info:eu-repo/semantics/article
Use of diatoms (Bacillariophyceae) for water quality assessment in two tropical streams in Costa Rica
Use of diatoms (Bacillariophyceae) for water quality assessment in two tropical streams in Costa Rica
Autor
Michels, Astrid
Institución
Resumen
Effects of pig farm sewage water in two tropical streams were studied for a five month period considering physical chemical and biological parameters. The method of Lange-Bertalot and the method of Steinberg & Schiefele, both based on benthic diatoms, were applied for the biological water assessment. Results were compared to indices calculated from the physical chemical variables (oxygen, nitrate, nitrite, ammonia and phosphate). According to both methods the percentages of the diatom species groups reflected the increase: and subsequent decrease of pollution. However, in both methods, species groups did often not fit the criteria of the classification schemes for calculation of water quality. The sources of these problems were discussed in this paper. More information on the ecological requirements of diatoms in tropical areas is needed to design procedures for water quality assessment for tropical streams. Se estudió el efecto de aguas negras de porquerizas en dos ríos tropicales considerando parametros fisico-químicos y biológicos. Se aplicaron los metodos de Lange Bertalot y Steinberg & Schiefele. utilizando las diatomeas epiliticas, para el monitoreo biológico. Los resultados se compararon con índices calculados de los paramerros fisico-químicos (oxígeno, nitrato, nitrito, amonio, fosfato). Grupos de especies con la misma tolerancia a la contaminación reflejaron el aumento y la siguente disminución de contaminación y por lo tanto proveen información util con respecto a la calidad del agua. Sin embargo, las diatomeas no correspondían a los criterios de clasificación y por lo tanto la indicación de la calidad del agua fue insuficiente. Se necesitarán mas estudios sobre la autecología de las diatomeas en regiones tropicales para hacer los métodos de monitoreo de calidad del agua mas apropiados para ríos de esta zona.