In the present study, channel slope and stream origin did not correlate 

 with changes resulting from gravel mining. However, channel slope influences 

 the bed load carrying capacity of a stream — steeper slopes indicate 

 greater carrying capacity. This relationship is useful in evaluating po- 

 tential replenishment rates in a disturbed site after mining. Also, stream 

 origin has an influence because rivers of mountain and glacial origin charac- 

 teristically have larger quantities of gravel available than do rivers of 

 coastal plain or i g i n. 



All of the Gravel Removal Area Characteristics were found to signifi- 

 cantly influence the effects of gravel mining. The location of the material 

 site relative to the active channel is considered to be the most important 

 factor. Whether a material site is scraped or pit-excavated is important, 

 but often pits are located away from an active channel, avoiding the types 

 of changes that can be associated with scraping in active floodplains. 



The major effects of pit sites located in inactive floodplains and 

 terraces are the loss of vegetated habitat, the possibility for fish entrap- 

 ment, a change in the appearance of the floodplain, and long-term delay 

 in the re-establishment of pr ed i sturbance conditions. Where pit sites are 

 situated well away from active channels they have little effect on the 

 active channel and, there is little chance of contributing to channel diver- 

 sion. When situated close to active channels, particularly on the inside 

 bends in meandering systems, the possibility exists for diversion of the 

 channel through the pit, eventual ly forming a channel cutoff in the meander. 

 This problem highlights the importance of providing a buffer between the 

 material site and the active channel. Where pit sites are of suitable size, 

 of sufficient depth, and have contoured perimeters, they can increase local 

 habitat diversity and provide conditions suitable for fish and various 

 species of terrestrial fauna. 



Scraped material sites in active floodplains have minimal effects on 

 the floodplain environment when exposed gravel bars are only excavated above 

 the water level and slope and contours are maintained resembling those 

 of natural bars. Removal of vegetated areas or banks, which results in 



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