安达市灌溉用水需求与节水灌溉发展面积阈值分析

大力发展高效节水灌溉是现代农业可持续发展的必然选择。以黑龙江省安达市节水增粮行动为背景,分析了灌溉用水需求和节水灌溉发展面积阈值,结果表明:安达市节水增粮行动的水源主要为地下水,90%频率年的地下水可开采量6 759.84万m;1954-2014年作物需水量和净灌溉需水量都具有显著下降的趋势,近5a玉米的作物需水量为418.1mm,单位面积净灌溉需水量为101.4mm;节水增粮行动后地下水可开采量1 198.96万m~3,在水资源约束下的5种节水灌溉发展模式下(100%喷灌、90%喷灌+10%膜下滴灌、80%喷灌+20%膜下滴灌、70%喷灌+30%膜下滴灌、60%喷灌+40%膜下滴灌)可发展灌溉面积阈值分别为1.23、1.34、1.44、1.55和1.65万hm~2。     

我国高效节水灌溉技术的应用探析

介绍了我国农田有效灌溉面积现状,阐述了高效节水灌溉技术、喷灌应用情况,指出了灌溉效益与发展趋势。     

南水北调一期通水后海河流域平原区地下水修复研究

海河流域平原区地下水超采严重。南水北调工程通水后该区域水资源供给格局将发生较大变化,地下水超采情况有望得到缓解。以2020年为水平年,以水资源三级区为计算单元,分析南水北调通水后区域地下水开发利用与修复情况,以追求节约用水和修复地下水位为目标进行地下水调控。该研究对于发挥南水北调工程的巨大作用和促进海河流域平原区水资源的可持续利用具有指导意义。     

安徽淮北平原井灌几个问题的探讨

安徽淮北平原宜井灌溉面积占总耕地面积近80%。从该区井灌水量平衡分析入手，指出在一般干旱年份（P=75%）淮北平原井灌区的灌溉率（可灌面积/耕地面积）仅为54%左右，即使考虑短期超采，缺水率仍达23%；由于存在两类不均匀系数，井灌的实际可开采程度只有可开采地下水资源量的70%左右，考虑这一因素的影响，对井灌区的地下水资源量进行了校核，结果表明对于一次灌溉而言井灌区的地下水实际可开采量大于灌溉需水量，完全能满足灌溉开采的需求；同时，推荐了该区合理的机井数量、布井方式及井点密度，并就井灌工程建设和地下水的开发利用提出了几点建议。     

美国1985年的喷灌面积

根据美国《灌溉杂志》1986年第一期报导,美国1985年的喷灌面积为13460.62万亩,占总灌溉面积的37％。和1984年比较,喷灌面积在总灌溉面积中的比重增加了1％。但由于总灌溉面积下降了3％,所以喷灌面积绝对数也相应减少了0.7％。根据分析这主要是因东部雨量充沛地区减少了3％,而西部干旱的17个州仍增长了1％。     

美国灌溉现状分析

以１９９７年的美国灌溉统计资料为基础，结合近２０多年的数据，本文详细分析了美国的农田灌溉在近２０多年的发展状况，并从地理位置、气候类型和灌溉规模等不同角度全面分析了美国各种灌溉方法的构成、灌溉所用动力类型和灌溉农田上的作物结构。结果显示，近２０多年来，美国总灌溉面积中喷灌所占比例在不断增加，而地面灌溉比例则不断降低。１９９７的资料显示，在目前美国的灌溉面积中，喷灌是以中心支轴式系统为主，微灌以地表滴灌为主，而地面灌中则有３种类型的系统使用的较多。在灌溉农田的作物结构上，干旱地区的饲草类作物种植比例明显高于其它地区，而湿润地区的粮食作物、瓜果蔬类作物和棉花的比例较高。这种比例关系随分析的角度不同而有所变化     

