1、BRITISH STANDARD BS7562-1: 1992 Planning, design and installation of irrigation schemes Part1: Glossary of termsBS7562-1:1992 This British Standard, having been prepared under the directionof the Agricultural Machinery and Implements Standards Policy Committee, waspublished under the authorityof the
2、 Standards Boardand comes into effect on 1April 1992 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference AGE/30 Draft for comment 87/73202 DC ISBN 0 580 20554 1 Committees responsible for this British Standard The preparation of this British Standard was
3、 entrusted by the Agricultural Machinery and Implements Standards Policy Committee (AGE/-) to Technical Committee AGE/30, upon which the following bodies were represented: Agricultural Engineers Association British Agricultural and Garden Machinery Association Ltd. Health and Safety Executive Minist
4、ry of Agriculture, Fisheries and Food National Farmers Union Silsoe College Silsoe Research Institute UK Irrigation Association Water Services Association of England and Wales Well Drillers Association Amendments issued since publication Amd. No. Date CommentsBS7562-1:1992 BSI 07-1999 i Contents Pag
5、e Committees responsible Inside front cover Foreword ii 1 Scope 1 Section 1 Basic terms 1 Section 2 Site data and water resource terms 3 Section 3 Distribution terms 17 Section 4 Implementation terms 24 Index 26BS7562-1:1992 ii BSI 07-1999 Foreword This Part of BS7562 has been prepared under the dir
6、ection of the Agricultural Machinery and Implements Standards Policy Committee and is a glossary to a series of Parts containing recommendations on good practice in the planning, design and installation of irrigation schemes together with information and guidance. BS7562 is intended for the use of e
7、ngineers and farmers having some knowledge of the subject. It embodies the experience of engineers successfully engaged on the design and construction of irrigation schemes so that other reasonably qualified engineers may use it as a basis for the design of similar irrigation schemes. The other Part
8、s of BS7562 are written as codes of practice. A code of practice represents good practice at the time it is written and, inevitably, technical developments may render parts of it obsolescent in time. It is the responsibility of engineers concerned with the design and construction of schemes to remai
9、n conversant with developments in good practice, which have taken place since publication of the code. The six Parts of BS7562 are as follows. Part 1: Glossary of terms; Part 2: Code of practice for acquisition of site data 1) ; Part 3: Code of practice for irrigation water requirements 1) ; Part 4:
10、 Code of practice for water resources 1) ; Part 5: Code of practice for distribution systems and irrigation equipment 1) ; Part 6: Code of practice for implementation procedures 1) . A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards
11、 are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to27 and a back cover. This standard has been updated (see
12、 copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) In preparation.BS7562-1:1992 BSI 07-1999 1 1 Scope This Part of BS 7562 gives a glossary of terms used in the planning, design and installation of irrigation systems
13、. Units of measurement are generally quoted in SI units. No. Term Definition Section 1. Basic terms 1 01 actual crop evapotranspiration ETa (crop) Rate of evapotranspiration equal to, or smaller than, predicted ET crop as affected by the level of available soil water, salinity, field size, or other
14、causes; mm/day. 1 02 agriculturally effective rainfall Rainfall available for plant growth. 1 03 allowable soil water depletion Depth of water in the root zone readily available to the crop for given soil and climate, allowing unrestricted evapotranspiration as the fraction p of total available soil
15、 water between field capacity and wilting point; mm/m soil depth. 1 04 available water capacity (AWC) The soil water which is available or can be taken up by plants at any moisture content between field capacity and permanent wilting point; mm. NOTESandy soils contain less available water than clay
16、soils and loams form an intermediate group. 1 05 average annual rainfall For a specified place, the average annual value for rainfall is the mean of the annual amounts over the period for which rainfall statistics are available. In the UK the period seldom exceeds40 years; mm. 1 06 capping The forma
17、tion of a crust on a soil, often during a hot, dry spell, usually after heavy rain which causes the surface soil particles to break down, blocking up the soil pores. 1 07 crop coefficient/factor Ratio between crop evapotranspiration and the reference crop evapotranspiration (ETr); mm/day. 1 08 depth
