Cassiano Marchett | Universidade de Caxias do Sul (original) (raw)

Papers by Cassiano Marchett

Research paper thumbnail of New records of Maned Wolf, Chrysocyon brachyurus (Illiger, 1815), in Rio Grande do Sul, Brazil: consequences for conservation

Research paper thumbnail of Caracterização morfológica das lagoas de Osório, norte da planície costeira do Rio Grande do Sul, Brasil

A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, impre... more A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, imprescindivelmente, a morfologia do corpo de agua. O conhecimento cientifico dos parâmetros morfometricos e fundamental nao somente para medidas e quantificacoes, mas tambem para o entendimento dos processos internos que influenciam a dinâmica dos nutrientes e a distribuicao das comunidades biologicas. A planicie costeira do Rio Grande do Sul foi formada por processos de erosao e deposicao durante eventos marinhos de transgressao e regressao, associados a erosao fluvial e eolica durante o Quaternario. Durante o Pleistoceno e Holoceno foram estruturados quatro sistemas de deposito, chamados laguna-barreira, compreendendo grande diversidade de ecossistemas umidos, dentre os quais as lagoas ao longo da costa do Oceano Atlântico, em sua maioria contendo agua doce. Devido a sua genese, essas lagoas sao rasas, com profundidade relativa inferior a 2% e alcancam profundidade maxima de 11 metros no litoral medio do Rio Grande do Sul. O presente estudo teve como objetivo caracterizar morfologicamente as lagoas do municipio de Osorio, Rio Grande do Sul, Brasil. Devido as caracteristicas regionais de toponimia e segmentacao, algumas lagoas puderam ser avaliadas como um ou mais corpos de agua, resultando na caracterizacao de 20 corpos de agua a partir dos 16 nomes oficiais atribuidos as lagoas. Os levantamentos batimetricos foram realizados entre os anos de 2013 e 2015, com o uso de ecobatimetro acoplado de GPS e aplicacao de sensoriamento remoto e Sistemas de Informacoes Geograficas (SIG). Como resultados foram produzidos um artigo submetido a Revista Brasileira de Recursos Hidricos e um capitulo de livro na obra Atlas Sociombiental do Municipio de Osorio. No artigo intitulado “Morphological characterization of thirteen lakes in Osorio, northern coastal plain of Rio Grande do Sul, Brazil” foram caracterizadas morfologicamente 13 lagoas no municipio de Osorio, Rio Grande do Sul, Brasil. A analise de Cluster distinguiu quatro grupos morfologicos, confirmados pela Analise Discriminante. A analise de componentes principais identificou o primeiro componente com carga positiva para parâmetros de tamanho e carga negativa para a profundidade relativa, enquanto o segundo componente apresentou carga positiva para as profundidades maxima e profundidade media e carga negativa para o desenvolvimento do perimetro e o desenvolvimento do volume. Os parâmetros de tamanho mostraram ser, portanto, mais importantes na classificacao das lagoas do que os parâmetros de profundidade. A baixa profundidade das lagoas estudadas (profundidade maxima = 4,6 m, maior profundidade media = 2,2 m) e elemento fundamental na gestao dos recursos hidricos, uma vez que o pequeno volume e tamanho tornam as lagoas rasas mais suscetiveis a processos de eutrofizacao. No capitulo intitulado “Morfologia”, as lagoas sao apresentadas com mapa batimetrico, imagem aerea, parâmetros morfometricos e descricao das principais caracteristicas de cada lagoa. O capitulo e apresentado de forma didatica e com linguagem acessivel, de forma a abranger um publico amplo. Dados morfologicos sao essenciais para a compreensao ecologica das lagoas, especialmente se associados a analises de transparencia, turbidez, distribuicao vertical de nutrientes e oxigenio e aplicacao de indices troficos, bem como sao subsidio para a gestao dos recursos hidricos.

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, Rio Grande do Sul

Research paper thumbnail of Caracterização morfológica das lagoas de Osório, norte da planície costeira do Rio Grande do Sul, Brasil

A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, impre... more A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, imprescindivelmente, a morfologia do corpo de agua. O conhecimento cientifico dos parâmetros morfometricos e fundamental nao somente para medidas e quantificacoes, mas tambem para o entendimento dos processos internos que influenciam a dinâmica dos nutrientes e a distribuicao das comunidades biologicas. A planicie costeira do Rio Grande do Sul foi formada por processos de erosao e deposicao durante eventos marinhos de transgressao e regressao, associados a erosao fluvial e eolica durante o Quaternario. Durante o Pleistoceno e Holoceno foram estruturados quatro sistemas de deposito, chamados laguna-barreira, compreendendo grande diversidade de ecossistemas umidos, dentre os quais as lagoas ao longo da costa do Oceano Atlântico, em sua maioria contendo agua doce. Devido a sua genese, essas lagoas sao rasas, com profundidade relativa inferior a 2% e alcancam profundidade maxima de 11 metros no l...

