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o� a� <br /> Thomas A. Colbert Page 2 <br /> plant communities as a guide for selecting species which will be suitable for <br /> conditions at a particular site. <br /> Great advances have been made in reclamation technology in the past twenty years. <br /> Probably the most significant of these has been the"domestication"of many <br /> species--especially native species—for revegetation and the development of <br /> commercially available sources of seed and nursery stock. With the emphasis on <br /> diversity as a desirable(and in many instances a required)trait of reclaimed <br /> landscapes,it is not uncommon to see seed mixes containing twenty or more <br /> species. Such mixes would not have been feasible in the west more than ten years <br /> ago. <br /> 'The alpine zone refers to the high elevation zone occurring above the treeline. <br /> Despite the progress that has been made in reclamation technology,reclaiming <br /> alpine disturbances remains problematic. Revegetation of high elevation <br /> disturbances remains problematic. Problems are exacerbated by harsh climatic <br /> conditions,marginal or unsuitable soils,and a short or non-existent supply of seed <br /> of adapted plant species. Results in Colorado,Alaska and elsewhere have shown a <br /> tendency for species adapted to lower elevations to decline in vigor following initial <br /> establishment when seeded in alpine environments. Good initial stands may <br /> eventually die out altogether. Especially on non-topsoiled areas,use of inorganic <br /> fertilizers can temporarily support improved agronomic species such as smooth <br /> brome and timothy,but when fertilization is curtailed,without the ability to cycle <br /> nutrients in the soil,stands may be lost. Plant litter may remain undecomposed in <br /> the soil for years because of low soil microbial activity. <br /> Acid Forming Materials <br /> A complicating factor to contend with for reclaiming mining disturbances at high <br /> elevations is the frequent occurrence of acid forming materials. Such materials may <br /> include overburden,waste rock,below-grade ore,or tailing. A material is defined <br /> as acid-forming of the neutralization potential(as carbonate)is less than the acid <br /> potential(as sulfate). The basic geochemical mechanism is the same for all acid <br /> forming materials regardless of rock type---the oxidation of pyrite or other sulfides <br /> which can be generalized by the following equation— <br /> (Fe,Pb)S2+H2O+3.5 02-+ (Fe,Pb)SO4+H2SO4 <br />