【作者】 郭金强；

【导师】 危常州；

【作者基本信息】 石河子大学 ， 作物栽培学与耕作学， 2005， 硕士

【摘要】 膜下滴灌是当今世界最先进的节水灌溉技术和覆膜栽培技术相结合的产物,同传统的灌水方式和栽培技术相比较具有节水、高产、优质和高效的优点。在覆膜和滴灌的综合效应下,土壤水肥环境以及作物的生长与常规条件不同,作物需水、需肥规律都发生了变化。然而棉花膜下滴灌在水氮管理上表现出很大的盲目性。本文以棉花为研究对象,在田间调查的基础上,从水氮耦合的角度重点探讨水氮耦合效应对棉花膜下滴灌地上部分生物学特性及其产量的影响,进而研究了棉花需水、需氮规律,得出以下主要结论: 1.棉花膜下滴灌蒸散量受灌溉量影响较大,随着滴灌量的增加棉花耗水量也逐渐增加。播种到出苗耗水量为5.80mm,苗期后1～23d耗水量为37.3mm,出苗后24～60d耗水量为113.3mm,出苗后61～112耗水量为237.5mm,出苗后113～157d耗水量为40.0mm,全生育期耗水量为433.7mm 2.滴灌棉田吸氮高峰期在出苗后60d(初花期,6月30日前后)至100d(盛铃期,8月10日前后)的39d内,吸氮量占全生育期氮总积累量的70%以上,表明膜下滴灌棉花将大部分氮肥以追肥分配给棉花是符合棉花养分需求的生理规律的。在本试验中通过对N2处理棉花氮素积累的汇总得出:膜下滴灌棉田在出苗后60～100d棉花吸氮量为206kg/hm~2,其中出苗后61～70d吸氮为54kg/hm~2,71～80d吸氮量为60kg/hm~2,81～91d吸氮量为54kg/hm~2,92～101d吸氮量为38kg/hm~2。 3.建立了棉花水氮耦合方程,计算得在本试验中籽棉产量达到5253kg/hm~2.最佳灌溉量和施氮量分别为4190m~3/hm~2、224kg/hm~2。 4.通过分析水氮对棉花产量构成因子的影响,结果表明施氮量是影响棉花产量的主导因素,表现高产的主要原因是因为高氮处理单铃重明显高于低氮处理。较高的灌水量可获得较大的产量和生物量,但水分生产效率和水分干物质生产率低于中水量处理。更多还原

【Abstract】 Drip irrigation underfilm mulch is an advanced technique combined by the trickle irrigation technique and the polyethylene film planting technique, which have the advantages of saving water, enhancing yields, upgrading quality of product and high water utility. Compared with conventional irrigation and cultivation mode, the soil moisture and fertile environment, water-nitrogen requirement pattern are changed by drip irigation under film mulch. However, The mechanism of these advantages is not awared till now, A coupled irrigation plus fertilization experiment was conducted to explore the impact on biological characteristics and cotton yield in term of water-nitrogen coupling. The demonic of cotton plant’s nitrogen uptake and apparent evapotranspiration under film mulch and drip irrigation was studied as well. The main results were as follows:1. Apparent evapotranspiration of cotton field in different growth stages was strongly influenced by irrigation quota. With the increase of the quota of irrigation the cotton plant water consuming capacity is increased as well.The average apparent water consuming capacity is 5.8mm from planting to emergence, 37.3mm in days after emergence 24, 113.3mm in days after emergence 24 to 60, 237.5mm in days after emergence 61 to 112,40.0mm in days after emergence 113 to 157 respectively, the whole water consuming capacity in cotton whole life cycle was 433.7mm in the condition of film mulch and dip irrigation.2. Nitrogen uptake was appear in days after emergence 60 (earlier flowering, about 30, June) to 100 (full boiling about 10, August) 39days, whereas over 70% nitrogen was absorbed during this period. This suggested that it is reasonable to distribute most of the nitrogen fertilizer in form of top-dressing would fit to cotton physiological demands. Our results illustrated that nitrogen absorbed 206kg N/hm~2 during 60-100 days after emergence, thereinto 54 kg N/hm~2 was absorbed days after emergence 61 to70, 60 kg N/hm~2 was absorbed days after emergence 71 to 80, 54 kg N/hm~2 was absorbed days after emergence 81 to 92, 38 kg N/hm~2 was absorbed days after emergence 71 to 80 respectively.3. An emperical model between cotton yield and irrigation/fertilization was established, we calculated that the maximum yield was 5253kg/hm~2, the maximum yield irrigation was 4190m~3/hm~2, and the maximum yield N application was 224 kg/hm~2.4. Yield composition factor analysis demonstrated that nitrogen fertilization is the main factor that affected cotton yield, the mechanism was higher nitrogen fertilization could yield bigger boll as compared to lower nitrogen fertilization, higher irrigation quota could yield higher economic yield and biomass as compared to lower irrigation quota. While water product efficiency and water usage efficiency was lowed.更多还原