Acessibilidade / Reportar erro

Limnoperna fortunei Dunker, 1857 larvae in different environments of a Neotropical floodplain: relationships of abiotic variables and phytoplankton with different stages of development

Larvas de Limnoperna fortunei Dunker, 1857 em diferentes ambientes de uma planície de inundação Neotropical: relação com variáveis abióticas e algas fitoplanctônicas em diferentes estágios de desenvolvimento

Abstract

Limnoperna fortunei Dunker, 1857 is an Asian invasive freshwater bivalve. Although there need to contain their spread, studies about the biology of the larvae are scarce. We correlated the larval stages of L. fortunei with biotic factors such as phytoplankton and main abiotic variables in lotic environments of the Upper Paraná River floodplain. The four samples were taken quarterly during the year 2012. The Principal component analysis (PCA) showed only spatial differences, as did a Canonical Correspondence Analysis (CCA). High densities of larvae were recorded in all samples the Paraná River and Baía River only in December, especially those in their initial stage. In the biovolume of Class of algae, Bacillarophyceae showed the highest value, but Chlorophycea who was strongly correlated with the density of D-stage larvae. The large variety of phytoplankton, especially microplankton Chlorophyceae, high values of PO4, NH4 and temperature were positively correlated with high densities of D-stage larvae. We conclude that high temperature, and food availability, indicated by phytoplankton community, favored the reproduction of L. fortunei and enhance the ability of specie dispersion due to the increase in the emission of propagules. Therefore, studies that address the biology of golden mussel larvae should be performed in order to prevent its spread.

Keywords:
invasive species; limnic bivalves; Paraná river; dispersal patterns; environmental filters

Resumo

Limnoperna fortunei Dunker, 1857 é um bivalve asiático dulcícola invasor. Embora haja necessidade de conter sua dispersão, estudos que abordam a biologia de suas larvas ainda são escassos. Analisou-se as fases larvais de L. fortunei relacionando-as a fatores bióticos como a comunidade fitoplânctônica e às principais variáveis abióticas, em ambientes lóticos da planície de inundação do alto do rio Paraná. As quatro coletas foram trimestrais durante o ano de 2012. A análise de componentes principais (PCA) demonstrou apenas diferenças espaciais, assim como a Análise de Correspondência Canônica (CCA). Altas densidades de larvas foram registradas em todas as coletas no rio Paraná e no rio Baía apenas no mês de dezembro, principalmente para as larvas em estádio inicial. No biovolume das classes de algas, Bacillarophyceae obteve o maior valor, porém Chlorophycea foi a que fortemente correlacionou-se com a densidade de larvas D. A grande variedade de fitoplâncton, em especial de Chlorophyceae microplanctônica, altos valores de PO4, NH4 e temperatura estiveram positivamente correlacionadas com altas densidades de larvas D. Conclui-se que, altas temperaturas, e disponibilidade de alimento, como a comunidade fitoplanctônica, favorecem a reprodução de L. fortunei e aumentam a capacidade de dispersão da espécie devido ao incremento na emissão de propágulos. Portanto, estudos que abordem a biologia das larvas de mexilhão-dourado devem ser realizados a fim de evitar sua propagação.

Palavras-chave:
espécie invasora; bivalves límnicos; rio Paraná; padrão de dispersão; filtros ambientais

1 Introduction

Floodplains like the Upper Paraná River, are characterized by high heterogeneity of habitats (Ward et al., 2002WARD, J.V., TOCKNER, K., ARSCOTT, D.B. and CLARET, C., 2002. Riverine landscape diversity. Freshwater Biology, vol. 47, no. 4, pp. 517-539. http://dx.doi.org/10.1046/j.1365-2427.2002.00893.x.
http://dx.doi.org/10.1046/j.1365-2427.20...
; Ribeiro et al., 2012RIBEIRO, M.L., BLANCKAERT, K., ROY, A.G. and SCHLEISS, A.G., 2012. Hydromorphological implications of local tributary widening for river rehabilitation. Water Resources Research, vol. 48, no. 10, pp. 1-19.) and consequently high species diversity. Inspite of high levels of biodiversity, reservoir cascades located upstream of Upper Paraná River floodplain (Souza Filho and Stevaux, 1997SOUZA FILHO, E.E. and STEVAUX, J.C., 1997. Geologia e geomorfologia do complexo rio Baia, Curutuba, Ivinheima. In: A.E.A.M. VAZZPLER, A.A. AGOSTINHO and N.S.A. HAHN. A planície de inundação do alto rio Paraná: aspectos físicos, biológicos e socioeconômicos. Maringá: Editora da Universidade Estadual de Maringá, pp. 3-46.) have caused several changes in the hydrological regime and the physical and chemical water parameters (Agostinho et al., 2013AGOSTINHO, A.A., GOMES, L.C., BONECKER, C.C. and THOMAZ, S.M., 2013. Padrões de variação de longo prazo na planície de inundação do Alto do Rio Paraná. In: M. TABARELLI, C.F.D. ROCHA, P. ROMANOWSKI, O. ROCHA and L.D. LACERDA. PELD-CNPq: dez anos do programa de Pesquisas Ecológicas de Longa Duração: achados, lições e perspectivas. Recife: UFPE, pp. 165-196.). Such changes have strongly affected the aquatic communities (Barletta et al., 2010BARLETTA, M., JAUREGUIZAR, A.J., BAIGUN, C., FONTOURA, N.F., AGOSTINHO, A.A., ALMEIDA-VAL, V.M.F., VAL, A.L., TORRES, R.A., JIMENES-SEGURA, L.F., GIARRIZZO, T., FABRÉ, N.N., BATISTA, V.S., LASSO, C., TAPHORN, D.C., COSTA, M.F., CHAVES, P.T., VIEIRA, J.P. and CORRÊA, M.F.M., 2010. Fish and aquatic habitat conservation in South America: a continental overview with emphasis on neotropical systems. Journal of Fish Biology, vol. 76, no. 9, pp. 2118-2176. http://dx.doi.org/10.1111/j.1095-8649.2010.02684.x. PMid:20557657.
http://dx.doi.org/10.1111/j.1095-8649.20...
).

Concomitant to these changes, many invasive species have arrived emerged such as: Urochloa subquadripara (Trin.) R.D. Webster; Hydrilla verticillata (L.F.) Royle; Daphnia lumholtzii Sars, 1885; Corbicula fluminea Müller, 1774 and Limnoperna fortunei Dunker, 1857. Among these, Limnoperna fortunei commonly presents a high abundance and wide distribution in lotic environments of this floodplain (Agostinho et al., 2013AGOSTINHO, A.A., GOMES, L.C., BONECKER, C.C. and THOMAZ, S.M., 2013. Padrões de variação de longo prazo na planície de inundação do Alto do Rio Paraná. In: M. TABARELLI, C.F.D. ROCHA, P. ROMANOWSKI, O. ROCHA and L.D. LACERDA. PELD-CNPq: dez anos do programa de Pesquisas Ecológicas de Longa Duração: achados, lições e perspectivas. Recife: UFPE, pp. 165-196.).

