1. Post‐Graduate Program in Ecology, Bioscience Inst., Univ. Federal do Rio Grande do Norte Natal Brazil
2. Marine Ecology Laboratory, Dept of Oceanography and Limnology, Univ. Federal do Rio Grande do Norte Natal RN Brazil
3. Dept of Civil Engeneering, Univ. Federal do Rio Grande do Norte Natal Brazil
4. Laboratorio de Limnología, INIBIOMA (CONICET‐UNCo) Río Negro Argentina