Klaus Dieter Sautter

No-tillage greatly increases earthworm populations in Paraná state, Brazil

Summary No-tillage (NT) agroecosystems now occupy >18 million ha in Brazil, of which 5 million are in the state of Parana, where NT began in the early 1970’s. The first NT farmers created an association to promote their practices, the ‘Clube da Minhoca’ (Earthworm Club), thus named because of the observed increase in earthworm numbers in their fields after adopting NT. However, little data were available on the topic until 1996, when more intensive studies began near Londrina, in N Parana. Earthworms were sampled by hand-sorting soil monoliths (25 × 25 cm square, 30‐40 cm depth) at 8 sites, comprising various natural and agricultural land-use and management systems. Data from the literature were collected from a further 6 sites for comparative purposes. The results for N Parana confirm the presence of higher earthworm populations under NT (46‐116 indiv., 0.49-1.06 g f.wt. m-2; mean values in dry-wet seasons, respectively), minimum tillage (42‐179 indiv., 0.68‐1.05 g f.wt. m -2 ), pastures (48‐182 indiv. m -2 ) and native forests (16‐42 indiv., 1.56‐0.83 g f.wt. m -2 ) than under conventional tillage (13‐22 indiv. and 0.13‐0.02 g f.wt. m-2). Soil disturbance thus had a negative impact on earthworm populations, and significant positive relationships were observed between earthworm abundance and age of NT systems, as well as with soil % C. In the Londrina area, some species present in the primary forests were absent in NT, where most earthworms were small-sized endogeic or epi-endogeic species. These results contrasted greatly with those from the cooler region in E Parana, where the exotic epi-endogeic Amynthas spp. dominated, reaching high densities (up to >100 indiv. m-2) and biomass (up to >30 g f.wt. m-2), especially under NT. Given the high abundance of worms under NT, further work should focus on estimating their potential contributions to soil processes, fertility and plant production in these systems.

Carbofuran effects in soil nematode communities: using trait and taxonomic based approaches.

This work intends to implement the use of native soil nematode communities in ecotoxicological tests using a model pesticide and two geographically nematode communities (Mediterranean and sub-tropical) in order to obtain new perspectives on the evaluation of the toxic potential of chemical substances. The environmental condition of the nematode communities was described using a trait-based approach (grouping the organisms according to their feeding traits) and a traditional taxonomic method (identification to family level). Effects on total nematode abundance, number of families and abundance of nematode feeding groups as well as potential shifts in both trophic and family structure were assessed. Agricultural soils from Curitiba (Brazil) and Coimbra (Portugal) were sampled and the corresponding nematode communities were extracted. Part of the collected soil was defaunated and spiked with four doses of a carbofuran commercial formulation. Afterwards each of the replicates was inoculated with a nematode suspension containing ≈200 or 300 nematodes. After 14 and 28 d of exposure the nematodes were extracted, counted and identified at family level and separately classified according to their feeding traits. The patterns of nematode responses revealed a decrease in the total abundance and a reduction in the number of families. Despite the similar effects observed for both communities, statistically significant toxic effects were only found within the Portuguese community. The total nematode abundance was significantly reduced at the highest carbofuran concentrations and significant shifts in the family structure were detected. However, the trophic structure, i.e., the contribution of each feeding group for the overall community structure, did not significantly change along the contamination gradient. Results showed that using such a trait-based approach may increase the ecological relevance of toxicity data, by establishing communalities in the response to a chemical from two different taxonomic communities, although with potential loss of information on biodiversity of the communities.

Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil

Aminomethylphosphonic acid (AMPA) - one of glyphosate’s main metabolites - has been classified as persistent in soils, raising concern regarding the widespread use of glyphosate in agriculture and forestry. Glyphosate may have negative or neutral effects on soil biota, but no information is available on the toxicity of AMPA to soil invertebrates. Therefore our aim was to study the effect of AMPA on mortality and reproduction of the earthworm species Eisenia andrei using standard soil ecotoxicological methods (ISO). Field-relevant concentrations of AMPA had no significant effects on mortality in acute or chronic assays. Except at the highest concentration tested, a significant biomass loss was observed compared to controls in the chronic assay. The number of juveniles and cocoons increased with higher concentrations of AMPA applied, but their mean weights decreased. This mass loss indicates higher sensitivity of juveniles than adults to AMPA. Our results suggest that earthworms coming from parents grown in contaminated soils may have reduced growth, limiting their beneficial roles in key soil ecosystem functions. Nevertheless, further research is needed to better understand the mechanisms underlying the sublethal effects observed here.

IMPACTOS AMBIENTAIS NA ÁREA DE PROTEÇÃO AMBIENTAL (APA) DE GUARATUBA, PARANÁ, BRASIL, SOB O PONTO DE VISTA DE MORADORES TRADICIONAIS

The present research was carried out in the Environmental Protection Area (APA) of Guaratuba, State of Parana, to analyze the environmental impacts of the APA as assessed by the local traditional communities. Two instruments were used: Geographical Information System (GIS) and Discourse of the Collective Subject (DSC). Although the GIS covers more situations that the DSC, results were similar. The pressures are complex and the analysis must involve the natural and traditional communities.

ISO 14001: implementar ou não? Uma proposta para a tomada de decisão

One of the difficulties of the decision making process, is that many entrepreneurs may find themselves incapable of finding enough subsidies for the decision of adopting or not the ISO 14001 standard. This work presents a tool that facilitates corporate decision making, providing a thorough analysis of the real necessity and feasibility of the implementation of the ISO 14001 standard and its certification. This tool consists of a multicriterial analysis, in which is possible to verify the compatibility between the organizational profile and the ISO 14001 standard. This recommendation of adopting or not the ISO 14001 standard seeks to facilitate the organization decision making; and, as a result, it also enhances the probability of the organization attaining its objectives. This tool presented a strong applicability when implemented in two companies.

Earthworm species in public parks in Curitiba, Paraná, Brazil

Earthworms are important macroinvertebrates that provide soil ecosystem services and are also useful environmental bioindicators. Urban areas around the world have major impacts on biodiversity and the objective of the present study was to assess the role of urban parks of Curitiba, Paraná State, in preserving native earthworm species. Earthworm populations were sampled in five parks (Barigui, Tingui, Barreirinha, Passaúna and the Botanic Garden), in two land use systems (grass lawns and secondary forest fragments) in two seasons, summer (November 2013) and winter (June 2014). A total of twelve earthworm species were identified, belonging to six families: Glossoscolex sp.1, Fimoscolex sp.1, sp.2 and sp.3 (Glossoscolecidae), Pontoscolex corethrurus (Rhinodrilidae), Eukerria tucumana (Ocnerodrilidae), Amynthas gracilis, Amynthas corticis, Metaphire californica (Megascolecidae), Aporrectodea rosea and Lumbricus rubellus (Lumbricidae), the latter being the first record for this species in Brazil. In addition, a single unidentified juvenile Dichogaster sp. (Acanthodrilidae) was found. Four new species were found and three out of five urban parks of Curitiba (especially the Botanic Garden) were able to preserve native species, though their abundance was low and exotic species (n=8) predominated, attributed to human disturbance that favors invasion and colonization of exotic earthworms.