本文選題：蓄水坑灌　切入點(diǎn)：體系溫度　出處：《節(jié)水灌溉》2017年02期

【摘要】：通過(guò)研究體系溫度對(duì)蓄水坑灌施條件下土壤水分及氮素運(yùn)移轉(zhuǎn)化的影響,明確蓄水坑灌土壤水氮時(shí)空分布特征,探究土壤水氮運(yùn)移遷移轉(zhuǎn)化機(jī)理,以期為水肥合理灌施提供理論基礎(chǔ)。通過(guò)模擬構(gòu)建蓄水坑灌模型,以大型控溫箱精確控制土壤溫度,采用克里克空間插值法分析了蓄水坑灌條件不同體系溫度下的水分、硝態(tài)氮、銨態(tài)氮時(shí)空分布特征,結(jié)果顯示7 h左右土壤水分、養(yǎng)分完成入滲進(jìn)入再分布階段,土壤水分隨著時(shí)間的推移其垂向和徑向遷移距離均逐漸增大,同一時(shí)刻,溫度越高其橫向與徑向遷移距離越大,且靠近蓄水坑壁區(qū)域的土壤含水率相對(duì)越低;土壤中銨態(tài)氮含量在不同溫度下隨時(shí)間推移均呈現(xiàn)先增后減的現(xiàn)象,低溫下第15 d時(shí)土壤養(yǎng)分再分布核心區(qū)出現(xiàn)下降趨勢(shì),中、高溫第10 d時(shí)已出現(xiàn)下降趨勢(shì),且其遷移距離遠(yuǎn)低于水分、硝態(tài)氮的遷移距離;土壤中硝態(tài)氮含量在10℃下第10 d時(shí)出現(xiàn)增高現(xiàn)象,而20、25、35℃下第5 d時(shí)已出現(xiàn)增高現(xiàn)象,由蓄水坑周邊至濕潤(rùn)體邊緣呈現(xiàn)"低-高-低"的分布態(tài)勢(shì)。表明再分布階段溫度升高能提高水分的再分布速率,提高脲酶活性加快尿素水解轉(zhuǎn)化為銨態(tài)氮,同時(shí)促進(jìn)硝化反應(yīng)進(jìn)程抑制銨態(tài)氮在土壤中的積累,當(dāng)土壤含水量過(guò)高時(shí),會(huì)抑制土壤中氮素的硝化作用。
[Abstract]:By studying the effect of system temperature on soil water and nitrogen transport and transformation under irrigation and application in water storage pit, the spatial and temporal distribution of soil water and nitrogen was determined, and the mechanism of soil water and nitrogen migration and transformation was explored. In order to provide the theoretical basis for rational irrigation of water and fertilizer, the irrigation model of water storage pit was constructed by simulation, the soil temperature was accurately controlled by a large temperature control box, and the moisture under different system temperature was analyzed by using Crick space interpolation method. The temporal and spatial distribution characteristics of nitrate and ammonium nitrogen showed that the soil moisture was about 7 h, the nutrient infiltration entered into the redistribution stage, and the vertical and radial migration distance of soil moisture gradually increased with time, at the same time. The higher the temperature, the larger the distance between lateral and radial migration, and the lower the soil moisture content near the water storage pit wall, and the more the content of ammonium nitrogen in the soil increases first and then decreases over time. At the 15th day of low temperature, the core area of soil nutrient redistribution showed a downward trend, and the migration distance of soil nutrient at the 10th day of high temperature was much lower than that of water and nitrate nitrogen. The nitrate nitrogen content in the soil increased at 10 鈩，

本文編號(hào)：1684501