Use of diatoms for freshwater quality evaluation （使用硅藻淡水质量评价）.pdf

205 Use of diatoms for freshwater quality evaluation in Portugal. Almeida, S. F. P. Departamento de Biologia, Universidade de Aveiro, 38 10- 193Aveiro, Portugal. E-mail: salmeida@,bio.ua.pt ABSTRACT Diatoms have been extensively used as water quality indicators in Europe for the last two decades. In Portugal, the use of diatoms is not common, except for research at a few universities. Tychoplanktonic diatoms were sampled at 18 sites in the North-Central region of Portugal. Biological water quality using diatom indices was consistent with physical and chemical data. The diatom indices (SPI and CEC) were better than the saprobic indices (SLA and LMI) because the former were more sen- sitive to differences between sampling sites, and were in greater accordance with chemical and physical parameters, especial- ly pH, conductivity and organic content. The aim of this work is to show that some of the diatom indices used in Europe, and particularly, in France, show quite promising results for routine application in Portugal. Keywords: diatoms, indices, freshwater quality RESUMEN En las ultimas dos dicadas, las diatomeas han sido ampliamente utilizadas en Europa como indicadores de la calidad del agua. En Portugal, el uso de las diatomeas no es comzin con excepcidn de la investigacion en las universidades. En 18 estaciones de la region Norte de Portugal se muestrearon las diatomeas ticoplanctdnicas. Los resultados han mostra- do que la calidad bioldgica del agua son consistentes con 10s datosfisicos y quimicos. Los indices de diatomeas (SPIy CEC) dieron mejores resultados que 10s indices saprobios (SLAy LMI)ya que losprimeros fueros mhs sensibles a las diferencias entre estaciones, y estuvieron mas acordes con las variablesfisicas y