Soil teeming with life: new frontiers for soil science.

Abstract

The soil environment is arguably the most complex biological community because of the extremely high diversity at small scales and a chemical environment of complex and changing gradients housed in a heterogenous physical environment. Some basic important facts regarding the complexity of soil communities are presented. For a better understanding of the soil community and its activity, the role of soil matrix in structuring microbial communities, geographical characteristics of heterotrophic communities, and the application of DNA microarray technology to environmental microbiology are discussed. The highlights of soil organic matter research within the soil science community and the inter-disciplinary nature of soil science per se, is briefly reviewed and the main conclusions are outlined.

Linking Species Richness, Biodiversity and Ecosystem Function in Soil Systems

“…Bacteria are probably the most speciose array of organisms on earth (Tiedje et al, 2001 ; Torsvik and 0vre5s, 2002). In addition, they are undoubtedly the most numerous organisms on earth, and have been estimated to number from 4 to 6 x lo3* cells, with a sizable proportion, about 92%, being in the subsurface, which includes the earth's mantle to 4 km.…”

Development and Evaluation of Functional Gene Arrays for Detection of Selected Genes in the Environment

“…In environmental studies, the target and probe sequences can be very diverse (29), and it is not clear whether the performance of microarrays with diverse environmental samples is similar to that with pure culture samples and how sequence divergence affects microarray hybridization. Also, environmental samples generally contain humic acid and other organic materials, which may inhibit DNA hybridization on microarrays (19,21).…”

Microbial Diversity: Relevance and Relationship Between Environmental Conservation And Human Health

“…The observation in the increase of degraded agricultural areas has led to a change in the concept of land use, based on a holistic view of the agricultural process, where natural resources (soil, water and biodiversity) are exploited more sustainably. The diversity of microorganisms as an indicator of the quality of agroecosystems has been widely debated, especially in the last decade, with the advent of molecular biology techniques that have favored the evaluation of microorganisms in environmental samples (Coutinho et al 1999;Tiedje et al 2001;Unicomb et al 2005). The main argument in favor of such environmental feature is the fact that the microbial diversity naturally remains unchanged throughout the year (Dickens and Anderson 2001).…”