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Stylianos Liodakis Charalampos Michalopoulos Elpida Efthymiou Georgios Katsigiannis 《Water, air, and soil pollution》2012,223(1):169-179
One of the main environmental impacts of concentrated animal feeding operations is the soil degradation in vicinity with the
livestock breeding facilities due to substances such as ammonia emitted from the various stages of the process. Owing to the
high temperatures of the Mediterranean ecosystems, the evolution of gasses is more extensive and the soil degradation is consequently
more severe than those obtained in northern Europe. In this research, the soil degradation effects of a large meat-producing,
processing, and packaging unit have been investigated. The investigated intensive hog farming operation (IHFO) is located
at a limestone soil coastal area with sea to the north and hills to the south. Soil samples of the upper mineral soil were
taken in various distances and directions from the IHFO boundaries. Thirteen experimental cycles were carried out in the duration
of 1.5 years starting in March 2009 until October 2010. The soil samples were analyzed on pH and electrical conductivity (EC)
values as well as NH4
+ and NO3
− concentrations. Significantly higher concentrations of the two nitrogen forms were observed on samples at increasing proximity
downwind from the farm (south). Southern soil average NH4
+ and NO3
− concentrations ranged between 0.4–118 μg NH4
+-N g−1 soil and 6.1–88.4 μg NO3
−-N g−1 soil, respectively. The variation of emitted gasses depositions was clearly reflected in the average pH and EC values. Average
pH and EC values downwind from IHFO boundaries varied between 7.1–8.2 and 140–268 μS/cm, respectively. 相似文献
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Konstantina Tyrovola Elpida Peroulaki Nikolaos P. Nikolaidis 《European Journal of Soil Biology》2007,43(5-6):356
Ground waters in geothermal regions contain arsenic concentrations that exceed the recommended drinking water standards. In addition, when these regions have agricultural activities, the waters also contain high levels of nitrates and phosphates. These contaminants can be removed from the water with the use of filters containing zero valent iron (ZVI). The objective of this study was to model the removal of arsenate (As(V)) and arsenite (As(III)) by ZVI and to model the effect of competing ions (phosphate and nitrate) on arsenate removal. Arsenic immobilization by ZVI columns was simulated by the HM-1D chemical transport and speciation model and an one-dimensional analytical solution model. Laboratory column studies were conducted in order to obtain representative experimental data for simulation with both models. Arsenic speciation and the presence of competing ions greatly affect arsenic removal by ZVI. Most arsenic is precipitated/co-precipitated on ZVI and on the corrosion products formed on ZVI. The simulations suggested that As(V) process parameters are higher than the As(III) parameters and that they are affected by the presence of nitrates and phosphates in the system. Such models can be used to design treatment units by incorporating the impact of nitrates and phosphates in the removal of arsenic by ZVI as well as the impact of temperature on the process. 相似文献
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