当前喷灌发展中遇到的问题和解决途径

发展“两高一优”农业,实现２０００年的粮食增产目标,没有水不行。增加农业用水的供给,有开源和节水两条途径,开辟新水源投资较大,受到很多条件的限制,目前沧州市只能依靠大量开采地下水来维持工农业生产的发展。由于超量开采地下水,致使地下水位大幅度下降,深层水位年均下降１．５ｍ左右,浅层水位年均下降１．０～２．０ｍ。水资源的短缺,地下水位的下降带来了一系列环境生态的变化,在这种情况下,充分合理的利用现有水资源就有更为重要的意义,喷灌具有省水增产的突出优点,同时还能省工、省地、扩大灌溉面积、保持土壤结构、…     

他山之石

黑龙江省大力发展节水灌溉,今年计划新打机井2.1万眼,新增节水灌溉面积40万hm~2,进一步提高抗灾能力。 去年,黑龙江省投入打井、节水灌溉资金达7.31亿元,是历史上最多的一年。其中省、地、县投入7586万元,农民自筹4.02亿元,农行投入贴息贷款2.05亿元,大企业支援4800万元,当年新增节水点灌、白龙灌、喷灌、微滴灌面积达59万hm~2。齐齐哈尔地区大力发     

今日之美国灌溉

1980年美国灌溉总面积达3.7亿亩,在世界上仅次于中国与印度。同年其喷滴灌面积达1.2亿亩,居世界首位,约占其灌溉总面积之1/3。过去10年,美国灌溉面积与喷灌面积均有较大发展,灌溉面积增加6064万亩,喷灌面积增加6100     

美国灌溉的现状和展望

美国从1939年以来,灌溉面积稳步增长,1974年,灌溉面积约占耕地的18％,达247万公顷。因为大部分需要灌溉而又易于供水的地区差不多已完全发展了灌溉,所以予期农田灌溉面积的进一步扩大会放慢下来。日益增长的能源成本和有限的能源也阻碍喷灌面积     

Estimation of irrigation requirement for sustainable water resources reallocation in North China

The South-North Water Transfer (SNWT) project (upon completion) will deliver some 4.8 billion m³ of water per annum to Hebei, Beijing and Tianjin — greatly mitigating water shortage in North China. Surface water that is currently restricted to urban use could then become partly available for agricultural production. This will reduce the dependence of agriculture on groundwater, which will in turn retard groundwater depletion in the region. This study determines the spatial and temporal distributions of agricultural water requirement in Hebei Plain. This in turn lays the basis for surface water reallocation following the completion of the SNWT project. DSSAT and COTTON2K crop models are used along with crop coefficient methods to estimate required irrigation amounts for wheat, maize, cotton, vegetables and fruit trees in Hebei Plain. The study uses 20 years (1986-2006) of agronomic, hydrologic and climate data collected from 43 well-distributed stations across the plain. Based on the results, wheat accounts for over 40% of total irrigation water requirement in the plain. Similarly, wheat, maize and cotton together account for 64% of the total irrigation water requirement. The piedmont regions of Mount Taihang have the highest irrigation requirement due to high percent farm and irrigated land area. The months of April and May have the highest irrigation water requirement, respectively accounting for 18.1% and 25.4% of average annual irrigation. Spatial and temporal variations in our estimated irrigation water requirement are higher than those in the officially published statistics data. The higher variations in our results are more reflective of field conditions (e.g. precipitation, cropping pattern, irrigated land area, etc.). This therefore indicates a substantive improvement (in our study) over the average statistical data. Based on our simulation results, viable surface water reallocation strategies following the completion of the SNWT project are advanced and discussed.     

Irrigation modernization and water conservation in Spain: The case of Riegos del Alto Aragón

