Bio-ecological study of the water mites (Acari: Hydracarina) of the pond of El-Goureate in the National Park of El-Kala (North-East of Algeria)

This study aimed to present faunistic and ecological data on aquatic mites living in small permanent basins andselected lakes in the El-Kala National Park (Northeast of Algeria). Thus, this study shows the research of Hydracarina in the park comprehensively over the two years. We have identified the living Hydracarina species in the semi-temporary studysite at Goureate pond. The existence of an unknown and interesting Hydracarina fauna has been revealed. The collection of specimens revealed the presence of 9 species divided into 5 families. The identification required the study of ecological indices and the measurement of physicochemical parameters (temperature, humidity). The results of the univariate analysisof variance test fixed model, applied to each of the 9 physicochemical variables and a variable related to the number ofHydracarina, for two years. The results showed a very highly significant difference for water temperature and atmospheric temperature and a just significant difference for the number of Hydracarina, while no significant difference for pH, humidity, conductivity, NO-2, PO-4, NH+4 is registered, and the study of the abundance of the identified species in the four stations during the four seasons.(AU)

Bio-ecological study of the water mites (Acari: Hydracarina) of the pond of El-Goureate in the National Park of El-Kala (North-East of Algeria)

This study aimed to present faunistic and ecological data on aquatic mites living in small permanent basins andselected lakes in the El-Kala National Park (Northeast of Algeria). Thus, this study shows the research of Hydracarina in the park comprehensively over the two years. We have identified the living Hydracarina species in the semi-temporary studysite at Goureate pond. The existence of an unknown and interesting Hydracarina fauna has been revealed. The collection of specimens revealed the presence of 9 species divided into 5 families. The identification required the study of ecological indices and the measurement of physicochemical parameters (temperature, humidity). The results of the univariate analysisof variance test fixed model, applied to each of the 9 physicochemical variables and a variable related to the number ofHydracarina, for two years. The results showed a very highly significant difference for water temperature and atmospheric temperature and a just significant difference for the number of Hydracarina, while no significant difference for pH, humidity, conductivity, NO-2, PO-4, NH+4 is registered, and the study of the abundance of the identified species in the four stations during the four seasons.(AU)

Bio-ecological study of the water mites (Acari: Hydracarina) of the pond of El-Goureate in the National Park of El-Kala (North-East of Algeria)

This study aimed to present faunistic and ecological data on aquatic mites living in small permanent basins andselected lakes in the El-Kala National Park (Northeast of Algeria). Thus, this study shows the research of Hydracarina in the park comprehensively over the two years. We have identified the living Hydracarina species in the semi-temporary studysite at Goureate pond. The existence of an unknown and interesting Hydracarina fauna has been revealed. The collection of specimens revealed the presence of 9 species divided into 5 families. The identification required the study of ecological indices and the measurement of physicochemical parameters (temperature, humidity). The results of the univariate analysisof variance test fixed model, applied to each of the 9 physicochemical variables and a variable related to the number ofHydracarina, for two years. The results showed a very highly significant difference for water temperature and atmospheric temperature and a just significant difference for the number of Hydracarina, while no significant difference for pH, humidity, conductivity, NO-2, PO-4, NH+4 is registered, and the study of the abundance of the identified species in the four stations during the four seasons.

Benthic macroinvertebrates as bioindicators of water quality in an Atlantic forest fragment

The objective of this study was to evaluate benthic macroinvertebrate communities as bioindicators of water quality in five streams located in the "Reserva Particular do Patrimônio Natural" (RPPN) Mata Samuel de Paula and its surroundings, in the municipality of Nova Lima near the city of Belo Horizonte, Minas Gerais State, southeastern Brazil. This region has been strongly modified by human activities including mining and urbanization. Samples were collected in the field every three months between August 2004 and November 2005, totaling six samplings in the rainy and dry seasons. This assessment identified one area ecologically altered while the other sampling sites were found to be minimally disturbed systems, with well-preserved ecological conditions. However, according to the Biological Monitoring Work Party (BMWP) and the Average Score Per Taxon (ASPT) indices, all sampling sites had excellent water quality. A total of 14,952 organisms was collected, belonging to 155 taxa (148 Insecta, two Annelida, one Bivalvia, one Decapoda, one Planariidae, one Hydracarina, and one Entognatha). The most abundant benthic groups were Chironomidae (47.9%), Simuliidae (12.3%), Bivalvia (7.5%), Decapoda (6.1%), Oligochaeta (5.2%), Polycentropodidae (3.7%), Hydropsychidae (2.5%), Calamoceratidae (1.8%), Ceratopogonidae (1.7%), and Libellulidae (1.2%). The assessment of the benthic functional feeding groups showed that 34% of the macroinvertebrates were collector-gatherers, 29% predators, 24% collector-filterers, 8% shredders, and 5% scrapers. The RPPN Mata Samuel de Paula comprises diversified freshwater habitats that are of great importance for the conservation of many benthic taxa that are intolerant to organic pollution.

