期最低,从返青期开始升高,峰值出现在扬花期前后。冬小麦苗期和越冬期,4个处理的土壤呼吸速率表现为P40P30P20CP,从小麦返青开始随着生育进程的推进,平作处理的呼吸速率逐渐升高,在拔节-扬花期之后CP高于P30和P20,P40处理呼吸速率在冬小麦生长季(除了返青-拔节期)最高。(2)沟垄集雨种植提高了苗期和越冬期的土壤温度,能有效蓄水保墒,垄的宽度越宽集雨效果越好,7.6cm和12cm土层体积含水量均表现为P40P30P20CP。但是沟垄集雨处理促进根系对深层土壤水分的消耗利用,从拔节期开始沟垄集雨处理的土壤剖面贮水量低于平作,在干旱年份,垄的宽度越大,土壤剖面贮水量相比平作越低。(3)土壤温度和水分对土壤呼吸的影响具有协同性。土壤呼吸与温度的相关系数达极显著水平(P0.01),土壤呼吸与水分的相关系数小于与温度的相关系数,两年试验中温度敏感系数Q10在1.57~1.95之间。温度指数模型能解释呼吸变化的34.1%~68.2%,水热双因子的二次方程模型能解释的呼吸变化的59.9%~74.1%,应综合考虑土壤水分和温度对土壤呼吸的影响。(4)3个沟垄集雨处理提高了作物的籽粒产量。沟垄集雨种植能够通过改善土壤的水温状况,促进冬小麦生长,提高冬小麦单位面积茎数、LAI和生物量积累。两季冬小麦单位公顷穗数分别表现为P40P30P20CP和P40P20P30CP。降雨较为充足的年份,沟垄集雨种植产量较平作提高14.9%~42.5%,在干旱年份,沟垄集雨处理产量较平作提高了52.1%~89.6%。两年试验P40处理在3个沟垄集雨处理中产量最高,增产比例最大。(5)沟垄集雨种植收集无效降雨,减少蒸发,增加了土壤水分的有效性,提高了冬小麦的水分利用效率。在降雨较为充足年份沟垄集雨种植冬小麦水分利用效率提高了11.0%~37.4%,在干旱年份沟垄集雨种植冬小麦水分利用效率提高了50.1%~72.6%,两年试验,P40处理在3个沟垄集雨处理中水分利用效率最高。(6)沟垄集雨种植增加了CO_2的累计排放量,但是CO_2排放强度低于平作。2014~2015年冬小麦生长季CO_2排放强度表现为CPP20P40P30,4个处理间差异不显著。2015~2016年冬小麦生长季CO_2排放强度表现为CPP30P20P40,3个集雨处理显著低于平作(P0.05)。
[Abstract]:Greenhouse effect is a serious environmental problem that human beings are facing at present. Farmland is an important source of greenhouse gas production, and CO_2 is one of the main greenhouse gases emitted by farmland. The ridge and ridge rain collecting is an effective and important popularized rainwater harvesting technique in dry land, which plays an important role in the agricultural production of dry land, but it is currently concerned. There are few studies on the carbon emission of farmland under the furrow and ridge collecting measures. In this study, in this study, two winter wheat field trials were conducted continuously in the year of 2014~2016, and 4 different planting patterns were set up, including three different furrow ratios, 20cm:40cm (P40), 30cm:30cm (P30), 40cm:20cm (P20), and the control (CP, conventional Cropping Model). The dynamic changes of soil respiration, soil water heat and the growth and yield of winter wheat were measured. This study will provide a theoretical basis for the emission reduction of greenhouse gases and the establishment of high and stable yield of crops in farmland. The main conclusions are as follows: (1) 4 treatments of soil respiration The rate was lowest in the overwintering period, rising from the green period, the peak appeared before and after the flowering stage. The soil respiration rate of the 4 treatments was P40P30P20CP. The respiration rate of the flat growing process increased gradually with the advancement of the growth process, and the CP was higher than P30 and P20 and P40 after the jointing and flowering stage. The rate of physical respiration is the highest in the growing season of Winter Wheat (except for the green and jointing period). (2) the planting of ridge and rain in the furrow increases the soil temperature of the seedling and the overwintering period, and can effectively save the soil moisture. The better the rainfall effect is the wider the width of the ridge, the volume of the soil volume of 7.6cm and 12cm is P40P30P20CP., but the furrow rain collecting treatment promotes the root to the deep soil. The water consumption of the soil section from the jointing stage was lower than that of the flat soil section. In the drought years, the larger the width of the ridge, the lower the soil profile storage water. (3) the effect of soil temperature and moisture on soil respiration was synergistic. The correlation coefficient of soil exhalation and temperature was very significant (P0.01), soil The correlation coefficient of soil respiration and moisture is less than the correlation coefficient with temperature. The temperature sensitivity coefficient Q10 is 1.57~1.95 in two years. The temperature index model can explain the 34.1%~68.2% of the respiration change. The two equation model of the water heat double factor can explain the 59.9%~74.1% of the respiration change. The soil respiration and temperature should be taken into consideration in the soil respiration. (4) 3 furrow raining treatment improved the grain yield of the crop. By improving the soil water temperature, it can promote the growth of winter wheat, increase the number of stems per unit area of winter wheat, LAI and biomass accumulation. The number of per hectare per hectare per unit of Winter Wheat in two winter wheat is shown to be more abundant in the rainfall of P40P30P20CP and P40P20P30CP., respectively. In the year of drought, the yield of raining in furrow and ridge collection was increased by 14.9%~42.5%, and in the drought years, the yield of raining in furrow and ridge was increased in 52.1%~89.6%. two years. The maximum yield and maximum yield were increased by P40 treatment in 3 furrows and ridge collecting. The water use efficiency of winter wheat was higher than that of winter wheat. The water use efficiency of winter wheat increased by 11.0%~37.4%, and the water use efficiency of winter wheat was increased by 50.1%~72.6% in the drought year. The water use efficiency of P40 treatment in the 3 furrow raining treatment was the highest. (6) furrow ridge set. Rain planting increased the cumulative emission of CO_2, but the intensity of CO_2 emission was lower than that of.2014~2015 years. The CO_2 emission intensity of the winter wheat growing season was not significant, and the difference between CPP20P40P30,4 treatments was not significant. The CO_2 emission intensity of the winter wheat in the growth season of winter wheat was significantly lower than that of the level of CPP30P20P40,3 (P0.05).
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S512.11;S154

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