Global panorama of studies about freshwater oligochaetes: main trends and gaps

Freshwater oligochaetes have been studied over the years in a wide range of habitats around the world. To analyse the data published about freshwater oligochaetes in the 31 year period between 1985 and 2015, we searched for documents in the ISI Web of Science, Scopus and SciELO databases. A total of 979 works were evaluated from 184 periodicals. The United States is the country with the most publications about aquatic oligochaetes, followed by France, Germany and Italy. Works related to the ecology and ecotoxicology of these organisms are most abundant. Studies carried out in the laboratory are most frequent, consisting of investigations involving bioassays, morphology, genetics and molecular biology. The results also show that spring, cave water bodies and swamps have been studied less than any other aquatic habitat and that countries of the Southern Hemisphere are under-represented in the studies of aquatic oligochaetes. Hence, there is a need for increased efforts to fill in gaps in the knowledge about these oligochaetes

Nascentes de Mata Atlântica: panorama e ecologia da fauna de Oligochaeta (Annelida) e implicações para conservação

Springs are important landscape elements due to its economic, social and ecological importance. In view of the increasing degradation of these ecosystems, added to low knowledge about their biodiversity in tropical regions, the main goal of this study is to increase the knowledge about springs in tropical regions and to provide information on the diversity and ecological aspects of aquatic oligochaetes in this ecosystem. To confirm the lack of studies in springs, specifically considering freshwater oligochaetes, a bibliographic survey has was made basead on the studies carried in a period of 30 years (1985-2015) in various continental aquatic environments around the world. The survey showed that spring are one of the least studied ecosystems, together with cave water bodies and swamps. For this study, fauna was collected, physical and chemical variables were measured, and a rapid assessment protocol (RAP) were applied at spring located in different cities of Minas Gerais State, either in Conservation Units or in public and private areas. The results showed differences among the oligochaetes species composition found in spring that rises diffusely forming a flooded area (helocrene), in comparasion to spring that forms streams (rheocrene) and that ones that forms a pond (limnocrene). Probably, it is due to the high heterogeneity of this kind of spring. We also verified that beta diversity was high at the three types of springs, suggesting that efforts to conserve these ecosystems should include many spring systems of all types. After applying RAP, this study emphasized that, besides the major numbers of spring, water have been classified as optimum also the springs located in urban areas were classified as moderate or poor, even when some of them were located in Conservation Units. This result highlights importance of Conservation Units on spring preservation, and also the vulnerability of these systems when inserted in urban environments. This study contributes not only for academic knowledge, but also for environmental management, once it points out the habitats and places that need more studies, showing the importance of preserving different types of spring systems for the maintenance of diversity. It also indicate the requirements for major inspections and the legal enforcement provisions needed, in order to avoid further transformations in the natural conditions of these systems.Nascentes são importantes elementos da paisagem pela sua relevância econômica, social e ecológica. Tendo em vista a crescente degradação desses ecossistemas, aliado ao pouco conhecimento sobre a sua biodiversidade em regiões tropicais, esta tese tem como objetivo geral ampliar o conhecimento sobre nascentes de regiões tropicais e prover um estudo sobre a diversidade e aspectos ecológicos de oligoquetas aquáticos nesse ecossistema. A fim de confirmar a carência de estudos em nascentes, especificamente sobre a fauna de oligoquetas, foi feito um levantamento bibliográfico sobre os estudos realizados em 30 anos (1985-2015) nos mais diversos ambientes aquáticos continentais em todo o mundo. A pesquisa mostrou que nascentes estão entre os ecossistemas menos estudados, juntamente com corpos d’água de cavernas e pântanos. Também realizamos coletas da fauna, medimos variáveis físicas e químicas e aplicamos um protocolo de avaliação rápida (PAR) em nascentes localizadas em diferentes municípios de Minas Gerais, tanto em Unidades de Conservação (UCs) quanto em áreas públicas e particulares. Os resultados mostraram que a composição de espécies de oligoquetas de nascentes que emergem de forma difusa formando uma área alagada (helocreno), é diferente daquela de nascentes que formam riachos (reocreno) e poças (limnocreno), provavelmente devido à sua maior heterogeneidade. Também verificamos que a diversidade beta foi alta nas três tipologias, indicando que os esforços para a conservação desses ecossistemas devem incluir um grande número de nascentes de todas as tipologias. Os resultados desse estudo também enfatizam, após a aplicação do PAR, que, apesar da maioria das nascentes serem classificadas como ótimas, nascentes localizadas em áreas urbanas foram classificadas como razoável ou ruim, mesmo estando algumas delas em UCs. Isso mostra a importância das UCs na preservação das nascentes, assim como sua vulnerabilidade quando inseridas em ambientes urbanos. Concluímos que este estudo sobre as nascentes contribui não apenas para o conhecimento do tema, mas também para a gestão ambiental, pois direciona para os habitats e locais que mais carecem de estudo, mostra a importância de se preservar diferentes tipos de nascentes para a manutenção da diversidade e aponta para a necessidade de maior fiscalização e cumprimento dos dispositivos legais, a fim de evitar maiores alterações nas condições naturais desses ambientes.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Inventário, riqueza e distribuição espacial de Oligochaeta (Annelida, Clitellata) em ambientes lóticos de Mata Atlântica (Minas Gerais, Brasil)

