Supralittoral (Zone) 



The portion of the shore immediately adjacent to the 

 tidal zone. 



Supraneuston 



Collectively, the minute organisms associated with the 

 upper surface of the film of water in lakes, streams, ^etc. e. g., 

 the water-strider. 



Supraorganism 



See Epiorganism. 



Surface Run-off 



See Run-off. 



Surface Soil 



The upper part of cultivated soil, usually stirred during 

 tillage operations, or the equivalent depth of 5 to 8 inches 

 in non-cultivated soils. 



Surplus Stock 



The portion of the population of game animals or fish 

 at the time of harvest that are in excess of the number needed 

 to maintain an adequate breeding stock. 



Survival Potential 



The capacity of an organism to survive in a given en- 

 vironment. 



Swale 



An arei of low, wet land; a low meadow. 



Swamp 



A land area containing excessive water much of the 

 year and covered with dense, native vegetation that includes 

 trees; but the term is used with various meanings, cf. Marsh, 

 Bog. 



Sward 



An area of grassland, especially one composed of sod- 

 grasses, cf. Turf. 



335 



