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21.
Defining impact significance is the main technical task that influences decision-making during the Environmental Licensing Procedure(ELP).The ELP begins with screening to determine potentially signif-icant impacts of the proposed project.Scoping then follows to address any interventions deemed worthy of attention in the production of an Environmental Impact Assessment(EIA).This will include consider-ation of relevant landforms and geomorphological processes.However,preliminary assessments of envi-ronmental impacts often lack the scientific robustness to procure substantive and transactive effectiveness.This review presents an examination of the established practices of screening and scoping while highlighting the foremost challenges to improve the technical grounds of the ELP.The analysis of screening and scoping practices stresses the need for novel methods that ensure the sequential reasoning between their criteria while improving the preliminary evaluation of impact significance.Reducing the inherent subjectivity of discretionary judgment requires scientific methodologies that acknowledge the interaction between the natural system and human interventions,which has been addressed by geomor-phological research.The knowledge consolidated in this review opens the gate to explore the compatibil-ity between the United Nations strategy of Ecosystem Approach(EA)with the ELP through a novel geomorphological interpretation of the EIA.Therefore,this diagnosis demonstrate that screening and scoping practices would benefit from reliable methods that balance the precautionary principle with the efficient character required in the ELP.  相似文献   
22.
采用点种法并以副溶血弧菌(Vp1.2164)和溶藻弧菌(Va-Y)为弧菌指示菌,对从健康的大黄鱼肠道内分离的115株细菌进行体外拮抗试验。并对筛选出的拮抗菌进行抗菌谱测定,最后利用VITEK-32细菌快速鉴定系统和16SrRNA基因序列对拮抗菌进行鉴定。结果表明,从中筛选到3株有较强拮抗作用的菌株,编号分别为X1402-1、X1108和X3914,且菌株X1402-1的抗菌作用最强,抗菌谱最广,21株病原指示菌中,对16株均能产生较强的抑制作用,其中对Vp-1.2164的抑菌直径最大,达到28.5mm,对Va-Y的抑菌直径为8.7mm;其次为菌株X1108和X3914,对两种指示弧菌的抑菌直径分别为:12.0mm、9.0mm和0mm、7.2mm。经VITEK-32细菌快速鉴定系统鉴定,3株拮抗菌分别与铜绿假单胞菌,恶臭假单胞菌,地衣芽孢杆菌的相似性均为99%。通过16SrRNA基因序列分析表明,3株拮抗菌分别与类产碱假单胞菌Pseudomonas pseudoalcaligenes(EU419918)、恶臭假单胞菌Pseudomon asputida(FJ440105)和地衣芽孢杆菌Bacillus licheniformis(DQ988136)的16SrRNA基因同源性最高,分别为100.0%、97.5%、99.0%。综合分析试验结果,X1402-1、X1108和X3914分别被确定为类产碱假单胞菌、恶臭假单胞菌和地衣芽孢杆菌。  相似文献   
23.
根据围岩蚀变在多波段遥感图像(TM)上具有的光谱特征,利用比值分析、主成分分析及比值增强后主成分分析等方法,对 四川省稻城地区围岩蚀变信息进行提取和分析,通过多层次的筛选和评估提取矿区异常区,制作遥感异常图。  相似文献   
24.
Ten algae species were analyzed by comparing their growth in specific hypersaline industrial wastewater. It was a by‐product of fertilizer production which was released by K + S Aktiengesellschaft, Germany. Due to processing, brine water contains a high amount of salts ( 200 g L?1). A successful algal biotechnology mainly depends on choosing and screening the adequate algae for a specific application along with the design of optimal culture conditions with comparable photo bioreactor technologies. Therefore, a high throughput screening technology was developed. In comparison to glass flasks or flat panel reactors this system was eligible for screening applications because of disposable characteristics and the equability of each culture tube. Dunaliella salina, Tetraselmis tetrathele, and Nannochloropsis salina grew in the presence of hypersaline wastewater where T. tetrathele grew best to a wastewater concentration of 75% by salt shock experiments. D. salina tolerates a wastewater level up to 80% by gradual increase. Intracellular ion contents of lyophilized algae samples were measured. They feature special transporter to either exclude ions, i.e., sodium from the cell, or to include ions like potassium and magnesium in order to secure functionality of sensitive enzymes. Under saline stress conditions these transport systems as well as metabolic pathways leading to the production of compatible osmolytes could be induced. Stress tolerance mechanisms developed in initially unstressed culture either by stepwise adaptation or by shock exposure to harsh salt condition. For this reason a feasible mass production in industrial hypersaline wastewater was possible.  相似文献   
25.
