15th International Colloquium on Soil Zoology
12th International Colloquium on Apterygota

CURITIBA - PR - BRAZIL

Much beyond being only substrates for growing plants, soils are living entities and the home of numerous organisms whose diversity may even surpass that of the aboveground flora and fauna. Soils are among the most biologically rich habitats on earth; nowhere in nature are species so densely packed as they are in soil communities. For example, a single gram of soil may contain millions of bacteria and several thousand species of microorganisms, while soils of tropical forest habitats (e.g., Amazonian or Atlantic Rainforests) may harbor more than 2200 species of soil invertebrates in a single site. Of these, the vast majority is likely to be nematodes and insects, each representing more than 100 species.

In fact, over 1 million species of insects may inhabit Brazilian ecosystems, and a large proportion (up to 25% or more) of these may be associated with soils for an important part of their life cycle. More than 50,000 species of soil+litter inhabiting animals have been described from Brazil, being the beetles, Protozoa, spiders, nematodes, ants, and mites the most diverse, each with >1,000 classified or estimated species. However, most groups of soil animals remain poorly known, and their species diversity is certainly much larger than the currently known totals. Further efforts are urgently needed to overcome the taxonomic challenges involved in describing the world’s soil biota, especially considering the potential negative impacts on global biodiversity of climate and further land use changes worldwide.

Soil animals perform various ecosystem services and key functions in both natural and agricultural ecosystems including biocontrol of pests and diseases, decomposition of organic matter, cycling of nutrients and C sequestration. Soil formation and physical properties are affected by bioturbation. Some soil animals (e.g., snails, earthworms, ants, termites, beetle grubs, caterpillars) are important sources of food for indigenous human societies. Many insects that often spend a critical stage of their life cycle within the soil or on its immediate surface are important plant pollinators. The activity of soil animals can also significantly influence plant growth, both positively and/or negatively (pests). Finally, soil animals and their biodiversity have also been widely used as bioindicators of soil quality. In fact, the value of the ecosystem services provided each year by the soil biota worldwide might exceed US $1.5 trillion.

Therefore, proper management practices, in particular those that preserve and enhance the litter layer, protect the soil’s physical integrity, minimize the use of external synthetic inputs (especially pesticides), and enhance soil organic resources will be the most interesting to promote soil animal activities and their beneficial role in soils.

These are just some of the issues that will be discussed in the upcoming XV International Colloquium on Soil Zoology and XII International Colloquium on Apterygota, that will be held in Curitiba, Brazil, from 25 August to 3 September, 2008. As the organizers of the 15th ICSZ and 12th ICA, we invite you to participate and look forward to seeing you in Brazil in 2008.

George G. Brown, Researcher, Embrapa Florestas
Klaus D. Sautter, Professor, Universidade Positivo (UP)