Abstract In Brazil, innumerable regions of native landcover have been removed and replaced by agricultural cultivation, especially of sugarcane. In this culture, the application of fertilizers containing metals has caused impacts on the water resources causing contamination of stream sediments and occasioning bioaccumulation of metals in aquatic invertebrates. In the year of 2006, an environmental diagnosis of metals in sediments of streams located near sugarcane cultivation areas and in streams located in preserved areas, was published. That study pointed to high concentrations of metals in stream sediments in agricultural areas. These streams have been monitored over the last 10 years conducting analyses of metals and monitoring possible changes in land use. In the present paper, a historical comparison of metals contamination in the sediments of the same streams is conducted, aiming to present a status of 10 years later, analyzing 5 metals (Zn, Cd, Mn, Cr and Fe) found in the sediments of 8 streams, five located in areas of sugarcane cultivation and three located in preserved areas. This study also shows that there is higher concentration of metals in the sediments of streams near sugarcane cultivation than in preserved areas. The temporal historical evaluation showed high concentrations of Cd in 2016 when compared to the year 2006 for streams near sugarcane cultivation.

Este artigo analisou a relação entre mesohabitats e as espécies de oligoquetos aquáticos no Córrego Galharada (Parque Estadual de Campos do Jordão, Estado de São Paulo, Brasil). Entre agosto de 2005 e maio de 2006 um total de 192 amostras foram obtidas em quatro mesohabitats diferentes: folhiço em corredeiras (RL), folhiço em remanso (PL), sedimentos em remanso (PS) e sedimento intersticial de pedras em corredeiras (IS). Nos mesohabitats amostrados, foram identificados 2007 espécimes, pertencentes a duas famílias (Naididae e Enchytraeidae). Entre os oligoquetos identificados, Naididae foi representada por seis gêneros (Allonais, Chaetogaster, Nais, Pristina, Aulodrilus e Limnodrilus). A Análise de Componentes principais (ACP) revelou que os dois primeiros eixos explicaram 85,1% da variabilidade total dos dados. Limnodrilus hoffmeisteri Claparede, 1862 e Aulodrilus limnobius Bretscher, 1899 foram associadas às areas de remanso (PL e PS). A maioria das espécies dos gêneros Pristina e Nais demonstrou aparente afinidade com mesohábitats de corredeira. A análise de espécies indicadoras (IndVal) revelou que Nais communis Piguet, 1906, Pristina leidyi Smith, 1896 and Pristina (Pristinella) jenkinae (Stephenson, 1931) são indicadoras do mesohábitat RL, enquanto a família Enchytraeidae foi considerada indicadora do mesohábitat PL.

This paper analyses the relationship among mesohabitat and aquatic oligochaete species in the Galharada Stream (Campos do Jordão State Park, state of São Paulo, Brazil). Between August 2005 and May 2006 a total of 192 samples were obtained in areas of four different mesohabitats: riffle leaf litter (RL), pool leaf litter (PL), pool sediment (PS) and interstitial sediment from rocky beds in riffle areas (IS). In the mesohabitats sampled, 2007 specimens were identified, belonging to two families (Naididae and Enchytraeidae). Among the oligochaetes identified Naididae was represented by six genera (Allonais, Chaetogaster, Nais, Pristina, Aulodrilus and Limnodrilus). Principal components analysis (PCA) revealed the first two axes explained 85.1% of the total variance of the data. Limnodrilus hoffmeisteri Claparede, 1862 and Aulodrilus limnobius Bretscher, 1899 were associated with the pool areas (PL and PS). Most species of genera Pristina and Nais demonstrated apparent affinity with the riffle mesohabitats. The Indicator Species Analysis (IndVal) revealed that Nais communis Piguet, 1906, Pristina leidyi Smith, 1896 and Pristina (Pristinella) jenkinae (Stephenson, 1931) are indicative of RL mesohabitat, while family Enchytraeidae was considered indicative of PL mesohabitat.

A família Ampullaridae, pertencente à classe Gastropoda, é caracterizada por organismos de água doce com ampla distribuição na região tropical. Vermes Oligochaeta associados a esses caracóis podem ser encontrados habitando o umbílico de suas conchas. Devido à carência de informação sobre a ecologia desses vermes, o presente trabalho centrou-se em um levantamento de espécies de Oligochaeta associadas ao molusco Pomacea bridgesii (Reeve, 1856). Em amostragens realizadas no inverno e na primavera de 2003 e no verão de 2004, foram observados 209 caracóis, sendo que somente em 58 deles foi detectada a presença de vermes Oligochaeta, correspondendo a uma incidência de 27,75%. Foram encontrados, no total, 89 oligoquetos, todos da família Naididae. As espécies Haemonais waldvogeli Bretscher, 1900, Dero (Dero) nivea Aiyer, 1929 e Dero (Dero) sawayai Marcus, 1943 apresentaram a maior abundância relativa (43,68%, 12,32% e 10,08%, respectivamente). Espécimes de Haemonais waldvogeli foram encontrados em todos os períodos sazonais, o que demonstra sua afinidade com este tipo de substrato. Os resultados indicam que várias espécies de Naididae encontram no umbílico da concha (que contém detrito fino) um habitat favorável para seu estabelecimento.

The family Amplullaridae belongs to this class Gastropoda and is made up of freshwater organisms with a wide geographical distribution in tropical regions. Oligochaeta worms can be found in association with snails of this family, inhabiting the umbilicus of their shells. Due to the lack of information on the ecology of these worms, this work focused on investigating which kind of Oligochaeta species associate with the mollusk Pomacea bridgesii (Reeve, 1856). Samples were collected during winter and spring 2003 and summer 2004. From a total of 209 snails collected, the presence of Oligochaeta worms was observed in only 58 of them (27.75%). In these infected snails, 89 Oligochaeta worms were found, all belonging to the family Naididae. The species Haemonais waldvogeli Bretscher, 1900, Dero (Dero) nivea Aiyer, 1929 and Dero (Dero) sawayai Marcus, 1943 were the most abundant (43.68%, 12.32% and 10.08%, respectively). Haemonais waldvogeli was found in all of the seasons studied, what demonstrates its affinity for this kind of substrate. The results indicate that several Naididae species find in the umbilicus of these snails's shells (which contains fine detritus) a favorable habitat for establishing themselves.