桓台县的节水灌溉管理技术

管理技术是灌溉节水的重要因素之一,直接关系到水的利用率。由于我国节水农业的管理水平较低,制约了节水农业的发展,针对此问题,桓台县依法治水、管水、用水,使农业用水的利用率达到了０ ．８６ ～０ ．９３ ,水分生产率达１ ．８３～２ ．０２ ｋｇ／ｍ ３,成为我国农业高效用水的典范     

低压管喷及其节水高产机理研究

通过在中国农科院商丘试验区实施低压管喷，结合麦棉套种作物需水特点、农田小气候相互关系进行了农业高效用水研究与实践，揭示出低压管喷麦田连续畦灌水４５％－４７％，棉田较连续灌灌节水４３％，小麦和棉花水分生产效率达１．８８－１．９５ｋｇ／ｍ＾３和０．３２ｋｇ／ｍ＾３较高水平的节水高产机理。     

节水农业是提高用水有效性的农业

节水农业是提高用水有效性的农业，它包括节水灌溉农业和旱地农业，应针对我国水的利用率、作物水的利用效率低和农业用水管理水平低的现状，来提高我国的农业用水有效性。采取农业与水利结合发展节水农业。     

21世纪中国粮食安全和对水的需求与对策

目前中国粮食安全水平高于日本、俄罗斯、印度和世界平均水平,到２１世纪可能下降。中国人多、地少、水缺,进口部分粮食是必然的,就是粮食自给率降到９０％,也主要是自己养活自己。２０３０年中国人口可能达到１５．３～１６．３亿人,粮食需求６．４５～７．２０亿ｔ,灌溉面积要发展到０．６３亿ｈｍ２,一般用水量要增加２０００亿ｍ３以上。在中国农业用水危机的现实下,如何保护粮食安全,根据资源和技术潜力以及国内外的典型经验,有能力克服和采取的对策是：①全面节水重点是农业节水,提高农业用水效率和利用效率;②全面节水增援工业和生活用水,减轻农业用水压力;③充分利用降水发展节水、增产高效的旱地农业;④加强管理和科技投入,出新成果、大成果,在农业用水危机中保护粮食安全。     

节水农业是提高用水有效性的农业

节水农业是提高用水有效性的农业，它包括节水灌溉农业和旱地农业。应针对我国水的利用率、作物水的利用效率低和农业用水管理水平低的现状，来提高我国的农业用水有效性。采取农业与水利结合发展节水农业。     

花生玉米间套种植的节水增收效益

豫北临黄河故道的轻砂壤土质地区,花生为当前秋季的主要种植作物。以节水高效为目的,１９９７年在新乡县古固寨镇节水试验示范区对花生、玉米间套种植的技术和效益进行了探索。结果说明,采取适宜的节水农业技术措施,花生和玉米产量分别达５３２．１ｋｇ及３０９０．０ｋｇ,其产值为２０２６８．４５元／ｈｍ２,水分生产效益达４．２８元／ｍ３。充分显示出了立体间套种植的节水、高效优势。     

花生玉米间套种植的节水增收效益

豫北临黄河故道的轻砂壤土质地区,花生为当前秋季的主要种植作物。以节水高效为目的,１９９７年在新乡县古固寨镇节水试验示范区对花生、玉米间套种植的技术和效益进行了探索。结果说明,采取适宜的节水农业技术措施,花生和玉米产量分别达５３４２．１ｋｇ及３０９０．０ｋｇ,其产值为２０２６８．４５元／ｈｍ２,水分生产效益达４．２８元／ｍ３。充分显示出了立体间套种植的节水、高效优势。     

寒地水稻节水灌溉研究

根据水稻发育过程中对水分反应的遗传性理论，经过试验研究，提出在寒冷地区气候条件下，以浅水层淹灌为主，晒田（中干）湿润相结合的浅湿型节水灌溉基本模式。在高产和维持相同产量前提下，直播水稻生育期灌水量６６７６．９５ｍ３／ｈｍ２，节水１９．６％，水的生产效率为０．９７ｋｇ／ｍ３；“旱育稀植”水稻：厚土层本田灌水量２２９９．５０ｍ３／ｈｍ２，节水５９．２％，水的生产效率为３．３７ｋｇ／ｍ３；薄土层本田灌水量４７８２．００ｍ３／ｈｍ２，节水４６．６％，水的生产效率为１．５４ｋｇ／ｍ３，在节水灌溉方面，达到北方寒冷稻区先进水平。     

