滴灌条件下水炭耦合对土壤节水保肥和固碳减排综合效应研究

发布时间：2018-04-05 04:11

本文选题：生物炭　切入点：作物生育指标　出处：《内蒙古农业大学》2017年硕士论文

【摘要】：地球是我们人类赖以生存的家园,然而随着近几年工业、农业、经济的快速发展,导致我们的家园不堪重负,温室效应的加剧,气候的异常变化、持续不断的雾霾无一不在向我们敲响保护环境的警钟,因此,保护环境已刻不容缓。农业是我们人类的能量之源,然而持续加大的农业集约化压力,化肥施用数量和强度不断增加,导致土壤板结酸化、面源污染问题等不断加重,且农业是重要的温室气体排放源之一,对温室效应的影响不可小觑,据国内外研究人员研究发现,生物炭在土壤改良和固碳减排等方面卓有成效。因此,分别于2015和2016年通过田间小区试验,在膜下滴灌条件下设置不同秸秆生物炭施用量(0、15、30、45t/hm~2)和不同灌溉水量梯度(张力计控制灌水下限:-35、-25、-15kPa),研究水炭(生物炭)耦合对土壤理化性质、作物生长发育、产量以及农田土壤温室气体(CO2、CH4、N20)排放的影响规律,并估算CH4和N20的综合增温潜势(GWP)及其排放强度(GHGI),以期生物炭能够在改善土壤状况、减缓温室气体排放方面有一定效果,从而找出适宜的生物炭施用量和灌溉水量,这不仅为生物炭在内蒙古地区的广泛推广与利用提供理论依据,同时也促进了农业和生态环境的可持续发展。研究结果如下:1)土壤理化性质研究。施用生物炭在不同的灌水下限均提高了耕层土壤电导率,且随着生物炭施用量的增加基本呈先增加后降低的趋势;提高耕层土壤解碱氮、速效钾、有机质和有效磷含量,其中,高生物炭施用量处理有机质和有效磷增幅最大;在三叶期和拔节期随着生物炭施用量的增加土壤表层温度逐渐增加,在抽雄期之后,除30t/hm~2的生物炭处理外,其它均低于对照,同一生物炭施用量,在三叶期随着灌水量增多,土壤表层温度呈降低趋势,在之后的生育期均表现为W2W1W3,其中,灌水下限-25kPa和生物炭施用量30t/hm~2是提高土壤表层温度的较佳水炭组合;生物炭和灌溉水量对土壤pH基本无影响;适量的生物炭施用量在不同的灌溉定额下均可以提高土壤含水率,其中,15t/hm~2和30t/hm~2可较大限度地提高土壤含水率。2)玉米生长发育和产量研究。灌水和施炭均显著提高玉米全生育期株高、茎粗、玉米叶面积指数(从拔节到成熟);生物炭显著提高产量、玉米收获指数,灌水量对产量和收获指数影响不显著;生物炭对干物质影响不显著,灌水量在枯水年显著提高玉米干物质量,在丰水年影响不显著;水炭交互作用对上述作物指标都不显著。3)农田温室气体排放规律研究。适量施用生物炭能够有效地降低玉米农田土壤CO2、N20和CH4的季节累计排放总量,进而降低玉米农田土壤CH4和N20的综合增温潜势(GWP),最终降低温室气体排放强度(GHGI),降幅都达40%以上,综合考虑,添加30t/hm~2的生物炭是比较合适的生物炭施用量,农田CO2、N20和CH4两年里的平均季节累计排放总量分别减少 3016.81、0.46、0.31 kg/hm~2。4)肥料利用效率及经济效益。水炭耦合显著提高氮、磷、钾肥的肥料利用率和经济效益,其中灌水下限-25kPa,生物炭施用量15t/hm~2和30t/hm~2均可以达到较大节水潜力、肥料利用潜力、玉米经济效益,2015年和2016年净收益分别增加282.2～4534.7元/公顷,727.42～3057.44元/公顷。综上所述,膜下滴灌条件下适量的生物炭施用量和灌水量可有效改善土壤理化性质,提高作物各项生育指标,减少温室气体排放,有利于提高土壤肥料利用率,改善温室效应,提高经济效益,因此,适量施用生物炭和灌水对内蒙古地区农业经济发展和农业环境保护具有重要意义,其中,灌水下限-25kPa,生物炭施用量15t/hm~2和30t/hm~2可实现土壤质量有效提高、玉米增产和固碳减排的目标。
[Abstract]:The earth is our home to human survival, but in recent years, industrial, agricultural, rapid economic development, leading to overwhelmed our homes, the intensification of the greenhouse effect, climate change, continuous haze without to alarm us, protect the environment and protect the environment is agriculture has been urgent. Our source of energy intensive agriculture continued to increase while pressure, the number and intensity of chemical fertilizer increasing, soil compaction acidification, non-point source pollution problems such as increasing, and agriculture is one of the important sources of greenhouse gas emissions and impact should not be overlooked on the greenhouse effect, according to the domestic and foreign researchers have found that biological carbon in soil improvement and carbon sequestration and very fruitful. Therefore, in 2015 and 2016 respectively through field experiment in drip irrigation under mulch straw set Carbon fertilizer (0,15,30,45t/hm~2) and different irrigation water gradient (tensiometer the lower limit of irrigation: -35, -25, -15kPa), the research of water carbon (biochar) coupling on soil physicochemical properties, crop growth, yield and soil greenhouse gases (CO2, CH4, N20) influence of emissions, and increase comprehensive estimation the temperature potential of CH4 and N20 (GWP) and emission intensity (GHGI), in order to improve soil conditions in biochar, have certain effect to reduce greenhouse gas emissions, so as to find out the suitable biological carbon fertilizer and irrigation water, which not only provides a theoretical basis for the popularization and utilization of bio carbon in Inner Mongolia area at the same time, to promote the sustainable development of agriculture and ecological environment. The results are as follows: 1) study on the physicochemical properties of soil. Biochar significantly increased soil conductivity in