Research paper thumbnail of Avaliação in vitro de extratos vegetais para o controle de fungos patogênicos de flores

Revista Brasileira De Agroecologia, Aug 31, 2011

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, RS

Research paper thumbnail of Volume de água e tendência de eutrofização das Lagoas Costeiras

Research paper thumbnail of Gestão dos Recursos Hídricos - Municípios de Cidreira, Balneário Pinhal e Palmares do Sul

Research paper thumbnail of Métodos de geoprocessamento como auxílio na geração de um Atlas Sócio-Ambiental de quatro municípios litorâneos do Rio Grande do Sul

The coastal plain of Rio Grande do Sul is characterized by a chain of shallow freshwater lakes, c... more The coastal plain of Rio Grande do Sul is characterized by a chain of shallow freshwater lakes, consisting in an unique ecological complex. The lake system is the main source for multiple uses in this region, mainly for irrigation. The lack of knowledge and planning may conduct to inappropriate practices that compromise the sustainability of water resources in this region.

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, Rio Grande do Sul

The ''Campos de Cima da Serra'' grasslands present a rare situation in the world ... more The ''Campos de Cima da Serra'' grasslands present a rare situation in the world in terms of association of Araucaria forest and natural grasslands. Spatial and temporal distribution of the lands are important factors that contribute to understanding the existence of current grasslands in southern Brazil. In spite the enormous associated biodiversity, the protection of the grasslands has been neglected. This study has the aim to examine the land use and the changes between the years 1986 and 2009, with emphasis on the distribution of grassland and their spatial dynamics in the district of Criuva, Caxias do Sul, Rio Grande do Sul, Brazil, using remote sensing techniques. Landsat TM5 images from 1986 and 2009 were used and processed in ENVI ® 4.6.1. Visits to the study area were done to define the land use types and photo documentation. The knowledge of the area, the satellite images and the NDVI were used for the samples selection for the supervised classification wit...

Research paper thumbnail of AVALIAÇÃO DO POTENCIAL ANTAGÔNICO DO FUNGO Tremella sp. FRENTE A DIFERENTES FITOPATÓGENOS DA MACIEIRA

Revista Brasileira De Agroecologia, May 1, 2007

RESUMO O controle microbiológico de fitopatógenos é uma alternativa na agricultura, quando o obje... more RESUMO O controle microbiológico de fitopatógenos é uma alternativa na agricultura, quando o objetivo é, além de diminuir o índices de doenças, a diminuição do uso de agroquímicos. Com esta proposta foi avaliado in vitro o potencial antagônico do fungo epifítico da macieira (Malus domestica), Tremella spp. isolado da microbiota do sistema de produção orgânico da macieira. Os fungos fitopatogênicos desafiados foram Botryosphaeria spp., Pezicula spp., Colletotrichum spp., Fusarium spp. e Alternaria spp., agentes causais de várias doenças de importância econômica na cultura da maçã.

Research paper thumbnail of Impactos ambientais do turismo em lagoas costeiras do Rio Grande do Sul

Caderno Virtual De Turismo, Apr 29, 2013

Research paper thumbnail of Levantamento do uso e cobertura do solo no município de Tavares, RS

Research paper thumbnail of Gestão dos Recursos Hídricos - Municípios de Cidreira, Balneário Pinhal e Palmares do Sul

Research paper thumbnail of Volume de água e tendência de eutrofização das Lagoas Costeiras

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Acta Limnologica Brasiliensia, 2014

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.

Research paper thumbnail of Do different landscapes influence the response of native and non-native bee species in the Eucalyptus pollen foraging, in southern Brazil?