农业节水灌溉的财政经济效益分析研究——评《节水农业经济分析》

节水农业是提高用水有效性的农业,是水、土、作物资源综合开发利用的系统工程。衡量节水农业的标准是作物的产量及其品质,用水的利用率及其生产率。节水农业包括节水灌溉农业和旱地农业,节水农业最基本的内涵特征是高效利用水资源,高效包括提高水资源的“有效性”和“转化效率”2个方面,节水农业包括4个方面的内容:一是农艺节水,二是生理节水,三是管理节水,四是工程节水。     

关于黄河流域农业节水问题

１　渠系配套提高水的利用率１９９８年７月随中科院地学部考察黄河断流问题,考察了４个灌区。山东打渔张灌区的渠系水的有效利用率为０．５,田间水利用率０．５,灌溉水利用率０．２５;河南人民胜利渠灌区年引黄河水６亿ｍ３,灌溉４００００ｈｍ２,灌溉水利用率０．４;陕西泾惠渠灌区９００００ｈｍ２,年引泾河水４亿ｍ３,灌区内有机井１．３万眼,实行井渠双灌,灌溉水的利用率为０．５０５;宁夏青铜陕灌区灌溉水的利用率０．２１。还有些配套程度差的灌区,水的利用率更低。引黄灌区多在５０～７０年代修建的。许多工程只建了渠…     

水资源水质水量优化配置分析

本研究旨在实现水资源水质水量的优化配置,通过对水资源水质水量优化配置的生态经济学理论进行分析,指出水资源水质水量优化配置的概念,在内涵分析基础上确定了水资源水质水量优化配置的具体阈值原理和模型体系框架.同时对青海水资源水质水量的优化配置进行分析,指出不同区域的水资源水质水量需要进行针对性的优化配置.     

水资源管理中水量水质联合调控的模式探讨

在水资源管理中,水量水质联合调控主要是为了协调生态环境.利用运筹学、系统方法论、宏观经济学为计算基础,通过控制流域污染物来达到水质控制的目标.基于此,本文对水资源管理中水量水质联合调控的模式进行探讨.     

浅析传统水利向环境水利及生态水利的转变

农田水利建设一直是我国农业发展的重中之重,最初的农田一般仅依靠自然河水和雨水进行灌溉,而后由兴修的水利工程进行灌溉,农水建设发展到今天开始重视环境水生态.传统农田水利向环境水生态转变是一种必然的发展趋势.这种形式的转变能够最大限度地满足农业经济发展中的用水需求,而且不会对生态环境带来危害.本文主要分析农田水利发展对环境的影响,并概述了传统农业水利向环境水生态转变的过程.     

Sugarcane water use from shallow water tables: implications for improving irrigation water use efficiency

The resource potential of shallow water tables for cropping systems has been investigated using the Australian sugar industry as a case study. Literature concerning shallow water table contributions to sugarcane crops has been summarised, and an assessment of required irrigation for water tables to depths of 2 m investigated using the SWIMv2.1 soil water balance model for three different soils. The study was undertaken because water availability is a major limitation for sugarcane and other crop production systems in Australia and knowledge on how best to incorporate upflow from water tables in irrigation scheduling is limited. Our results showed that for the three soils studied (representing a range of permeabilities as defined by near-saturated hydraulic conductivities), no irrigation would be required for static water tables within 1 m of the soil surface. Irrigation requirements when static water tables exceeded 1 m depth were dependent on the soil type and rooting characteristics (root depth and density). Our results also show that the near-saturated hydraulic conductivities are a better indicator of the ability of water tables below 1 m to supply sufficient upflow as opposed to soil textural classifications. We conclude that there is potential for reductions in irrigation and hence improvements in irrigation water use efficiency in areas where shallow water tables are a low salinity risk: either fresh, or the local hydrology results in net recharge.     

水利工程项目的水闸设计探讨

在水利工程项目建设中,水闸工程项目占据着极其重要的作用.换言之,水闸工程质量的好坏,在很大程度上将直接关乎到整个水利工程项目的整体效果,包括使用寿命、功能发挥等.在工程建设过程中,水闸这一环节一旦出现了问题,对于整个工程及其下游地区,都会造成安全隐患,极大危害着当地居民的财产与生命安全.本文重点针对水利工程项目中的水闸设计环节,选取了春风河水利工程项目实例探讨,着重以该工程的水闸设计为研究对象,加以论述.     