O objetivo deste estudo foi avaliar as comunidades de macroinvertebrados bentônicos como bioindicadoras de qualidade de água em cinco riachos localizados na Reserva Particular do Patrimônio Natural (RPPN) Mata Samuel de Paula, no município de Nova Lima, próximo à cidade de Belo Horizonte, estado de Minas Gerais, sudeste do Brasil. A região tem sido severamente alterada por atividades antrópicas incluindo mineração e urbanização. As amostras foram coletadas em campo trimestralmente entre agosto de 2004 e novembro de 2005, totalizando 6 campanhas nas estações seca e chuvosa. Este estudo identificou um riacho como alterado ecologicamente enquanto os demais foram caracterizados como minimamente alterados, com condições ecológicas bem preservadas. No entanto, de acordo com os índices Biological Monitoring Work Party (BMWP) e Average Score Per Taxon (ASPT), todos os riachos possuem qualidade de água excelente. No total, 14.952 organismos foram coletados, pertencendo a 155 táxons (148 Insecta, 2 Annelida, 1 Bivalvia, 1 Decapoda, 1 Planariidae, 1 Hydracarina e 1 Entognatha). Os grupos bentônicos mais abundantes foram Chironomidae (47,9%), Simuliidae (12,3%), Bivalvia (7,5%), Decapoda (6,1%), Oligochaeta (5,2%), Polycentropodidae (3,7%), Hydropsychidae (2,5%), Calamoceratidae (1,8%), Ceratopogonidae (1,7%) e Libellulidae (1,2%). A classificação dos grupos tróficos funcionais evidenciou que 34% dos macroinvertebrados eram coletores-catadores, 29% predadores, 24% coletores-filtradores, 8% fragmentadores e 5% raspadores. A RPPN Mata Samuel de Paula protege hábitats aquáticos diversificados de grande importância para a conservação de muitos táxons de macroinvertebrados bentônicos que são intolerants à poluição.

Benthic macroinvertebrates as bioindicators of water quality in an Atlantic forest fragment

The objective of this study was to evaluate benthic macroinvertebrate communities as bioindicators of water quality in five streams located in the "Reserva Particular do Patrimônio Natural" (RPPN) Mata Samuel de Paula and its surroundings, in the municipality of Nova Lima near the city of Belo Horizonte, Minas Gerais State, southeastern Brazil. This region has been strongly modified by human activities including mining and urbanization. Samples were collected in the field every three months between August 2004 and November 2005, totaling six samplings in the rainy and dry seasons. This assessment identified one area ecologically altered while the other sampling sites were found to be minimally disturbed systems, with well-preserved ecological conditions. However, according to the Biological Monitoring Work Party (BMWP) and the Average Score Per Taxon (ASPT) indices, all sampling sites had excellent water quality. A total of 14,952 organisms was collected, belonging to 155 taxa (148 Insecta, two Annelida, one Bivalvia, one Decapoda, one Planariidae, one Hydracarina, and one Entognatha). The most abundant benthic groups were Chironomidae (47.9%), Simuliidae (12.3%), Bivalvia (7.5%), Decapoda (6.1%), Oligochaeta (5.2%), Polycentropodidae (3.7%), Hydropsychidae (2.5%), Calamoceratidae (1.8%), Ceratopogonidae (1.7%), and Libellulidae (1.2%). The assessment of the benthic functional feeding groups showed that 34% of the macroinvertebrates were collector-gatherers, 29% predators, 24% collector-filterers, 8% shredders, and 5% scrapers. The RPPN Mata Samuel de Paula comprises diversified freshwater habitats that are of great importance for the conservation of many benthic taxa that are intolerant to organic pollution.

O objetivo deste estudo foi avaliar as comunidades de macroinvertebrados bentônicos como bioindicadoras de qualidade de água em cinco riachos localizados na Reserva Particular do Patrimônio Natural (RPPN) Mata Samuel de Paula, no município de Nova Lima, próximo à cidade de Belo Horizonte, estado de Minas Gerais, sudeste do Brasil. A região tem sido severamente alterada por atividades antrópicas incluindo mineração e urbanização. As amostras foram coletadas em campo trimestralmente entre agosto de 2004 e novembro de 2005, totalizando 6 campanhas nas estações seca e chuvosa. Este estudo identificou um riacho como alterado ecologicamente enquanto os demais foram caracterizados como minimamente alterados, com condições ecológicas bem preservadas. No entanto, de acordo com os índices Biological Monitoring Work Party (BMWP) e Average Score Per Taxon (ASPT), todos os riachos possuem qualidade de água excelente. No total, 14.952 organismos foram coletados, pertencendo a 155 táxons (148 Insecta, 2 Annelida, 1 Bivalvia, 1 Decapoda, 1 Planariidae, 1 Hydracarina e 1 Entognatha). Os grupos bentônicos mais abundantes foram Chironomidae (47,9%), Simuliidae (12,3%), Bivalvia (7,5%), Decapoda (6,1%), Oligochaeta (5,2%), Polycentropodidae (3,7%), Hydropsychidae (2,5%), Calamoceratidae (1,8%), Ceratopogonidae (1,7%) e Libellulidae (1,2%). A classificação dos grupos tróficos funcionais evidenciou que 34% dos macroinvertebrados eram coletores-catadores, 29% predadores, 24% coletores-filtradores, 8% fragmentadores e 5% raspadores. A RPPN Mata Samuel de Paula protege hábitats aquáticos diversificados de grande importância para a conservação de muitos táxons de macroinvertebrados bentônicos que são intolerants à poluição.

