外文翻译--节水灌溉

外文翻译一节水灌溉河北农业大学本科毕业（设计）论文外文文献翻译学院：城乡建设学院_____________ 专业班级：农业水利工程0901班学号： _________ 2009224010113 ___________ 学生姓名： ____________ 周飞 ________________ 指导教师姓名:指导教师职称：讲师_________________二零一三年三月Water-savins irrigation1.Existing water-saving irrigation methodsIrrigation methods, field water distribution method is how to have been sent to the farms, the irrigation water is evenly distributed to the active layer of the crop root. Irrigation water is the means by which to enter the active layer of roots, irrigation methods can be divided into surface irrigation, sprinkler irrigation, micro-irrigation and underground irrigation.U surface irrigationSurface irrigation is an ancient traditional irrigation method, in general, it is as compare whether water-saving basis points. Surface irrigation technology are constantly develop and constantly improve, so there are many more water-efficient than traditional surface irrigation technology.1.1.1new furrow irrigation toolsTraditional furrow irrigation with artiflcial opening from the distribution channel water into the furrow, it is neither accurate and inconvenient^ and often cause the field of water loss due to water port leakage countries have already adopted the siphon (for open channel water ) or gate hole pipe (aqueduct) drainage, China has done a number of tests, proven to improve field water utilization rate of 5% to 10%.1.1.2surge irrigationModern foreign developed wave Chung (groove) border irrigation or intermittent ditch (furrow) irrigation, traffic control into the ditch (furrow) is intermittent water and then put a period of time (a few minutes or tens of minutes) to field stop the water for some time (a few minutes or tens of minutes), and so forth, so that you can make along the ditch (furrow) the length direction of the water distribution is more uniform. Fields of water utilization up to 80% to 90%.Film hole irrigation (also known as the film hole irrigation)Gully, made on the film of water flow in the membrane, crops grow hole to penetrate the land, so that irrigation efficiency is high, generally water-saving 25% to 35%, an increase of 15% to 20%, they do not specifically facilities.1.2IrrigationSprinkler to spray through the air, due to the pressure of the commonly used pressure aqueduct In general, Its obvious advantages irrigation uniformity^ less of farmland, save manpower, strong adaptability to the terrain. The main disadvantage is influenced by wind, high investment in equipment. More in our country are the following: fixed pipe sprinkler, the semi-mobile pipeline sprinkler irrigation, a rolling shift sprinkler manifold, when the needle irrigation machine, a large pan spray irrigation machine, grain irrigation machine in inicroirrigators units and so on.1.3drip irrigationIrrigation water with a small plastic tube directly sent to the the Meike crop roots near thewater drip out slowly by drippers, a sophisticated irrigation methods, only need water to irrigationcan truly only irrigation crop Instead of filling the land. And can be a long time in the crop rootzone moisture in the optimal state, so to save water and Increase production. But its biggestdrawback is the Dripper out flow orifice is small, the flow rate is low, so serious congestionproblems. Irrigation water must be carefully filtering and processing. At present, China has onlynoticed to prevent physical clogging equally serious clogging the biological and chemical cloggingproblem has not been taken seriously enough. The main way of drip irrigation: fixed-ground dripirrigation, semi-fixed-ground drip irrigation- Membrane under irrigation, drip irrigation and otherunderground• L4micro-sprinkler irrigationSome places called mist irrigation, and drip irrigation similar too easy just to overcome the Dripperdisadvantage of clogging the drippers to micro sprinklers^ micro-sprinkler flow orifice large, largenumber of traffic flow rate faster Unlike drippers so easy to plug, but the traffic has increased,capillary accordingly should bold some 1 to 2 micro sprinklers installed in every crop or treeusually can meet the needs of irrigation. Micro nozzle still clogged filtration problems, andtherefore should be given adequate attention, the cost per hectare is similar to fixed-dripirrigation. Gradually replaced by drip irrigation micro sprinkler irrigation in a foreign country.Especially suitable for irrigated orchards.1.5 subsurface irrigationSimilar to the subsurface irrigation and underground drip Just the Dripper all buried in theunderground seepage head instead, the seepage head of water Unlike drippers as drop by drop outflow,but slowly seepage, such seepage head is not easy soil particles and root blockage. Recentlyintroduced in a foreign countn r using waste tires processed into porous percolation pipe, and thepilot of a small area, but the clogging of the micropores seepage pipe is a serious problem, withoutthe test to test for a long time should not be hastily promotion.L6un(lerground irrigationThe underground irrigation irrigation is a method to control the