Ch. 5— Maintaining Biological Diversity Onsite • 121 



and the high cost of small, special seed collec- 

 tions often precludes use of local seeds in fa- 

 vor of cheaper, nonlocal ones of relatively few 

 species (31,54). Western nurseries and the Soil 

 Conservation Service's Plant Material Centers 

 have responded to the demand for more native 

 plants, but many species still are not available 

 commercially. For many that are available, 

 germplasm is limited to specialized ecotypes 

 or registered cultivars with limited value for 

 restoration. 



The cost of reclamation varies greatly, de- 

 pending on the extent of disturbance, the ex- 

 tent of restoration, and the type of ecosystem. 

 The average cost of seeding for reclamation of 

 surface mines in seven Western States has been 

 estimated at $620 per hectare (in 1977 dollars) 

 (59). This estimate included fertilization, mulch- 

 ing, and irrigation (the most expensive com- 

 ponent). The cost of earth-moving brought the 

 total bill to $10,000 per hectare. Mechanical 



planting of shrubs costs from $500 to $2,000 

 per hectare in Utah, depending on whether 

 bareroot or containerized stock was used (20). 

 Hand-planting to simulate natural vegetation 

 patterns would further increase costs. 



Establishing the same community that oc- 

 curred on a site prior to disturbance is often 

 not feasible because of the high cost and a lack 

 of information regarding, for example, neces- 

 sary conditions for seed germination and other 

 aspects of survival and reproduction of native 

 species. Although restoration technologies can- 

 not quickly restore the diversity that existed be- 

 fore degradation, they can be used to break the 

 cycle of resource degradation and to reestab- 

 lish a community of indigenous organisms. 

 Normal plant and animal succession may even- 

 tually lead to a self-sustaining and relatively nat- 

 ural ecosystem that provides most of the values 

 of biological diversity. 



OUTSIDE PROTECTED AREAS 



Most of the discussion thus far has dealt with 

 protected areas where maintaining biological 

 diversity is a management objective. But the 

 majority of biological resources are found out- 

 side these areas. Few strategies have been de- 

 signed yet for conserving diversity in nondesig- 

 nated areas. Various resource conservation 

 techniques with other objectives serve to en- 

 hance iDiological diversity, however. 



Genetic Resources for Agriculture 



Conservation of genetic variability outside 

 protected areas is especially important because 

 so many crop varieties and livestock species 

 and many of their wild relatives are not found 

 in areas designated for protection. In addition, 

 evolutionary processes, such as crop-pest and 

 crop-pathogen interactions, can continue. This 

 type of conservation occurs when farmers have 

 chosen to maintain traditional crop varieties 

 and livestock breeds. 



Crop varieties with a broad genetic base and 

 wild relatives of crop plants are mainly located 



where traditional farming practices prevail. 

 Large proportions of these resources (50 per- 

 cent or more for many species) have not yet 

 been evaluated or collected for preservation off- 

 site (50). Germplasm collection programs focus 

 on the world's major staple crops, so many spe- 

 cies that are not yet widely grown are unhkely 

 to be preserved offsite. Both these and local va- 

 rieties of major crops are threatened with ex- 

 tinction as they are replaced by modern vari- 

 eties, which the economics of agriculture favor. 



A diverse mix of local varieties theoretically 

 protects traditional farmers from catastrophic 

 crop losses. And, with locally adapted varieties, 

 farmers depend less on subsidized inputs, such 

 as pesticides, fertilizers, irrigation equipment, 

 and processed animal feed. In many countries, 

 traditional farmers appear to be motivated more 

 by avoiding risk than by maximizing profit. 

 Nevertheless, as agricultural development oc- 

 curs, farmers are shifting to fewer varieties, 

 modern methods, and higher profits. 



One response to this trend is the recently 

 established program to monitor the remaining 



