共查询到19条相似文献,搜索用时 78 毫秒
1.
2.
3.
舟山市海洋贝类生物体内的细菌学研究 总被引:1,自引:0,他引:1
对浙江省舟山市各区县海洋贝类体内细菌数量及优势细菌种类进行了初步研究。根据2004年8月的采样和实验室分析,结果表明,贝类生物体内的优势种为少动鞘氨醇单胞菌、温和气单胞菌、欧文氏菌属等,一些能够诱发疾病的如杀鲑气单胞菌、溶藻弧菌、腐败假单胞菌等的出现应当引起重视。对生物体内的细菌数量检测发现,弧菌和粪大肠菌群数量都比较高,弧菌的测值范围为50个/克~1.8×104个/克,几何平均为9.3×102个/克;粪大肠菌群的测值范围为2.0~23个/克,几何平均为12.0个/克,超国家海洋生物体内粪大肠菌群二类标准,超标率为91.7%。 相似文献
4.
大气细菌是大气污染物的重要方面.在适宜条件下,可使人畜致病,农作物减产,危害甚大.目前,我国对大气细菌污染程度的研究多以空气中存在细菌数量多少表示,不能反映大气细菌污染的实际危害.本文依据某些溶血菌产溶血毒素可使血液琼脂培养基产溶血圈的特点,对齐市地区大气细菌污染程度进行了研究. 相似文献
5.
通过对2021年1月1日—12月31日人民网舆情系统搜集到的江苏范围内涉及生态环境各个要素的舆情进行综合分析,重点对敏感舆情进行不同地区、环境要素、发布时间的量化分析。结果表明,2021年全年环境问题舆情数量呈现波动式分布,水污染和空气污染是各设区市普遍存在的问题;在地域分布上,盐城、苏州和南京敏感舆情数量最高,徐州、连云港、淮安敏感舆情数量最少。通过对3个典型高热舆情案例进行剖析,了解敏感舆情产生的原因,指出由于部分地方管理部门对于环境舆情不够重视、回应不及时,外埠媒体介入以及环境保护领域有影响力的专家发声等原因导致了一些环境问题演化成为敏感舆情。提出,应未雨绸缪做好舆论引导,结合各地环境特点采取针对性措施,畅通沟通渠道加强舆情应对主动性,以期处理好江苏省内生态环境公众关系。 相似文献
6.
采用Hakonson生态风险指数法对京杭运河苏州段近十年来底泥重金属污染进行评价,对其空间分布和时间分布规律进行了分析。结果表明,京杭运河苏州段重金属为低生态风险等级,汞和镉为主要的生态风险因子,城区老运河段重金属生态风险指数最高。近十年来,京杭运河苏州段底泥重金属潜在生态风险指数呈下降趋势,重金属污染得到有效的控制。 相似文献
7.
8.
9.
研究了不同填料的厌氧填充柱中微生物去除四氯化碳的特点、效率以及规律。厌氧填充柱完成填料挂膜后,定期测定不同高度处四氯化碳质量浓度及细菌的数量,结果表明,在25℃条件下,不同的填充柱中,发酵性细菌在数量上均比硫酸盐还原菌占较大优势;混合厌氧菌对四氯化碳有较好的降解作用,对四氯化碳的降解率最高可以达99.1%;以活性炭作为填料的填充柱对四氯化碳的降解效率高于其他填料的填充柱。 相似文献
10.
苏州河干流水质自动监测系统数据的可靠性分析 总被引:4,自引:3,他引:1
以苏州河干流水质自动监测系统为例,通过与实验室数据之间的统计分析,分析苏州河水质在线自动监测系统数据的可靠性。对比分析自动监测系统和实验室的温度、p H、DO、CODMn、NH3-N数据,自动监测系统数据合格,在0.01水平上两者不存在显著性差异,2种方法的结果高度相关,苏州河水质在线自动监测系统测定的数据真实可靠。在自动监测系统的维护中,要对系统关键部分进行不定期的清洗,特别是出现较可疑数据时,应及时寻找原因,解决问题。 相似文献
11.
12.
Yue Che Kai Yang Enuo Wu Zhaoyi Shang Weining Xiang 《Environmental monitoring and assessment》2012,184(12):7425-7438
Restoration of urban streams and rivers has increased rapidly in developing countries in recent years. Estimating river health provides a new perspective on evaluating the ecological conditions of streams and rivers. The Suzhou Creek restoration project in Shanghai, China is a milestone for environmental protection. Based on the environmental and ecological data, including 17 indicators in five categories, collected from March 11 to April 20, 2007, the river health index (RHI) for Suzhou Creek was constructed and analysed to quantify the ecosystem of this urban river after a restoration project. The RHI scores of 34 sites ranged from 19.24 to 33.36, i.e. from poor to good. There were no significant RHI differences among stream orders, while differences in land use resulted in significant differences in channel flow status (B12), channel alteration (B21), channel sinuosity (B22), bank stability (B23), bank profile type (B25) and riparian vegetative zone width (B31). River restoration led to improved hydrological condition and channel physical form, while ammonia nitrogen (B44) and indicator scores of the presence of macro-invertebrate families (B51) were the lowest of any indicator. This case study supports the use of river health assessment as a supplement to water quality analysis in China. 相似文献
13.
