RESULTS AND DISCUSSION 



Changes in selected terrestrial parameters ttiat were induced by gravel 

 removal are identified in Table 28. These changes were based upon measured 

 levels of variation in each parameter at each site. In general, the degree 

 of both short-term and long-term changes in local faunal communities strong- 

 ly reflected the extent of disturbance to floodplain and riparian vegetative 

 commun i t i es. 



VEGETATIVE COMMUNITIES OF STUDY AREA FLOODPLAINS 



Vegetative communities of floodplain and riparian zones at the study 

 sites were typical of those occurring throughout arctic and subarctic 

 regions. In general, the Seward Peninsula rivers and the smaller North Slope 

 rivers usually were meandering or sinuous in configuration with well-defined 

 (incised) outside meander banks (Figure 61). This configuration and profile 

 created a relatively narrow floodplain (30 to 60 m) and al lowed extensive 

 development of mature shrub thickets adjacent to single channel rivers. 

 These shrub thickets usual ly were dominated by Sa I ix a I axensi s . On Inside 

 meanders (point bars) and in more active portions of floodplains (lateral 

 and mid-channel bars) herbaceous, woody pioneer and early willow communities 

 occurred adjacent to unvegetated gravels bordering the river. 



Meandering and sinuous rivers of the Northern and Southern Interior 

 were similar in pattern and were characterized by extensive shrub thickets 

 with dense stands of advanced and mature successional stage boreal forest 

 communities at the edges of active floodplains (Figure 62). White spruce 

 usually dominated these stands, but paper birch and balsam poplar also were 

 common. Similar pioneer and early shrub successional stage communities 

 occupied point bars and edges of lateral and mid-channel gravel bars. 



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