An understanding of the long-term changes in the nitrate and microbial contamination pattern of the groundwater of Sidi Bouzid （Centre West of Tunisia） is critical to conservation of drinking water in rural areas su...An understanding of the long-term changes in the nitrate and microbial contamination pattern of the groundwater of Sidi Bouzid （Centre West of Tunisia） is critical to conservation of drinking water in rural areas supporting mixed land-use activities such as cropping, livestock farming, and residence. The phreatic aquifer was revealed polluted by domestic disposals of the wastewaters in the urban zone. The average nitrate concentration in the groundwater of the east of the mioplioquaternary aquifer of Saddaguia （Sidi Bouzid） rose from 50 mg NO3- during 1996 to over 100 mg in 2003, which represents an increase of some 10 mg per year. Nitrate groundwater pollution during the period 1996-2003 was the result of the abusive use of fertilizers.In the cultivated zone, we must reduce the effects of the excessive use of the nitrogen fertilizers on the basis of monitoring soil once a year, managing water resources, rationalizing the use of the chemical substances. In urban zones, most of lost wells located in the perimeter reveal the gravity of the state of the aquifer. This last is organically polluted and requires an immediate action for the generalization of the purification network. We need to take into account the reality of under soil in all future planning＇s and arrangements. A scheme of sanitation seems necessary before all plans of arrangement. The extension of the sewer network must give the priority to the most vulnerable zones.展开更多
Nitrate is one of the problematic and wide spread contaminations. Indiscriminate disposition of human and animal wastes in Nigeria especially in urban region, and lack of proper environmental sanitation geared the nee...Nitrate is one of the problematic and wide spread contaminations. Indiscriminate disposition of human and animal wastes in Nigeria especially in urban region, and lack of proper environmental sanitation geared the need for the monitoring of groundwater contamination. This research work monitored the concentration of nitrate and nitrate-nitrogen in portable water from wells in Odo Ado, Ado-Ekiti, Ekiti State, and examined the relationship between this concentration and the well depth as well as its nature （ringing）. The results showed that out of 20 water wells sampled, 50% of samples contain high level of nitrate with the highest having concentration of 140 mg/L and least 49 mg/L while the remaining has acceptable concentration ranging between 3.5 mg/L and 35 mg/L with most ringed wells. The mean concentration of nitrates is 48.06 mg/L and the nitrate-nitrogen is 10.85 mg/L. The statistical correlation between the concentrations and depth showed that there is a significant difference between their means at 95% confidence using T-test. Out of ringed wells, five have high concentration and eight have low concentrations while two of the wells （not ringed） fall below the acceptable limit （EPA） which indicates that there are other factors such as closeness to the point source and soil texture which were not considered in this work.展开更多
文摘An understanding of the long-term changes in the nitrate and microbial contamination pattern of the groundwater of Sidi Bouzid （Centre West of Tunisia） is critical to conservation of drinking water in rural areas supporting mixed land-use activities such as cropping, livestock farming, and residence. The phreatic aquifer was revealed polluted by domestic disposals of the wastewaters in the urban zone. The average nitrate concentration in the groundwater of the east of the mioplioquaternary aquifer of Saddaguia （Sidi Bouzid） rose from 50 mg NO3- during 1996 to over 100 mg in 2003, which represents an increase of some 10 mg per year. Nitrate groundwater pollution during the period 1996-2003 was the result of the abusive use of fertilizers.In the cultivated zone, we must reduce the effects of the excessive use of the nitrogen fertilizers on the basis of monitoring soil once a year, managing water resources, rationalizing the use of the chemical substances. In urban zones, most of lost wells located in the perimeter reveal the gravity of the state of the aquifer. This last is organically polluted and requires an immediate action for the generalization of the purification network. We need to take into account the reality of under soil in all future planning＇s and arrangements. A scheme of sanitation seems necessary before all plans of arrangement. The extension of the sewer network must give the priority to the most vulnerable zones.
文摘Nitrate is one of the problematic and wide spread contaminations. Indiscriminate disposition of human and animal wastes in Nigeria especially in urban region, and lack of proper environmental sanitation geared the need for the monitoring of groundwater contamination. This research work monitored the concentration of nitrate and nitrate-nitrogen in portable water from wells in Odo Ado, Ado-Ekiti, Ekiti State, and examined the relationship between this concentration and the well depth as well as its nature （ringing）. The results showed that out of 20 water wells sampled, 50% of samples contain high level of nitrate with the highest having concentration of 140 mg/L and least 49 mg/L while the remaining has acceptable concentration ranging between 3.5 mg/L and 35 mg/L with most ringed wells. The mean concentration of nitrates is 48.06 mg/L and the nitrate-nitrogen is 10.85 mg/L. The statistical correlation between the concentrations and depth showed that there is a significant difference between their means at 95% confidence using T-test. Out of ringed wells, five have high concentration and eight have low concentrations while two of the wells （not ringed） fall below the acceptable limit （EPA） which indicates that there are other factors such as closeness to the point source and soil texture which were not considered in this work.
