《节水灌溉技术》形成性考核册作业答案

《节水灌溉技术》形成性考核册作业答案"Water saving irrigation technology" formative examination book operation answers1: according to the amount of rainfall, China is divided into five zones of precipitation:(1) rain belt: annual rainfall of more than 1600mm, rich rice, tropical and subtropical crops, is the main producing areas of China in double cropping rice. (2) humid zone: annual rainfall over 800~1600mm, is the main rice producing areas in China, as well as winter wheat, rape and other crops. (3) semi humid zone: the annual rainfall is 400~800mm, which is the main wheat, cotton and other dry crop areas in china. (4) semi-arid zone: annual rainfall of 200~400mm, mainly in pastoral areas. (5) arid zones: annual rainfall of less than 200mm, almost no agriculture.2, agricultural water-saving technology includingwater-saving and drought resistant crop varieties, covering technology, water-saving cultivation technology, adjustment of crop planting structure, soil moisture, water retaining agent application.3 、 current situation and development trend of water-saving irrigation technology in china:(1): the development of canal seepage control technology has good performance, low price, easy construction materials, the development of a number of construction machinery; there is lining in high cost, some technical problems need to improve,construction machinery performance, type less; (2) low pressure pipeline technology, made certain achievements in technology and developed a number of suitable materials, equipment and construction technology; problems are mainly materials, equipment and technology needs further improvement and research; (3): sprinkler irrigation technology has a certain scale, developed a variety of sprinkler irrigation equipment and complete production; problems are sprinkler irrigation materials, equipment quality and performance type of distance, there is a large gap between the advanced level, durable, technology and management level is relatively low; (4) improving surface irrigation technology: Based on our reality Using many improved methods, achievements; problems is the lack of technology, equipment, field method can be popularized in large area of land; (5): rice water-saving irrigation has been successfully achieved "large area thin shallow wet dry" irrigation control, the problem is to study the comprehensive application of single technology the.4, China's channel anti-seepage methods are mainly:(1) soil lining: the characteristics of local materials, low cost, simple construction, but the frost resistance and poor durability; (2) soil cement seepage prevention: can use local materials, low cost, easy construction, but the frost resistance of the poor; (3) stone waterproof: frost resistance and anti impact performance is good, construction simple, strong durability, but impervious ability is difficult to guarantee, labor; (4) membrane: good anti-seepage effect, light weight, convenient transportation, low cost, convenient construction; (5): concrete anti-seepage effect, impactresistance, good durability, but the construction is complicated, cost high; (6): the advantages and disadvantages of asphalt concrete and asphalt concrete are similar, but the former is lacking.5, anti frost design should be carried out according to local conditions, safe and reliable, economic and reasonable principle, and according to the following requirements: (1) collecting relevant information, and according to the soil, groundwater depth and channel to the basic principle of the same divided canal; (2) by calculation or experiment, determine the design section of representative points deep freeze and frost heave, frost heave classification of foundation soil; (3) selection section, anti-seepage materials and structures suitable;(4) checking the frost displacement of each part of the channel, and determining the necessary measures to prevent frost heaving.6, the advantages of low pressure pipeline water delivery: improve the effective utilization of water, energy saving, land and land, low cost, timely irrigation, increase production and income.The current situation of the development of China has a rapid development in the North China well irrigation district, has achieved remarkable economic and social benefits, has a certain development in the northwest and southern regions.7. The composition of the low pressure pipeline network: watersource, pump, pipeline system, water supply unit and protection equipment. The pipe network system can be divided into four types: Mobile, fixed, semi solid and pipe and canal.8. Steps and methods for determining pipe diameter at all levels of the network:(1) to determine a reasonable irrigation system; (2) the design flow calculation at all levels according to the pipeline control irrigation area, crop types and water requirement (in accordance with the water peak or key irrigation period of crop and one of the biggest irrigation amount calculated); (3) through the technical and economic analysis to determine the levels of diameter.The fourth chapter to the fifth chapter1. Reasonable ground irrigation techniques must meet the following requirements:To ensure the water quota by the development of irrigation irrigation to the fields, the soil moist all irrigation area on a uniform layer of soil, plan to have enough water, and according to the ventilation and temperature to regulate soil; ensure the irrigation water has the highest utilization rate, to prevent the surface of running water, irrigation, drainage, waste on the loss the phenomenon, and as far as possible to avoid deep leakage; do not destroy the soil aggregate structure or make it to the lowest extent, soil loose state makes irrigation, to reduce ground evaporation; selected irrigation technology to adapt to the new agricultural techniques, and the closecombination of agricultural technical measures, also should adapt to the agricultural mechanization; have higher labor productivity, and is likely to gradually make irrigation mechanization and automation; it is simple, economic, low investment cost, easy to popularize.2, the irrigated land leveling should meet the requirements, convenient irrigation farming, contiguous operation and tractor should meet the requirements: meet the requirements of irrigation; smooth