Limnoperna fortunei Dunker, 1857, popularly known as golden mussel, is a freshwater bivalve (Darrigran and Ezcurra de Drago, 2000DARRIGRAN, G. and EZCURRA DE DRAGO, I., 2000. Distribución de (Dunker, 1857) (Mytilidae) em la cuenca del Plata, Región Neotropical. Limnoperna fortuneiMeio Ambiente, vol. 13, no. 2, pp. 75-79.) introduced into South America by vessel ballast water (Mansur et al., 1999MANSUR, M.C.D., RICHINITTI, L.M.Z. and SANTOS, C.P., 1999. (Dunker, 1857) molusco bivalve invasor na bacia do Guaíba, Rio Grande do Sul, Brasil. Limnoperna fortuneiBiociências, vol. 7, no. 2, pp. 147-149.; Darrigran and Pastorino, 1995DARRIGRAN, G. and PASTORINO, G., 1995. The recent introduction of Asiatic bivalve, (Mytilidae) into South America. Limnoperna fortuneiThe Veliger, vol. 38, pp. 183-187.). In Brazil, the first record was in 1999 (Mansur et al., 1999MANSUR, M.C.D., RICHINITTI, L.M.Z. and SANTOS, C.P., 1999. (Dunker, 1857) molusco bivalve invasor na bacia do Guaíba, Rio Grande do Sul, Brasil. Limnoperna fortuneiBiociências, vol. 7, no. 2, pp. 147-149.) in Rio Grande do Sul (Mansur et al., 2003MANSUR, M.C.D., SANTOS, C.P., DARRIGRAN, G., HEYDRICH, I., CALLIL, C.T. and CARDOSO, F., 2003. Primeiros dados quali-quantitativos do mexilhão-dourado, . Limnoperna fortunei (Dunker), no Delta do Jacuí, no Lago Guaíba e na Laguna dos Patos, Rio Grande do Sul, Brasil e alguns aspectos de sua invasão no novo ambienteRevista Brasileira de Zoologia, vol. 20, no. 1, pp. 75-84. http://dx.doi.org/10.1590/S0101-81752003000100009.
http://dx.doi.org/10.1590/S0101-81752003...
), with subsequent registers in aquatic environments of different states as São Paulo (Avelar et al., 2004AVELAR, W.E.P., MARTIM, S.L. and VIANNA, M.P., 2004. A new occurrence of (Dunker 1856) (Bivalvia, Mytilidae) in the State of São Paulo, Brazil. Limnoperna fortuneiBrazilian Journal of Biology = Revista Brasileira de Biologia, vol. 64, no. 4, pp. 739-742. http://dx.doi.org/10.1590/S1519-69842004000500002. PMid:15744413.
http://dx.doi.org/10.1590/S1519-69842004...
), Mato Grosso do Sul and Mato Grosso (Darrigran and Pastorino, 2003DARRIGRAN, G. and PASTORINO, G., 2003. The golden mussel (Dunker, 1857) (Bivalvia: Mytilidae) in the Neotropical region: a 10 years story of invasion. Limnoperna fortuneiTentacle, vol. 11, pp. 8-9.; Oliveira et al., 2006OLIVEIRA, M.D., TAKEDA, A.M., BARROS, L.F., BARBOSA, D.S. and RESENDE, E.K., 2006. Invasion by Limnoperna fortunei (Dunker, 1857) (Bivalvia, Mytilidae) of the Pantanal wetland, Brazil. Biological Invasions, vol. 8, no. 1, pp. 97-104. http://dx.doi.org/10.1007/s10530-005-0331-0.
http://dx.doi.org/10.1007/s10530-005-033...
) and Paraná (Takeda et al., 2003TAKEDA, A.M., MANSUR, M.C.D., FUJITA, D.S. and BIBIAN, J.P.R., 2003. Ocorrência da espécie invasora de mexilhão dourado, Limnoperna . fortunei (Dunker, 1857), em dois pequenos reservatórios próximos a Curitiba, PRActa Biologica Leopondensia, vol. 25, no. 2, pp. 251-254.).

The invasion success of this species is intrinsically related to the biological characteristics of its life cycle (Lodge et al., 1998LODGE, D.M., STEIN, R.A., BROWN, K.M., COVICH, A.P., BRONMARK, C., GARVEY, J. and KLOSIEWSKT, S.P., 1998. Predicting impact of freshwater exotic species on native biodiversity: Challenges in spatial scaling. Australian Journal of Ecology, vol. 23, no. 1, pp. 53-67. http://dx.doi.org/10.1111/j.1442-9993.1998.tb00705.x.
http://dx.doi.org/10.1111/j.1442-9993.19...
). A planktonic larval stage and an adult phase with encrusting capacity ensure a great spreading ability and potential of colonizing new areas. Initial stages of development are easily carried by water flow to new environments, while the latter stages tend to disperse due to traffic of vessels between connected water bodies. Among these phases, Oliveira et al. (2004)OLIVEIRA, M.D., PELLEGRIN, L.A., BARRETO, R.R., SANTOS, C.L. and XAVIER, I.G., 2004. Área de ocorrência do Mexilhão Dourado na bacia do Alto Paraguai, entre os anos de 1998 e 2004. Corumbá: Embrapa Pantanal. 19 p. Documentos, vol. 64. consider that the larval stage is the most favorable for dispersion.

This specie feeds on suspended material in the water column (Sylvester et al., 2009SYLVESTER, F., BOLTOVSKOY, D. and CATALDO, D., 2009. Taxas de clareamento: ritmos e impactos. In: G. DARRIGRAN and C. DAMBORENEA. Introdução a biologia das invasões: o mexilhão dourado na América do Sul: biologia, impacto, prevenção e controle. São Carlos: Cubo, pp. 246.), such as the zooplankton community and, especially, the phytoplankton community (Fachini et al., 2012FACHINI, A., GAZULHA, V. and PEDROSO, C.S., 2012. Os impactos do mexilhão-dourado sobre a comunidade planctônica. In: M.C.D. MANSUR, C.P. SANTOS, D. PEREIRA, I.C.P. PAZ, M.L.L. ZURITA, M.T.R. RODRIGUEZ, M.V. NEHRKE and P.E.A. BERGONCI. Moluscos límnicos invasores do Brasil: biologia, prevenção e controle. Porto Alegre: Redes Editora, pp. 255-261.). Although the latter represents a small fraction of the diet of L. fortunei, phytoplankton is responsible for supplying more than 90% of the energy demand required by the specie at certain seasons (Sylvester et al., 2009SYLVESTER, F., BOLTOVSKOY, D. and CATALDO, D., 2009. Taxas de clareamento: ritmos e impactos. In: G. DARRIGRAN and C. DAMBORENEA. Introdução a biologia das invasões: o mexilhão dourado na América do Sul: biologia, impacto, prevenção e controle. São Carlos: Cubo, pp. 246.). In addition to food resources, some abiotic factors seem to facilitate the establishment of L. fortunei, such as oxygen content and water temperature (Darrigran and Pastorino, 1995DARRIGRAN, G. and PASTORINO, G., 1995. The recent introduction of Asiatic bivalve, (Mytilidae) into South America. Limnoperna fortuneiThe Veliger, vol. 38, pp. 183-187.; Boltovskoy and Cataldo, 1999BOLTOVSKOY, D. and CATALDO, D., 1999. Population dynamics of . Limnoperna fortunei, an Invasive fouling mollusc, in the Lower Paran River (Argentina)Biofouling, vol. 14, no. 3, pp. 255-263. http://dx.doi.org/10.1080/08927019909378417.
http://dx.doi.org/10.1080/08927019909378...
; Mansur et al., 2003MANSUR, M.C.D., SANTOS, C.P., DARRIGRAN, G., HEYDRICH, I., CALLIL, C.T. and CARDOSO, F., 2003. Primeiros dados quali-quantitativos do mexilhão-dourado, . Limnoperna fortunei (Dunker), no Delta do Jacuí, no Lago Guaíba e na Laguna dos Patos, Rio Grande do Sul, Brasil e alguns aspectos de sua invasão no novo ambienteRevista Brasileira de Zoologia, vol. 20, no. 1, pp. 75-84. http://dx.doi.org/10.1590/S0101-81752003000100009.
http://dx.doi.org/10.1590/S0101-81752003...
; Cataldo et al., 2005CATALDO, D., BOLTOVSKOY, D., HERMOSA, J.L. and CANZI, C., 2005. Temperature dependent larval development rates of (Mollusca, Bivalvia). Limnoperna fortuneiThe Journal of Molluscan Studies, vol. 71, pp. 41-46. http://dx.doi.org/10.1093/mollus/eyi005.
http://dx.doi.org/10.1093/mollus/eyi005...
; Darrigran et al., 2007DARRIGRAN, G., DAMBORENEA, C. and GRECO, N., 2007. An evaluation pattern for antimacrofouling procedures: larvae in a hydroelectric power plant in South America. Limnoperna fortuneiAmbio, vol. 36, no. 7, pp. 575-579. http://dx.doi.org/10.1579/0044-7447(2007)36[575:AEPFAP]2.0.CO;2. PMid:18074895.
http://dx.doi.org/10.1579/0044-7447(2007...
; Pestana et al., 2010PESTANA, D., OSTRENSKY, A., TSCHÁ, M.K. and BOEGER, W.A., 2010. Prospecção do molusco invasor Limnoperna fortunei (Dunker, 1857) nos principais corpos hídricos do estado do Paraná, Brasil. Papéis Avulsos de Zoologia, vol. 50, no. 34, pp. 553-559. http://dx.doi.org/10.1590/S0031-10492010003400001.
http://dx.doi.org/10.1590/S0031-10492010...
).

