农业灌溉试验的灌溉水量调节技术研究

为解决常规农业灌溉水量调节技术面临的耗水量过多问题,实现绿色灌溉,设计了一种新的农业灌溉水量调节技术。该技术通过优化配置灌溉水资源,计算农业灌溉总需水量,设计灌溉水量调节优化方案,实现了农业灌溉水量调节。实例分析结果表明,应用农业灌溉水量调节技术能够降低不同灌溉区域的灌溉耗水量,证明设计的农业灌溉水量调节技术的调节效果较好,具有一定的应用价值,可为后续农业灌溉方案的制定提供参考。

基于遥感ET数据的区域水资源状况及典型农作物耗水分析

以遥感ET及实测降水数据为基础,借助GIS技术开展水分盈亏分析研究;同时依据项目区土地利用现状,选择冬小麦、夏玉米、棉花及人工草坪为重点分析对象,对其耗水及灌溉耗水规律进行研究。结果表明:①大兴区耗水量与降水量在总量上不平衡,时空上不匹配,在现状土地利用下若无外来水补充,则不得不超采地下水,资源型缺水突出。②冬小麦和夏玉米耗水年际变化不大,而棉花及人工草坪随降水增加耗水增大;分析作物耗水与降水的吻合性发现,冬小麦耗水与降水匹配性最差,其次为人工草坪,而夏玉米及棉花耗水与降水匹配较好。③在所选择的4种作物中小麦灌溉耗水量最大,达230 mm以上;其次为人工草坪,其灌溉耗水量超过189 mm;夏玉米及棉花灌溉耗水量较小。

还原水量的分项估算

各种人类活动所引起的水文效应,以不同的途径改变着河川径流,对流域中各项影响因素所造成的水量变化逐一调查、观测加以定量。

盘锦市稻田水分生产率及水分生产函数研究

为寻找提高灌溉水分生产率的途径和突破口,采用统计资料、卫星遥感数据和地面气象数据相结合的方法,计算了2005—2013年间盘锦市稻田面积上水稻生育期内的有效降水量、蒸发蒸腾量、各年稻田的总灌溉耗水量,以及稻田蒸发蒸腾水分生产率和灌溉水分生产率,并建立以地级市为单元水稻水分生产函数。结果表明,近9年来盘锦稻田蒸发蒸腾和灌溉水分生产率年平均值分别为2.718、1.170kg/m^3;水稻生育期内的年平均蒸发蒸腾量为341.2mm,年有效降水量为139.3mm,年平均灌溉耗水量为720.4mm,有效降水对蒸发蒸腾量的贡献率为40.8%,灌溉对蒸发蒸腾量的贡献率为59.2%;修正的Jensen模型适合于盘锦市多年间稻田面积上"作物-水分"关系表达,统计值和模拟值线性关系显著,7月份敏感指数最小,9月份敏感指数最大。本研究旨在为区域稻田蒸发蒸腾量不同水分来源的构成分析及Jensen模型在区域中的应用提供思路和借鉴。

基于植被遥感信息的作物蒸散量估算模型——以华北平原冬小麦为例

本文基于作物系数法并结合植被遥感信息(MODIS/NDVI),提出一种能反映作物空间分布和土壤供水差异信息的作物蒸散量估算模型。利用该模型得到2000—2013年华北平原冬小麦的蒸散量,模拟结果与遥感蒸散产品吻合度较高(R2=0.952,RMSE=1.3×107 m3),并分析了冬小麦蒸散量和灌溉耗水量的时空变化。结果表明:1华北平原冬小麦蒸散量呈南高北低的格局。基于250 m空间分辨率上来看,山东省、河南省的黄河灌区以及太行山前平原的冬小麦蒸散量可达400 mm以上,中部平原区冬小麦蒸散量<350 mm,滨海一带蒸散量<200 mm。2冬小麦灌溉耗水量与其蒸散量格局相一致。在太行山前平原、河南省和山东省的引黄灌区,灌溉耗水量可达250 mm以上;河北平原北部由于冬小麦种植比例较低,灌溉耗水量<100 mm。3近14年河北平原北部冬小麦播种面积下降明显,区域灌溉耗水量减少,地下水位下降趋势得到明显缓解。本文提出的作物蒸散量估算模型能够较好地用于确定较大区域作物蒸散耗水量,并可应用于区域作物灌溉量的评估与管理中。

Effects of Irrigation Quantity and Term on Waterconsumption and Yield of Winter Wheat by Wide Precision Sowing

[Objective] The aim was to research effects of irrigation quantity and term on winter wheat by wide precision sowing and to provide references and technical supports for water-saving agriculture in North China. [Methed] During 2013-2015, Jimai 22, a winter wheat cultivar, was taken as materials to explore effects of irrigation quantity and term on water consumption characters and yield of winter wheat by wide precision sowing. [Result] As irrigation water increased, water consumption and irrigation water＇s proportions were growing, but quantity and proportion of soil water consumption were both diminishing; seed yields all kept increasing upon irrigation, but water use efficiencies were decreasing. Given the same irrigation conditions, water consumption by wide precision sowing was more, but yield and water use efficiency were higher. [Conclusion] The practice of combining wide precision sowing and irrigation in jointing and flowering stages, based on yield, water use efficiency and economic profits, has the potential to create more yields and higher water use efficiency and suitable to be applied and promtoed in North China.

Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Dripirrigated Celery

This study aimed to investigate the effects of different irrigation amounts on water consumption and water use efficiency of celery under the condition of drip irrigation, so as to provide a scientific basis for high-yielding, high-quality and highefficiency cultivation and water-saving irrigation of greenhouse celery. Total five irrigation amounts were designed, 117.5 （T1）, 160.0 （T2）, 202.5 （T3）, 245.0 （T4） and 287.5 （CK） mm/hm2, and the effects of different irrigation amounts on yield, water consumption and water use efficiency of celery were studied by plot experiment. The results showed that at the soil depth of 0-40 cm, the soil water storages of different treatments ranked as T3＇s〉T4＇s〉CK＇s〉T2＇s〉T1＇s, and the celery water consumptions ranked as CK＇s〉T4＇s〉T3＇s〉T2＇s〉T1＇s. At the same time, the soil water storage in different treatment group declined with the growth of celery, and finally increased at the harvest period. Among different irrigation amounts, the water use effi- ciency and irrigation water use efficiency all ranked as T1＇s〉T2＇s〉T3＇s〉T4＇s〉CK＇s. The water consumption of celery was positively related to irrigation amount （P〈 0.01）, and was negatively related to water use efficiency （P〈0.01） and irrigation water use efficiency （P〈0.05）. When the irrigation amount was below 253 mm/hm2, the celery yield was positively related to irrigation amount （P〈0.01）. There was also a positive correlation between celery output and irrigation amount. Compared with those of CK, the benefit of the T4 treatment group was equal, and the water consumption was reduced by 14.78%. In high-efficiency solar greenhouse, the irrigation amount of drip-irrigated celery is recommended as 245 mm/hm2.