Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables
- Published
- Accepted
- Subject Areas
- Agricultural Science, Ecology, Ecosystem Science, Environmental Sciences
- Keywords
- soil use intensity, soil ecology, soil biota, earthworm, soil community structure, Soil sustainability
- Copyright
- © 2014 Falco et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ PrePrints) and either DOI or URL of the article must be cited.
- Cite this article
- 2014. Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables. PeerJ PrePrints 2:e722v1 https://doi.org/10.7287/peerj.preprints.722v1
Abstract
The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological variables that are associated to the observed differences in earthworm assemblage structure between soils. Three soil uses were evaluated: 1- Fifty year old naturalized grasslands; 2- Cattle-grazing fields converted to feedlot within the two years before the start of this work, and 3- Fifty year old intensive agricultural fields. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in their relative abundances according to the system. The results show that earthworm community structure is linked to and modulated by soil properties. Both, species abundance and diversity showed significant differences depending on soil use intensity. A PCA analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance Systems. Microscolex dubius was shown to be related to the naturalized grasslands and it was associated to Ca, pH, Mechanical Resistance, and to respiration. Aporrectodea caliginosa was related to high K levels, low enzymatic activity, slightly low pH, and low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found un the cattle-grazing system, were related to high soil humidity, low pH, low Ca and low enzymatic activity. These results show that earthworm assamblages can be good descriptors of different soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different temporal patterns and species associations, due to the changes in soil properties attributable tos oil use intensity.
Author Comment
Biological indicators of ecosystem state are of increasing use in aquatic ecosystems, but their development for terrestrial ecosystems lags somewhat behind. This manuscript addresses the important issue of assessing changes on earthworm assamblages in different agroecosystems. The work presented here provides information about earthworm assamblage structure being sensitive to the different uses of the same soil. Our data shows that, as soil use intensity has a strong effect on soil´s physical, chemical, and microbiological parameters, those parameters in turn, are related to earthworm species richness and abundance. In this way, our manuscript provides hard data supporting that earthworm assemblage structure is a good descriptor of the functioning of the edaphic environment. The data also shows that earthworm assamblage structure can be tracked in such a way so as to provide information for soil health monitoring over a wide range of anthropogenic intensities of soil use.
Supplemental Information
Dataset for Falco et al
Complete dataset of all samplings with details on agroecosystem, numbers of individuals collected from each earthworm species and genus and all physical, chemical and biological data related to all the analyses presented