Forest Ecology and Management, 2014

Eucalyptus is an exotic genus in Brazil with massive flowerings that are visited by bees in searc... more Eucalyptus is an exotic genus in Brazil with massive flowerings that are visited by bees in search of food. To verify the use of Eucalyptus spp. in the pollinic diet of Apis mellifera L. and Melipona obscurior Moure, we evaluated the proportion of pollen that both bee species collected from Eucalyptus spp. in relation to the relative abundance of Eucalyptus spp. in the study areas. The study occurred in the localities of Riozinho and Rolante, RS, Brazil, whose land cover was characterized by remote sensing. Every two weeks from April/2009 to March/2010, pollen was collected from foragers of three hives of each bee species for posterior palynological analysis. The median percentage of Eucalyptus spp. pollen collected in Riozinho was 16.3% (0-55.3%; n = 18) for A. mellifera and 2.6% (0-72.3%; n = 15) for M. obscurior. In Rolante, the median was 21.9% (0-66.7%; n = 19) for A. mellifera and 17.6% (0-82.9%; n = 17) for M. obscurior. The difference between these values was significant only when considered the collection period. The index of use was similar for both species and both areas. The attractiveness and availability of flowering Eucalyptus spp. throughout the year allowed both species of bees to use pollen from this genus in both areas, regardless of the landscape characteristics. In southern Brazil, sustainable practices for the management of eucalypts can contribute to the survival of social bees during the periods of lower pollen production by other sources.

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Acta Limnologica Brasiliensia, 2014

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.

Research paper thumbnail of New records of Maned Wolf, Chrysocyon brachyurus (Illiger, 1815), in Rio Grande do Sul, Brazil: consequences for conservation

Research paper thumbnail of Caracterização morfológica das lagoas de Osório, norte da planície costeira do Rio Grande do Sul, Brasil

A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, impre... more A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, imprescindivelmente, a morfologia do corpo de agua. O conhecimento cientifico dos parâmetros morfometricos e fundamental nao somente para medidas e quantificacoes, mas tambem para o entendimento dos processos internos que influenciam a dinâmica dos nutrientes e a distribuicao das comunidades biologicas. A planicie costeira do Rio Grande do Sul foi formada por processos de erosao e deposicao durante eventos marinhos de transgressao e regressao, associados a erosao fluvial e eolica durante o Quaternario. Durante o Pleistoceno e Holoceno foram estruturados quatro sistemas de deposito, chamados laguna-barreira, compreendendo grande diversidade de ecossistemas umidos, dentre os quais as lagoas ao longo da costa do Oceano Atlântico, em sua maioria contendo agua doce. Devido a sua genese, essas lagoas sao rasas, com profundidade relativa inferior a 2% e alcancam profundidade maxima de 11 metros no litoral medio do Rio Grande do Sul. O presente estudo teve como objetivo caracterizar morfologicamente as lagoas do municipio de Osorio, Rio Grande do Sul, Brasil. Devido as caracteristicas regionais de toponimia e segmentacao, algumas lagoas puderam ser avaliadas como um ou mais corpos de agua, resultando na caracterizacao de 20 corpos de agua a partir dos 16 nomes oficiais atribuidos as lagoas. Os levantamentos batimetricos foram realizados entre os anos de 2013 e 2015, com o uso de ecobatimetro acoplado de GPS e aplicacao de sensoriamento remoto e Sistemas de Informacoes Geograficas (SIG). Como resultados foram produzidos um artigo submetido a Revista Brasileira de Recursos Hidricos e um capitulo de livro na obra Atlas Sociombiental do Municipio de Osorio. No artigo intitulado “Morphological characterization of thirteen lakes in Osorio, northern coastal plain of Rio Grande do Sul, Brazil” foram caracterizadas morfologicamente 13 lagoas no municipio de Osorio, Rio Grande do Sul, Brasil. A analise de Cluster distinguiu quatro grupos morfologicos, confirmados pela Analise Discriminante. A analise de componentes principais identificou o primeiro componente com carga positiva para parâmetros de tamanho e carga negativa para a profundidade relativa, enquanto o segundo componente apresentou carga positiva para as profundidades maxima e profundidade media e carga negativa para o desenvolvimento do perimetro e o desenvolvimento do volume. Os parâmetros de tamanho mostraram ser, portanto, mais importantes na classificacao das lagoas do que os parâmetros de profundidade. A baixa profundidade das lagoas estudadas (profundidade maxima = 4,6 m, maior profundidade media = 2,2 m) e elemento fundamental na gestao dos recursos hidricos, uma vez que o pequeno volume e tamanho tornam as lagoas rasas mais suscetiveis a processos de eutrofizacao. No capitulo intitulado “Morfologia”, as lagoas sao apresentadas com mapa batimetrico, imagem aerea, parâmetros morfometricos e descricao das principais caracteristicas de cada lagoa. O capitulo e apresentado de forma didatica e com linguagem acessivel, de forma a abranger um publico amplo. Dados morfologicos sao essenciais para a compreensao ecologica das lagoas, especialmente se associados a analises de transparencia, turbidez, distribuicao vertical de nutrientes e oxigenio e aplicacao de indices troficos, bem como sao subsidio para a gestao dos recursos hidricos.

