Perhaps Bruce could fill us in on earthworms, since not all of us are knowledgable in this area (I'm a marine ecologist and obviously picked up on some inaccurate ideas). I always assumed that they played the same role as some key polychaetes do in benthic systems, where it has been shown that if just one key species is eliminated the bottom turns to concrete.
So please: if earthworms are absent, what keeps the soil aerated and broken up? What are the detrimental impacts of the undesirable earthworm species? What is the range of ecosystem functions that earthworms play? Bill Silvert ----- Original Message ----- From: Bruce A. Snyder To: William Silvert Cc: [email protected] Sent: segunda-feira, 3 de Maio de 2010 18:41 Subject: Re: [ECOLOG-L] State Microbes and Yucky Worms Native Nearctic earthworms have not been eliminated and are quite diverse. Pleistocene glaciations did extirpate them from the northern portion of the continent, and the present-day ecosystems in this region developed just fine without the presence of earthworms. This is where the detrimental impacts of invasive earthworms are the most prominent. European earthworms are the primary culprits in the northern forests, but Asian, African, and South American species have all found there way to North America. Collective nouns are not a problem in themselves, but it is troublesome when a collective term is applied to describe the homogeneity of something that is far from homogeneous. E.g., not all earthworm individuals are the same species and as such not all function the same; not all earthworm species are beneficial in all locations.
