| Abstract from DBPedia | Irrigation is the agricultural process of applying controlled amounts of water to land to assist in the production of crops, as well as to grow landscape plants and lawns, where it may be known as watering. Agriculture that does not use irrigation but instead relies only on direct rainfall is referred to as rain-fed. Irrigation has been a central feature of agriculture for over 5,000 years and has been developed independently by many cultures across the globe. Irrigation helps to grow agricultural crops, maintain landscapes, and revegetate disturbed soils in dry areas and during periods of less than average rainfall. Irrigation also has other uses in crop production, including frost protection, suppressing weed growth in grain fields and preventing soil consolidation. Irrigation systems are also used for cooling livestock, dust suppression, disposal of sewage, and in mining. Irrigation is often studied together with drainage, which is the removal of surface and sub-surface water from a given location. There are various types of irrigation. Micro-irrigation uses less pressure and water flow than overhead irrigation. Drip irrigation trickles out at the root zone.灌漑（潅漑、潅溉、かんがい、英: irrigation）とは、農地に外部から人工的に水を供給すること。農作物の増産、景観の維持、乾燥地帯や乾期の土壌で緑化する際などに利用される。他にも農業生産において、作物を霜害から守る、穀物の畑で雑草を抑制する、土壌の圧密を防ぐといった用途もある。対照的に直接的な降雨のみで行う農業を乾燥農業と呼ぶ。灌漑システムは、塵の飛散防止、下水処理、鉱業などにも使われる。灌漑と排水は組み合わせて研究されることが多い。 なお、「灌」「漑」は二文字とも常用漢字の表外字のため、報道では新聞常用漢字表により「かんがい」とひらがなで表示されるのが一般的である。学校の教材等も同様である。 (Source: http://dbpedia.org/resource/Irrigation) |
