This research was conducted throughout the years 2008-2010 to study the influence of irrigation water quality on oil quality of ＂Nabali Muhassan＂ olive trees. Reclaimed municipal wastewater and fresh water were used...This research was conducted throughout the years 2008-2010 to study the influence of irrigation water quality on oil quality of ＂Nabali Muhassan＂ olive trees. Reclaimed municipal wastewater and fresh water were used twice a week using drip irrigation system. Rainfed olive trees of the same farm were taken as control. No significant differences were observed between rainfed, fresh water and reclaimed wastewater treatments in terms of acidity, peroxide values and UV absorbance of the extracted olive oil. Heavy metals and microbiological pathogens were not detected in all tested olive oil samples. Oleic acid was significantly higher in olive oil obtained from rainfed trees than irrigated trees. Linoleic acid content was significantly higher in reclaimed wastewater irrigated trees than the rainfed trees. Total polyphenol contents were significantly higher in oil obtained from rainfed olive trees than oil obtained from the irrigated olive trees. Results of organoleptic analysis showed no significant differences in the fruity attribute within treatments, while the bitter and pungent attributes were higher in olive oil obtained from rainfed trees as compared to that obtained from irrigated trees. No negative attributes were observed in oil obtained from the irrigated or rainfed trees and they were all classified as extra virgin grade.展开更多
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
文摘This research was conducted throughout the years 2008-2010 to study the influence of irrigation water quality on oil quality of ＂Nabali Muhassan＂ olive trees. Reclaimed municipal wastewater and fresh water were used twice a week using drip irrigation system. Rainfed olive trees of the same farm were taken as control. No significant differences were observed between rainfed, fresh water and reclaimed wastewater treatments in terms of acidity, peroxide values and UV absorbance of the extracted olive oil. Heavy metals and microbiological pathogens were not detected in all tested olive oil samples. Oleic acid was significantly higher in olive oil obtained from rainfed trees than irrigated trees. Linoleic acid content was significantly higher in reclaimed wastewater irrigated trees than the rainfed trees. Total polyphenol contents were significantly higher in oil obtained from rainfed olive trees than oil obtained from the irrigated olive trees. Results of organoleptic analysis showed no significant differences in the fruity attribute within treatments, while the bitter and pungent attributes were higher in olive oil obtained from rainfed trees as compared to that obtained from irrigated trees. No negative attributes were observed in oil obtained from the irrigated or rainfed trees and they were all classified as extra virgin grade.
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.
