Ground water Termabsorption coefficient吸附系数A measure of the amount of radiant energy, incident normal to a planar surface, that is absorbed per unit distance or unit mass of a substance. accumulation (glacial)堆积All processes, which include snowfall, condensation, avalanching, snow transport by wind, and freezing of liquid water, that add snow or ice to a glacier, floating ice, or snow cover. The term also includes the amount of snow or other solid precipitation added to a glacier or snowfield by these processes. acid rain酸雨the acidic rainfall which results when rain combines with sulfur oxides emissions from combustion of fossil fuels.acidity profile酸度剖面The acid concentration in ice core layers as a function of depth as determined from electrical measurements. The magnitudes of some volcanic eruptions in the Northern Hemisphere have been estimated from the acidity of annual layers in ice cores taken in Greenland. This methodology is sometimes referred to as acidity signal or acidity record. adhesion内聚力the molecular attraction asserted between the surfaces of bodies in contact. Compare cohesionadsorption 吸附the adhesion of a substance to the surface of a solid or liquid. Adsorption is often used to extract pollutants by causing them to be attached to such adsorbents as activated carbon or silica gel. Hydrophobic, or water-repulsing adsorbents, are used to extract oil from waterways in oil spills.advance time irrigation行进时间 Time required for a given stream of irrigation water to move from the upper end of a field to the lower end of the field. advection水平对流The predominately horizontal large-scale movement of air that causes changes in temperature or other physical properties. In oceanography, advection is the horizontal or vertical flow of sea water as a current. aeration 曝气the mixing or turbulent exposure of water to air and oxgen to dissipate volatile contaminants and other pollutants into the air.aeration zone 包气带(also known as the unsaturated zone):The zone above the water table is known as the aeration zone. aerosol悬浮质Particulate material, other than water or ice, in the atmosphere ranging in size from approximately 10x-3 to larger than 10x2 磎 in radius. Aerosols are important in the atmosphere as nuclei for the condensation of water droplets and ice crystals, as participants in various chemical cycles, and as absorbers and scatterers of solar radiation, thereby influencing the radiation budget of the earth-atmosphere system, which in turn influences the climate on the surface of the Earth. aggressive water 侵蚀性水water which is soft and acidic and can corrode plumbing, piping, and appliances. agriculture water use water-use category农业用水 Composed of livestock, animal specialty, and irrigation water use. alkalinity 碱度the measurement of constituents in a water supply which determine alkaline conditions. The alkalinity of water is a measure of its capacity to neutralize acids. See pH. alluvium冲积物Sediments deposited by flowing rivers. Depending upon the location in the floodplain of the river, different-sized sediments are deposited.altithermal period 高温期A period of high temperature, particularly the one from 8000 to 4000 B.P. (before the present era), which was apparently warmer in summers, as compared with the present, and with the precipitation zones shifted poleward. Also called the hypsithermal period. anisotropy各向异性The condition under which one or more of the hydraulic properties of an aquifer vary according to the direction of flow.antecedent moisture前期降水量The soil moisture present before a particular precipitation event.aquaculture 水产业farming of organisms that live in water, such as fish, shellfish, and algae.aquaculture water use water-use category水产用水 Water used for farming of organisms that live in water, such as fish, excluding fish hatcheries (commercial water use), shrimp, and other shellfish. Activities included in SIC code 0273. Subset of animal specialties water use. aquatic 水生的growing in, living in, or frequenting water. aquiclude隔水层A unit of low permeability but is located so that it forms an upper or lower boundary to a groundwater flow system, now also called confining layer or leaky confining layer.aquifer 含水层a geologic formation that will yield water to a well in sufficient quantities to make the production of water from this formation feasible for beneficial use; permeable layers of underground rock or sand that hold or transmit groundwater below the water table. aquifer hydrology含水层 (1) A geologic formation, group of formations, or part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs (USGS); (2) A geologic formation, group of formations, or part of a formation having structures that permit appreciable water to move through them under ordinary field condition