This study analyzes the effects of irrigation modernization on water conservation, using the Riegos del Alto Aragón (RAA) irrigation project (NE Spain, 123354 ha) as a case study. A conceptual approach, based on water accounting and water productivity, has been used. Traditional surface irrigation systems and modern sprinkler systems currently occupy 73% and 27% of the irrigated area, respectively. Virtually all the irrigated area is devoted to field crops. Nowadays, farmers are investing on irrigation modernization by switching from surface to sprinkler irrigation because of the lack of labour and the reduction of net incomes as a consequence of reduction in European subsidies, among other factors. At the RAA project, modern sprinkler systems present higher crop yields and more intense cropping patterns than traditional surface irrigation systems. Crop evapotranspiration and non-beneficial evapotranspiration (mainly wind drift and evaporation loses, WDEL) per unit area are higher in sprinkler irrigated than in surface irrigated areas. Our results indicate that irrigation modernization will increase water depletion and water use. Farmers will achieve higher productivity and better working conditions. Likewise, the expected decreases in RAA irrigation return flows will lead to improvements in the quality of the receiving water bodies. However, water productivity computed over water depletion will not vary with irrigation modernization due to the typical linear relationship between yield and evapotranspiration and to the effect of WDEL on the regional water balance. Future variations in crop and energy prices might change the conclusions on economic productivity.     

基于水盐生产函数的绿洲灌区水盐调控研究

土壤次生盐碱化是新疆灌溉农业所面临的最大环境问题。灌溉农业的快速扩展与灌排系统不完善是造成土壤次生盐碱化发生与恶化的关键因素。以水盐生产函数为依据,计算了不同生育阶段及全生育期阶段棉花相对产量与土壤全盐的关系,依据该计算结果对塔里木灌区的土壤盐化程度做了初步划分。基于塔里木灌区地下水埋深较浅且多为微咸水的事实,比较深入地探讨了地下水合理的动态水位及作物对潜水利用问题。最后,提出了灌区水盐调控的对策,强调排水系统的通畅运行是控制土壤次生盐碱化的关键,通过排水系统和减少灌溉定额使作物生长期的地下水埋深控制在1.6~2.1 m内,不但可以减少排水成本,而且也可使作物充分利用地下水,同时促进塔里木河水质的改善。     

Estimating hourly crop ET using a two-source energy balance model and multispectral airborne imagery

Efficient water use through improved irrigation scheduling is expected to moderate fast declining groundwater levels and improve sustainability of the Ogallala Aquifer. An accurate estimation of spatial actual evapotranspiration (ET) is needed for this purpose. Therefore, during 2007, the Bushland ET and Agricultural Remote Sensing Experiment (BEAREX07) was conducted at the USDA-ARS, in Bushland, Texas, to evaluate remote sensing (RS)-based surface energy balance models. Very high-resolution aircraft images were acquired using the Utah State University airborne multispectral system. Instantaneous ET was estimated using a two-source energy balance model (TSM). A minor modification was made in the calculation of sensible heat fluxes to improve ET estimation. Furthermore, a sensitivity analysis of selected variables was conducted to evaluate their effect on ET estimation. Data from four weighing lysimeters, planted to sorghum and corn, were used for evaluating ET predictions. Instantaneous ET was predicted with mean bias error and root mean square error of 0.03 and 0.07 mm h⁻¹ (4.3 and 11.7%), respectively. Results indicated that crop height, roughness length for momentum transfer, clumping factor and soil resistance sub-models need to be refined. Nevertheless, the application of the TSM using high-resolution RS imagery in the Southern High Plains is promising.     

平原井灌区地下水多年调节配水模型及其应用

华北平原纯井灌区水资源严重不足。限水灌溉是保持地下水平衡、农业可持续发展的必要条件,通过对作物耗水规律及地下水动态规律的分析,在保持地下水多年平衡的前提下,不追求个别年份高产,以多年粮食总产量最高为目标,提出了地下水均衡开采的调节配水模型,并采用非线性规划理论对该模型进行了论证。应用该模型可计算出不同水文年地下水开采量及各作物灌溉定额,进而计算灌溉制度,可广泛应用于纯井灌区的井灌工程的规划设计。     

Assessment of irrigation and environmental quality at the hydrological basin level: I. Irrigation quality

