Desertification caused by land degradation and overexploitation of natural resources is threatening large parts of eastern and southern Mediterranean. The actual state of desertification sensitivity in Lebanon was spa...Desertification caused by land degradation and overexploitation of natural resources is threatening large parts of eastern and southern Mediterranean. The actual state of desertification sensitivity in Lebanon was spatially assessed using site specific environmental bio-physical indicators, demographic pressure and socioeconomic conditions. Bio-physical assessment included the aridity index derived from integrated assessment of the historical data for 48 climatic stations spread throughout the country, the new detailed soil map at 1：50,000 scale, and the updated land cover/use map at 1：20,000 derived from IKONOS 2005. The methodology also included livelihood conditions and poverty at local administrative ＂Caza＂ level. Results showed the integrated impact of local climate, soil and vegetation quality and socioeconomic conditions on sensitivity to desertification. A total of 78% of the territories have low and very low climate quality index preconditioning the sensitivity to desertification. Fourteen Cazas out of 26 in total, representing more than 66% of the country, have low socioeconomic satisfaction index. Furthermore, negative trends are alleviated by good quality relict soils and vegetation cover. The actual extent of desertification covers 40.48% of the national territory, much of which occurs under semi-arid climate, moderate or low soil and vegetation quality and poor living conditions. The outcome of this research adjusted the previous coarse estimates of desertification prone areas at the national level. Results allow for realistic, policy oriented local assessment for responsive land use planning and proactive sustainable, national and local land management in the context of the national action plan to combat desertification.展开更多
The evaluation of groundwater quality under agricultural land use and fertilizers’application was assessed by the physio-chemical parameters(20 parameters)of the springs of Ras El-Ain and 24 wells upstream.This study...The evaluation of groundwater quality under agricultural land use and fertilizers’application was assessed by the physio-chemical parameters(20 parameters)of the springs of Ras El-Ain and 24 wells upstream.This study allows the investigation of chemical contamination reaching Ras El-Ain springs,an ecologically-rich site and part of Tyre Coast Nature Reserve,in addition to diverse well sites of mainly agricultural uses,located in the lower sub-catchment area of Ras El-Ain.The results of physio-chemical analyses show that their pH values are all alkaline,probably due to their rock exposure to Eocene Limestone(E);TDS and EC values are acceptable in all sites.17 of the 26 sites are contaminated with Nitrite(NO_(2)^(−)),15 of which are wells and the other two are Ras El-Ain springs(sites 24&25);all contaminated sites by(NO_(2)^(−))exceed only the drinking water guideline by WHO,which entails restricted agricultural use for irrigation,and prohibiting water distribution for drinking and domestic purposes.Only sites(1)and(23)show very high Nitrate(3 NO−)content,with site(1)exceeding both limits for drinking and irrigation water guidelines set by the WHO and FAO respectively,while site(23)exceeds only the limit for drinking water.The origin of contamination with Nitrate and Nitrite is agricultural fertilizers.Sites(20)and(21)are contaminated with Fluoride(F^(−)),exceeding only the drinking water limit.15 sites(excluding Ras El-Ain springs)are contaminated with Bromide(Br^(−)),exceeding only the drinking water limit.No other ions or heavy metals’contamination were detected in the study sites.PCA statistical analysis shows that sites(1),(12),(20)and(22)are the most contaminated sites mainly with Nitrite,Nitrate,Fluoride and Bromide,primarily caused by over application of agrochemicals,proving the negative effect of unregulated agricultural land-use on groundwater quality.展开更多
文摘Desertification caused by land degradation and overexploitation of natural resources is threatening large parts of eastern and southern Mediterranean. The actual state of desertification sensitivity in Lebanon was spatially assessed using site specific environmental bio-physical indicators, demographic pressure and socioeconomic conditions. Bio-physical assessment included the aridity index derived from integrated assessment of the historical data for 48 climatic stations spread throughout the country, the new detailed soil map at 1：50,000 scale, and the updated land cover/use map at 1：20,000 derived from IKONOS 2005. The methodology also included livelihood conditions and poverty at local administrative ＂Caza＂ level. Results showed the integrated impact of local climate, soil and vegetation quality and socioeconomic conditions on sensitivity to desertification. A total of 78% of the territories have low and very low climate quality index preconditioning the sensitivity to desertification. Fourteen Cazas out of 26 in total, representing more than 66% of the country, have low socioeconomic satisfaction index. Furthermore, negative trends are alleviated by good quality relict soils and vegetation cover. The actual extent of desertification covers 40.48% of the national territory, much of which occurs under semi-arid climate, moderate or low soil and vegetation quality and poor living conditions. The outcome of this research adjusted the previous coarse estimates of desertification prone areas at the national level. Results allow for realistic, policy oriented local assessment for responsive land use planning and proactive sustainable, national and local land management in the context of the national action plan to combat desertification.
文摘The evaluation of groundwater quality under agricultural land use and fertilizers’application was assessed by the physio-chemical parameters(20 parameters)of the springs of Ras El-Ain and 24 wells upstream.This study allows the investigation of chemical contamination reaching Ras El-Ain springs,an ecologically-rich site and part of Tyre Coast Nature Reserve,in addition to diverse well sites of mainly agricultural uses,located in the lower sub-catchment area of Ras El-Ain.The results of physio-chemical analyses show that their pH values are all alkaline,probably due to their rock exposure to Eocene Limestone(E);TDS and EC values are acceptable in all sites.17 of the 26 sites are contaminated with Nitrite(NO_(2)^(−)),15 of which are wells and the other two are Ras El-Ain springs(sites 24&25);all contaminated sites by(NO_(2)^(−))exceed only the drinking water guideline by WHO,which entails restricted agricultural use for irrigation,and prohibiting water distribution for drinking and domestic purposes.Only sites(1)and(23)show very high Nitrate(3 NO−)content,with site(1)exceeding both limits for drinking and irrigation water guidelines set by the WHO and FAO respectively,while site(23)exceeds only the limit for drinking water.The origin of contamination with Nitrate and Nitrite is agricultural fertilizers.Sites(20)and(21)are contaminated with Fluoride(F^(−)),exceeding only the drinking water limit.15 sites(excluding Ras El-Ain springs)are contaminated with Bromide(Br^(−)),exceeding only the drinking water limit.No other ions or heavy metals’contamination were detected in the study sites.PCA statistical analysis shows that sites(1),(12),(20)and(22)are the most contaminated sites mainly with Nitrite,Nitrate,Fluoride and Bromide,primarily caused by over application of agrochemicals,proving the negative effect of unregulated agricultural land-use on groundwater quality.
