Rainbow trout 



turbidity, p. 47 

 Recirculated water 



cooling water, p. 191, J93 



pulp and paper industry, p. 198, 198 

 Recreation 



boating, p. 8 



BOR survey, p. 8 



Bureau of Outdoor Recreation, p. 7, 8 



fishing, p. 8 



ORRRC report, p. 7 



secondary contact recreation waters, p. 8, 9, 11 



surface waters, p. 3, 8, 9 



swimming, p. 7, 8 



water quality, p. 3, 8, 9, 11 

 Recreation waters see Primary contact recreation waters; 



Secondary contact recreation waters; Surface waters 

 Red River Basin 



dissolved solids, p. 168 

 Regulatory water 



return flow, p. 168 

 Residual sodium carbonate 



irrigation water, p. 170 



water quality, p. 170 

 Return flow 



irrigation water, p. 168 



regulatory water, p. 168 



subsurface drainage, p. 168, 169 



tailwater, p. 168 

 Rhinoviruses 



water pollution sources, p. 141 

 Rhizoclonium 



chemical composition, p. 55 

 Rio Grande 



dissolved solids, p. 168 

 River basin development 



plant nutrient and erosion control, p. 36 

 Rivers 



turbidity, p. 47 

 River systems 



irrigation, p. 168 



suspended load, p. 168 

 Ronnel 



toxicity, p. 37 

 Rooted aquatic plants 



navigational threat, p. 52 



nuisance growth, p. 52 



nutrients, p. 52 

 Root systems 



chloride concentration in soil solution, p. 156 

 Root zone 



humid climates, p. 172 



plant growth, p. 147 

 RSC see Residual sodium carbonate 



Saline soils 



evapotranspiration, p. 148 



plant growth, p. 148, 150 

 Saline water 



livestock tolerance, p. 133, 134 



supplemental irrigation, p. 174 

 Saline water fish see Fish; Marine and estuarine organ- 

 isms 

 Saline water tolerance 



cattle, p. 134 



hogs, p. 134 



horses, p. 134 



poultry, p. 134 



sheep, p. 134 



Salinity 



aquatic life, p. 35 



categories for habitats, p. 95 



direct and indirect efi'ects on wildlife, p. 94-95 



fluctuation effects, p. 95 



humid areas, p. 173 



irrigation water, p. 113, 115, 117, 145, 147, 148, 169 



irrigation water quality, p. 170 



Lower Colorado River, p. 96 



marine and estuarine organisms, p. 35, 67 



temperature, p. 96 



toxicity, p. 95 



toxic residues, p. 96 



turbidity, p. 96 



waterfowl, p. 94 



wildlife, p. 38 



wildlife management, p. 95 

 Salinity formulae 



supplemental irrigation, p. 173, 174 

 Salmon 



water temperature, p. 43 

 Salmonella 



irrigation water, p. 161 

 Salmonids 



dissolved oxygen, p. 44 

 Salt tolerance 



crop response, p. 148, 150 



crops, p. 148, 150 



field crops, p. 149, 150 



forages, p. 149, 150 



fruit crops, p. 150 



plant growth, p. 148, 150 



plants, p. 148, 148, 149, 150 



soil-water-plant relationships, p. 148 



vegetable crops, p. 149, 150 

 Sampling 



public water supplies, p. 19 



water management (applied), p. 177, 178, 179 

 San Joaquin Valley 



tile drainage, p. 170 

 SAR see Sodium adsorption ratio 

 Schistosomiasis 



irrigation water, p. 162 

 Scum 



nutrients, p. 51 

 Sea water 



anaerobic conditions, p. 77 



application factor, p. 81 



bioassay, p. 80 



color, p. 74 



floating materials, p. 76 



garbage dumps, p. 76 



heavy metals, p. 84 



microorganisms, p. 89 



oil pollution sampling, p. 73-74 



pesticides, p. 92 



phenols, p. 89 



plant nutrients and nuisance organisms, p. 77-80 



radioactive wastes, p. 49 



sediments, p. 76 



tainting substances, p. 77 



turbidity, p. 74 



waste water (pollution), p. 89 

 Secondary contact recreation waters 



fecal coliform level, p. 8, 9, 10 



fecal coliform monitoring criteria, p. 9, 10 



recreation, p. 8, 9, 11 



water quality, p. 8, 9, 10, 11 

 Sedimentation 



water treatment, p. 18 



228 