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, Rio Grande do Sul

Research paper thumbnail of Caracterização morfológica das lagoas de Osório, norte da planície costeira do Rio Grande do Sul, Brasil

A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, impre... more A compreensao da dinâmica hidrica e das relacoes ecologicas em estudos limnologicos inclui, imprescindivelmente, a morfologia do corpo de agua. O conhecimento cientifico dos parâmetros morfometricos e fundamental nao somente para medidas e quantificacoes, mas tambem para o entendimento dos processos internos que influenciam a dinâmica dos nutrientes e a distribuicao das comunidades biologicas. A planicie costeira do Rio Grande do Sul foi formada por processos de erosao e deposicao durante eventos marinhos de transgressao e regressao, associados a erosao fluvial e eolica durante o Quaternario. Durante o Pleistoceno e Holoceno foram estruturados quatro sistemas de deposito, chamados laguna-barreira, compreendendo grande diversidade de ecossistemas umidos, dentre os quais as lagoas ao longo da costa do Oceano Atlântico, em sua maioria contendo agua doce. Devido a sua genese, essas lagoas sao rasas, com profundidade relativa inferior a 2% e alcancam profundidade maxima de 11 metros no l...

Research paper thumbnail of Avaliação in vitro de extratos vegetais para o controle de fungos patogênicos de flores

Revista Brasileira De Agroecologia, Aug 31, 2011

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, RS

Research paper thumbnail of Volume de água e tendência de eutrofização das Lagoas Costeiras

Research paper thumbnail of Gestão dos Recursos Hídricos - Municípios de Cidreira, Balneário Pinhal e Palmares do Sul

Research paper thumbnail of Métodos de geoprocessamento como auxílio na geração de um Atlas Sócio-Ambiental de quatro municípios litorâneos do Rio Grande do Sul

The coastal plain of Rio Grande do Sul is characterized by a chain of shallow freshwater lakes, c... more The coastal plain of Rio Grande do Sul is characterized by a chain of shallow freshwater lakes, consisting in an unique ecological complex. The lake system is the main source for multiple uses in this region, mainly for irrigation. The lack of knowledge and planning may conduct to inappropriate practices that compromise the sustainability of water resources in this region.

Research paper thumbnail of Análise multitemporal do uso e cobertura da terra no distrito de Criúva, Caxias do Sul, Rio Grande do Sul

The ''Campos de Cima da Serra'' grasslands present a rare situation in the world ... more The ''Campos de Cima da Serra'' grasslands present a rare situation in the world in terms of association of Araucaria forest and natural grasslands. Spatial and temporal distribution of the lands are important factors that contribute to understanding the existence of current grasslands in southern Brazil. In spite the enormous associated biodiversity, the protection of the grasslands has been neglected. This study has the aim to examine the land use and the changes between the years 1986 and 2009, with emphasis on the distribution of grassland and their spatial dynamics in the district of Criuva, Caxias do Sul, Rio Grande do Sul, Brazil, using remote sensing techniques. Landsat TM5 images from 1986 and 2009 were used and processed in ENVI ® 4.6.1. Visits to the study area were done to define the land use types and photo documentation. The knowledge of the area, the satellite images and the NDVI were used for the samples selection for the supervised classification wit...

Research paper thumbnail of AVALIAÇÃO DO POTENCIAL ANTAGÔNICO DO FUNGO Tremella sp. FRENTE A DIFERENTES FITOPATÓGENOS DA MACIEIRA

Revista Brasileira De Agroecologia, May 1, 2007

RESUMO O controle microbiológico de fitopatógenos é uma alternativa na agricultura, quando o obje... more RESUMO O controle microbiológico de fitopatógenos é uma alternativa na agricultura, quando o objetivo é, além de diminuir o índices de doenças, a diminuição do uso de agroquímicos. Com esta proposta foi avaliado in vitro o potencial antagônico do fungo epifítico da macieira (Malus domestica), Tremella spp. isolado da microbiota do sistema de produção orgânico da macieira. Os fungos fitopatogênicos desafiados foram Botryosphaeria spp., Pezicula spp., Colletotrichum spp., Fusarium spp. e Alternaria spp., agentes causais de várias doenças de importância econômica na cultura da maçã.

