To the Problem of Bioindication of Oil Pollution of Freshwater Limnic Ecosystems Using Zooplankton on the Example of Lake Samotlor (KhMAO)

Water Resources - It is shown that the presence of petroleum hydrocarbons in water may have both a depressing and a stimulating effect on the development of certain species of zooplankton. The...     

淡水沉积物环境质量基准差异分析

对现有淡水沉积物环境质量基准进行了分类比较,通过对各种基准不同污染物的基准低值、基准高值以及灰色区域的对比分析,探讨现有基准间存在的差异以及造成差异的原因.结果表明,现有各基准低值和高值问分别存在2倍到15倍,4倍到29倍的较大差异,各基准均存在较大的灰色区域.造成差异的原因主要是影响污染物生物有效性因素的复杂性,以及基准建立方法的不确定性等.     

Assessment of the Trophic State of Lake Ladoga Tributaries and the Neva River by Phytoplankton

The results of investigations carried out in May, July, September, and November 2000 and 2001 are used to analyze the species composition and biomass structure of phytolankton of 13 tributaries of Lake Ladoga and the Neva River and assess the trophic state of the rivers and their saprobity.     

Assessment of the Similarity of Model and Parent Ecosystems Based on Data of Fresh Water Remote Monitoring

The physical conditions at which a model ecosystem in an artificial aquatic ecosystem is still similar to the parent ecosystem are considered. A similarity criterion for the parent and model ecosystems is created based on optical data. An experimental proof is given for the fact that the optical characteristics of a model ecosystem that has not been subjected to anthropogenic load remain similar to those of the parent ecosystem for several weeks. It is shown that the optical characteristics of polluted artificial ecosystems can be assessed from the spectra of the brightness coefficients of the upward irradiance from water.     

太湖流域地表水资源分质评价及水质型缺水形势分析

太湖流域水资源供需矛盾主要体现为"水质型缺水"问题,如何对"水质型缺水"进行定量描述,在太湖流域是一个难题.本文提出了"分质水资源量"的概念,以流域水资源四级分区为单元,以分区水质监测资料结合水资源量进行分析,分别统计分区分质水资源量.分析表明:太湖流域142×10⁸ m³的地表水资源量中,Ⅲ类以上的适合于饮用水源和一般工业用水的优质水为35.8×10⁸ m³,占25.2%;适合于电力冷却用水、农业灌溉的Ⅳ-Ⅴ类水为46.4×10⁸ m³,占32.6%;不可利用的劣Ⅴ类水有59.9×10⁸ m³,占42.2%.流域内优于Ⅴ类(含Ⅴ类)的地表水资源量为82.2×10⁸ m³,占地表水总资源量的57.8%.而浅层地下水己基本被污染.需要指出,Ⅰ-Ⅲ类优质水虽仍有35.8×10⁸ m³,但目前流域内对Ⅰ-Ⅲ类水的需求量己达60.6×10⁸ m³,如将此两数对比,则优质水缺额为24.8×10⁸ m³,但实际上,优质水的需求主要集中在流域中下游,而可供优质水水源则主要集中在流域上游地区山区水库和中游太湖湖心区、东部湖区和太浦河,供需两者的空间分布有较大出入,因此优质水资源缺额将更大,由此可见太湖流域水质型缺水形势十分严峻.     

Quality Assessment of Atmospheric Motion Vectors Over the Indian Ocean

Because conventional observations over the oceans are not available, especially during tropical cyclones, multi-spectral atmospheric motion vectors (AMVs) estimated from geostationary satellites are routinely assimilated in the numerical weather prediction models at different operational centres across the globe. The derived AMVs are generally validated with radiosonde observations available over land at synoptic hours; however, over the ocean there is a limited scope to assess the quality of AMVs. Over ocean, AMVs can be validated with radiosonde data available from opportunistic ships or using dropsonde data available from aircrafts. In this study, the accuracy of the AMVs derived from the geostationary satellites Kalpana-1 and Meteosat-7 is evaluated over the oceanic region. Radiosonde data available from a ship cruise held in the Bay of Bengal during the period 09 July–08 August 2012 and from the Cal/Val site situated at Kavaratti Island (72.62°E, 10.57°N) in the southern Indian Ocean are used to assess the AMV accuracy. In this study, 83 radiosonde profiles are used to validate the Kalpana-1 AMVs, to allow a better understanding of AMV errors over the Indian Ocean. The RMSVD of Kalpana-1 AMVs for the high-, mid- and low-levels are found to be 7.9, 9.4 and 5.3 m s^?1, respectively, while the corresponding RMSVD for Meteosat-7 AMVs are 9.1, 5.5 and 3.7 m s^?1. A similar accuracy is observed when the AMVs are validated against the NCEP analyses collocated with the nearest radiosonde locations. The high RMSVD and bias for Kalpana-1 AMVs at the mid-level and Meteosat-7 AMVs at the high-level are associated with the limitation of satellite winds to resolve the upper-level easterly jet in conjunction with errors in the height assignment. This study could help the numerical modellers to assign appropriate observation error over this region during the assimilation of AMVs into the NWP models.     

