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91.
生物强化修复石油污染土壤 总被引:2,自引:0,他引:2
筛选高效石油降解菌,考察菌株的降解性能及降解机理,进行花盆模拟高效外源菌强化修复石油污染土壤实验,在降解后期添加激活剂H2O2以及木屑来试图改善微生物的修复环境,减缓微生物的衰亡,并考察修复效果。结果表明,菌株L-1的降解效果较好,其对pH和温度有较大范围的适应性,能分泌较多的表面活性物质,细胞疏水性较强。将其应用于土壤修复中,经过50 d的修复,石油残留率达到50.6%左右,生物强化比自然修复残留率降低了8%左右。在第45天添加激活剂能有效改善修复效果,70 d时添加外源菌的土样最小石油残留率达到37.9%。 相似文献
92.
利用海南省18个气象台站的雷暴人工观测资料和海南闪电定位网的观测资料,分析了海南文昌火箭发射场的雷暴特征和雷电环境,结果表明:海南岛的中部和北部雷暴活动较强,西部、东部和南部近海地区的雷暴活动较弱,文昌发射场处在北部较强的雷暴区;采用Krigine(克里格)方法拟合的结果为文昌火箭发射场雷暴日数的年变化从1982年以后逐渐减少,发射场一年中各月都有雷暴发生,4-10月为雷暴高发期;发射场西部、西北部和北部区域雷暴活动较其它区域要强,79%的雷电流强度小于40 kA,而只有5.9%的雷电流强度大于60 kA,一天中闪电的发生有两个高峰时段,一个出现在凌晨5时到6时,另一个时段出现在14时到18时,午后15时左右是闪电活动最频繁的时段。 相似文献
93.
Zhuoyu Li Guangzhao Xie Hui Chen Bixin Zhan Lin Wang Yujing Mu Abdelwahid Mellouki Jianmin Chen 《环境科学学报(英文版)》2022,34(4):221-232
As a secondary pollutant of photochemical pollution, peroxyacetyl nitrate(PAN) has attracted a close attention. A four-month campaign was conducted at a rural site in North China Plain(NCP) including the measurement of PAN, O3, NOx, PM2.5, oxygenated volatile organic compounds(OVOCs), photolysis rate constants of NO2 and O3 and meteorological parameters to investigate the wintertime characterization of photochemistry from November 2018 to Fe... 相似文献
94.
GIS环境下大区域工程场地地震液化势的二维概率评价方法 总被引:1,自引:0,他引:1
用具有概率意义的饱和砂土抗液化强度经验公式来对大区域场地进行地震液化势二维概率评价;在GIS软件ArcGIS的支持下,将取样钻孔处的液化势评价结果等价于数字高程模型(Digital Elevation Model,DEM)中的高程,利用ArcGIS空间分析模块中的Kriging插值法估计大区域场地的地震液化范围。研究表明:将Kriging法应用于岩土工程地质特征的统计推断,有助于揭示勘探孔以外的地层信息,对于大区域场地地震液化范围的判别是一个较好的手段;利用ArcGIS空间分析模块中的Kriging法,通过已勘察点的信息(液化势)来估计未勘测点的土层液化势,能够较好地区划出场地地震液化势的空间分布特征。 相似文献
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97.
Abstract The sorption and desorption characteristics of four herbicides (diuron, fluometuron, prometryn and pyrithiobac‐sodium) in three different cotton growing soils of Australia was investigated. Kinetics and equilibrium sorption and desorption isotherms were determined using the batch equilibrium technique. Sorption was rapid (> 80% in 2 h) and sorption equilibrium was achieved within a short period of time (ca 4 h) for all herbicides. Sorption isotherms of the four herbicides were described by Freundlich equation with an r2 value > 0.98. The herbicide sorption as measured by the distribution coefficient (Kd) values ranged from 3.24 to 5.71 L/kg for diuron, 0.44 to 1.13 L/kg for fluometuron, 1.78 to 6.04 L/kg for prometryn and 0.22 to 0.59 L/kg for pyrithiobac‐sodium. Sorption of herbicides was higher in the Moree soil than in Narrabri and Wee Waa soils. When the Kd values were normalised to organic carbon content of the soils (KoC), it suggested that the affinity of the herbicides to the organic carbon increased in the order: pyrithiobac‐sodium < fluometuron < prometryn < diuron. The desorption isotherms were also adequately described by the Freundlich equation. For desorption, all herbicides exhibited hysteresis and the hysteresis was stronger for highly sorbed herbicides (diuron and prometryn) than the weakly sorbed herbicides (fluometuron and pyrithiobac‐sodium). Hysteresis was also quantified as the percentage of sorbed herbicides which is not released during the desorption step ω = [nad / nde ‐1] x 100). Soil type and initial concentration had significant effect on ω. The effect of sorption and desorption properties of these four herbicides on the off‐site transport to contaminate surface and groundwater are also discussed in this paper. 相似文献
98.
The objective of the project was to identify all hazardous waste sites in Burlington County, New Jersey that could be detected on existing, medium-scale aerial photographs of the county. The complete set of over 1000 black- and-white stereopairs at a scale of 1:12,000 was carefully examined for initial identification of possible sites. All suspicious sites were examined again on color transparencies of the county at the same 1:12,000 scale. Out of the 1094 black- and-white photos, 250 required further checking on color transparencies using a zoom stereoscope. This examination resulted in a final identification of 67 sites, the locations of which were delineated on 1:24,000 USGS maps. The use of air photo interpretation techniques provided an effective procedure for identifying waste sites quickly as well as providing a useful demonstration program for county and state officials. 相似文献
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100.
Stephen C. Newbold 《Journal of the American Water Resources Association》2002,38(2):341-353
ABSTRACT: This paper presents an optimization framework for prioritizing sites for wetlands restoration on a watershed or landscape scale. The framework is designed for analyzing the potential environmental impacts of alternative management strategies while accounting for economic constraints, thereby aiding decision makers in explicitly considering multiple management objectives. The modeling strategy consists of two phases. First, relationships between the configuration of land use types in a watershed and valued ecosystem services are specified mathematically. Second, those functions are incorporated into a spatial optimization model that allows comparisons of the expected environmental impacts and economic costs of management strategies that change the configuration of land use in the watershed. By way of a stylized example, this paper develops the general structure of the framework, presents simulation results based on two production functions for ecosystem services, and discusses the potential utility of the methodology for watershed management. 相似文献