The earthworm (Aporrectodea caliginosa) primes the release of mobile and available micronutrients in soil

The interactions between soil type and earthworm species determine the properties of earthworm casts

“…In our experiment, earthworms did not significantly increase the Mn content in casts compared to the control, except for L. terrestris that tended to increase the Mn content and A. rosea that decreased it. Similarly, Bityutskii et al (2012) found a decrease of Mn content in casts of A. caliginosa when no litter was added. We found no significant difference in Na content between the control soil and the casts in the Rendosol, like Basker et al (1994) in the sandy soil.…”

“…The increase in mineral nitrogen in earthworm casts has been largely reported, especially for the ammonium content of fresh casts (Aira et al, 2003;Bityutskii et al, 2012;Decaëns et al, 1999). High levels of NH 4 + and NO 3 − in casts are due to the ingestion of organic matter that is either directly processed by earthworms or by the earthworm microflora through a "priming effect" (Lavelle et al, 1995).…”

Non-native earthworms promote plant invasion by ingesting seeds and modifying soil properties

“…Earthworms in turn also significantly impact soil physical, chemical, and microbiological properties (Bityutskii et al, 2012;Huang et al, 2010;Lavelle et al, 1998;Lee, 1985). We found that the increased abundance of earthworms was not only correlated with higher NO 3 À and soil moisture but also with a higher germination of non-native seeds in the casts tested.…”

“…This ingestion is often species-specific with earthworms selecting seeds according to traits such as size or oil content (Clause et al, 2011;Grant, 1983) or by plant functional groups (Milcu et al, 2006;Zaller and Saxler, 2007). Seedlings that emerge from casts are likely to benefit from their higher nutrient content and physical protection (Bityutskii et al, 2012;Deca€ ens et al, 2003;Zhang and Schrader, 1993). The outcome in terms of seedling growth and survival should depend on the combination of plant and earthworm species (Eisenhauer et al, 2009a;Milcu et al, 2006).…”

Effects of cast properties and passage through the earthworm gut on seed germination and seedling growth

“…Earthworms impact plant communities both through the modification of soil chemical, physical and microbiological properties (Bityutskii et al, 2012;Scheu, 2003;Zhang and Schrader, 1993) and through seed ingestion (see Forey et al, 2011 for a review).…”