西北旱区制种玉米父本母本耗水特性及蒸发蒸腾量估算方法研究

发布时间：2018-04-14 13:17

  本文选题：蒸发蒸腾量 + 耗水特性　； 参考：《中国农业大学》2016年博士论文

【摘要】：理解农田土壤-作物系统水分传输机制以及选取适当方法对农田蒸发蒸腾量(E7)进行估算,是国际水科学研究的前沿和热点问题。针对我国西北旱区水资源极度短缺的现状,本文选取西北旱区制种玉米为研究对象,于2012-2014年以涡度相关系统、茎流计、自动气象站和土壤水分监测系统为基础开展田间水分传输综合观测,探索了制种玉米父本母本耗水特性,建立了ET及其组分的估算模型。取得了如下主要成果：(1)揭示了制种玉米父本和母本在各生育期内植株形态及生理特性的差异性,探讨了父本母本液流变化的差异及影响因子。试验期间,母本液流速率明显高于父本,2013和2014年最大差别分别为0.33和0.28 L d-1。小时尺度的父本母本液流速率主要受净辐射、光合蒸腾速率及气孔导度影响,日尺度液流速率与净辐射、土壤含水量和叶面积指数密切有关,与株高相关性不显著。父本日尺度的液流速率还与茎粗线性相关。(2)明确了制种玉米尺度转换因子,探讨了制种玉米ET变化规律和特征。采用叶面积、茎粗和密度为尺度转换因子对单株液流进行尺度提升,与涡度相关实测的日尺度ET (ETEC)相比,以茎粗和密度为尺度转换因子得到的日尺度ET在两年试验阶段均明显高于ETEC。采用叶面积为尺度转换因子得到的ET在所测阶段与ETEC有较好的一致性。全生育期内三年的ET分别为479.75、373.92和401.30mm；总的蒸腾量(Ts)分别为424.75、315.54和321.95mm,母本的蒸腾量明显高于父本的蒸腾量,且母本蒸腾量占Ts的比例达63-80%；总的土壤蒸发(E)分别为55.00、47.77和62.21mm,E占ET的比例分别为11%、13%和16%。制种玉米的作物系数(Kc)在整个生育期内呈现出单峰曲线,三年全生育期平均Kc分别为0.78、0.79和0.73。(3)分析了不同冠层覆盖度下制种玉米ET及Kc的变化规律,构建不同冠层覆盖度下蒸发蒸腾量估算模型。在种植密度范围内,全生育期的ET及Kc随密度的增加而增加,而E随密度的增加而减小。为了估算不同种植密度下的ET,引入密度比(K-density)修正了作物系数法,K-density为LAI的函数(K-density方法)。与考虑调整系数(Acm)的Allen方法、引入密度系数(Kd)的单作物系数(Kcm方法)和双作物系数法(Kcb方法)相比,Kdensity方法在全生育期均与实测值较为接近。(4)提出了考虑冠层覆盖度(f)变化及父本母本差异的冠层阻力组合方法,构建了基于有效阻力的P-M模型。与实测的有效表面阻力(rcec)相比,在f=1时,采用并联的方法组合rcm和rcf得到的有效表面阻力与rcec有很好的一致性；当f1,rcm,rcf和rss采用以覆盖度为权重因子的并联方法组合得到的有效表面阻力两年均明显高于rcec。而采用基于LAI为权重因子的并联方法与实测值较为一致。与最初的单层模型相比,基于两种有效阻力计算方法的P-M模型的估算值更接近实测值,尤其是采用LAI为权重因子的考虑作物和土壤阻力并联的组合方法。(5)分析了考虑父本母本混种及土壤多组分组合的作物系数法和基于相邻作物光能截获划分模型的多源模型的应用效果,实现了制种玉米ET较精确的划分。与作物系数法相比,采用多源模型模拟的ET、父本母本蒸腾值(乃及E两年均与实测值较为一致,而作物系数法模拟的ET,父本母本T及E均高于实测值。
[Abstract]:To understand the soil crop system of water transport mechanism and selects the appropriate method for the farmland evapotranspiration (E7) estimation is the frontier and hot issues of international water science. According to the present situation of severe shortage of water resources in northwest arid region of our country, this paper selected for Maize in northwest arid region as the research object, in 2012-2014 years by the vorticity the related system, stem flow gauge, automatic weather station and soil moisture monitoring system based on field water transmission comprehensive observation, explore the maize seed parents water consumption characteristics, set up a model to estimate the ET and its components. The main results are as follows: (1) revealed the differences between the male and female seed corn in different growth during the period of morphological and physiological characteristics, discusses the difference of paternal parent flow and influence factors. During the test, each parent was significantly higher than that of liquid flow rate, and the maximum difference in 2014 2013 Don't were mainly affected by the net radiation parents liquid 0.33 and 0.28 L d-1. hour scale flow rate, photosynthetic rate and stomatal conductance influence on scale sap flow rate and net radiation, closely related to soil moisture and leaf area index, and were not significant. The high correlation between the liquid flow rate on the scale of the male parent with stem diameter correlation. (2) the corn seed production scale conversion factor of maize seed ET variation and characteristics. The leaf area, stem diameter and density scaling factor scale to enhance plant sap flow, and ET scale eddy correlation measurement (ETEC) compared with stem the coarse and density on scale ET scale conversion factor obtained in two trials were significantly higher than that of ETEC. by leaf area scale conversion factor obtained by ET are consistent in the test stage and ETEC ET for three years. During the whole growth period were 479.75,37 3.92 and 401.30mm; the total evapotranspiration (Ts) were 424.75315.54 and 321.95mm, transpiration transpiration was significantly higher than that of female male and female, transpiration accounted for the proportion of Ts was 63-80%; the total soil evaporation (E) were 55.00,47.77 and 62.21mm, E ET ratio was 11%, the 13% crop coefficient 16%. and corn (Kc) showed a single peak curve in the whole growth period, the average Kc three years in the whole growth period were 0.78,0.79 and 0.73. (3) analysis of the variation of different canopy coverage of maize ET and Kc, construct the estimation model of evapotranspiration of different canopy coverage in planting density. Within the range of ET and Kc in the whole growth period increased with the increase of density, while E decreases with the increase of density. In order to estimate the different densities of ET, the density ratio (K-density) modified crop coefficient method, K-density as a function of LAI (K-density). With the consideration of the adjustment coefficient (Acm) of the Allen method, introducing the density coefficient (Kd) of the single crop coefficient (Kcm) and dual crop coefficient method (Kcb method) compared to the Kdensity method in the whole growth period and the measured value is close to. (4) considering the canopy coverage (f) canopy resistance method of differentiation and paternal parent, P-M model is constructed based on the effective resistance. And the effective surface resistance test (RCEC) than in the f=1, the effective surface resistance and RCEC obtained by the method of combining RCM and RCF in parallel with good consistency; when F1, RCM, RCF and RSS by the effective surface resistance to get coverage as a combination of two parallel method of weight factors were significantly higher than that of rcec. and LAI based on parallel method for weighting factor accord with the measured values. Compared with the original single model, P-M model calculation method based on the two kinds of effective resistance The estimation values are close to the measured values, especially the use of LAI combination method considering crop and soil resistance parallel weight factor. (5) based on the analysis and application of multi-source model of the adjacent crop light interception partition model considering the crop coefficient of different combinations of male plants and soil mixed groups, which can realize the accurate corn seed ET. Compared with the crop coefficient method, the multi model simulation of ET, each parent value is E and transpiration (two years were similar, and the simulation of crop coefficient of ET, T and E male plants were higher than the measured value and the measured value.

【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S513
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本文编号：1749479