The objective of this study was to investigate the distribution of L. fortunei larvae and correlate their abundance with phytoplankton community and abiotic factors. We tested the hypothesis that the availability of palatable phytoplankton and favorable abiotic factors contributes to high densities of L. fortunei larvae. Our predictions were: (i) environments with high densities of algae and high values of dissolved oxygen and temperature will present higher densities of L. fortunei larvae (ii) environments with higher densities of nanophytoplankton will have higher density of larvae in early stages as D and Straight-hinged larvae.

2 Material and Methods

2.1 Study area

This study was conducted in the Upper Paraná River floodplain (Paraná, Brazil). The sampling area stretched from cities Três Lagoas (Mato Grosso do Sul, Brazil) to Guaíra (Paraná, Brazil), between the Porto Primavera and Itaipu dams, approximately 230 km and cover an area of 526,752 ha (Souza Filho and Stevaux, 1997SOUZA FILHO, E.E. and STEVAUX, J.C., 1997. Geologia e geomorfologia do complexo rio Baia, Curutuba, Ivinheima. In: A.E.A.M. VAZZPLER, A.A. AGOSTINHO and N.S.A. HAHN. A planície de inundação do alto rio Paraná: aspectos físicos, biológicos e socioeconômicos. Maringá: Editora da Universidade Estadual de Maringá, pp. 3-46.). Samples were collected at 5 stations (Figure 1).

Figure 1
Sampling stations in the Paraná River floodplain. (1) Paraná River (main channel); (2) Baía River (main channel); (3) Curutuba Channel (secondary channel); (4) Ivinhema River (main channel); (5) Ipoitã Channel (secondary channel).

The stretch of the floodplain presents a braided channel, with high levels of current flow, and channel of varying widths with extensive islands (Pauleto et al., 2009PAULETO, G.M., VELHO, L.F.M., BUOSI, P.R.B., BRÃO, A.F.S., LANSAC-TÔHA, F.A. and BONECKER, C.C., 2009. Spatial and temporal patterns of ciliate species composition (Protozoa: Ciliophora) in the plankton of the Upper Paraná River floodplain. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 517-527. http://dx.doi.org/10.1590/S1519-69842009000300007. PMid:19738959.
http://dx.doi.org/10.1590/S1519-69842009...
). The mean depth of the river is about 4.0 m and may reach 15.0 m at this stretch (Thomaz et al., 1992THOMAZ, S.M., ROBERTO, M.C., LANSAC TOHA, F.A., LIMA, F.A. and ESTEVES, F.A., 1992. Características limnológicas de uma estação de amostragem do Alto Rio Paraná e outra do Baixo Rio Ivinhema. Acta Limnologica Brasiliensia, vol. 4, pp. 32-52.). Samples were taken in the Paraná River (22° 75’ 68” - 53° 25’ 31”), Ivinhema River (22° 51’ 23” S - 53º 36’ 23” W) and Ipoitã Channel (22° 83’ 59” - 53° 56’ 37”). This channel which connects the Paraná and Ivinhema rivers is one of main tributaries situated on the right bank of the Paraná River (Pauleto et al., 2009PAULETO, G.M., VELHO, L.F.M., BUOSI, P.R.B., BRÃO, A.F.S., LANSAC-TÔHA, F.A. and BONECKER, C.C., 2009. Spatial and temporal patterns of ciliate species composition (Protozoa: Ciliophora) in the plankton of the Upper Paraná River floodplain. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 517-527. http://dx.doi.org/10.1590/S1519-69842009000300007. PMid:19738959.
http://dx.doi.org/10.1590/S1519-69842009...
).Samples were also taken in the Baía River (22° 72’ 31” - 53° 29’ 04”) which is connected to the Paraná River through the Baía Channel. In addition to the main channel, samples were taken in Curutuba Channel (22° 75’ 32” - 53° 35’ 85”) which connects Baia River to Ivinhema River (Pauleto et al., 2009PAULETO, G.M., VELHO, L.F.M., BUOSI, P.R.B., BRÃO, A.F.S., LANSAC-TÔHA, F.A. and BONECKER, C.C., 2009. Spatial and temporal patterns of ciliate species composition (Protozoa: Ciliophora) in the plankton of the Upper Paraná River floodplain. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 517-527. http://dx.doi.org/10.1590/S1519-69842009000300007. PMid:19738959.
http://dx.doi.org/10.1590/S1519-69842009...
). Baía River is a lentic water environment with varied width, a mean depth of 3.2 m, low declivity and low current flow and is directly influenced by the hydrological regime of Paraná River (Thomaz et al., 1992THOMAZ, S.M., ROBERTO, M.C., LANSAC TOHA, F.A., LIMA, F.A. and ESTEVES, F.A., 1992. Características limnológicas de uma estação de amostragem do Alto Rio Paraná e outra do Baixo Rio Ivinhema. Acta Limnologica Brasiliensia, vol. 4, pp. 32-52.).

2.2 Sampling

Samples of larval density were taken in March, June, September and December of 2012, in the central regions of Paraná, Ivinhema and Baía rivers and Ipoitã and Curutuba channels. At each station we filtered three samples of 100 L in the water column (approximately 0.5m deep), with plankton net with mesh size of 30 μm. After filtration, the material was fixed in 80% alcohol.

