is a better understanding of how water 

 yield is influenced by manipulating 

 vegetation growing under different soil 

 and climatic conditions. Also needed 

 are practical methods for the land 

 manager to achieve satisfactory water 

 yields. 



2. Snow management to control snow 

 accumulation and snowmelt. More 

 knowledge is needed on synthesizing 

 meteorology data with vegetative man- 

 agement and the design of engineering 

 structures to influence snow deposition, 

 snowpack stability, and rate of snow- 

 melt. Better methods for reducing sub- 

 limation and evaporation losses are 

 needed. 



3. Flood control-abatement through use 

 of construction works and vegetation 

 management and protection of flood- 

 prone areas from economic loss. Ex- 

 panded research is needed in many 

 areas to develop management practices 

 for the riparian zone to sustain and 

 protect water resources, esthetics, wild- 

 life habitat, and recreation values. 



4. Reduction of nonpoint source pollution 

 to enhance water quality. Many areas 

 need study, including erosion and sedi- 

 mentation control, identification of 

 basic contributors to nonpoint source 

 pollution, nutrient cycUng processes, 

 atmospheric deposition, land manage- 

 ment alternatives, insect and disease, 

 fire, and the use of fertilizers and pesti- 

 cides. Although research has been con- 

 cerned with alleviation of pollution 

 resulting from forestry practices — 

 including prescribed fire, road construc- 

 tion, pesticide use, and mining on for- 

 ests and rangelands, additional studies 

 in these areas are needed. New research 

 should focus on: (a) The nature, extent, 

 and effects of pollutants resulting from 

 intensive timber culture; (b) develop- 

 ment of standardization procedures for 

 predicting pollutants resulting from 

 various land use practices; and (c) es- 

 tablishment of guidelines and practices 

 to minimize water pollution from for- 

 estry activities. 



5. Reclamation of disturbed lands. Intensi- 

 fied research is needed on developing 

 methods to minimize watershed dam- 

 age during exploratory testing, surface 



mining activities, and other land-dis- 

 turbing operations. Advanced methods 

 in land forming and rapid revegetation 

 under a wide range of climatic, topo- 

 graphic, geologic, and soil conditions 

 are needed. Objectives should include 

 protecting the quality and quantity of 

 existing surface and ground water sup- 

 plies, conserving water during land- 

 disturbing and rehabilitation opera- 

 tions, and increasing available supplies 

 where feasible. 



6. Treatment and disposal of wastes on 

 land. Land areas are increasingly sought 

 for treatment and disposal of effluents, 

 sludges, and other wastes. More re- 

 search is needed on techniques for land 

 disposal of various wastes while main- 

 taining watershed values, including pro- 

 tection of water quality and possible 

 enhancement of water availability by 

 effluent irrigation. 



7. Taiga hydrology in Alaska. Additional 

 research is needed to develop land man- 

 agement practices for protection of 

 water resources in central Alaska. Data 

 developed would be applicable to about 

 100 million acres. 



8. Acid precipitation — causes, effects, 

 and control. Little attention has been 

 given to this problem. Preliminary re- 

 search shows a continual degradation 

 in precipitation quality in much of the 

 United States. Concern has been raised 

 about possible adverse effects on forest 

 and aquatic ecosystems. Acid precipita- 

 tion is most evident in the Northeast, 

 but is spreading to other parts of the 

 Nation. 



9. Insect and disease protection. Tech- 

 niques need to be developed to evaluate 

 how damage caused by insects, diseases, 

 and air pollutants relates to the quality 

 and quantity of water produced. Re- 

 search is also needed to develop pest 

 management systems consisting of var- 

 ious techniques and strategies to regu- 

 late impacts of insects and diseases on 

 water quality and land uses and values. 

 For example, improved survival and 

 growth of many woody plants on harsh 

 disturbed areas can result from intro- 

 duction of mycorrhizal fungi. Also to 

 be learned is the influence of various 

 pollutants on air quality and the sec- 



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