The present study aimed knows space richness and distribution of oligochaetes on first order streams situated on preserved areas. The dissertation is divided on two sections: the first one treats about a inventory containing information about ecology and geographic distribution of oligochaetes species indentified on eight streams located on State of Minas Gerais; the second one approach oligochaetes distribution in this streams, inserted on two vegetation types of Atlantic Forest ( Semidecidual Estacional Forest and Rupestres Fields); bring too an mesoscale approach through study of oligochaetes in riffles and pools mesohabitats. One hundred and sixty samples of litter was taken (eighty on riffles and eighty on pools), with Surber sampler, at the months of May, June, July and September of 2010 and June of 2011 on eight first order streams, situated on municipalities Juiz de Fora and Lima Duarte, State Minas Gerais. Twenty oligochaetes taxa was inventoried, of witch -Bratislavia (?) sp.- probably is a new specie, adding it up 4376 specimens. In terms of richness, the most representative genus was Pristina, with ten (10) species. Different areas vegetation types had the highest value of beta diversity index. As to mesohabitats, fauna don’t show separation between riffles and pools, indicating that factors related minor scale differences, like running speed, streams spread and depth, don’t affect on significative way on fauna distribution. The results obtained in this study came add to an important form to knowledge about distribution of oligochaetes species on Brazil, mainly on preserved lotic environments, sites with few studies performed.O presente trabalho objetivou conhecer a riqueza e distribuição espacial de oligoquetas em córregos de primeira ordem localizados em áreas preservadas. A dissertação está dividida em duas seções: a primeira trata de um inventário contendo informações sobre a distribuição geográfica e ecologia das espécies de oligoquetas identificadas em oito córregos localizados no Estado de Minas Gerais; a segunda aborda a distribuição espacial de oligoquetas nesses córregos, inseridos em duas fisionomias vegetais de Mata Atlântica (Floresta Estacional Semidecidual e Campos Rupestres); traz também uma abordagem em mesoescala através do estudo dos oligoquetas em mesohabitats de remanso e corredeira. Cento e sessenta amostras de folhiço submerso foram obtidas (oitenta em corredeiras e oitenta em remansos), com amostrador Surber, nos meses de maio, junho, julho e setembro de 2010 e junho de 2011 em oito córregos de primeira ordem, localizados nos municípios de Juiz de Fora e Lima Duarte, Estado de Minas Gerais. Foram inventariados 20 taxa de oligoquetas, dos quais um -Bratislavia (?) sp.- possivelmente é uma espécie nova, totalizando 4.376 espécimes. Em termos de riqueza, o gênero mais representativo foi Pristina, com 10 espécies. Foi encontrado maior valor do índice de diversidade beta entre áreas de fisionomias vegetais diferentes. Quanto aos mesohabitats, a fauna não mostrou separação entre corredeiras e remansos, indicando que fatores ligados às diferenças em menor escala, como velocidade da corrente, largura e profundidade do córrego, não interferiram de forma significativa na distribuição da fauna. Os resultados obtidos nesse estudo vêm contribuir de forma importante para o conhecimento sobre a distribuição das espécies de oligoquetas no Brasil, sobretudo em ambientes lóticos preservados, ambientes para os quais poucos estudos foram realizados.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Global panorama of studies about freshwater oligochaetes: main trends and gaps

