Reference values of the physico-chemical parameters of the water streams of Tai national Park (Côte d'Ivoire)

Abstract

water in West Africa is based on European standards which are inadequate. This study was carried out in order to determine the threshold values of physico-chemical parameters for the monitoring of water quality in tropical forest rivers in West Africa. Thus, physico-chemical parameters were measured in 324 surface waters collected in three typical rivers of Taï National Park (Côte d’Ivoire) from May 2016 to April 2017. Subsequently, the sampling stations were categorised as natural, transitional and impacted based on a principal component analysis (PCA). The results confirmed the typology of sampling stations reported in the literature. Based on best professional judgment (BPJ) and trisection methods, the reference values for Tai National Park are Temperature: 25.10-25.33°C; pH: 6.86 - 7.04; DO: 6.33 - 6.40 mg/L; EC: 37. 13 - 38.20 μS/cm; TSD: 27.50 - 29.03 mg/L; NO^2- : 0.005 - 0.009 mg/L; NO^3- : 0.450 - 0.625 mg/L; PO₄^2- : 0.053 - 0.054 mg/L; TP: 0.123 - 0.134 mg/L; FCl: 0.03 - 0.04 mg/L; TCl: 0.04 - 0.05 mg/L. These data could be used as threshold values for monitoring rivers and rainforest wetlands in West Africa.