Concomitantly, we took measurements at each sampling point of the following variables: water temperature (°C), turbidity (NTU), PO4- phosphate (μg/L); NO3-nitrate (μg/L), NH4- ammonia (μg/L); SOM: suspended organic matter (mg/L); SIM= suspended inorganic matter (mg/L), electric conductivity (μS/cm), D.O= dissolved oxygen (mg/L) provided by the laboratory of Limnology NUPÉLIA.

The water level of the river was taken daily by reading a ruler installed at the margins of Paraná River. Measurements were taken in the morning and afternoon, resulting in a daily average, which were later transformed into monthly averages for some analyzes. The river level data were expanded for the all environments because the Paraná River constantly influences these areas.

In the laboratory, larvae of L. fortunei were counted under stereo microscope. The abundance of organisms was evaluated by full counting, except in samples presenting extremely high densities of individuals, in which we realized three subsequent sub-samplings obtained with Hensen Stempell pipettes (2.5 mL).

Larvae valves of L. fortunei were measured for length and width and classified into larvae stages according to the methods adopted by Santos et al. (2005)SANTOS, C.P., WÜRDIG, N.L. and MANSUR, M.C.D., 2005. Fases larvais do mexilhão dourado (Dunker) (Mollusca, Bivavia, Mytilidae) na bacia do Guaíba, Rio Grande do Sul, Brasil. Limnoperna fortuneiRevista Brasileira de Zoologia, vol. 22, no. 3, pp. 702-708. http://dx.doi.org/10.1590/S0101-81752005000300029.
http://dx.doi.org/10.1590/S0101-81752005...
and Ezcurra de Drago et al. (2006)EZCURRA DE DRAGO, I., MONTALTO, L. and OLIVEROS, O.B., 2006. Desarrollo y ecología larval de Limnoperna fortunei. In: G. DARRIGRAN and M.C. DAMBORENEA. Bioinvasion del mejillón dorado en el continente americano. Argentina: EDULP, pp. 85-93.. Furthermore, for the analysis, we classified larvae into five categories according to the size of their valves: D (90-130 μm), Straight-hinged (140-180μm), Umbonated (190-220 μm), Pediveliger (230-270 μm) and Plantigrader (280-490 μm) (Figure 2).

Figure 2
Larval stages with the scale bars. (a) D larvae, 90-130 μm; (b) Straight-hinged, 140-180μm; (c) Umbonated, 190-220 μm; (d) Pediveliger, 230-270 μm; (e) Plantigrader, 280-490 μm.

Sampling of phytoplankton was carried out directly at the water’s subsurface (20 cm depth). Phytoplankton samples were preserved with acidified Lugol’s solution. The phytoplankton density was estimated according to Utermöhl (1958)UTERMÖHL, H., 1958. Zur Vervollkommnung der quantitativen phytoplankton methodike. Mitteilungen - Internationale Vereinigung für Theoretische und Angewandte Limnologie, vol. 9, pp. 1-38. and Lund et al. (1958)LUND, J.W.G., KIPLING, C. and LECREN, E.D., 1958. The inverted microscope method of estimating algal number and the statistical basis of estimating by counting. Hydrobiologia, vol. 11, no. 2, pp. 980-985. http://dx.doi.org/10.1007/BF00007865.
http://dx.doi.org/10.1007/BF00007865...
, and the species richness was considered as the number of taxa present in one hundred fields of microscope in each quantitative sample. In the case of samples with low density algae, we used the method of curve stabilization. The phytoplankton biovolume was estimated by multiplying the density of different taxa by their respective volumes. The volume of each cell was calculated from geometric models approximating the form of individuals (Sun and Liu, 2003SUN, J. and LIU, D., 2003. Geometric models for calculating cell biovolume and surface area for phytoplankton. Journal of Plankton Research, vol. 25, no. 2, pp. 1331-1346. http://dx.doi.org/10.1093/plankt/fbg096.
http://dx.doi.org/10.1093/plankt/fbg096...
).

2.3 Statistical analysis

To make the graphic of hydrometric levels of the river and the periods of high and low water we used the average of the measurements (morning and afternoon) of the Paraná River, at the base of Porto Rico-PR provided by the NUPÉLIA.

To verify the influence of abiotic variables, we used a principal component analysis (PCA), using PC-ORD 5.0 software (McCune and Mefford, 1999MCCUNE, B. and MEFFORD, M.J., 1999. PC-Ord: multivariate analysis of ecological data. Version 4.0. Gleneden Blach: MjM Software Design.). Axes were retained for interpretations according to the Broken-Stick criteria. The variables used in the ordination were depth (m), pH, temperature (°C), conductivity (μS/cm), and dissolved oxygen (mg/L), turbidity (NTU), Secchi (m), suspended inorganic matter- SIM (mg/L), suspended organic matter – SOM (mg/L), NT = total nitrogen (µg / L), PT = total phosphorus (µg / L), PO4 (µg/L), NO3 (µg/L), NH4 (µg/L), measured at Nupélia.

To summarize the biotic and abiotic data we used the Canonical Correspondence Analysis (CCA) (Ter Braak, 1986TER BRAAK, C.J.F., 1986. Canonical correspondence analysis: a new eigenvector technique for multivariate direct gradient analysis. Ecology, vol. 67, no. 5, pp. 1167-1179. http://dx.doi.org/10.2307/1938672.
http://dx.doi.org/10.2307/1938672...
; Legendre and Legendre, 1998LEGENDRE, P. and LEGENDRE, L., 1998. Numerical ecology. 2nd ed. Amsterdam: Elsevier. 853 p.). This analysis is a multivariate ordination performed to verify the grouping between points and identify the factors that most influence axes.

3 Results

The water level had two high periods in January and June, and the samples were taken after these periods of floods. According to Souza Filho (2009)SOUZA FILHO, E.E., 2009. Evaluation of the Upper Paraná River discharge controlled by reservoirs. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 707-716. http://dx.doi.org/10.1590/S1519-69842009000300024. PMid:19738976.
http://dx.doi.org/10.1590/S1519-69842009...
, when the level of the Paraná River is below 3.5 meters, it is considered a period of low water for all environments of the floodplain, therefore our sampling were made in the dry seasons (Figure 3).

Figure 3
Daily data of the river Paraná level (m) in 2012, obtained from the fluviometric station of Porto Rico-PR, the research base of the NUPÉLIA.

The PCA results of explained 65.4% (axis 1 = 41.8% and axis 2 = 23.6%), and showed that no temporal differences between samplings. The results also evidenced a clear distinction of three spatial groups. The first one included Baía River and Curutuba Channel, which was influenced by PT (total phosphorus) and PO4; the second one included Paraná River and Ipoitã Channel that correlated with dissolved oxygen (D.O); and finally an isolated group of samples from Ivinhema River which was correlated with turbidity and suspended inorganic materials (SIM) (Figure 4).

Figure 4
Principal component analysis (PCA) of environments and abiotic variables. BAI= Baía River, IVI= Ivinhema River, PAR= Paraná River, CUR= Curutuba Channel e IPO= Ipoitã Channel (M= March, J= June, S= September e D= December) and (PT= total phosphorus, S.I.M= suspended inorganic material, D.O= dissolved oxygen).

The larvae density distribution of L. fortunei follows a temporal pattern, in which the highest densities were recorded in December, particularly Baía River (Figure 5a). Algae densities did not show any temporal pattern. The highest densities were recorded in the Paraná river and Baía River in September (BAI-S) and Baía River in December (BAI-D) with the highest density values for the Bacillariophyceae microplankton and Bacillariophyceae nanoplankton (Figure 5b).

