黄河断流的成因与对策探析

黄河自1972年首次自然断流以来,断流频率逐渐增加,断流历时不断加长,断流时间逐步提前,断流河段不断上延,给沿黄地区特别是山东省的工农业生产造成了重大损失,严重影响了居民的生活。黄河断流的原因除近年的气候因素和黄河径流时空分布不均属自然因素外,沿河取水量逐年增加,用水管理不善等人为因素也是引起断流的重要原因。为此,对用工程的、管理的以及经济的方式治理黄河断流的可能性进行了探讨。     

黄河治理与排灌事业

西部大开发首当其冲的是贡河治理问题。文中论述了黄河流载的黄河治理、排灌事业、防止断流、节水农业四个问题。     

黄河断流与引黄灌溉发展之思考

黄河断流不是一个偶然现象,而是流域经济发展对水资源需求不断增长的必然结果,在今后长时间内将会继续存在。黄河断流为引黄灌溉发展带来了新的问题,即引黄水量受到限制,引水保证率降低。对此,应修改完善流域引黄灌溉发展规划,积极引进和推广节水新技术,加强引黄灌区多水源联合运用工程体系建设,重点发展补源灌溉,适当控制自流灌溉,以提高流域水资源调控能力和利用效率。     

黄河断流给引黄济青工程带来的困难与对策

对黄河断流的特点，现状进行了分析评价，阐述了克服黄河断流的必要性和迫切性，有针对性地提出了解决断流和确保工程持续发展的对策措施。     

节水农业技术发展综述

节水农业就是以节约农业用水为中心的农业，它是科学技术进步的产物，也是现代化农业的重要内涵。其核心是在有限的水资源条件下，通过采用先进的水利技术，适宜的农业技术和用水管理等综合技术措施，充分提高农业水利用率和水的生产效率及效益，保证农业持续稳定发展。节水农业技术包括渠道防渗、低压管道输水、喷、微灌等节水依溉技术、农田保蓄水技术、节水耕作和栽培技术，适水种植技术、节水管理技术以及与这些技术相应的节水新材料、新设备等。发展节水农业就是要不断提高灌溉水利用率、农田水分生产效率及效益。1水资源现状及对节水…     

甘肃省农业节水现状与发展建议

甘肃干旱少雨、水资源短缺,工农业及生态用水矛盾日趋突出。多年来,通过发展节水农业,缓解了水资源紧缺矛盾,提高了农业综合生产能力。但仍存在农业节水投入不足,科学合理的农业水价形成机制尚未建立,农业节水技术应用单一,适应市场经济体制要求的农业节水管理机制尚未形成等问题。今后一个时期甘肃省节水农业应通过进行流域综合治理,实现...     

黄河断流给引黄济青工程带来的困

对黄河断流的特点，现状进行了分析评价，阐述了克服黄河断流的必要性和迫切性，有针对性地提出了解决断流和确保工程持续发展的对策措施。     

国外节水农业发展动态

美国地貌、自然条件等方面与我国有诸多相似之处，其节水农业发展的经验可为我国借鉴。美国的农业节水主要采取旱作节水和灌溉节水协调发展的方式，灌溉面积约2670万hm^2，约占整个耕地面积的15％。其主要经验和做法有以下三个方面：     

浅议污水灌溉带来的问题及对策

近年来我国污水灌溉面积发展较快,但由于盲目灌溉引起严重后果。本文提出了由污水灌溉带来的一些问题及对策。分析指出,污水灌溉要因地制宜、合理规划、灌溉前要对污水进行处理,对水质进行实时监测,且引用污水中有害物质的含量不能超过所灌溉土壤的净化能力。同时,要结合当地水源情况,土壤质地,作物种植的种类及生长阶段等情况,因地制宜,合理地利用污水进行灌溉,这对缓解我国水资源日益紧张的供需矛盾,保护生态环境,提高     

我国农业可持续发展的水危机及广泛开展节水农业前景初探

通过对我国水资源状况及利用特征、不资源利用中存在问题的分析,结合国内外专家学者的意见,探讨了为实现我国农业可持续发展,深入广泛开展节水农业的前景。     

山西省发展农业节水灌溉的探讨

节水灌溉是解决山西省水资源短缺和促进农业可持续发展的有效途径.发展节水灌溉,可合理优化配置水资源、节约生产用地和能源,促进农业增产、农民增收和农村经济快速发展.本文就山西省农业节水灌溉的发展历程和当前存在的问题进行了探讨,并提出了有针对性的相应对策.     

农业高效用水及农艺节水技术

节水农业的中心问题是提高降水和灌水的利用效率,用水有效性无疑成为判断各种节水措施效果与潜力的标准。但用水有效性是一个相对概念,节水农业的标准也是比较型的,是与纵向和横向比较而言的,是可变的。随着科技的不断进步,节水措施的标准应该由有效用水向高效用水发展。高效用水农业就是高标准节水农业。就一个国家或一个地区而言,可以根据国情和地域情况制定一个节水农业的标准,如井灌区水的利用率为０７０,水的利用效率为１．２ｋｇ／ｍ３以上,可称为节水农业;水的利用率为０８５以上,水的利用效率达１．８ｋｇ／ｍ３以上…     

Assessing the groundwater dynamics and impacts of water saving in the Hetao Irrigation District, Yellow River basin