water table. To irrigationgroundwater table elevation to the water can enter the height of the root activity layers, the groundremains dry, so very provincial water, no irrigation, groundwater levels drop down. The limitationsof this approach, only the root activity layers impermeable layer Caixing.2.Select the factors that affect water-saving irrigation methods 2.1 weather conditionsChina from the southeast coast to the inland northwest, generally divided into sub-huinid areas,semi-humid areas, semi-arid and arid regions, With dn ness incremental, the dependence of cropirrigation is incremented accordingly. Humid regions for many years the average annual rainfall isgreater than the cultivation of dry crops in the field water consumption, water resources total morethan just a lack of precipitation in the dry season and drought years, supplemental irrigation isrequired; semi-humid areas average annual rainfall is basically in line with planting drought cropwater demand, but due to the uneven 2 distribution of precipitation, dry years and dry season watershortages more; semi-arid areas average annual rainfall can not meet the crop water requirements, ifthere is no irrigation, agricultural production is very unstable, such areas such as irrigation,wasteland farming, the destruction of natural vegetation, can easily cause desertification; rainfallis scarce in arid regions, irrigation agriculture, water scarcity of such areas, river runoff from the alpine rain and snow melt water, Industry and agriculture not only depend on the development and survival of the natural vegetation along the river channel near river water for irrigation, and therefore reference, must take into account the natural ecological water.2.2the topography and hydrogeological conditionsTopography and hydrogeological conditions affecting the natural distribution of rainwater, will also affect the pattern of water-saving Irrigation. Ground on steep mountain hilly area prone to soil erosion and drought, water-saving irrigation to adopt comprehensive measures. Cultivation technology and terracings field ridges through agricultural consumption, reduce the sloping soil erosion andsoil evaporation; gullies on the construction of embankments, or in suitable locations for the construction of water cellars, storing runoff solve drinking water and a small area irrigation water; repair reservoirs in the gullies and tributaries, centralized control runoff diversion project isolated tangba communicatioib formation of tf Chodo Jiegua-irrigation systems, improve rain water utilization and irrigation water to ensure rate.2.3the use of surface water resources conditionsPlain areas and open mountain basin, water conditions were better, but different parts have significant differences. Piedmont sloping plain terrain slope, coarse sediment, runoff smooth, rich groundwater recharge, water quality, is conducive to the development and utilization. Slowing the central plains terrain slope sediments thinning increased level surface several times due to river flood diversion, post depression to staggered, affect runoff excretion increased groundwater salinity under arid climatic conditions, soil there will be varying degrees of salinization phenomenon. The plains lower part of the lakeside and coastal area, low and flat, the soil is heavy clay, surface and underground runoff, poor drainage, arid climatic conditions, high salinity of groundwater development and utilization of difficulties, serious soil salinization. This region in the river downstream, dry season, the rivers and the rainy season is threatened by the flood, so building large and medium-sized irrigation and well irrigation area in the plains area, due to the different parts of which the landforms, water conditions and accompanying drought waterlogging, salinity and other disasters also vary from place to place.2.4specific plantingFruit trees, irrigation quota vary according to the type of fruit trees, varieties and rootstock characteristics, age size. Drought-tolerant tree species, such as jujube, chestnut and rootstock species with lower water requirements the irrigation quota can be as small; poor drought tolerance of species, such as grapes, apples, pears, irrigation quota should be3larger. The saplings should be less irrigation, the results of fruit trees can be more than irrigation. Saudi orchards should small water more than irrigation. Saline land orchard irrigation should be noted that the groundwater level, in order to prevent the return of salt, returned to base. Generally into one of the most suitable age fruit trees irrigation, soil moisture completely wet fruit tree roots within appropriate. Under the conditions of use of water-saving irrigation methods, irrigation to reach a depth of 04-0.5 meters, plenty of water up to 0.8-1.0 meters.To mature vine irrigation, mainly in the grape growing infancy, before and after flowering, berry enlargement period and grapes after harvest period, the general irrigation 5-7 times.节水灌溉一.现有的节水灌溉方法灌水方法即田间配水方法，就是如何将己送到田头的灌溉水均匀地分布到作物根系活动层中去。