About earthworm communities in a rain forest and an adjacent pasture in Peru

Earthworms were collected from a primary forest and a four-year-old pasture near Panguana Biological Station (Dpto. Huánuco, Peru). The sites are located in the preandine zone of the Peruvian rain forest, where the forest is being increasingly replaced by pasture. It can be expected that the soil fauna changes accordingly. This is shown by the earthworm community. In the litter layer of the primary forest, mainly epigeic species of Glossoscolecidae of Neotropical distribution were found. In the pasture in contrast, the peregrine glossoscolecid, Pontoscolex corethrurus, is dominant, a species that inhabits the mineral layer of the soil. The total abundance of worms decreased in the pasture to about one half of that in the forest. These results are compared with data available from other rain forest, savanna and pasture sites

Assessment of ecotoxicological effects of pesticides on the soil fauna and soil processes under tropical conditions.

The work reported here is planned for the SHIFT project "Management of plant residues and its effect on decomposition and soil fauna in central Amazonian agroecosystems"

Effects of three pesticides on the avoidance behavior of earthworms in laboratory tests performed under temperate and tropical conditions.

Little research has been performed on the impact of pesticides on earthworms under tropical conditions. Taking into consideration the oftenlimited resources in tropical countries, simple screening tests are needed. Therefore, it was investigated whether three pesticides relevant for the Brazilian Amazon (benomyl, carbendazim, lambda-cyhalothrin) affect the avoidance behavior of the earthworm Eisenia fetida. The tests were performed for two days according to ISO guideline 17512 but were adapted to tropical conditions (i.e. test substrate, test organism and temperature). The results indicate that this test gives reproducible and reliable results. Toxicity values (NOEC, EC50) are lower than those determined in 14 day-acute mortality tests and are approximately in the same range such as those found in 56 day-chronic reproduction tests with the same earthworm species, which were performed in parallel. Therefore, the use of the earthworm avoidance tests is recommended as a screening tool for the risk assessment of pesticides

The effects of the insecticide lambda-Cyhalothrin on the earthworm Eisenia fetida under experimental conditions of tropical and temperate regions.

Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28 °C) and with two strains (temperate and tropical) of the compost worm Eisenia fetida. The insecticide was spiked in two natural soils, in OECD artificial soil and a newly developed tropical artificial soil. The effects of lambda-Cyhalothrin did rarely vary in the same soil at tropical (LC50: 68.5?229 mg a.i./kg dry weight (DW); EC50: 54.2?60.2 mg a.i./kg DW) and temperate (LC50: 99.8?140 mg a.i./kg DW; EC50: 37.4?44.5 mg a.i./kg DW) temperatures. In tests with tropical soils and high temperature, effect values differed by up to a factor of ten

State of the science and the way forward for the ecotoxicological assessment of contaminated land.

Durante as últimas duas décadas, ecotoxicologistas de solo têm feito progressos ao utilizar conceitos básicos e avanços da zoologia e ecologia do solo. Os métodos existentes têm sido aplicados, e têm-se desenvolvido novas ferramentas para avaliar de que modo a contaminação química pode afetar o ecossistema terrestre, inclusive pela degradação ou destruição da qualidade do solo e dos habitats ou pela redução da biodiversidade edáfica. Os ecotoxicologistas de solo utilizam um conjunto de protocolos padronizados, originalmente desenvolvidos como testes de laboratório com compostos químicos simples como os pesticidas e, posteriormente, adaptados em termos de abordagens e métodos, para a avaliação de áreas contaminadas. No entanto, a relevância ecológica de algumas abordagens permanece questionável. Neste artigo, os autores discutem os recentes desafios para uma avaliação ecotoxicológica coerente do ecossistema solo em áreas contaminadas e apresentam recomendações de como integrar os efeitos das propriedades físicoquímicas do solo, as variações na diversidade de invertebrados do solo e, as interações entre organismos dos vários níveis tróficos. São analisadas novas abordagens e métodos de avaliação, usando-se exemplos de três continentes (particularmente o trabalho desenvolvido no Brasil), e são dadas recomendações de como aumentar a relevância ecológica na avaliação ecotoxicológica de áreas contaminadas

Structure and function of soil fauna communities in Amazonian anthropogenic and natural ecosystems.

The aim of our study was to judge the soil biological conditions in the plantations with regard to the aspired sustainability of agricultural and forestry systems

Exposition bodenbewohnender Invertebraten gegenüber Antiparasitika

Innerhalb der Antiparasitika gilt Ivermectin (IVM), das zur Gruppe der Avermectine gehört, als einer der bedeutendsten Wirkstoffe und wird seit über 35 Jahren auch in der Veterinärmedizin gegen Endo- und Ektoparasiten eingesetzt. Die Aufklärung der Pharmakokinetik in Tieren ist Gegenstand aktueller Forschung, wobei für Nutztiere bekannt ist, dass IVM nach verabreichter Dosis langsam und überwiegend unverändert mit dem Kot ausgeschieden wird. Da Gülle und Dung behandelter Tiere den Vektor für die IVM-Verbreitung bei veterinärmedizinischer Anwendung darstellen, sind zunächst Bodenorganismen betroffen, und aktuelle Untersuchungen zeigen, dass IVM-Rückstände grundsätzlich die Biodiversität von Dunginsekten-Gemeinschaften reduzieren können. Da IVM schlecht wasserlöslich ist, kann es potenziell an Böden und Sedimente adsorbieren und in Gewebe übergehen und sich so zusätzlich zu einer möglichen Toxizität in Nichtzielorganismen und Nahrungsketten anreichern. Das Promotionsvorhaben soll neuartige Erkenntnisse über das Verhalten von IVM und anderen Antiparasitika in bodenbewohnenden Invertebraten liefern. Die Ergebnisse aus standardisierten Toxizitätstests mit Regenwürmern sollen eine Grundlage für eine umfangreichere Umweltrisikobewertung der Wirkstoffe bilden. Eine spezifische chromatographische Analytik der relevanten Einzelsubstanzen im Bodenmedium und in den Testorganismen ergänzt die Untersuchung und soll Hinweise auf den Eintrag und eine mögliche Anreicherung der Antiparasitika in den Regenwürmern liefern. Da diese eine wichtige Rolle in Stoffkreisläufen im Boden spielen und einen hohen ökologischen Wert aufweisen, ist die Frage nach der Wirkung belasteter Böden auf sie von hoher Relevanz