Figure 5
Larvae density (five stages) of L. fortunei in the sampled environments of the Upper Paraná River floodplain. (a) Algae density in the sampled environments of Upper Paraná River floodplain; (b) PAR= Paraná River; IPO= Ipoita channel; IVI= Ivinhema River; CUR= Curutuba channel; BAI= Baía River, M= March; J= June; S= September D= December; Mic= microphytoplankton; Nan= nanophytoplankton; BAC= Bacillariophyceae, CYA= Cyanobacteria, CHL= Chlorophyceae, CHY= Chrysophyceae, EUG= Euglenophyceae, CRY= Cryptophyceae, ZYG= Zygnemaphyceae, XAN= Xanthophyceae, DIN= Dinophyceae, RAP= Raphyceae, OED= Oedogoniophyceae.

Considering the Canonical Correspondence Analysis (CCA), the two first axes were significant (p <0.05) explaining 84% (Figure 6). There was a correlation between the first larval stage (D Larvae) with some abiotic factors, such as temperature, PO4 and phytoplankton density (Figure 6a). Phytoplankton species were composed primarily by Cholorophyceae and Zygnemaphyceae microphytoplankton (63-500 µm) (Figure 6c) in the environments Baia River in March (BAI-M), Baía River in December (BAI-D), Paraná River in December (PAR-D) and Curutuba Channel in December (CUR-D) (Figure 6b). The other larval stages (Straight-hinged, Umbonated, Pediveliger and Plantigrader) correlated primarily with conductivity, pH, NO3 and only the Dinophyceae nanoplankton (2-63 µm) (Figures 6a, 6b and 6c).

Figure 6
Canonical Correspondence Analysis (CCA). (a) Correlation of abiotic variables: temperature, turbidity, chlorophyll, PO4 (phosphate); NO3 (nitrate), NH4 (ammonia); S.O.M: suspended organic matter; S.I.M= suspended inorganic matter, conductivity, D.O= dissolved oxygen; (b) Correlation of the environments and months (samples). PAR= Paraná River; IPO= Ipoita channel; IVI= Ivinhema River; CUR= Curutuba channel; BAI= Baía River, M= March; J= June; S= September D= December; (c) Correlation of algae and larval stages. BAC= Bacillariophyceae, CYA= Cyanobacteria, CHL= Chlorophyceae, CHY= Chrysophyceae, EUG= Euglenophyceae, CRY= Cryptophyceae, ZYG= Zygnemaphyceae, XAN= Xanthophyceae, DIN= Dinophyceae, RAP= Raphyceae, OED= Oedogoniophyceae, Micro= microphytoplankton; Nano= nanophytoplankton.

4 Discussion

Our initial hypothesis was corroborated, because the period of reproductive activity of L. fortunei was positively correlated with high densities of phytoplankton, although there is no evidence that this correlation is direct. The presence of dissolved nutrients may have favored the proliferation of phytoplankton and high temperature in December probably induced the reproduction of the golden mussel.

Thus, the phytoplankton community may have contributed indirectly to the high densities of D larvae, due to high food source for adults of the species. Studies about the diet of this bivalve using the plankton community were performed by Pace et al. (1998)PACE, M.L., FINDLAY, S.E.G. and FISCHER, D., 1998. Effects of an invasive bivalve on the zooplankton community of the Hudson River. Freshwater Biology, vol. 39, no. 1, pp. 103-116. http://dx.doi.org/10.1046/j.1365-2427.1998.00266.x.
http://dx.doi.org/10.1046/j.1365-2427.19...
, Thorp and Casper (2002)THORP, J.H. and CASPER, A.F., 2002. Potential effects on zooplankton from species shifts in planktivorous mussels: a field experiment in the St Lawrence River. Freshwater Biology, vol. 47, no. 1, pp. 107-119. http://dx.doi.org/10.1046/j.1365-2427.2002.00787.x.
http://dx.doi.org/10.1046/j.1365-2427.20...
, Rojas Molina et al. (2010)ROJAS MOLINA, F., PAGGI, J.C. and DEVERCELLI, M., 2010. Zooplanktophagy in the natural diet and selectivity of the invasive moluk Limnoperna fortunei.Biological Invasions, vol. 12, no. 6, pp. 1647-1659. http://dx.doi.org/10.1007/s10530-009-9578-1.
http://dx.doi.org/10.1007/s10530-009-957...
, which evidenced that the availability of food is intimately related with the reproduction of L. fortunei.

The principal component analysis (PCA) did not show temporal differences between samples but a spatial difference between environments was verified. The absence of temporal differences in abiotic variables was because the samples were not taken in high water periods.

The Canonical Correspondence Analysis (CCA) showed a clear separation between the first larval stage and the others. The first stage was correlated with temperature and the other stages with the high concentration of dissolved oxygen, conductivity and pH. Studies by Cataldo et al. (2005)CATALDO, D., BOLTOVSKOY, D., HERMOSA, J.L. and CANZI, C., 2005. Temperature dependent larval development rates of (Mollusca, Bivalvia). Limnoperna fortuneiThe Journal of Molluscan Studies, vol. 71, pp. 41-46. http://dx.doi.org/10.1093/mollus/eyi005.
http://dx.doi.org/10.1093/mollus/eyi005...
, Darrigran et al. (2007)DARRIGRAN, G., DAMBORENEA, C. and GRECO, N., 2007. An evaluation pattern for antimacrofouling procedures: larvae in a hydroelectric power plant in South America. Limnoperna fortuneiAmbio, vol. 36, no. 7, pp. 575-579. http://dx.doi.org/10.1579/0044-7447(2007)36[575:AEPFAP]2.0.CO;2. PMid:18074895.
http://dx.doi.org/10.1579/0044-7447(2007...
, Kimura and Sekiguchi (1996)KIMURA, T. and SEKIGUCHI, H., 1996. Effects of temperature on larval development of two mytilid species and their implication. Venus, vol. 55, pp. 215-222., Cataldo and Boltovskoy (2000)CATALDO, D. and BOLTOVSKOY, D., 2000. Yearly reproductive activity . of Limnoperna fortunei (Bivalvia) as inferred from the occurrence of its larvae in the plankton of the lower Paraná river and the Río de la Plata estuary (Argentina)Aquatic Ecology, vol. 34, no. 3, pp. 307-317. http://dx.doi.org/10.1023/A:1009983920942.
http://dx.doi.org/10.1023/A:100998392094...
and Oliveira et al. (2011)OLIVEIRA, M.D., CALHEIROS, D.F., JACOBI, C.M. and HAMILTON, S.K., 2011. Abiotic factors controlling the establishment and abundance of the invasive golden mussel Limnoperna fortunei.Biological Invasions, vol. 13, no. 3, pp. 717-729. http://dx.doi.org/10.1007/s10530-010-9862-0.
http://dx.doi.org/10.1007/s10530-010-986...
suggest that temperature is fundamental for the reproduction, while water oxygenation is important to the development of individuals.

