size, vegetation type, cleanup method, extent of plant removal, site 

 use, etc.) to warrant further consideration. 



Cleanup of residual oil or oil quantities too small to be effi- 

 ciently removed with conventional collection techniques is accom- 

 plished by burning the contaminated site. Producers, and consumers 

 which do not abandon the site, are lost. Fire accelerates biomass 

 decomposition, thereby increasing the availability of soil nutrients 

 which enhances plant reestablishment. 



Excavation and removal of soils impregnated with oil, brine, or 

 other deleterious substances alters soil structure and soil nutrient 

 reserves. Loss of available nutrients impoverishes the site, 

 slowing down later plant recovery. The consequence of soil struc- 

 ture alterations is more important as this physical feature regulates 

 several important aspects of later plant establishment and growth. 

 Chief regulatory factors are soil moisture and soil air. Replacement 

 soil, if similar in type, profile level, and texture, facilitates 

 rapid reestablishment of previous soil conditions. Dissimilar 

 substrates (in salinity, texture, structure, fertility) alter micro- 

 environmental conditions such that subsequent plant assemblages 

 different from the original flora may result. The significance of 

 such abiotic alterations upon biotic components is a function of the 

 alteration's areal extent, existing site conditions (whether natural 

 or impacted), and future site uses. 



3.1 Woodlands 



Removal of woodlands as a result of oil spills causes long-term 

 (50 to 70 yr) changes in community structure and biomass. 

 Replacement occurs with grasslands and possibly a brush-grass 

 complex in later stages. An important source of food is 

 removed for the following consumer groups: hoofed mann^als, 

 small mammals, certain granivorous birds, and soi^ie invertebrate 

 consumers. Magnitude of importance is dependent upon amount 

 removed or altered. Cover or shelter requirenents are altered 

 or removed for long periods for predatory riaininals, raptors, and 

 certain insectivorous songbirds, as well. 



3.2 Grasslands 



Removal of grasslands can result in long-term changes, but with 

 restoration and favorable growing conditions, recovery gener- 

 ally occurs within two yr. Usually only a temporary loss of 

 food and cover results to consumer groups as few species are 

 specifically linked to specific grass species; life form is 

 more critical. 



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