Water mite predation on zooplankton of a tropical lake

Water mite (Krendowskia sp.) predation on zooplanktonic species from Lake Monte Alegre (São Paulo State, Brazil) was tested in laboratory experiments. One cladoceran, Daphnia gessneri, two copepods, Tropocyclops prasinus and Thermocyclops decipiens, and Chaoborus larvae III and IV were supplied as prey to adult mites. The cladoceran Ceriodaphnia cornuta was used in the experiment with mite nymphs. Only D.gessneri was preyed on by mites, at an average rate of 7 ind./mite/day, at 23-24ºC. Although Chaoborus was not eaten by the predator in the experiment, in direct observations older larvae were seen to be seized by several mites, both predators and prey sinking to the bottom of the vessel. Adult Daphnia was grabbed by its dorsal side, swimming together with the mite. There was an increase in predatory activity two hours after sunset.

A predação do zooplâncton por ácaros aquáticos (Krendowskia sp.) do Lago Monte Alegre (Estado de São Paulo, Brasil) foi testada em experimentos de laboratório. Um cladócero, Daphnia gessneri, dois copépodos, Tropocyclops prasinus e Thermocyclops decipiens e larvas III e IV de Chaoborus foram oferecidos como presas a ácaros adultos. O cladócero Ceriodaphnia cornuta foi usado em experimentos com ninfas de ácaros. Apenas D. gessneri foi predada pelos ácaros, a uma taxa média de 7 ind./ácaro/dia, a 23-24ºC. Embora Chaoborus não tenha sido comido pelo predador no experimento, nas observações diretas, grupos de ácaros foram vistos agarrados a larvas III e IV. Ao agarrarem os caoborídeos, os ácaros paravam de nadar e afundavam com a presa. Ainda nas observações diretas, os ácaros foram vistos agarrados ao dorso de Daphnia adultas e, nesta ocasião, continuavam nadando com a presa. Foi observado aumento na atividade predatória duas horas após o pôr-do-sol.

Water mite predation on zooplankton of a tropical lake

Water mite (Krendowskia sp.) predation on zooplanktonic species from Lake Monte Alegre (São Paulo State, Brazil) was tested in laboratory experiments. One cladoceran, Daphnia gessneri, two copepods, Tropocyclops prasinus and Thermocyclops decipiens, and Chaoborus larvae III and IV were supplied as prey to adult mites. The cladoceran Ceriodaphnia cornuta was used in the experiment with mite nymphs. Only D.gessneri was preyed on by mites, at an average rate of 7 ind./mite/day, at 23-24ºC. Although Chaoborus was not eaten by the predator in the experiment, in direct observations older larvae were seen to be seized by several mites, both predators and prey sinking to the bottom of the vessel. Adult Daphnia was grabbed by its dorsal side, swimming together with the mite. There was an increase in predatory activity two hours after sunset.

A predação do zooplâncton por ácaros aquáticos (Krendowskia sp.) do Lago Monte Alegre (Estado de São Paulo, Brasil) foi testada em experimentos de laboratório. Um cladócero, Daphnia gessneri, dois copépodos, Tropocyclops prasinus e Thermocyclops decipiens e larvas III e IV de Chaoborus foram oferecidos como presas a ácaros adultos. O cladócero Ceriodaphnia cornuta foi usado em experimentos com ninfas de ácaros. Apenas D. gessneri foi predada pelos ácaros, a uma taxa média de 7 ind./ácaro/dia, a 23-24ºC. Embora Chaoborus não tenha sido comido pelo predador no experimento, nas observações diretas, grupos de ácaros foram vistos agarrados a larvas III e IV. Ao agarrarem os caoborídeos, os ácaros paravam de nadar e afundavam com a presa. Ainda nas observações diretas, os ácaros foram vistos agarrados ao dorso de Daphnia adultas e, nesta ocasião, continuavam nadando com a presa. Foi observado aumento na atividade predatória duas horas após o pôr-do-sol.