Although publicly financed incentive progranns may add several million acres to the 

 forest land base, an even larger area of existing forest land is expected to be con- 

 verted to other uses. The net loss is expected to be about 28 million acres by 2040, 

 mainly in the South and Pacific coast regions. Much of the loss in forest land is due to 

 conversions associated with roads and urban space utilized by a growing population. 



Productivity of Forest and Rangelands and Water for Increases in Renewable 

 Resources 



The productivity (output per acre or other measure of input) of forest and rangelands 

 varies widely as a result of differences in climate, soil, elevation, and latitude. The 

 biological potential exists to increase the output of all renewable resource products. 

 New technology or the wider use of existing technology from research is another 

 source of higher productivity. The economic efficiency of any investment depends on 

 the specifics of costs and revenues. Costs and revenues associated with investments 

 are not generally considered explicitly in this Assessment document, but they are 

 considered in the development of the 1995 RPA Program. 



Water quality and yields from forest and rangelands can be improved by various 

 management practices. Flooding, soil erosion, and the associated sedimentation of 

 streams can be restrained. 



Forest and rangelands in the United States provide forage and browse for over 70 

 million cattle, 8 million sheep, 55,000 wild horses and burros, 20 million deer, 400,000 

 elk, 600,000 antelope, and many other grazing animals. Vegetation management 

 practices can enhance the production of forage and browse for these animals while 

 protecting fragile soils and watersheds. For example, range forage productivity is 

 assumed to rise 0.7 percent per year on private lands. 



The 1 .7 billion acres of forest and rangelands and water have a large but unmeasured 

 capacity to supply opportunities for picnicking, camping, hiking, skiing, hunting and 

 fishing, wildlife observation, canoeing, swimming, and most other kinds of outdoor 

 recreation far in excess of current use. 



Forest and rangelands and water also have the potential to foster diversity and 

 increased numbers of most species of wildlife, including those of recreational and 

 commercial importance and endangered or threatened species. 



The known mineral resources on these lands are substantial. Thus, there exists the 

 physical potential to increase the productivity of nonrenewable resources. For these 

 outputs, productivity refers to the magnitude and efficiency of extraction. Technologi- 

 cal advancements that facilitate exploration, improve extraction, and enhance recov- 

 ery have made the energy and mining industries more productive in recent years. 



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