In this way, the high temperatures of the studied region may favor the golden mussel population, due to the constant emission of propagules. In the tropical region average temperatures are higher than in the home range of L. fortunei, for example in China where the average maximum is about 27.8 °C (Ho et al., 2003HO, K.C., CHOW, Y.L. and YAU, J.T., 2003. Chemical and micro-biological qualities of the East River (Dongjiang) water, with particular reference to drinking water supply in Hong Kong. Chemosphere, vol. 52, no. 9, pp. 1441-1450. http://dx.doi.org/10.1016/S0045-6535(03)00481-8. PMid:12867174.
http://dx.doi.org/10.1016/S0045-6535(03)...
).

Considering the results we obtained, our first prediction was satisfied, that is, the reproduction of L. fortunei was correlated with phytoplankton and high temperatures. However, the relationship of the reproduction with the values of dissolved oxygen was not found. This variable was positively correlated with the other larval stages, which shows its importance for larval development, and not for the reproduction of the species.

Among the groups of algae correlated with higher densities of D larvae, the most important was Chlorophyceae, probably because this group of algae is rich in assimilates and does not produce toxins (Happey-Wood, 1988HAPPEY-WOOD, C.M., 1988. Ecology of freshwater planktonic green algae. In: C.D. SANDGREN. Growth and reproductive strategies of freshwater phytoplankton. New York: Cambridge University Press, pp. 175-226.). Thus, the nutritional contribution during this period may be even stronger for the reproduction of L. fortunei, since the abiotic factors such as temperature during this period were favorable.

Although high densities of Bacillariophyceae coincided with the period of reproduction, they were not correlated with high larvae densities. The explanation for this may be in these algae silica capsules (Sommer, 1988SOMMER, U., 1988. Growth and survival strategies of planktonic diatoms. In: C.D. SANDGREN. Growth and reproductive strategies of freshwater phytoplankton. New York: Cambridge University Press, pp. 227-260.), which hinder their digestion. This group of algae are difficult to digest, and has been reported in golden mussel pseudofeces (Fachini et al., 2012FACHINI, A., GAZULHA, V. and PEDROSO, C.S., 2012. Os impactos do mexilhão-dourado sobre a comunidade planctônica. In: M.C.D. MANSUR, C.P. SANTOS, D. PEREIRA, I.C.P. PAZ, M.L.L. ZURITA, M.T.R. RODRIGUEZ, M.V. NEHRKE and P.E.A. BERGONCI. Moluscos límnicos invasores do Brasil: biologia, prevenção e controle. Porto Alegre: Redes Editora, pp. 255-261.).

The D Larvae represent the first valved larval stage, and are able to filter their food (Darrigran and Damborenea, 2009DARRIGRAN, G. and DAMBORENEA, C., 2009. Características da espécie. In: G. DARRIGRAN and C. DAMBORENEA. Introdução a biologia das invasões: o mexilhão dourado na América do Sul: biologia, impacto, prevenção e controle. São Carlos: Cubo, pp. 43-60.). The small sizes of the particles are selected by their siphons, primarily by size (Vanderploeg et al., 2001VANDERPLOEG, H.A., LIEBIG, J.R., CARMICHAEL, W.W., AGY, M.A., JOHENGEN, T.H., FAHNENSTIEL, G.F. and NALEPA, T.F., 2001. Zebra mussel (Dreissena polymorphaMicrocystis) selective filtration promoted toxic blooms in Saginaw Bay (Lake Huron) and Lake Erie. Canadian Journal of Fisheries and Aquatic Sciences, vol. 58, no. 6, pp. 1208-1221. http://dx.doi.org/10.1139/f01-066.
http://dx.doi.org/10.1139/f01-066...
). Thus, the correlation between the larval stage and nanophytoplankton may favor the development of these larvae. This corroborates the second prediction, but only for D larvae, and the correlation was not found for the straight-hinged stage.

We found a strong correlation of D larvae with nanoplanktonic and microplanktonic algae. This can be explained by the influence of both sizes of algae on the adults of the species. In other words, both the micro and the nanophytoplankton contribute to high densities of D larvae by favoring high reproductive rates of adults.

The results showed high values for the larval density, but the most significant numbers are restricted to early stages. Therefore, the mortality rate seems high, since the large number of D larvae and straight-hinged indicates that there are places where the population is established and continually reproducing. This is alarming, because the stability of an invasive population in integrated environment can assurance the emission of propagules to environments not yet invaded and cause colonization.

We conclude that higher temperatures contributed for that the initial phases had high densities, and that, this probably is related to increased source of food, as indicated by the increased biovolume the phytoplankton community. The phytoplankton community, independent of the size, contributed to increase L. fortunei larvae density because influence about adults of this specie.

The presences of adults in the determined locations indicate a larva already installed and is able to develop these new habitats. Therefore, to prevent the dispersion of these individuals it is necessary to understand the mechanisms of survival in basal levels of development. Understanding the process related to the development of larval stages would provide tools and information for conservation and management of aquatic environments, in order to of preventing the establishment of these individuals instead of manage the specie already established.

Acknowledgements

The authors are grateful for the financial support of the PELD (Programa Ecológico de Longa Duração)/ CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico)/ Nupelia (Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura)

  • (With 6 figures)

