| 释义 |
ˌsub-irriˈgation
[sub- 2 a.]
The irrigation of land from beneath the surface, esp. by means of underground channels or pipes.
1880News & Press (Cimarron, New Mexico) 19 Aug. 1/6 Sub irrigation for wheat would be too expensive. 1904Bull. Bur. Census, U.S. Dept. Comm. & Labor No. 16. 25/1 In one of the systems of subirrigation the water is carried through pipes 14 inches below the surface. 1930Amer. Speech VI. 11 Subirrigation is accomplished by allowing water to stand in deep ditches from which it soaks laterally. 1979R. Adams et al. Dry Lands viii. 116/1 Sub-irrigation..is normally achieved either by creating an artificial water-table just below the ground surface or by burying a drip irrigation system or a network of perforated pipes.
Hence subˈirrigate v. trans. (also absol.), subˈirrigated ppl. a.
1903Sci. Amer. Suppl. 17 Jan. 22616/3 Where the subsoil transmits water freely, irrigation ditches may subirrigate large tracts of country without rendering them marshy. 1933Nat. Geogr. Mag. Feb. 189 (caption) The soil is remarkably fertile and is subirrigated by springs in the surrounding hills. 1950H. B. Roe Moisture Requirements in Agric. viii. 229 On Elgin Bench..the subirrigated district includes an area of about 60,000 acres. 1976D. Goldberg et al. Drip Irrigation i. 10 Drainage systems were utilized to function as a double action system, draining surplus water yet sub-irrigating through the same medium in a reverse operation. |