accuracy; maintain a certain minimum earthwork workload; fertility; no reverse slope exists.3 the advantages of membrane irrigation include saving irrigation water, reducing soil evaporation and increasing crop yield.4, the main technical requirements of membrane irrigation:Land is the basic condition to ensure the uniformity of film hole irrigation and water before sowing; spraying herbicide, prevent the growth of weeds; needs of paving, ridging; prevent leakage and waste water discharge deep tail, prevent on irrigation and flood irrigation; to have a certain slope.5 the advantages of sprinkler irrigation technology include saving water, increasing production, saving labor, reducing land cover, maintaining soil and water conservation, and strong adaptability.6 the main technical requirements and physical concepts of sprinkler irrigation system:Sprinkler strength: unit time of sprinkler irrigated land in the water depth, divided into the average sprinkler sprinkler intensity, intensity; intensity of dripping water from water droplet: unit area, water droplets on the soil or crop kinetic. With the water droplet diameter as characteristic value, the average water hammer intensity should be 1~3mm, and the uniformity of sprinkler irrigation is the uniformity of water distribution in sprinkler irrigation area. Expressed by spraying uniformity coefficient.7 the composition and function of pipeline sprinkler irrigation system:The five part: water source: the water needed for irrigation;Water pump: pressurizing and lifting water;Power machine: provide the power needed; pipe system: the introduction of water into the irrigated fields;Sprinkler: provide adequate water, range, etc.8 piping irrigation network layout should pay attention to:The pipes should at least the total amount (Guan Chang, minimum diameter) within the pipe network; uniform pressure; meet the needs of the water unit; strive to smooth, reduce turning, turning point, inverse slope; reduce the impact on the tractor; mobile and semi fixed type should be set up two sets of pipes used in rotation, so as not to damage the mobile crop; set theappropriate control equipment; pipe rolling high exhaust device.The sixth chapter to the eighth chapter1, micro irrigation advantages: water saving, energy saving, adapt to all kinds of terrain and soil; improve crop yield; easy to control automatically.2, there are five types of micro irrigation:Drip irrigation: irrigation water is dripping, frequently, evenly and slowly, into the soil of the main root zone of the crop;Micro sprinkler irrigation: the water is sprayed with small raindrops, which can increase air humidity and improve microclimate in the field;Infiltration irrigation: the irrigation pipe is a water seepage pipe with no obvious water outlet. It can meet the demand of crop water timely and appropriately by infiltrating the soil. The evaporation of surface soil is small and water saving, but the construction is inconvenient and inconvenient to manage;Tubular flow irrigation: the characteristics of anti blocking performance, the high efficiency and convenient management;Pulse type micro irrigation: characterized by good anti clogging performance and water landscape effect, uniform flow and strong adaptability.3, the composition and function of micro irrigation system:The four part: water source: water quality requirements can be used as micro irrigation water source;First hub: it is responsible for the pressure, water treatment, detection and control tasks of the whole system, and is the control and dispatching center of the whole system;Transmission and distribution network: it is responsible for water conveyance and water distribution;Emitter: the distribution of pressure and water in the pipeline evenly and stably into the field.4 emitter mainly has five kinds: emitter, micro nozzle, small pipe outlet, emitter combination, pulse micro sprinkler combination and seepage pipe.5, micro irrigation system operation and management of the main content:Water management;Engineering operation management: including pipeline, filter, fertilizer equipment and so on;Equipment maintenance and repair: including pipeline system, irrigation, filter, fertilizer equipment maintenance;Economic and organizational management: including optimizing varieties, improving the efficiency of farmers, making farmers pay more attention to micro irrigation technology; allowing farmers to participate in micro irrigation system management; setting up professional management organizations; strengthening the training of managers.6. The water requirement of drought crops is mainly affected by meteorological conditions, crop types and varieties characteristics, soil properties, agricultural cultivation and management measures of different growth stages of crops.The regulation of crop water requirements: the general situation is arid and semi arid area of crop water requirement than in humid areas, drought year than in wetter years; crop growth period longer than the short ones; extensive cultivation, low management level, the management level of higher than the intensive and meticulous farming; early growth of water demand, the growth of Sheng during the period of high water demand.7. Non sufficient irrigation means the part of crop growth period to meet the crop water requirements, or intentionally to give the crop less water.Practical experience in our country: the method of reducing irrigation times for drought crops is to reduce irrigation which has little influence on crop growth and yield,To ensure that the key period of irrigation are also methods to reduce the irrigation quota; and will cut down the water to expand irrigated area or will save water under irrigation tohigh economic value crops, obtained the highest total output or output.8 soil moisture is the percentage of soil moisture in the soil.A determination method of drying method, alcohol burning method and infrared method, tensiometer method.Soil field capacity is the maximum amount of water that a field can retain under natural conditions. The determination method of the representative field irrigation 48 hours (in each layer of moisture difference within 1%) the average field water holding rate.9 mode and characteristics of rice water-saving irrigation:"Shallow, wet, sun" mode:。