Irrigated agriculture notably increases crop productivity, but consumes high volumes of water and may induce off-site pollution of receiving water bodies. The objectives of this paper were to diagnose the quality of irrigation and to prescribe recommendations aimed at improving irrigation management and reducing the off-site pollution from a 15,500 ha irrigation district located in the Ebro River Basin (Spain). Three hydrological basins were selected within the district where the main inputs (irrigation, precipitation, and groundwater inflows) and outputs (actual crop's evapotranspiration, surface drainage outflows, and groundwater outflows) of water were measured or estimated during a hydrological year. The highest volume of water (I = 1400 mm/year) was applied in the basin with highly permeable, low water retention, flood irrigated soils where 81% of the total surface was planted with alfalfa and corn. This basin had the lowest consumptive water use efficiency (CWUE = 45%), the highest water deficit (WD = 5%) and the highest drainage fraction (DF = 57%). In contrast, the lowest I (950 mm/year), the highest CWUE (62%), and the lowest WD (2%) and DF (37%) were obtained in the basin with 60% of the surface covered with deep, high water retention, alluvial valley soils, where 39% of the cultivated surface is sprinkler irrigated and with only 48% of the surface planted with alfalfa and corn. We concluded that the three most important variables determining the quality of irrigation and the volume of irrigation return flows in the studied basins were (i) soil characteristics, (ii) irrigation management and irrigation system, and (iii) crop water requirements. Therefore, the critical recommendations for improving the quality of irrigation are to (i) increase the efficiency of flood-irrigation, (ii) change to pressurized systems in the shallow and highly permeable soils, and (iii) reuse of drainage water for irrigation within the district. These management strategies will conserve water of high quality in the main reservoir and will decrease the crop water deficits and the volume of irrigation return flows, therefore, minimizing the off-site pollution from this irrigation district.     

中国喷灌机现状与发展思考

基于水利统计数据,分析了近10 a中国节水灌溉应用分布,发现东北以喷灌为主,西北以微灌为主,华北以低压管灌为主,华东以渠道灌溉为主,具有明显的区域特征,节水灌溉仍有50%发展空间,喷灌技术占比与欧美国家相比仍然偏低.总结回顾了中国喷灌机发展历程、研究进展和发展趋势.从国家政策引导、智慧农业发展、农业种植结构变化和盐碱地耕地改造4个方面,分析了在资源环境约束挑战下中国喷灌机的发展机遇.阐明了喷灌的优势和不可替代作用,指出随着中国高标准农田建设及农业规模化经营稳步推进,喷灌机性能及功能不断增强,使以往喷灌的局限性逐步转变成发展优势.最后从补齐农业全程机械化短板、水肥药一体化作业新模式和无人化智能化方面展望了中国喷灌机未来发展前景.     

大型水稻灌区高产节水灌溉优化配水模型研究

根据江苏省北部地区水资源供需矛盾突出的现状,以大型水稻灌区为研究对象,研究水资源的优化分配问题,从水稻水分生产函数和作物需水模型入手,建立了外引河湖水、内提回归水两种水源供水条件下的水稻全生育期适时调度优化配水数学模型。以灌区典型年供水资料,对优化配水模型进行了复核验证。所建立的模型,与灌区实际用水条件基本相符,为水稻灌区用水管理提供了一条新路。     

Flexible delivery schedules to improve farm irrigation and reduce pressure on groundwater: a case study in southern Italy

This study was conducted on an irrigated area of southern Italy to analyze the current operation of a large-scale irrigation delivery system and the effects of the operation procedures on crop irrigation management and aquifer salinity increase. The area is characterized by relatively high levels of groundwater salinity in the summer that are probably due to intensive groundwater pumping by farmers during periods of peak irrigation demand, with the resulting seawater intrusion. Two alternative delivery schedules, namely the rotation delivery schedule and the flexible delivery schedule, referred to as RDS and FDS, respectively, were simulated using a soil-water balance model under different combinations of crop, soil and climatic conditions. The first set of simulations concerned the farm irrigation management constrained by the rotational delivery used by the local water management organization. The second scenario simulated the farm irrigation schedule most commonly used by growers in the area for maximizing crop yields. Based on crop irrigation management under RDS and FDS, two alternative operational scenarios were also developed at the scheme level and then compared for evaluation. Winter and summer salinity maps of the aquifer were developed by interpolating salinity measurements of the groundwater samples collected during the 2006 irrigation season. From these maps, a close relationship can be inferred among delivery schedule, aquifer exploitation and salinity increase, which justifies the need for implementing FDS that might reduce the groundwater demand for irrigation.