Non-conventional water resources and opportunities for water augmentation to achieve food security in water scarce countries

Given current demographic trends and future growth projections, as much as 60% of the global population may suffer water scarcity by the year 2025. The water-use efficiency techniques used with conventional resources have been improved. However, water-scarce countries will have to rely more on the use of non-conventional water resources to partly alleviate water scarcity. Non-conventional water resources are either generated as a product of specialized processes such as desalination or need suitable pre-use treatment and/or appropriate soil–water–crop management strategies when used for irrigation. In water-scarce environments, such water resources are accessed through the desalination of seawater and highly brackish groundwater, the harvesting of rainwater, and the use of marginal-quality water resources for irrigation. The marginal-quality waters used for irrigation consist of wastewater, agricultural drainage water, and groundwater containing different types of salts. In many developing countries, a major part of the wastewater generated by domestic, commercial, and industrial sectors is used for crop production in an untreated or partly treated form. The protection of public health and the environment are the main concerns associated with uncontrolled wastewater irrigation. The use of saline and/or sodic drainage water and groundwater for agriculture is expected to increase. This warrants modifications in the existing soil, irrigation, and crop management practices used, in order to cope with the increases in salinity and sodicity that will occur.     

水源更换对自来水厂进水泵房给水泵的影响

以杭州市清泰水厂进水泵房给水泵为对象,通过对千岛湖作为第二供应水源后水质变化进行理论分析和试验研究,以及水源变化后水泵实际流量扬程等性能进行分析研究,提出在千岛湖、钱塘江等多水源下给水泵的选型设计。通过给水泵叶轮切削的方式,使给水泵新的工况点处于高效区域内,确保给水泵安全顺利生产运行,提高进水泵房给水泵的效率,满足日供水量的要求。     

Effect of soil water osmotic potential on growth and water relationships in barley during soil water depletion

Summary Barley plants (Hordeum distichum, L., cv. Zita) grown in a sandy soil in pots were adjusted during a pretreatment period of 5 days to three levels of soil water osmotic potential by percolating 61 of a nutrient solution with additional 0, 22.3 and 44.6 mM KCl. A drying cycle was then started and the plants were harvested when the soil water matric potential had decreased to –1.4 MPa, respectively 6, 7 and 8 days later.No significant differences in dry matter yields, transpiration coefficients and wilting percentages were found between treatments.During the drying cycle leaf water potential ( _l ) decreased concomitantly with decrease in soil water potential ( _s ) with almost constant and similar differences ( _l – _s ) for all treatments despite differences in levels of potentials. The concomitant decrease in leaf osmotic potential () was due partly to dehydration (58%) and partly to increase in leaf solute content (42%) independent of treatment. The part of total osmotic solutes due to K decreased relatively during the drying cycle.Close relationships were found between and _l as functions of relative water content (RWC). Identical curves for the two levels of salt treatment agree with similar concentrations of K, Cl, and ash found for salt treated plants indicating that maximum uptake of macro nutrients may have been reached.During the main part of the drying cycle the turgor potential as function of RWC was higher and decreased less steeply with decreasing RWC in the salt treated than in the non-salt treated plants.In the beginning of the drying cycle additions of KCI lowered the transpiration rates of the salt treated plants resulting in a slower desiccation of the soil and hence an increased growth period. A delay in uptake from a limited soil water supply may be advantageous during intermittent periods of drought.     

Production and water use in lettuces under variable water supply

The effects of a variable water supply on the water use, growth and yield of two crisphead and one romaine (i.e., Cos) lettuce cultivar were examined in a field experiment using a line source sprinkler system that produced a range of water regimes that occur in growers fields. Four locations at increasing distances from the main line were monitored through the season (i.e., from thinning to harvest, 28–63 days after planting (DAP)). These locations at the end of the season corresponded to: (1) rewatering to field capacity (FC); (2) watering with a volume 13% below that required in the field capacity treatment (0.87*FC); (3) 30% below FC (0.70*FC); and (4) 55% below FC (0.45*FC). A linear production function for dry matter accumulation and fresh weight vs. crop evapotranspiration (ET_c) was determined for lettuce during this period, giving a water use efficiency for dry matter of 1.86 g m^–2 mm^–1 and for fresh weight of 48 g m^–2 mm^–1 . For lettuce irrigated to field capacity, ET_c between thinning and harvest was 146 mm; maximum crop coefficients of 0.81–1.02 were obtained at maturity (55–63 DAP). For the three irrigation treatments receiving the largest water application, ET_c was higher in the Cos culivar than in the two crisphead lettuce cultivars which had similar ET_c. Plant fresh weight was more sensitive than dry weight to reduction in water supply. In the FC treatment, root length density and soil water extraction were greatest in the top 0–45 cm, and decreased rapidly below 45 cm depth. Soil water extraction by roots increased at lower depths when irrigation was reduced. Instantaneous rates of leaf photosynthesis and leaf water potential showed no response to the irrigation treatments in this study, despite differences in biomass production. Evaporation was determined to be the major component of ET_c for 45 of the 63 days of the growing season. The large loss of water by evaporation during mid-season and the apparent insensitivity of lettuce to the volume of irrigation during this period may provide an opportunity for reducing irrigation applications.