Research paper thumbnail of Impactos ambientais do turismo em lagoas costeiras do Rio Grande do Sul

Caderno Virtual De Turismo, Apr 29, 2013

Research paper thumbnail of Levantamento do uso e cobertura do solo no município de Tavares, RS

Research paper thumbnail of Gestão dos Recursos Hídricos - Municípios de Cidreira, Balneário Pinhal e Palmares do Sul

Research paper thumbnail of Volume de água e tendência de eutrofização das Lagoas Costeiras

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Acta Limnologica Brasiliensia, 2014

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.

Research paper thumbnail of Do different landscapes influence the response of native and non-native bee species in the Eucalyptus pollen foraging, in southern Brazil?

Forest Ecology and Management, 2014

Eucalyptus is an exotic genus in Brazil with massive flowerings that are visited by bees in searc... more Eucalyptus is an exotic genus in Brazil with massive flowerings that are visited by bees in search of food. To verify the use of Eucalyptus spp. in the pollinic diet of Apis mellifera L. and Melipona obscurior Moure, we evaluated the proportion of pollen that both bee species collected from Eucalyptus spp. in relation to the relative abundance of Eucalyptus spp. in the study areas. The study occurred in the localities of Riozinho and Rolante, RS, Brazil, whose land cover was characterized by remote sensing. Every two weeks from April/2009 to March/2010, pollen was collected from foragers of three hives of each bee species for posterior palynological analysis. The median percentage of Eucalyptus spp. pollen collected in Riozinho was 16.3% (0-55.3%; n = 18) for A. mellifera and 2.6% (0-72.3%; n = 15) for M. obscurior. In Rolante, the median was 21.9% (0-66.7%; n = 19) for A. mellifera and 17.6% (0-82.9%; n = 17) for M. obscurior. The difference between these values was significant only when considered the collection period. The index of use was similar for both species and both areas. The attractiveness and availability of flowering Eucalyptus spp. throughout the year allowed both species of bees to use pollen from this genus in both areas, regardless of the landscape characteristics. In southern Brazil, sustainable practices for the management of eucalypts can contribute to the survival of social bees during the periods of lower pollen production by other sources.

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Acta Limnologica Brasiliensia, 2014

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.

Research paper thumbnail of Morphological characterization of eighteen lakes of the north and middle coast of Rio Grande do Sul, Brazil

Aims: The present study aimed at a morphological characterization of 18 lakes of the municipaliti... more Aims: The present study aimed at a morphological characterization of 18 lakes of the municipalities of Cidreira, Balneário Pinhal and Palmares do Sul, situated in the northern and middle coastal plain of Rio Grande do Sul, Brazil. Methods: The morphometric survey was conducted in the summer of 2011/2012, based on echo sounder coupled with GPS and the application of remote sensing and GIS procedures. The morphometric parameters used for the characterization were: surface area, perimeter, perimeter development, volume, relative fetch, maximum depth, average depth, relative depth, median depth of volume, length and width. The statistical interpretation included Test of Normality, Coefficient of Variation, Correlation and Regression Analysis, Cluster Analysis, Discriminant Analysis and Principal Component Analysis. Results: Eighteen lakes were described and five of them are presented by aerial photo and bathymetric map. They represent the proposed morphological lake types. The calculation of the coefficient of variation revealed larger amplitudes of parameters related to lake size than to depth. The application and interpretation of cluster analysis, confirmed by discriminant analysis, distinguished those lakes in five morphological groups, which differ mainly by size and subsequently by depth. The Principal Component Analysis identified the first component with positively charged variables of size and negatively charged relative depth, and a second component with positive charge of maximum and average depths. Conclusions: The low relative depths and the exposure to constant northeastern winds reduce the transparency of the lakes. Consequently, they are light limited by suspension of inorganic and organic matter. A property that limits the application of trophic state indices. The high dynamic of the water bodies produces an oxygenated sediment surface that facilitates the settlement by aerobic organisms all over the bottom area. The shallowness and the low median depths of volume are limiting factors for sustainable water supply management. The morphological characteristics of the coastal lakes make very difficult an accurate ecological assessment based on usual trophic state criterions and a sustainable water resource management using general guidelines.