different irrigation lower limit, and with biochar application amount increase The basic was firstly increased and then decreased; improve soil alkaline hydrolysis nitrogen, available potassium, the organic matter and available phosphorus content, high carbon, biological fertilizer with organic matter and available phosphorus increased the maximum; in the three leaf stage and jointing stage with biochar application rate increased soil temperature gradually increased after smoking male, in addition to biochar treatment 30t/hm~2, the other was lower than that of the control, the same biological carbon fertilizer, in the period with the increase of irrigation amount, the soil surface temperature decreased, growth period after the performance for W2W1W3, the irrigation lower limit -25kPa and biochar application amount of 30t/hm~2 is better to improve the water carbon composite soil surface temperature; basic biological carbon and irrigation water had no effect on soil pH; biochar amount of fertilizer can increase the soil water content in different irrigation quota under the 15t/hm~2 and 30t/hm~2 greatly To improve the soil moisture content.2) development and yield of maize growth. Irrigation and Fertilization on carbon were significantly increased during whole growth period of maize plant height, stem diameter, leaf area index (maize from jointing to maturity); biochar significantly increased the yield, harvest index, the effects of irrigation on Yield and harvest index were not significant; biological no significant effect of carbon on dry matter, irrigation quantity increased significantly in dry years the dry weight of corn, no significant effect in wet years; carbon water interaction on the crop index were not significant.3) of greenhouse gas emissions from farmland. The proper application of charcoal can effectively reduce the soil CO2 of corn farmland, and N20 the CH4 season cumulative emissions, thereby reducing the overall warming potential of Maize Soil CH4 and N20 (GWP), and ultimately reduce greenhouse gas emissions intensity (GHGI), more than 40% decline are considered, biochar added is 30t/hm~2 The appropriate biochar application amount of farmland, CO2, N20 and CH4 average season two years cumulative reduction in total emissions of 3016.81,0.46,0.31 kg/hm~2.4 respectively) fertilizer use efficiency and economic benefit. The water carbon coupling significantly increased nitrogen, phosphorus, potassium fertilizer utilization rate and economic benefit, the irrigation limit -25kPa, biochar application amount of 15t/hm~2 and 30t/hm~2 can achieve the great potential of water saving, fertilizer utilization potential and economic benefits of Maize in 2015 and 2016, net income increased 282.2 ~ 4534.7 yuan / ha, 727.42 ~ 3057.44 yuan / ha. To sum up, the amount of biochar under drip irrigation fertilizer and irrigation can effectively improve soil physical and chemical properties, improve the indexes of crop growth, to reduce greenhouse gas emissions, improve soil and fertilizer utilization rate, improve the greenhouse effect, improve economic efficiency, therefore, the amount of biochar and irrigation in Inner Mongolia Regional agricultural economic development and agricultural environmental protection are of great significance. Among them, the lower -25kPa of irrigation and 15t/hm~2 and 30t/hm~2 of biochar can achieve the goal of improving soil quality, increasing maize yield and fixing carbon and reducing emissions.

【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S275.6

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