18、 of irrigation, d Gross depth of water discharged by irrigation system (including application losses). 1 09 effective groundcover Percentage of ground covered by the crop when ET crop is approaching maximum, generally70% to80% of surface area. 1 10 effective rooting depth Soil depth from which the f
19、ull-grown crop extracts most of the water needed for evapotranspiration; mm. 1 11 field capacity The maximum possible amount of water held by a soil allowing for free drainage; mm/m. NOTEFor example, the field water content of soil2 days or3 days after heavy rain or irrigation. 1 12 infiltration rat
20、e The rate at which water is absorbed, or seeps into or through the interstices of a soil or other porous material; mm/h. a) initial infiltration rate. The rate at which the water enters the soil at the beginning of water application to the soil. b) instantaneous infiltration rate. The rate at which
21、 water enters the soil at a specific point in time. c) average infiltration rate. Rate of infiltration of water into the soil. The total depth of water applied divided by the time during which the water is applied.BS7562-1:1992 2 BSI 07-1999 No. Term Definition d) final infiltration rate. Rate at wh
22、ich water will enter the soil when, after initial wetting of the soil, the rate becomes essentially constant. 1 13 net irrigation requirement Depth of water required for meeting evapotranspiration minus contribution by precipitation, groundwater, stored soil water. This does not include operation lo
23、sses and leaching requirements; mm/period. 1 14 potential crop evapotranspiration ET(crop) Rate of evapotranspiration of a disease-free crop growing in a large field under optimal soil conditions, including water and fertilizer. Includes water loss through transpiration by vegetation and evaporation
24、 from the soil surface and wet leaves; mm. 1 15 readily available moisture The volume of moisture held in a soil that can be extracted without moisture stress. 1 16 reference crop evapotranspiration (ETr) Rate of evapotranspiration from an extended surface of8mm to15 mm tall, green grass cover of un
25、iform height, actively growing, completely shading the ground and not short of water; mm/day. 1 17 soil structure The arrangement of individual soil particles and aggregates. 1 18 soil water tension Force at which water is held by the soil or negative pressure or suction that has to be applied to br
26、ing the water in a porous cup into static equilibrium with the water in the soil. 1 19 wilting point a) permanent wilting point. The stage when a soil is so dry that plant roots are permanently unable to extract water at a rate sufficient to maintain turgidity. NOTEAt this stage, transpiration almos
27、t ceases, the plants wilt, and the plant is said to be at permanent wilting point. b) temporary wilting point. The stage when available soil water is reduced to the point where the rate at which the plant extracts available soil water is less than ET crop even though the soil moisture may be plentif
28、ul.BS7562-1:1992 BSI 07-1999 3 No. Term Definition Section 2. Site data and water resource terms 2 01 acid Having a pH value of less than7.0. 2 02 acidification The use of acid, usually hydrochloric, to increase the water supply from a borehole which is failing owing to encrustations on screens and
29、slotted pipes. It may also be used to improve the yield from bores in chalk or limestone by enlarging the fissures. 2 03 air-lift pump An appliance for lifting water in a well or sump. It consists of an air compressor at the surface and two pipes hanging vertically, with one pipe perhaps within the
30、other. The smaller pipe delivers compressed air to the depth at which water occurs. At this point a nozzle discharges the air into the free water and, by aerating it, causes its density to drop. This mixture of water and air is then forced upwards by the head of groundwater. 2 04 air-pumping Lifting
31、 water from a well using compressed air to aerate the water so that the air-water mixture will rise to the surface. 2 05 alkaline Having a pH value above7.0. 2 06 alluviation (or aggradation) The deposition or building-up of sediments by stream or water action, particularly along rivers and estuarie
32、s where flow is retarded. 2 07 angle of repose The maximum slope, measured from the horizontal, at which rocks, soils, and loose material on the banks of canals, rivers, dams, or embankments remain stable. 2 08 angle of slide The angle (measured in degrees from the horizontal) of the sloping sides o
33、f a canal, reservoir, or other cutting, at which a landslide will start. The angle varies considerably and the water content has a major influence. 2 09 annular space The space or cavity between the outside of the borehole casing and the surrounding ground. 2 10 apron A hard floor or surface to the
34、bed or banks of a river or canal, or below chutes, spillways, groynes or the toes of dams, to minimize scour. It may consist of begwark, mattress, timber, mass concrete, riprap, or preferably reinforced concrete. 2 11 aquifer A relatively permeable or fissured deposit which yields useful supplies of