Abstract Freshwater oligochaetes have been studied over the years in a wide range of habitats around the world. To analyse the data published about freshwater oligochaetes in the 31 year period between 1985 and 2015, we searched for documents in the ISI Web of Science, Scopus and SciELO databases. A total of 979 works were evaluated from 184 periodicals. The United States is the country with the most publications about aquatic oligochaetes, followed by France, Germany and Italy. Works related to the ecology and ecotoxicology of these organisms are most abundant. Studies carried out in the laboratory are most frequent, consisting of investigations involving bioassays, morphology, genetics and molecular biology. The results also show that spring, cave water bodies and swamps have been studied less than any other aquatic habitat and that countries of the Southern Hemisphere are under-represented in the studies of aquatic oligochaetes. Hence, there is a need for increased efforts to fill in gaps in the knowledge about these oligochaetes

Inventory and distribution of Oligochaeta (Annelida, Clitellata) in first-order streams in preserved areas of the state of Minas Gerais, Brazil

Data resulting from species inventories shed light on the richness and distribution of various groups. In Minas Gerais, work on inventory and distribution of the oligochaetes of lotic environments in preserved areas are non-existent. Therefore, this study aimed to inventory the limnic oligochaetes fauna of first-order streams located in four preserved areas, to expand knowledge of the ecology and distribution of this group. In total, 19 taxa were inventoried, belonging to the families Naididae and Enchytraeidae and the superorder Megadrili (earthworms), with the genus Pristina having the largest number of species. The number of species found in this investigation corresponds to 22% of oligochaetes species recorded in Brazilian aquatic environments. The results obtained add important knowledge of the distribution of some oligochaetes species in Brazil, represent the first records of species for the four preserved areas studied and confirm the first occurrence of various species in the state

Diversity and distribution of oligochaetes in tropical forested streams, southeastern Brazil

The distribution and beta diversity of oligochaete assemblages were investigated in different spatial scales to verify the influence of environmental factors and geographic distance on their structure. Two types of mesohabitats (riffles and pools) were sampled in eight first-order streams located in four preservation areas (Poço D’Anta Municipal Biological Reserve, Santa Cândida Municipal Biological Reserve, Ibitipoca State Park and a private farm called Fazenda Floresta) and two Atlantic Forest phytophysiognomies (Seasonal Semideciduous Forest and Rocky Field). Variations in the taxon richness, abundance and composition of the oligochaete assemblages occurred between streams and phytophysiognomies, but not between riffles and pools in the same stream. Low beta diversity values were found and both turnover and nestedness contributed similarly in the environments studied, which could have occurred because of the high capability of oligochaetes to adapt to different environmental conditions. Although the canonical correspondence analysis explained 85.5% of the data (first three axes), the partial Mantel test showed greater influence of geographic distance on the faunal composition than the environmental variables measured. Simple linear regression confirmed this result and showed that the decay of similarity increased with distance between streams. The information from this study sheds light on how environmental and spatial factors determine the variation in the distribution and diversity of oligochaetes in forested low-order streams.</p