ABSTRACT:

This study examined the effect of human activities on the Lokpoi stream in Yakurr catchment area, Cross River State, Nigeria. Thirteen (13) water quality parameters (pH, DO, specific conductivity, BOD5, NO3, NH4, PO4, SO4, Fe, Zn, Mn, total coliform and feacal coliform) were determined from water samples at five (5) stations along the Lokpoi stream. Sampling was done once a week for a period of 12 weeks (three months), using the methods described by APHA (1984). The results showed that the pH values ranged from 6.69 to 6.89 for station A(area under forest reserve); 6.72 to 6.79 for station B(area under community forest); 6.30 to 6.49 for station C (area under agricultural land use); 6.28 to 6.31 for station C(area under residential land use) and 6.26 to 6.30 for station E(area under recreational land use). Similarly, dissolved oxygen ranged from 5.80 to 6.15 for station A; 3.40 to 3.90 for station B; 3.20 to 3.60 for station C; 3.40 to 3.70 for station D and 3.24 to 3.65 for station E. Furthermore, total coliform count ranged from 0.00 to 2.00 for station A; none for station B; 0.00 to 2.00 for station C; 4.00 to 7.00 for station D and 6.00 to 10.00 for station E. Also, feacal coliform was not available in stations A and B but ranged from 0.00 to 1.00 in station C; 2.00 to 4.00 in station D and 3.00 to 4.00 in station E. The analysis of variance revealed that significant difference existed in water quality parameters as sampled along the various human activity zones. Also, significant differences existed between the water quality parameters and the WHO standards for domestic purposes. The study concluded that the stream has been polluted as a result of the human activities along the buffer zone. It is recommended that human activity along the buffer zone of the stream should be minimized to reduce further deterioration of the water body.