用沉积物富集系数法和Hakanson潜在生态风险评估法对上海市黄浦江表层沉积物重金属含量进行了评价。结果显示,沉积物中Cd、As和Pb含量富集程度较低,Hg和Cu含量富集程度较高;其分布特征为上游段含量相对较轻,到中游段有所上升,至下游段含量又有所下降,整体呈钟型分布,重金属含量分布规律可能与苏州河对黄浦江下游沉积物的影响和黄浦江中游段有工业污染排放输入有关;河口与内陆河流沉积物中重金属含量存在差异性,河口重金属含量明显下降;调查区37.5%的断面Hg含量潜在生态危害为中等;沉积物富集系数法可用来评价重金属累积程度,而潜在生态风险指数则突出对生物有很强毒性的重金属作用。 相似文献
14.
A screening-level assessment of dissolved zinc from inactive and abandoned metal mines in the Cement Creek Basin was performed. The basin is part of the Upper Animas River Basin in the San Juan Mountains of southwestern Colorado. Stream discharge and dissolved zinc concentrations were measured at 49 stations below nonpoint sources including tailings and waste rock, point sources such as adits, and background areas. One measurement was made at a station during three flow events: storm runoff, peak snowmelt runoff, and baseflow. The highest concentrations occurred in the upper part of the basin immediately downstream from nonpoint and point source discharges, especially in the North Fork of Cement Creek. The mean concentration in Cement Creek was highest during baseflow (1350 g l-1) and lowest during snowmelt (796 g l-1). Most exceedances of national acute and chronic criteria for brown trout were chronic criteria exceedances in the upper part of the basin. Subareas with the greatest extent of nonpoint source areas in the upper part of the watershed, especially those contributing to Upper Cement Creek and the North Fork of Cement Creek, generally had the highest loadings and unit area loadings. The greatest loadings from all subareas to Cement Creek occurred during snowmelt (219 000 g day-1 and 17 400 kg for the snowmelt season). The highest unit area loadings from all subareas also occurred during snowmelt (190 g ha-1 day-1 and 15 147 g ha-1 for the snowmelt season). Loadings from subareas with extensive nonpoint source areas were always much greater than those from point sources and background areas. 相似文献
15.
Angela M. Leung D. Matthew McDonough C. David West 《Environmental monitoring and assessment》1998,50(1):85-94
The extent of contamination by endosulfans in soil samples collected from the Point Mugu watershed near Oxnard, California was determined using capillary gas chromatography/mass selective detection (GC/MSD). The study was designed to detect three organochlorinated pesticides: endosulfan , endosulfan and endosulfan sulfate. Thirteen sets of two soil samples each were taken from various sites in the region. Our results show that the endosulfan levels in these soils range from trace amounts to nearly 30 ppm, with endosulfan being the most abundant and endosulfan sulfate the least. Two sites of the study, Hueneme and Revolon and Farm and Revolon, showed high amounts of endosulfans and , with concentrations between 20 and 30 ppm. The majority of the other sites studied in this research produced concentrations of less than 10 ppm for each of the three endosulfans monitored. At five areas in particular, Pleasant Valley and Creek, Laguna and Creek, Etting and Creek, Road and Creek and Hueneme and Creek, less than 2 ppm or only trace amounts of endosulfans , and sulfate were detected. 相似文献
16.
17.
Nine stream sites in the Blackfoot River, Salt River, and Bear River watersheds in southeast Idaho, USA were sampled in May 2001 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness, and specific conductance were relatively uniform among the nine sites. Of the aquatic components assessed, water was the least contaminated with selenium because measured concentrations were below the national water quality criterion of 5 g/L at eight of the nine sites. In contrast, selenium was elevated in sediment, aquatic plants, aquatic invertebrates, and fish from several sites, suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium was elevated to concentrations of concern in fish at eight sites (> 4 g/g in whole body). A hazard assessment of selenium in the aquatic environment suggested a moderate hazard at upper Angus Creek (UAC) and Smoky Creek (SC), and high hazard at Little Blackfoot River (LiB), Blackfoot River gaging station (BGS), State Land Creek (SLC), upper (UGC) and lower Georgetown Creek (LGC), Deer Creek (DC), and Crow Creek (CC). The results of this study indicate that selenium concentrations from the phosphate mining area of southeast Idaho were sufficiently elevated in several ecosystem components to cause adverse effects to aquatic resources in southeastern Idaho. 相似文献
18.
19.
简述了1990年—2000年苏州市区水系的变化及京杭运河苏州段沿岸主要工业污染源的变化,对苏州市区水环境质量的变化进行了分析。指出,苏州市区水环境质量的变化主要受水系的改变和污染源防治的共同影响。提出,除继续加强对工业污染源的防治外,还需对水系范围内的生活、农业等方面产生的污染进行防治;在规划水利建设工程时,应将水环境质量的改善与生态建设全面地比较与评价,按其结果再实施工程建设;已建成的环太湖闸在不影响其主要功能的情况下,应保持开启,让优质的太湖水补给运河,从根本上改善苏州市区水环境质量。 相似文献