Environmental Implication of Thermal Radiation on the Physiochemical Properties of Soil around Gas Flare Sites in the Niger Delta Region of Nigeria

Abstract

The effect of thermal radiation on the Physiochemical properties of soil around gas flare site in the Niger Delta region was assessed in Emuoha Local Government Area of River State, Nigeria, for a period of twelve months. Radiation profile was determined at different times (hours) – 6, 10, 14, 18 and 22, in the four seasons (early dry, early wet, late dry and late wet) of the year. Soil samples were taken at different depths (cm) (0-15 and 15-30) for physicochemical attributes at different distances (m) (0-150, 150-300, 300-450, 450-600 and 1000 -2000) from the flare site and thermal radiation was also determined at the respective distances. Results of effect of time and seasonal variations on radiation profile showed that environmental temperature (oC) ranged from 29.2 ± 0.3 at 22 hours of early wet season to 33.0 ± 0.4 at 14 hours of late dry season; radiation temperature ranged from 35.4 ± 1.2 at 22 hours of late wet season to 42.0 ± 1.4 at 14 hours of late dry season, while thermal radiation (w/m2) ranged from 490.83 ± 7.7 at 22 hours of late wet season to 535.69 ± 9.69 at 14 hours of late dry season. Results of effect of flare distance on physicochemical properties of soil showed that as the distance (m) from flare site increases from 0 – 150 to 1000 – 2000, the radiation intensity (w/m2) decreases from 603.84 ± 5.7 – 428.83 ± 0.75, and values of pH, OC, N, P,  and exchangeable cations - K+, Na+, Ca2+, Mg2+ increases in the range {pH (4.94 ± 0.02 – 5.50 ± 0.00), OC (1.09 ± 0.01 – 2.05 ± 0.00), N (0.07 ±0.01 – 0.09 ± 0.00), P (10.90 ± 0.03 – 12.10 ± 5.19), K+ (0.28 ± 0.01 – 1.86 ± 0.01), Na+ (0.48 ± 0.00 – 1.04 ± 0.00), Ca2+ (1.65 ± 0.01 – 2.85 ± 0.00), Mg2+ (0.73 ± 0.01 – 1.24 ± 0.01)}, These values seemed not to be affected by the thermal radiation and flare distance , oil and grease and THC decreases in the range 203.30 ± 0.88 – 61.33 ± 0.33 and 352.90 ± 2.08 – 10.04 ± 0.04 respectively. Similar trend was observed with soil samples taken at 15-30cm depth. Statistical analysis showed there is significant difference (p<0.001) in soil attributes as distance from flare distance increases. Further studies should be carried out to investigate the relationship between soil around flare site and crop performance on different agro-ecological zone of Rivers State.