Water resources allocated to the agricultural sector in the Yellow River basin are being reduced due to severe water scarcity and increased demand by the non-agricultural sectors. In large-scale irrigation districts, the application of water-saving practices, e.g., improving the canal system, using water-saving irrigation technology and adjusting cropping patterns, is required for the sustainable agricultural development and the river basin environmental equilibrium. Adopting water-saving practices leads to lowering the groundwater table and to controlling salinity impacts related to excessive irrigation. However, assessing the effects of water-saving practices on the groundwater system requires further investigation. The Jiefangzha Irrigation Scheme of the Hetao Irrigation District is used as a case study for analyzing the temporal and spatial dynamics of the groundwater table. A lumped parameter groundwater balance model has been developed with this purpose and to assess impacts of various water-saving practices. The model was calibrated with monthly datasets relative to the non-frozen periods of 1997-1999 and validated with datasets from 2000 to 2002. Results indicate that canal seepage and deep percolation account for respectively 48% and 44% of the annual groundwater recharge. Groundwater discharge by direct evaporation and plant roots uptake represents 82% of the total annual groundwater discharge. After validation, the model was applied to assess the impacts of various canal and farm irrigation water-saving practices. It was observed that improvements in the canal system (e.g., canal lining, upgrading the hydraulic regulation and control structures, improving delivery schedules) might lower the groundwater table by 0.28-0.48 m, depending upon the level of implementation of these measures. Higher declines of the groundwater table are predicted when water-saving technologies are applied at both the canal and the farm systems. That decline of the water table favours salinity control and reduces capillary rise, thus reducing the groundwater evaporation and uptake by plant roots; that reduction may attain 128 mm. However, predictions may change depending on the way how water-saving measures are applied, which may be different of assumptions made; therefore, there is the need to perform a follow-up of the interventions in order to update predictions. Results indicate the need for appropriate research leading to improved irrigation management when the decline of the groundwater level will reduce groundwater contribution to vegetation growth.     

浅谈农业精确灌溉技术与设施

通过对我国目前水资源的状况、水资源利用中存在的问题，当今世界精确灌溉技术发展的现状及趋势进行分析，探讨精确灌溉技术及设施内容和未来发展前景。     

黄河谷地区域水资源开发利用及其取水水源论证

黄河谷地位于我国青海省东北部地区.古往今来,该地区由于其良好的地位优势、广阔的区域、丰富宝贵的水资源等自然条件,是人类居住生活、发展生产的不二之选.但就目前状况来看,受到经济条件的制约,黄河谷地这些优越的条件并未得到有效合理地开发利用.本文结合青海省水资源分布状况以及黄河谷地区域水资源特点,对该区域水资源开发利用及其取水水源做出了充分的论证,为加快黄河谷地水资源开发利用,使其早日摆脱贫困并为青海省建设贡献力量提出了参考依据.     

Assessing basin irrigation and scheduling strategies for saving irrigation water and controlling salinity in the upper Yellow River Basin, China

Water saving in irrigation is a key concern in the Yellow River basin. Excessive water diversions for irrigation waste water and produce waterlogging problems during the crop season and soil salinization in low lands. Supply control and inadequate functionality of the drainage system were identified as main factors for poor water management at farm level. Their improvement condition the adoption of water saving and salinity control practices. Focusing on the farm scale, studies to assess the potential for water savings included: (a) field evaluation of current basin irrigation practices and further use of the simulation models SRFR and SIRMOD to generate alternative improvements for the surface irrigation systems and (b) the use of the ISAREG model to simulate the present and improved irrigation scheduling alternatives taking into consideration salinity control. Models were used interactively to define alternatives for the irrigation systems and scheduling that would minimize percolation and produce water savings. Foreseen improvements refer to basin inflow discharges, land leveling and irrigation scheduling that could result in water savings of 33% relative to actual demand. These improvements would also reduce percolation and maintain water table depths below 1 m thereby reducing soil salinization.     

过滤后黄河水对滴灌系统的影响

为探明黄河水经孔径为0.05 mm(300目)过滤器过滤后进行滴灌的可能性,模拟大田滴灌研究了黄河水滴灌条件下4种滴灌带(Nf0.72,Nf1.60,Nf2.20,Dy1.38)不同位置流量变化规律,滴灌系统平均相对流量Q_r与流量变异系数C_v、系统均匀度C_u变化规律及相关关系.结果表明:黄河水对滴头的堵塞早期呈快速发育状态,不同类型引黄滴灌系统平均相对流量随灌水次数的增加呈平缓下降—快速下降—平缓下降的规律,均在相对流量75%附近快速下降;滴头流量变异系数在系统运行初期线性增大,之后平缓变化,且与系统平均相对流量具有很好的线性关系(p<0.001);当系统平均相对流量Q_r大于75%时,滴灌系统克里斯琴森均匀度系数C_u与Ln Q_r呈线性关系(R²=0.790 9),因此,引黄滴灌系统可通过系统平均相对流量Q_r来判断系统均匀度C_u,以方便及时快速了解系统堵塞状况,以便对其运行管理进行决策.     

浅析我国农业节水灌溉技术研究及进展

中国是世界上人均水资源占有量最贫乏的13个国家之一,水是农业的命脉,水资源的严重不足,使我国农业发展面临非常大的挑战.发展节水灌溉技术是我国未来农业发展的一项重大战略决策,也是坚持绿色发展理念的必然选择.为了解我国农业节水灌溉技术现状和研究进展,本文通过综合分析国内外节水灌溉技术现状,梳理我国目前主要的节水灌溉工程技术...