Seasonal Variation of Major Nutrients and Selected Physicochemical Parameters in Soil from Small Scale Tea Farms Along Sulal River, Bureti Sub County, Kericho County, Kenya

Abstract

A study was conducted to evaluate seasonal variations of major nutrients and selected physicochemical parameters in soils. The soil samples were collected from small scale tea farms adjusted to Sulal River in Kenya before and after the application of nitrogen, phosphorous, potassium (NPK) fertilizer in order to ascertain the farmer’s role in controlling the movement of chemical nutrients into the river. Ten soil samples were collected from selected ten different tea farms and analyzed for pH, percentage moisture content (MC), electrical conductivity (EC), nitrate-nitrogen (NO₃-N) and phosphorous (PO₃-P) were analysed calorimetrically using Salicylic acid and Olsen methods respectively while potassium by flame photometer. Standard methods, IBM SPSS 20 was used for data analysis. The results during dry season revealed that the range of pH was 4.07±0.03 - 4.98±0.08, MC was 12.58±0.52 - 21.76±0.52 %, EC was 85±7.85- 245±6.50 µS/cm, NO₃-N was 0.14±0.03 - 0.87±0.01mg/L, PO₃-P was 0.06±0.03 - 0.32±0.04mg/L and K

was 0.98±0.36- 2.05±0.28 mg/L while during rainy season, the range of pH was 4.18±0.03- 4.80±0.12, MC was 30.92±0.56- 37.36±0.45 %, EC was 216±3.72- 289±7.25µS/cm, NO₃-N was

0.33±0.04- 0.90±0.07mg/L, PO₃-P was 0.08±0.07– 0.68±0.04mg/L and K was 1.65±0.35-

3.48±0.15 mg/L Seasonal variation revealed significant differences in all parameters except NO₃-N and PO₃-P. The correlation study indicated that moisture content was significantly correlated to electrical conductivity, PO₃-P and K while electrical conductivity and PO₃-P were both significantly correlated to K. The soils in both seasons had low major nutrients contents. Stringent legislation on management of soils along the rivers is recommended.