CD-ROM search service The provision of special aid by library staff trained to query bibliographic or other information contained on an electronic storage medium, usually to meet the research needs of the library's clients
soil function The main soil function is participation in the material transformation and migrating processes occurring in the natural environment on which the functioning of ecosystems depends. The most active participants in the occurring processes are microorganisms and invertebrates, whose activity, different variety, complex structure, and abundance accurately reflect the soil type and its characteristics: so they are important indicators of ecological stability. The variety of soil organisms determine its self-regulatory and self-cleaning capacity