References

  • AGOSTINHO, A.A., GOMES, L.C., BONECKER, C.C. and THOMAZ, S.M., 2013. Padrões de variação de longo prazo na planície de inundação do Alto do Rio Paraná. In: M. TABARELLI, C.F.D. ROCHA, P. ROMANOWSKI, O. ROCHA and L.D. LACERDA. PELD-CNPq: dez anos do programa de Pesquisas Ecológicas de Longa Duração: achados, lições e perspectivas. Recife: UFPE, pp. 165-196.
  • AVELAR, W.E.P., MARTIM, S.L. and VIANNA, M.P., 2004. A new occurrence of (Dunker 1856) (Bivalvia, Mytilidae) in the State of São Paulo, Brazil. Limnoperna fortuneiBrazilian Journal of Biology = Revista Brasileira de Biologia, vol. 64, no. 4, pp. 739-742. http://dx.doi.org/10.1590/S1519-69842004000500002. PMid:15744413.
    » http://dx.doi.org/10.1590/S1519-69842004000500002
  • BARLETTA, M., JAUREGUIZAR, A.J., BAIGUN, C., FONTOURA, N.F., AGOSTINHO, A.A., ALMEIDA-VAL, V.M.F., VAL, A.L., TORRES, R.A., JIMENES-SEGURA, L.F., GIARRIZZO, T., FABRÉ, N.N., BATISTA, V.S., LASSO, C., TAPHORN, D.C., COSTA, M.F., CHAVES, P.T., VIEIRA, J.P. and CORRÊA, M.F.M., 2010. Fish and aquatic habitat conservation in South America: a continental overview with emphasis on neotropical systems. Journal of Fish Biology, vol. 76, no. 9, pp. 2118-2176. http://dx.doi.org/10.1111/j.1095-8649.2010.02684.x. PMid:20557657.
    » http://dx.doi.org/10.1111/j.1095-8649.2010.02684.x
  • BOLTOVSKOY, D. and CATALDO, D., 1999. Population dynamics of . Limnoperna fortunei, an Invasive fouling mollusc, in the Lower Paran River (Argentina)Biofouling, vol. 14, no. 3, pp. 255-263. http://dx.doi.org/10.1080/08927019909378417.
    » http://dx.doi.org/10.1080/08927019909378417
  • CATALDO, D. and BOLTOVSKOY, D., 2000. Yearly reproductive activity . of Limnoperna fortunei (Bivalvia) as inferred from the occurrence of its larvae in the plankton of the lower Paraná river and the Río de la Plata estuary (Argentina)Aquatic Ecology, vol. 34, no. 3, pp. 307-317. http://dx.doi.org/10.1023/A:1009983920942.
    » http://dx.doi.org/10.1023/A:1009983920942
  • CATALDO, D., BOLTOVSKOY, D., HERMOSA, J.L. and CANZI, C., 2005. Temperature dependent larval development rates of (Mollusca, Bivalvia). Limnoperna fortuneiThe Journal of Molluscan Studies, vol. 71, pp. 41-46. http://dx.doi.org/10.1093/mollus/eyi005.
    » http://dx.doi.org/10.1093/mollus/eyi005
  • DARRIGRAN, G. and PASTORINO, G., 2003. The golden mussel (Dunker, 1857) (Bivalvia: Mytilidae) in the Neotropical region: a 10 years story of invasion. Limnoperna fortuneiTentacle, vol. 11, pp. 8-9.
  • DARRIGRAN, G. and PASTORINO, G., 1995. The recent introduction of Asiatic bivalve, (Mytilidae) into South America. Limnoperna fortuneiThe Veliger, vol. 38, pp. 183-187.
  • DARRIGRAN, G. and DAMBORENEA, C., 2009. Características da espécie. In: G. DARRIGRAN and C. DAMBORENEA. Introdução a biologia das invasões: o mexilhão dourado na América do Sul: biologia, impacto, prevenção e controle. São Carlos: Cubo, pp. 43-60.
  • DARRIGRAN, G., DAMBORENEA, C. and GRECO, N., 2007. An evaluation pattern for antimacrofouling procedures: larvae in a hydroelectric power plant in South America. Limnoperna fortuneiAmbio, vol. 36, no. 7, pp. 575-579. http://dx.doi.org/10.1579/0044-7447(2007)36[575:AEPFAP]2.0.CO;2. PMid:18074895.
    » http://dx.doi.org/10.1579/0044-7447(2007)36[575:AEPFAP]2.0.CO;2
  • DARRIGRAN, G. and EZCURRA DE DRAGO, I., 2000. Distribución de (Dunker, 1857) (Mytilidae) em la cuenca del Plata, Región Neotropical. Limnoperna fortuneiMeio Ambiente, vol. 13, no. 2, pp. 75-79.
  • EZCURRA DE DRAGO, I., MONTALTO, L. and OLIVEROS, O.B., 2006. Desarrollo y ecología larval de Limnoperna fortunei. In: G. DARRIGRAN and M.C. DAMBORENEA. Bioinvasion del mejillón dorado en el continente americano. Argentina: EDULP, pp. 85-93.
  • FACHINI, A., GAZULHA, V. and PEDROSO, C.S., 2012. Os impactos do mexilhão-dourado sobre a comunidade planctônica. In: M.C.D. MANSUR, C.P. SANTOS, D. PEREIRA, I.C.P. PAZ, M.L.L. ZURITA, M.T.R. RODRIGUEZ, M.V. NEHRKE and P.E.A. BERGONCI. Moluscos límnicos invasores do Brasil: biologia, prevenção e controle. Porto Alegre: Redes Editora, pp. 255-261.
  • HAPPEY-WOOD, C.M., 1988. Ecology of freshwater planktonic green algae. In: C.D. SANDGREN. Growth and reproductive strategies of freshwater phytoplankton. New York: Cambridge University Press, pp. 175-226.
  • HO, K.C., CHOW, Y.L. and YAU, J.T., 2003. Chemical and micro-biological qualities of the East River (Dongjiang) water, with particular reference to drinking water supply in Hong Kong. Chemosphere, vol. 52, no. 9, pp. 1441-1450. http://dx.doi.org/10.1016/S0045-6535(03)00481-8. PMid:12867174.
    » http://dx.doi.org/10.1016/S0045-6535(03)00481-8
  • KIMURA, T. and SEKIGUCHI, H., 1996. Effects of temperature on larval development of two mytilid species and their implication. Venus, vol. 55, pp. 215-222.
  • LEGENDRE, P. and LEGENDRE, L., 1998. Numerical ecology. 2nd ed. Amsterdam: Elsevier. 853 p.
  • LODGE, D.M., STEIN, R.A., BROWN, K.M., COVICH, A.P., BRONMARK, C., GARVEY, J. and KLOSIEWSKT, S.P., 1998. Predicting impact of freshwater exotic species on native biodiversity: Challenges in spatial scaling. Australian Journal of Ecology, vol. 23, no. 1, pp. 53-67. http://dx.doi.org/10.1111/j.1442-9993.1998.tb00705.x.
    » http://dx.doi.org/10.1111/j.1442-9993.1998.tb00705.x
  • LUND, J.W.G., KIPLING, C. and LECREN, E.D., 1958. The inverted microscope method of estimating algal number and the statistical basis of estimating by counting. Hydrobiologia, vol. 11, no. 2, pp. 980-985. http://dx.doi.org/10.1007/BF00007865.
    » http://dx.doi.org/10.1007/BF00007865
  • MANSUR, M.C.D., SANTOS, C.P., DARRIGRAN, G., HEYDRICH, I., CALLIL, C.T. and CARDOSO, F., 2003. Primeiros dados quali-quantitativos do mexilhão-dourado, . Limnoperna fortunei (Dunker), no Delta do Jacuí, no Lago Guaíba e na Laguna dos Patos, Rio Grande do Sul, Brasil e alguns aspectos de sua invasão no novo ambienteRevista Brasileira de Zoologia, vol. 20, no. 1, pp. 75-84. http://dx.doi.org/10.1590/S0101-81752003000100009.
    » http://dx.doi.org/10.1590/S0101-81752003000100009
  • MANSUR, M.C.D., RICHINITTI, L.M.Z. and SANTOS, C.P., 1999. (Dunker, 1857) molusco bivalve invasor na bacia do Guaíba, Rio Grande do Sul, Brasil. Limnoperna fortuneiBiociências, vol. 7, no. 2, pp. 147-149.
  • MCCUNE, B. and MEFFORD, M.J., 1999. PC-Ord: multivariate analysis of ecological data. Version 4.0. Gleneden Blach: MjM Software Design.
