[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigatio...[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.展开更多
The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditi...The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditional irrigation canals since farmers are encouraged to turn to drip irrigation and overhead irrigation gradually. Given this, we would like to argue that traditional irrigation canals need to be reexamined. Such canals are not only built aquatic infrastructure, they are also the product of a culture and social relationship with water in the Mediterranean region. Canals form a complex system which is driven by environmental, economic and social factors. Our sociological and environmental research in Provence （and around the Durance basin more specifically） points up how the very dense territorial network of gravity-fed canals is useful in water management, as well as in other shared uses over the long-term. The findings underscore the positive environmental role played by these historical and anthropogenic constructions. They contribute to refilling the aquifer and also act as a valuable environmental good and service （e.g., run-off regulation, biodiversity, landscape, recreation, etc.）. Further, several local actors have underscored their role as part of an intangible cultural heritage and as important for the area＇s economic and social development. Such canals play a central role in sustainable development since beyond their productive role in agriculture, they play a social role （new uses） and an ecological role （as reservoirs for biodiversity and ecological corridors）.展开更多
The effective and efficient management of agricultural water use is crucial to enhance agricultural production to meet the demand of a rapidly growing population. The performance assessment studies are successfully us...The effective and efficient management of agricultural water use is crucial to enhance agricultural production to meet the demand of a rapidly growing population. The performance assessment studies are successfully used to describe the irrigation problems and provide remedial measures. In this study, the performance assessment of the twin main canals of the Gezira Scheme were examined and evaluated using a set of performance indicators. The analysis was made using 3 Landsat and 8 Modis data of 2001-2002, and results showed that the seasonal average values of water productivity, relative water supply, overall consumed ratio, depleted fraction and relative evapotranspiration were respectively 0.47, 0.72, 1.41, 0.75 and 0.57 kg·m^-3 for Gezira main canal, whereas the values for Managil main canal were 0.43, 0.54, 1.68, 0.71 and 0.50 kg·m^-3, respectively. The monthly average values of crop water deficit for Gezira and Managil were respectively 71 and 78 mm-month^-1. Considering the spatial variation in some indicators, the irrigation uniformity is deemed as poor according to Molden and Gates （1990）. The analysis also showed that the gap between water demand and supply during winter season was glaringly high （46%）.展开更多
Since 2000 Chihuahua City has distribution system Waste Water Treatment （WTR）, watering city＇s green areas. The need to cover the growing demand for drinking water has encouraged the use of non-potable water where ...Since 2000 Chihuahua City has distribution system Waste Water Treatment （WTR）, watering city＇s green areas. The need to cover the growing demand for drinking water has encouraged the use of non-potable water where water quality is not an issue despite being used by 10 years ago, it is not known whether nitrogen compounds derived from WTR pose risks to the environment and public health. Therefore, in order to minimize health and environmental risks, this is needed to assess the impact and policy support for water use. The aim of this study is to determine the constitution and the concentration of nitrogen compounds through selection and characterization of park＇s representative. It＇s divided into physical properties and main parameters that affect nitrogen transformations. It was determined that sand was material that allowed more favorable oxidation and reduction of nitrate in soil and atmosphere, opposite of the clay, When used WTR, nitrates, nitrites and ammonia nitrogen were identified in the subsurface and NOx and N20 were identified in the atmosphere. When drinking water was used, none of these compounds was found. However, it was determined that despite having high concentrations of nitrates, the WTR was within the limits allowed by the Mexican standard for the use of WTR in public places.展开更多
基金Supported by National Science and Technology Project of "the Eleventh Five-year Plan" of China (2006BAD17B07)Doctoral Fund of Shandong Academy of Agricultural Sciences (2006YBS015)~~
文摘[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.
文摘The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditional irrigation canals since farmers are encouraged to turn to drip irrigation and overhead irrigation gradually. Given this, we would like to argue that traditional irrigation canals need to be reexamined. Such canals are not only built aquatic infrastructure, they are also the product of a culture and social relationship with water in the Mediterranean region. Canals form a complex system which is driven by environmental, economic and social factors. Our sociological and environmental research in Provence （and around the Durance basin more specifically） points up how the very dense territorial network of gravity-fed canals is useful in water management, as well as in other shared uses over the long-term. The findings underscore the positive environmental role played by these historical and anthropogenic constructions. They contribute to refilling the aquifer and also act as a valuable environmental good and service （e.g., run-off regulation, biodiversity, landscape, recreation, etc.）. Further, several local actors have underscored their role as part of an intangible cultural heritage and as important for the area＇s economic and social development. Such canals play a central role in sustainable development since beyond their productive role in agriculture, they play a social role （new uses） and an ecological role （as reservoirs for biodiversity and ecological corridors）.
文摘The effective and efficient management of agricultural water use is crucial to enhance agricultural production to meet the demand of a rapidly growing population. The performance assessment studies are successfully used to describe the irrigation problems and provide remedial measures. In this study, the performance assessment of the twin main canals of the Gezira Scheme were examined and evaluated using a set of performance indicators. The analysis was made using 3 Landsat and 8 Modis data of 2001-2002, and results showed that the seasonal average values of water productivity, relative water supply, overall consumed ratio, depleted fraction and relative evapotranspiration were respectively 0.47, 0.72, 1.41, 0.75 and 0.57 kg·m^-3 for Gezira main canal, whereas the values for Managil main canal were 0.43, 0.54, 1.68, 0.71 and 0.50 kg·m^-3, respectively. The monthly average values of crop water deficit for Gezira and Managil were respectively 71 and 78 mm-month^-1. Considering the spatial variation in some indicators, the irrigation uniformity is deemed as poor according to Molden and Gates （1990）. The analysis also showed that the gap between water demand and supply during winter season was glaringly high （46%）.
文摘Since 2000 Chihuahua City has distribution system Waste Water Treatment （WTR）, watering city＇s green areas. The need to cover the growing demand for drinking water has encouraged the use of non-potable water where water quality is not an issue despite being used by 10 years ago, it is not known whether nitrogen compounds derived from WTR pose risks to the environment and public health. Therefore, in order to minimize health and environmental risks, this is needed to assess the impact and policy support for water use. The aim of this study is to determine the constitution and the concentration of nitrogen compounds through selection and characterization of park＇s representative. It＇s divided into physical properties and main parameters that affect nitrogen transformations. It was determined that sand was material that allowed more favorable oxidation and reduction of nitrate in soil and atmosphere, opposite of the clay, When used WTR, nitrates, nitrites and ammonia nitrogen were identified in the subsurface and NOx and N20 were identified in the atmosphere. When drinking water was used, none of these compounds was found. However, it was determined that despite having high concentrations of nitrates, the WTR was within the limits allowed by the Mexican standard for the use of WTR in public places.
