Estimation of River Utroya Ecological State in Intensive Organic Pollution Area Using Plankton Communities ’ Characteristics (Pskov Region). ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, [S. l.], v. 3, p. 62–64, 2015. DOI: 10.17770/etr2013vol3.882. Disponível em: https://archive-journals.rtu.lv/etr/article/view/3901.. Acesso em: 11 mar. 2026.