采用筛分脱泥、一级旋流脱泥、二级旋流脱泥、旋流-筛分脱泥4种脱泥工艺对马海盐湖高不溶物、低品位地表固体钾矿进行了脱泥试验,给出了试验结果。试验结果表明,马海盐湖高不溶物、低品位地表固体钾矿经旋流-筛分脱泥后,脱泥矿可以达到浮选法生产氯化钾对原料不溶物的要求,使高不溶物地表固体钾矿得到了较好的开发利用,高效利用了钾资源。  相似文献   
26.
4株对虾肠道益生菌的筛选及鉴定   总被引:3,自引:1,他引:2  
采用体外拮抗试验的方法,先从不同生长阶段的对虾肠道中分离的96株细菌中筛选出4株对病原菌(鳗弧菌、副溶血弧菌、哈维氏弧菌)有拮抗作用的细菌;进一步通过固体扩散法和液体混合法确定LV060806、LV060808的产物对鳗弧菌有明显抑制作用,Lv060806、LV060815的产物对副溶血弧菌有明显抑制作用,LV060810、LV060815的产物对哈维氏弧菌有明显抑制作用。溶血试验证实这些菌株不产生溶血素,不具有潜在的致病性;动物安全性实验证实菌株浓度在10^6 cfu/ml以下对实验对虾无明显的毒害作用。随后测定了其16S rRNA基因序列,分析了相关细菌相应序列的同源性,构建了系统发生树,结合菌株表型特征和生理生化特性最终鉴定结果为:LV060806、LV060808为Vibrio natriegens;LV060810、LV060815为V.alginolyticus。  相似文献   
27.
Response of soil media due to impulse loads and isolation using trenches   总被引:1,自引:0,他引:1  
This paper examines the effectiveness of open and filled trenches for screening Rayleigh waves due to impulse loads for 3D problems. The effects of the geometric parameters of trench reducing ground displacements are studied in detail. The computational scheme involves the use of finite element method to discretize a large computational domain and the resulting integration dynamic equilibrium equations are integrated to get the response using Newmark's β method. Soil has been idealized as linear, isotropic continuum.  相似文献   
28.
It is shown that the presence of 31-35 commonly measured volatile organic compounds(VOCs)inground water can be detected with small error rates by using screening methods which analyze for a subsetof such VOCs.A study of selected data sets indicates that analytical determinations of only from twoto eight VOCs will suffice to detect 95% of all VOC hits.It is also shown that a serially optimal algorithmfor selecting the VOCs for screening is very nearly as accurate as a globally optimal algorithm and mucheasier to implement.These conclusions are supported by empirical evidence from two drinking-water datasets and one hazardous waste site data set.Additional research areas are also outlined.  相似文献   
29.
Application of an Enzyme Immunoassay for the Detection of Mecoprop in a Ground water Screening Procedure A competitive solid-phase enzyme immunoassay based on rabbit polyclonal antibodies was tested for its reliability. This assay, used for the detection of the phenoxycarboxylic acid mecoprop [2-(4-chloro-2-methylphenoxy-)propionic acid], has already been characterized in terms of middle of the test (0.36 μg/L at 50% B/B0) and detection limit (0.06 μg/L at 80% B/B0) by Weber (Acta hydrochim. hydrobiol. 22, 53–59 (1994)). For the reliability test, a small number from a batch of one hundred groundwater samples were spiked. The analyst was neither aware of which nor of how many samples were spiked. The spiked samples were all detected as positive. There were no false negative results. From these findings, values of 1 were obtained for the diagnostic sensitivity and for the diagnostic specificity. Based on these results, the mecoprop contents of 228 groundwater samples from various waterlevel gauges of a test field were determined. The test site had previously been treated repeatedly with this herbicide. Confirmation of the enzyme immunoassay results was carried out by GC/MS. This showed that the enzyme immunoassay gave one false positive result only. All other results from immunoassay and GC/MS showed good correlation.  相似文献   
30.
张文宣  赵南 《铀矿地质》1998,14(1):54-57
针对赤霉素工业生产菌株皆为多核多细胞菌丝型,不产生孢子的特性,首先将赤霉素菌丝体通过酶解手段,溶去其细胞壁使其成为单一细胞游离的原生质体,并在此基础上通过紫外线等理化诱变,使其产生基因突变,然后在再生平板上,使赤霉素原生质体中的突变型菌株得到再生,最后通过摇瓶筛选,得到一株生产水平高、生产性能稳定的高产赤霉素菌株。  相似文献   
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