Assessment of Macronutrients in a Tropical Rainforest Stream, Southern Nigeria

Abstract

The macronutrients of water samples from Ogbei Stream in Nkpologwu, Aguata Local Government Area of Anambra State, Nigeria was investigated between May 2008 and April 2009. Water samples were collected fortnightly using sterilized plastic containers fresh from factory. The pattern of cationic dominance in the study was Ca>Mg>Na>Fe. The calcium concentration was highest in station 4 (7.54±0.82 mg/l). The highest and lowest mean values of magnesium, iron and sodium occurred in station 6 (6.16±6.40 mg/l, range 0.60 – 7.60 mg/l) and lowest in station 5 (5.97 ± 0.42 mg/l), range 0.70 – 8.30 mg/l), station 2 (1.46±0.34 mg/l, 0.10 – 4.60 mg/l) and station 6 (1.27±0.32 mg/l, range 0.00 – 4.30 mg/l), and station 1 (2.13±0.78 mg/l, range 0.30 – 12.90 mg/l) and station 3 (1.99±0.73 mg/l, range 0.30 – 12.90 mg/l) respectively. No significant difference (p>0.05) existed between the various mean values recorded for the different parameters at the study stations. The highest mean calcium concentration value of 12.42±0.16 mg/l recorded in March was significantly different (p<0.05) from the mean values of all other months. The mean magnesium concentration was maximum (7.56±0.08 mg/l) in February. The June and September mean values for iron differed significantly (p<0.05) from each other and from the values of all other months. Sodium was highest in June (4.48±1.21 mg/l) and lowest (0.35±0.02 mg/l) in November. T-test showed that calcium, magnesium and iron mean values recorded in the dry season and rainy season were significantly different (p<0.05). There was no significant difference (p>0.05) in the sodium mean values obtained for dry season and rainy season.