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71.
The effect of altitude and water temperature on biomonitoring of freshwater quality was examined along an unpolluted area (36 km in length) of the upper Río Tajo (central Spain). The macrobenthic and fish communities were studied, and the Biological Monitoring Water Quality (BMWQ) method was applied. As expected, values of altitude and temperature respectively decreased and increased with increasing distance from the river source; these two physical parameters exhibited a negative and significant (P<0.05) correlation coefficient between them. However, despite evident changes in the functional structure of both aquatic communities along the study area, BMWQ scores were similar at all sampling sites. Pearson correlation coefficients between physical and biological parameters were not significant (P>0.05). The BMWQ index only exhibited significant (positive) correlation coefficients with macrobenthic and fish biomasses, indicating that freshwater quality could affect the biological production of fluvial ecosystems. It is concluded that biomonitoring of freshwater quality may be independent of the influence of altitude and water temperature at local spatial scales. Nonetheless, further investigations would be needed to clearly differentiate between the effects of anthropogenic and natural causes on biological monitoring at larger spatial scales. 相似文献
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73.
The province of Huelva in the SW of Spain presents high environmental contrasts: together with the great abundance of natural spaces, it shows the impacts of historical natural resources exploitation processes. In the Ria of Huelva, the effluents of the chemical industries must be added to the contaminating inputs of the Tinto and Odiel rivers, coming from the acid drainage of the mines located in the Iberian Pyrite Belt. This forced the Environmental Agency (AMA) to elaborate in 1987 an Effluent Remediation Plan in order to negate unacceptable environmental impacts. The application of a grey box systemic analysis to the AMD pollution, undergone by the Tinto and Odiel rivers has allowed to set a conclusive explanation of the sampling results observed for a period of 11 years, thus making available an overall view of the polluting process and, above all, an explanation of its partial aspects. 相似文献
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75.
研究了表面活性剂(乳化剂OP)存在下,铁、邻菲罗啉、曙红的显色反应.该离子缔合物的最大吸收波长为545 nm,摩尔吸光系数为9.4×104 L·mol-1·cm-1,铁含量在0-0.4 mg/L内符合比耳定律.以自来水为基体进行铁的回收实验,回收率在99%以上. 相似文献
76.
An approach was developed to identify surface soils affected by historical dredged sediment disposal in the alluvial plains of the Upper Scheldt, the Sea Scheldt and the Leie river. Dredged sediment-derived soils were identified based on field observations, comparative granulometric analyses and chemical analyses. Criteria developed were based on a comparison between reference data from 102 aerobic soil samples of areas known to be affected by dredged sediment disposal and 104 samples from undisturbed alluvial soils along the studied rivers. A comparative grain size analysis with optical laser diffractometry between the A and C horizon proved useful for the identification of levelled-up sites. The chemical soil characteristics that were most useful in identifying dredged sediment-derived soils were CaCO3, sulfur (S), organic carbon (OC) and phosphorus (P) contents, electrical conductivity (EC), and the C/P and C/S ratios. Criteria for concluding the origin of an investigated soil were specific for the studied area, but the approach presented may provide useful guidelines for developing criteria valid for different regions. 相似文献
77.
乌鲁木齐市采暖季空气质量变化趋势分析 总被引:7,自引:0,他引:7
为了定量评价乌鲁木齐市采暖季空气污染近五年的治理成效,给环境治理决策提供科学依据,运用回归分析方法,对乌鲁木齐市采暖季空气质量的浓度、级别和变化规律进行回归分析。分析结果表明,PM10、SO2、NO2三项污染物的浓度都有所下降,空气质量级别的污染天数呈现明显的月变化规律。乌鲁木齐市采暖季空气的重污染状况有所遏制,但SO2污染凸现,在下一步的治理工作中,加强尘污染治理的同时要加大对SO2的治理力度。 相似文献
78.
构建了经济发展与生态环境评价指标体系,选用耦合协调度模型计算2010—2019年安徽省不同区域经济发展与生态环境的耦合协调度,并采用灰色关联度法计算评价指标与耦合协调度的关联系数。研究结果表明:全省经济发展与生态环境的耦合协调度整体呈改善趋势,耦合协调度集中分布在0.393~0.765,基本处于良好协调或低水平协调阶段。全省不同区域的生态环境指数均大于经济发展指数。省会城市、沿江江南地区耦合协调度高于江淮之间和淮河以北地区。工业"三废"排放量、环境质量、环境污染治理力度是影响经济发展与生态环境耦合协调度的重要因素,建议通过改善这些方面进一步提升经济与环境的耦合协调度水平。 相似文献
79.
对北京中央电视塔周围25 km2区域电磁环境质量分别进行了射频的网格法手工监测和车载巡测自动监测,通过SPSS软件等对两种监测方法获取的数据进行了统计对比分析,发现两组数据在总体水平及数值分布特征上较为接近,因此车载巡测监测可以替代网格法监测。以车载巡测数据为基础,绘制了实测数据的道路电磁地图,利用插值法绘制了区域电磁地图,对区域电磁环境质量进行了直观表征。从回应公众关注和城市电磁规划出发,建议今后可利用车载巡测监测加强时域和频域的监测。 相似文献
80.
乌鲁木齐市与北方四城市的空气污染对比及原因分析 总被引:6,自引:1,他引:6
根据乌鲁木齐、兰州、太原、石家庄和北京五大北方城市的空气污染特征,结合各城市人口、经济和地理位置等要素,分析了乌鲁木齐市与其它城市空气污染及成因的主要异同点,对目前乌鲁木齐市大气污染治理中的若干问题进行了探讨。 相似文献