35、 water when tapped by a well. 2 12 area of influence (well) The surface area around a well or borehole with the same horizontal extent as that part of the underlying water-table that is lowered by pumping from the well at a given rate of discharge. 2 13 artesian aquifer A confined aquifer in which t
36、he water is under sufficient pressure to cause water to rise above ground level. 2 14 artesian borehole A borehole which penetrates an artesian aquifer and in which the water level rises above ground level.BS7562-1:1992 4 BSI 07-1999 No. Term Definition 2 15 artificial recharge Augmenting the natura
37、l infiltration of surface water or rainfall into underground rocks or channels. The recharge may be by spreading of water, by changing the natural conditions, by some form of construction or by putting down wells. 2 16 artificial recharge of aquifer (orgroundwater increment orgroundwater recharge) T
38、he introduction of surface water, such as streams and rainfall, into underground storage. 2 17 backblowing A method of improving the water yield from boreholes, particularly in fissured rocks. It is not unlike swabbing in action and is sometimes more effective. It employs compressed air (a) for pump
39、ing in the bore by air lift, or (b) by pumping in air (when the top of the hole is sealed) until the maximum pressure is obtained and then releasing it suddenly. 2 18 backwash The back flow of water which follows the breaking of a wave; it scours and carries the finer material towards deeper water w
40、here it is temporarily deposited. 2 19 baffles A series of plates, vanes or guides set in a channel or conduit to secure more uniform flow conditions by damping eddies. 2 20 bailer A tool used in drilling for removing sludge, mud or sand from a borehole. It consists of a steel tube with an open end,
41、 the other being either closed or fitted with a simple valve. 2 21 balanced earthworks Earthworks in which the “cuts” equal the “fills”. The ideal is not easily achieved but is a target when planning the layout of trenches, water supply channels, and other hydraulic works. 2 22 base flow The sustain
42、ed flow of streams from snow and glaciers (not normal in the UK) or from underground storage and not related to direct runoff. NOTESustained flow resulting from drainage of large lakes or springs or other outflow of groundwater, as opposed to surface runoff. 2 23 battering The artificial sloping ban
43、k of a river or other bank to a flatter grade to reduce caving or collapse of the earth. The procedure is often allowed by beaching with stone or by grassing or other vegetation to bind the soil layers. 2 24 beaching A layer of stones for revetting below the level of stone pitching a reservoir or em
44、bankment: the layer is from0.3m to0.6m thick and stone size from75mm to200mm. Also applied to a layer of stones of about150mm diameter to prevent scour due to wave action. 2 25 bed load The weight or volume of boulders, pebbles, and gravel rolled or moved by a stream along its bed in unit time. 2 26
45、 bed scour The wearing away of the rock, soil, or deposited material from the bed of a river by flowing water or waves. 2 27 bed slope The inclination of the bed of a stream along its course given as difference in elevation per unit of horizontal distance.BS7562-1:1992 BSI 07-1999 5 No. Term Definit
46、ion 2 28 bentonite A very fine clay substance with a maximum particle size of2m; has a very high swelling property when moistened. Used in reservoirs, ponds, irrigation and water supply channels, and in small farm dams to reduce seepage. 2 29 blow out A failure due to tunnelling or piping in earth d
47、ams or channels. 2 30 boil The seepage or inflow of water and fine sand or silt at the bottom of an excavation due to a high external water pressure. 2 31 bonded gravel screen A well screen of an improved type and made from particles of gravel bonded together with a resin adhesive. 2 32 borehole A h
48、ole drilled into the ground, from the surface or from subsurface excavations, to secure geological information or for the drainage or abstraction of water. 2 33 borehole casing A plain or perforated pipe of steel or other material inserted in a borehole; often used in weak or loose ground. 2 34 bore
49、hole log A record, mainly of the rocks penetrated during the drilling of a borehole, and prepared by the master driller or field geologist. 2 35 borehole pattern The disposition or spacings of a group of boreholes put down for water supplies or for geological information. 2 36 borehole pump In general, a centrifugal pump, often electrically driven and designed to operate in a borehole. 2 37 borehole samples Refers to the soil or rock chippings, sludge, or core extracted during drilling and used to ascertain the nature of the ground penetrated in the boreho
