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861.
The United Kingdom Institute of Hydrology (UKIH) smoothed minima baseflow separation method originally developed for the daily flow data of perennial streams and adopted for intermittent streams is presented. The adopted method (AdUKIH) is the generalized version of the UKIH and hence applicable not only to intermittent streams but also to perennial streams. The AdUKIH method is applied on three daily streamflow gauging stations from the European part of Turkey, the Thrace region. The AdUKIH enables one to change the parameter 0·9 in the UKIH method and also introduces different block sizes, which is limited to five days in the original UKIH method. The AdUKIH method is considered a useful tool in helping practitioners and researchers to separate continuous baseflow from the daily flow in perennial and intermittent streams. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
862.
The aim of this work is to study the removal of fluoride from brackish polluted water using electrodialysis. The influence of several parameters such as flow rate, initial feed concentration, co‐existing ions, and initial pH on process efficiency were studied. This efficiency is evaluated by the removal rate, demineralization rate, and power consumption. The defluoridation process showed to be independent of pH of feed solution. Although the remained studied parameters plays a significant role on the defluoridation efficiency and mainly on the specific power consumption. The defluoridation of a contaminated real water sample was investigated so as to improve the efficiency of the process. The fluoride concentration could be reduced from 2.9 to 0.4 mg L−1 which was lower than World Health Organization (WHO) standard (1.5 mg L−1). Moreover the concentrations of different species in the obtained treated water are below the amounts recommended by WHO for drinking water. 相似文献
863.
The effect of varying parameters such as dye concentration, adsorbent dose, pH and temperature on the adsorption capacity of Pleurotus ostreatus is investigated. The commonly available white rot fungus Pleurotus ostreatus is investigated as a viable biomaterial for the biological treatment of synthetic basic methylene blue effluents. The results obtained from the batch experiments reveal the ability of the fungus to remove methylene blue. The performance is dependent on the dye concentration, pH, and fungal biomass. The equilibrium and kinetics of adsorption are investigated and the Langmuir equation is used to fit the equilibrium isotherm. The adsorption isotherm of methylene blue follows only the Langmuir model with a correlation coefficient of ca. 0.96–0.99. The maximum adsorption capacity is ca. 70 mg of dye per g of dry fungus at pH 11, 70 mg L–1 dye, and 0.1 g L–1 fungus concentration, respectively. This study demonstrates that the fungus could be used as an effective biosorbent for the treatment of dye‐containing wastewater streams. 相似文献
864.
不同土壤水分条件和气温对沙枣树出胶的影响 总被引:4,自引:1,他引:3
对沙枣树的出胶进行了不同土壤水环境条件下的比较。结果表明,湿润林带的出胶率低,但出胶量高,干旱林带则相反,是出胶率高而出胶量低。沙枣树的出胶应该是自身生理活性作用和受害反应的结果。同时还发现沙枣树的出胶率和出胶量都随气温的增加而明显增加。指出出胶率高是病虫害侵染所造成,而出胶量高则是生理活性强的表现。沙枣胶的生产应该在新疆炎热的南疆地区进行,加强林带的管理和复壮有利于提高沙枣树的产胶量。 相似文献
865.
Zsuzsanna Nyári Ali Ismet Kanlı János Stickel Axel Tillmann 《Journal of Applied Geophysics》2010,70(3):255-265
The spatial distribution of the electrical resistivity data provides useful information for investigating and modeling the fluid transport processes. 3D electrical resistivity distribution provides information about water flow and changes in electrical resistivity of the pore fluid.Therefore, to assist in understanding and modeling of the fluid transport process, 3D spatial distribution of the electrical resistivity data with the corresponded 3D geological section were mapped and interpreted in the test site located in western Germany. A process of deriving electrical resistivity values from the mechanical and radioactive parameters of cone penetration tests (CPT) and geological information of boreholes was presented. A reliable method which gives accurate resistivity values in cases of near surface sediments was introduced. Then a field test was executed where the calculated resistivity values were compared with the measured CPTe resistivity data. The CPTe (cone penetration test with electrical extension) data were also used in correlating to the ERT (electrical resistivity tomography) data. Consequently, obtained dense CPT surveys give us the possibility to determine a high resolution resistivity distribution of the investigated area. 相似文献
866.
867.
Evaluating the persistence of post‐fire residual patches in the eastern Canadian boreal mixedwood forest
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Samira Ouarmim Adam A. Ali Hugo Asselin Christelle Hély Yves Bergeron 《Boreas: An International Journal of Quaternary Research》2015,44(1):230-239
In boreal forest ecosystems, wildfire severity (i.e. the extent of fire‐related tree mortality) is affected by environmental conditions and fire intensity. A burned area usually includes tree patches that partially or entirely escaped fire, called ‘residual patches’. Although the occurrence of residual patches has been extensively documented, their persistence through time, and thus their capacity to escape several consecutive fires, has not yet been investigated. Macroscopic charcoal particles embedded in organic soils were used to reconstruct the fire history of 13 residual patches of the eastern Canadian boreal mixedwood forest. Our results display the existence of two types of residual patches: (i) patches that only escaped fire by chance, maybe because of local site or meteorological conditions unsuitable for fire spread (random patches), and (ii) patches with lower fire susceptibility, also called ‘fire refuges’ that escaped at least two consecutive fires, probably because of particular site characteristics. Fire refuges can escape fire for more than 500 years, up to several thousand years, and probably burn only during exceptionally severe fire events. Special conservation efforts could target fire refuges owing to their old age, long ecological continuity and potential specific biological diversity associated to different microhabitats. 相似文献
868.
Capabilities of satellite precipitation datasets to estimate heavy precipitation rates at different temporal accumulations
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The importance of satellite datasets as alternative sources of precipitation information has been argued in numerous studies. Future developments in satellite precipitation algorithms as well as utilization of satellite data in operational applications rely on a more in‐depth understanding of satellite errors and biases across different spatial and temporal scales. This paper investigates the capability of satellite precipitation data sets with respect to detecting heavy precipitation rates over different temporal accumulations. In this study, the performance of Tropical Rainfall Measuring Mission real time (TRMM‐RT), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks and CPC MORPHing (CMORPH) is compared against radar‐based gauge‐adjusted Stage IV data. The results show that none of the high temporal resolution (3‐h) datasets are ideal for detecting heavy precipitation rates. In fact, the detection skill of all products drops as the precipitation thresholds (i.e. 75 and 90 percentiles) increase. At higher temporal accumulations (6, 12 and 24 h), the detection skill improves for all precipitation products, with CMORPH showing a better detection skill compared to all other products. On the other hand, all precipitation products exhibit high false alarm ratios above the heavy precipitation thresholds, although TRMM‐RT lead to a relatively smaller level of false alarms. These results indicate that further efforts are necessary to improve the precipitation algorithms so that they can capture heavy precipitation rates more reliably. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
869.
870.