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漳河水库由观音寺水库和鸡公尖水库通过半天然明槽相互连通组成，因受库水位观测、明槽输水计算、动库容计算误差等的复杂影响，以往多次建立的洪水预报方案均未达到可供应用的水平。在分析漳河水库入库洪水误差产生特点的基础上，通过建立抗误差产汇流预报模型和自适应实时校正技术，使漳河水库洪水预报方案平均确定性系数达91.09%，洪峰合格率达100%，峰现时间合格率达90.91%；观音寺水库洪水预报方案的平均确定性系数达90.63%，洪峰合格率达100%，峰现时间合格率达100%，终于建立了达到甲等水平的漳河水库洪水预报应用方案。 相似文献
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Gill Reaction to Pollutants from the Tamiš River in Three Freshwater Fish Species,Esox lucius L. 1758, Sander lucioperca (L. 1758) and Silurus glanis L. 1758: A Comparative Study 
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下载免费PDF全文 J. Lujić M. Matavulj V. Poleksić B. Rašković Z. Marinović D. Kostić B. Miljanović 《Anatomia, histologia, embryologia》2015,44(2):128-137
The study evaluated the effects of waterborne pollutants from the Tami? River on gill histology and possible differences in gill reaction patterns between three freshwater fish species, pike Esox lucius L. 1758, pike‐perch Sander lucioperca (L. 1758) and wels catfish Silurus glanis L. 1758 from the Tami? River. Gills from analysed fish species showed moderate to intense histopathological alterations. The most frequent progressive alteration was hyperplasia of epithelium, whereas the most frequent regressive alteration was epithelial lifting. Circulatory disturbances were most often manifested in the form of hyperaemia. During comparative analysis, differences in gill indices, reaction and alteration indices, as well as in gill and filament prevalence between analysed species, were observed. Although all analysed fish species did show both progressive and regressive alterations, there was a significant difference in the level of expression of these reaction patterns. Gill index obtained for pike clearly stands out as the lowest. Wels catfish showed the highest progressive reaction index, significantly higher in comparison with the other two species (P < 0.05), while pike‐perch showed the highest regressive reaction index, also significantly higher in comparison with the other species (P < 0.001). These results may implicate species‐specific gill reactions and thus present a useful tool for better understanding toxic mechanisms of various pollutants. 相似文献
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The effect of footrot on body weight and wool growth of sheep 总被引：1，自引：0，他引：1
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured. 相似文献
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Oil emulsion inactivated vaccine was prepared by susceptible embryos, with different strains of AEV. Four groups of normal chickens of 2 - 7 days of age were given injections for immunization, respectively. Another group was used as control. This study was expected to evaluate the immunological effect and discuss the immunological mechanism by means of five different experiments, i.e. the agar-gel precipitin test,the isolation of lymphokine, the isolation, purification and analysis of blood serum IgG, embryo-susceptibility test, and clinical and pathological examination. The results of these experiments indicated that oil emulsion inactivated vaccine is safe and effective. The chickens were normal when inoculated with AE strong virus after immunity at 4 and 37 weeks. Immunological mechanism is that the humoral immunity played an important role and celluar immunity exists, but it is not important in the process of the resistance to AEV. 相似文献
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Milica Marković Tea Zuliani Snežana Belanović Simić Zorana Mataruga Olga Kostić Snežana Jarić Janja Vidmar Radmila Milačič Janez Ščančar Miroslava Mitrović Pavle Pavlović 《Journal of Soils and Sediments》2018,18(12):3404-3414
Purpose
Riparian zone contamination is a growing problem for several European catchments due to high anthropogenic pressures. This study investigates As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in the Sava River riparian zone, characterized by wide agricultural areas, various geological substrates, and different types of industrial pollution. The accumulation and mobility of these elements were studied because they are listed as priority substances in the Water Framework Directive and environmental objectives for surface waters.Materials and methods
Sampling was performed during the sampling campaign of the EU 7th FW-funded GLOBAQUA project in September 2015 during a low-water event. Soil samples were collected along the Sava River at 12 selected sampling sites, from a depth of 0–30 cm, at a distance of 10–15 m from the river bank. The extent of pollution was estimated by determining total and readily soluble element concentrations in the soils. Potential ecological risk and the source of the selected elements in the soils was determined using the enrichment factor (EF), potential ecological risk index (RI), and statistical methods such as the principal component analysis (PCA) and multiple linear regression analysis (MLRA).Results and discussion
This study showed that concentrations of the selected elements increase along the Sava. In terms of origin, PCA and MLRA indicated that Cr and Ni in soils are predominantly lithogenic, while As, Cd, Pb, and Zn are both lithogenic and anthropogenic (ore deposits, industry, and agriculture). PCA singled out Cu since its origin in soil is most probably from specific point-source pollution. EF was generally minor to moderate for most of the examined elements, apart from Cu, for which the EF was significant at one sampling site. Overall ecological risk (RI) fell within the low-risk category for most sites, apart from Belgrade sampling site (BEO), where high total Cd content affected individual and overall ecological risk indicators, indicating Cd could represent a considerable ecological risk for the downstream riparian zone.Conclusions
At downstream sites, there was a noticeable increase in PTE content, with Cd, Cr, Ni, and Zn exceeding the proposed threshold values for European soils, indicating rising contamination in riparian soils. In terms of the ecological risk, only Cd could pose a potential ecological threat for the downstream riparian zone.9.
在香梨 4年生幼林园内 ,进行了常规沟植、渠道内外两行树木的新梢生长量、叶片生长状况和蒸腾速率、气孔阻抗、叶温、叶温与气温差日变化的测定。结果表明 ,渠外行的各项生理指标均好于沟植和渠内行。揭示了影响树木生长的水分生理状况和过程。提出了生产中要提倡渠外行栽种香梨 ,保持沟植香梨 ,放弃渠内行栽植香梨的生产模式理论依据。 相似文献
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Ana D. Kramar Koviljka A. Asanović Bratislav M. Obradović Milorad M. Kuraica Mirjana M. Kostić 《Fibers and Polymers》2018,19(3):571-579
Cellulose fabrics (viscose and cotton) were treated with atmospheric pressure dielectric barrier discharge (DBD) in air. After DBD treatment, samples were characterized and volume electrical resistance was measured under different relative humidity conditions (φ=40-55 %). Results have shown that DBD treatment increases wettability and polar surface functional groups content, which consequently causes a decrease of volume electrical resistivity of cellulose fabrics in measured relative humidity range (φ=40-55 %). Metal ions (silver, copper, and zinc) were incorporated in untreated and plasma treated samples through sorption from aqueous solutions and incorporation of metal ions into plasma treated cellulose samples decreased electrical resistivity even further. Resistivity of cotton and viscose fabrics with incorporated metal ions followed the order Zn2+ > Cu2+ > Ag+. The most pronounced decrease, for entire order of a magnitude, was obtained by modification of cotton fabric with DBD and silver ions, where value of resistivity dropped from GΩ to a several dozens of MΩ. 相似文献