Fig. 1From: Influence of the interaction of calcium carbonate particles with surfactants on the degree of water pollution in small riversDynamics of ammonium (a) and nitrite (b) ion concentrations in the Nistru River (Spataru et al. 2015). 1—Nistru River, Varancau village. 2—Nistru River, Varancau village + CaCO3. 3—Cunicea village, small river. 4—Cunicea village, small river + CaCO3 Back to article page