  • OLIVEIRA, M.D., CALHEIROS, D.F., JACOBI, C.M. and HAMILTON, S.K., 2011. Abiotic factors controlling the establishment and abundance of the invasive golden mussel Limnoperna fortunei.Biological Invasions, vol. 13, no. 3, pp. 717-729. http://dx.doi.org/10.1007/s10530-010-9862-0.
    » http://dx.doi.org/10.1007/s10530-010-9862-0
  • OLIVEIRA, M.D., PELLEGRIN, L.A., BARRETO, R.R., SANTOS, C.L. and XAVIER, I.G., 2004. Área de ocorrência do Mexilhão Dourado na bacia do Alto Paraguai, entre os anos de 1998 e 2004. Corumbá: Embrapa Pantanal. 19 p. Documentos, vol. 64.
  • OLIVEIRA, M.D., TAKEDA, A.M., BARROS, L.F., BARBOSA, D.S. and RESENDE, E.K., 2006. Invasion by Limnoperna fortunei (Dunker, 1857) (Bivalvia, Mytilidae) of the Pantanal wetland, Brazil. Biological Invasions, vol. 8, no. 1, pp. 97-104. http://dx.doi.org/10.1007/s10530-005-0331-0.
    » http://dx.doi.org/10.1007/s10530-005-0331-0
  • PACE, M.L., FINDLAY, S.E.G. and FISCHER, D., 1998. Effects of an invasive bivalve on the zooplankton community of the Hudson River. Freshwater Biology, vol. 39, no. 1, pp. 103-116. http://dx.doi.org/10.1046/j.1365-2427.1998.00266.x.
    » http://dx.doi.org/10.1046/j.1365-2427.1998.00266.x
  • PAULETO, G.M., VELHO, L.F.M., BUOSI, P.R.B., BRÃO, A.F.S., LANSAC-TÔHA, F.A. and BONECKER, C.C., 2009. Spatial and temporal patterns of ciliate species composition (Protozoa: Ciliophora) in the plankton of the Upper Paraná River floodplain. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 517-527. http://dx.doi.org/10.1590/S1519-69842009000300007. PMid:19738959.
    » http://dx.doi.org/10.1590/S1519-69842009000300007
  • PESTANA, D., OSTRENSKY, A., TSCHÁ, M.K. and BOEGER, W.A., 2010. Prospecção do molusco invasor Limnoperna fortunei (Dunker, 1857) nos principais corpos hídricos do estado do Paraná, Brasil. Papéis Avulsos de Zoologia, vol. 50, no. 34, pp. 553-559. http://dx.doi.org/10.1590/S0031-10492010003400001.
    » http://dx.doi.org/10.1590/S0031-10492010003400001
  • RIBEIRO, M.L., BLANCKAERT, K., ROY, A.G. and SCHLEISS, A.G., 2012. Hydromorphological implications of local tributary widening for river rehabilitation. Water Resources Research, vol. 48, no. 10, pp. 1-19.
  • ROJAS MOLINA, F., PAGGI, J.C. and DEVERCELLI, M., 2010. Zooplanktophagy in the natural diet and selectivity of the invasive moluk Limnoperna fortunei.Biological Invasions, vol. 12, no. 6, pp. 1647-1659. http://dx.doi.org/10.1007/s10530-009-9578-1.
    » http://dx.doi.org/10.1007/s10530-009-9578-1
  • SANTOS, C.P., WÜRDIG, N.L. and MANSUR, M.C.D., 2005. Fases larvais do mexilhão dourado (Dunker) (Mollusca, Bivavia, Mytilidae) na bacia do Guaíba, Rio Grande do Sul, Brasil. Limnoperna fortuneiRevista Brasileira de Zoologia, vol. 22, no. 3, pp. 702-708. http://dx.doi.org/10.1590/S0101-81752005000300029.
    » http://dx.doi.org/10.1590/S0101-81752005000300029
  • SOMMER, U., 1988. Growth and survival strategies of planktonic diatoms. In: C.D. SANDGREN. Growth and reproductive strategies of freshwater phytoplankton. New York: Cambridge University Press, pp. 227-260.
  • SOUZA FILHO, E.E. and STEVAUX, J.C., 1997. Geologia e geomorfologia do complexo rio Baia, Curutuba, Ivinheima. In: A.E.A.M. VAZZPLER, A.A. AGOSTINHO and N.S.A. HAHN. A planície de inundação do alto rio Paraná: aspectos físicos, biológicos e socioeconômicos. Maringá: Editora da Universidade Estadual de Maringá, pp. 3-46.
  • SOUZA FILHO, E.E., 2009. Evaluation of the Upper Paraná River discharge controlled by reservoirs. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 69, no. 2, suppl., pp. 707-716. http://dx.doi.org/10.1590/S1519-69842009000300024. PMid:19738976.
    » http://dx.doi.org/10.1590/S1519-69842009000300024
  • SUN, J. and LIU, D., 2003. Geometric models for calculating cell biovolume and surface area for phytoplankton. Journal of Plankton Research, vol. 25, no. 2, pp. 1331-1346. http://dx.doi.org/10.1093/plankt/fbg096.
    » http://dx.doi.org/10.1093/plankt/fbg096
  • SYLVESTER, F., BOLTOVSKOY, D. and CATALDO, D., 2009. Taxas de clareamento: ritmos e impactos. In: G. DARRIGRAN and C. DAMBORENEA. Introdução a biologia das invasões: o mexilhão dourado na América do Sul: biologia, impacto, prevenção e controle. São Carlos: Cubo, pp. 246.
  • TAKEDA, A.M., MANSUR, M.C.D., FUJITA, D.S. and BIBIAN, J.P.R., 2003. Ocorrência da espécie invasora de mexilhão dourado, Limnoperna . fortunei (Dunker, 1857), em dois pequenos reservatórios próximos a Curitiba, PRActa Biologica Leopondensia, vol. 25, no. 2, pp. 251-254.
  • TER BRAAK, C.J.F., 1986. Canonical correspondence analysis: a new eigenvector technique for multivariate direct gradient analysis. Ecology, vol. 67, no. 5, pp. 1167-1179. http://dx.doi.org/10.2307/1938672.
    » http://dx.doi.org/10.2307/1938672
  • THOMAZ, S.M., ROBERTO, M.C., LANSAC TOHA, F.A., LIMA, F.A. and ESTEVES, F.A., 1992. Características limnológicas de uma estação de amostragem do Alto Rio Paraná e outra do Baixo Rio Ivinhema. Acta Limnologica Brasiliensia, vol. 4, pp. 32-52.
  • THORP, J.H. and CASPER, A.F., 2002. Potential effects on zooplankton from species shifts in planktivorous mussels: a field experiment in the St Lawrence River. Freshwater Biology, vol. 47, no. 1, pp. 107-119. http://dx.doi.org/10.1046/j.1365-2427.2002.00787.x.
    » http://dx.doi.org/10.1046/j.1365-2427.2002.00787.x
  • UTERMÖHL, H., 1958. Zur Vervollkommnung der quantitativen phytoplankton methodike. Mitteilungen - Internationale Vereinigung für Theoretische und Angewandte Limnologie, vol. 9, pp. 1-38.
  • VANDERPLOEG, H.A., LIEBIG, J.R., CARMICHAEL, W.W., AGY, M.A., JOHENGEN, T.H., FAHNENSTIEL, G.F. and NALEPA, T.F., 2001. Zebra mussel (Dreissena polymorphaMicrocystis) selective filtration promoted toxic blooms in Saginaw Bay (Lake Huron) and Lake Erie. Canadian Journal of Fisheries and Aquatic Sciences, vol. 58, no. 6, pp. 1208-1221. http://dx.doi.org/10.1139/f01-066.
    » http://dx.doi.org/10.1139/f01-066
  • WARD, J.V., TOCKNER, K., ARSCOTT, D.B. and CLARET, C., 2002. Riverine landscape diversity. Freshwater Biology, vol. 47, no. 4, pp. 517-539. http://dx.doi.org/10.1046/j.1365-2427.2002.00893.x.
    » http://dx.doi.org/10.1046/j.1365-2427.2002.00893.x

Publication Dates

  • Publication in this collection
    12 Feb 2016
  • Date of issue
    Feb 2016

History

  • Received
    18 Aug 2014
  • Accepted
    25 Nov 2014
Instituto Internacional de Ecologia R. Bento Carlos, 750, 13560-660 São Carlos SP - Brasil, Tel. e Fax: (55 16) 3362-5400 - São Carlos - SP - Brazil
E-mail: bjb@bjb.com.br