Data/hora: 10/06/2024 04:58:57

Biblioteca(s): | Embrapa Florestas.
Data corrente: | 03/10/2008
Data da última atualização: | 03/10/2008
Autoria: | LÓPEZ, M. G.; SALMON, S.; AZA, D. T.; FERNANDEZ, R.
Título: | THE EFFECT OF THE EARTHWORM Hormogaster elisae ON THE ABUNDANCE OF THE COLLEMBOLA Heteromurus nitidus IN SOIL FROM EL MOLAR (MADRID).
Ano de publicação: | 2008
Fonte/Imprenta: | In: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM.
Idioma: | Inglês

Conteúdo:

Several authors (Maraun et al. 2001, 2003; Migge, 2001) have reported the negative influence
of earthworms on the communities of microarthropods. The same trend has been reported for
the endogeic Hormogaster elisae at El Molar (Madrid, Spain) by Gutiérrez et al., 2003. Other
studies showed the favourable impact of earthworms on several arthropods species (Loranger
et al 1998, Salmon and Ponge, 1999). The collembolan Heteromurus nitidus was reported to be
more abundant in soils with the anecic earthworms Aporrectodea giardi and Lumbricus terrestris
(Salmon and Ponge, 1999; Salmon, 2004; Salmon et al., 2005).
The objective of the present study was to know if H. elisae (previously proved to negatively affect
the microarthropod densities) produce attractive galleries for H. nitidus (usually attracted to
earthworms galleries) or whether this collembolan species is also repelled by the soil disturbance
generated by H. elisae.
Six microcosms (plastic boxes of 18x12x6.5 cm) divided in two compartments with a 2mm
pore-size mesh in the middle, were used. The mesh allowed H. nitidus to move around freely,
from one compartment to another, but prevented the motion of earthworms. The microcosms
were filled with soil from El Molar (Madrid) (400g in each compartment), and maintained at
15ºC and 20% humidity for 15 days. Two worms were placed in one of the compartments from
each microcosm and 28 H. nitidus (14 in each compartment) were introduced in each microcosm.
Another six control microcosms were set up with the same structure but without earthworms.
After the 15 days had elapsed, the microcosms were disassembled and the Collembola
occurring in the soil from the both compartments were extracted separately with the Berlese-
Tulgren method. They were then counted under a stereomicroscope, distinguishing adult and
juvenile individuals. A paired t-test was performed to compare the mean number of Collembola
in each compartment.
No significant differences were observed between the soil with or without earthworm, nor in
adult H. nitidus, nor in juveniles. Two hypotheses may explain this result: (1) H. elisae has actually
no influence on the behaviour and the survival of H. nitidus or (2) the positive effects would be
counterbalanced by the negative ones, leading to the absence of visible effects of this earthworm
specie on the collembolan H. nitidus. In fact, H. nitidus could have been attracted to the casts,
mucus and urine from H. elisae, as it was to A. giardi excreta (Salmon and Ponge, 2001), and,
in the same time, disturbed by the physical movement of the earthworm, or by a competition for
food resources as it has been suggested in Gutiérrez et al. (2006).

Categoria do assunto: | --
Registro original: | Embrapa Florestas (CNPF)
Exemplares: | CNPF - (43797-1) - UPE - PL - -- - CD0305 -  -  - DIS