西伯利亚水库和叶尼塞河中物质及生态系统条件的预测：生物物理方法

An avenue to integrate theoretical, experimental and field research methods to forecast water quality in water bodies for different scenarios of water management is proposed. Exploration of the laws of organization, stability and controllability of laboratory "ideal" water microbial communities (model ecosystems) is the basis to build the following biophysical research chain:to formalize with primary field information a conceptual block-diagram of a water ecosystem →to real chemical and other density-dependent and population-growth-controlling factors → to find our limiting factors for natural ecosystems → to conduct experiments with isolated chemical factors and hydrobionts to derive kinetic dependencies and quantitative parameters→ to transfer regularities of operation and kinetic dependencies to the natural ecosystem→ retrospective verification of the model on the base of available field and derived theoretical-experimental data →prognostic calculations for the scenario. Efficiency of the approach is demonstrated in microalgal "blooming" models for Krasnoyarsk and Kantat reservoirs and in prognostication of radioecological state of great Yenisei river:1) radionuclide distribution in the Yenisei''s bottom sediment is nonuniform-"spotty"; 2) it is theoretically shown, that due to biological interactions and tro-phical radioniclide migration there is "spotive" type of space radionuclide distribution. The research is to make use of the novel methods of ecological biophysics:Monitoring:spectral analysis of surface waters (algal pigments), fluorescent techniques to evaluate productivity and condition of algae; rapid bioassays for water toxicity (bioluminescence, chemotaxis techniques). Kinetic experiments:microcosms on evaluating self-purification rates; special cultivators to evaluate the rates of growth of hydrobionts and radioactive engulfing, nutrition spectra; methods of finding growth limiting factors. Models:application of Bellman Principle to optimizing the river water use; theory and peculiarities of microbiological decomposition of pollutants in the river ecosystem. The composition of Prognostication Simulation Model is the next:1) hydrodynamical unit to calculate 2-dimensional space-time rate of stream on any depth; 2) hydrophysical unit to calculate:water temperature and level of solar radiation inside the water body; 3) ecosystem unit to calculate dynamic of concentration of phytoplankton, zooplankton, bacteria, major chemical matters and pollutants in water, content pollutants inside of hydrobionfs cells and dynamic of bentos; 4) radioe-cological unit to forecast the dynamic of radionuclides in the water body and bottom, their hydro-bont''s concentration; 5) database. Reservoirs and river models are provided by monitoring and kinetic experiments data.     

Assessment of Anthropogenic Impact on Marine Ecosystems and Biological Resources in the Process of Oil and Gas Field Development in the Shelf Area

Current methodology of environmental impact assessment in connection with the environmental consequences of hydrocarbons production in the shelf area is analyzed. Basing on the ecosystem approach, a scheme of environmental impact estimates is suggested, envisaging the use of a set of gradations (scales) to characterize spatial and temporal scope of impacts and their consequences, as well as criteria (thresholds) of impact permissibility, taking into account the natural variability in the population and ecosystem parameters. Estimates of the environmental and fishery-related consequences of hydrocarbon production in the sea shelf area at different stages of the process are compared to the available measured and calculated data. The suggested scheme of environmental impact assessment and criteria of permissible impacts are recommended for expert analysis, forecasting, and monitoring of the environmental situation in the sea shelf areas of Russia under the conditions of anthropogenic impact.     

Assessment of the Present State and Future Fate of River Saraswati,India: Water Quality Indices and Forecast Models as Diagnostic and Management Tools

Water quality assessment is key to the conservation and management of rivers. River Saraswati, a distributary of the river Ganga, serves as a lifeline to many villages in the district Hooghly in West Bengal, India. As the river is gradually dying due to diverse man-made pollution, ten water quality parameters in two sampling spots (PR-1 and PR-2) in the river are monitored month-wise from March 2017 to February 2020,  and these are compared with those from a reference pond. The water quality index (WQI) is determined for the two riverine spots and the reference pond based on the Canadian Council of Ministers of Environment WQI (CCMEWQI) and weighted arithmetic WQI, respectively. In addition to actual observations, three different forecasting methods, exponential smoothing, autoregressive integrated moving average, and artificial neural network, are used to predict WQI for the next two years. This study indicates that free CO₂, dissolved oxygen, and turbidity are the key parameters to evaluate this river's anthropogenic stress and health. The actual and forecasted results reflect the precipitous degradation of CCMEWQI in PR-2. Therefore, the immediate intervention of all stakeholders is required to adopt an integrated and comprehensive river management plan to save the river from utter obliteration.     

Mesocosm-Based Estimation of the Consequences of Complex Contamination of a Freshwater Body by Metal Salts

The dynamics of metal concentrations in the solution, suspension, sediments, and floating plants, as well as functional and structural parameters of phytoplankton and zooplankton were studied. The sorption rate of metals on suspension and the efficiency of their removal into bottom sediments decreased in the series Pb > Cu > Zn > Cd and at increasing proportion of metal aquaions in the solution. The effect of intensive renascence of green algae was recorded from the eighth to tenth day after the metal discharge into the mesocosms. This effect activated a plankton mechanism of metal removal into bottom sediments. The metal discharge led to a strong and stable depression in all groups of zooplankton.     

Dynamics of Morphofuncitonal Groups of Phytoplankton in the Rybinsk Resrevoir and Assessment of the Resevoir Water Quality by the Community Index

Water Resources - The changes in the ratio of species representing different morpho-functional groups, identified by physiological, morphological and ecological parameters [29] were analyzed based...     

Contamination of port zone sediments by metals from Large Marine Ecosystems of Brazil

Sediment contamination by metals poses risks to coastal ecosystems and is considered to be problematic to dredging operations. In Brazil, there are differences in sedimentology along the Large Marine Ecosystems in relation to the metal distributions. We aimed to assess the extent of Al, Fe, Hg, Cd, Cr, Cu, Ni, Pb and Zn contamination in sediments from port zones in northeast (Mucuripe and Pecém) and southeast (Santos) Brazil through geochemical analyses and sediment quality ratings. The metal concentrations found in these port zones were higher than those observed in the continental shelf or the background values in both regions. In the northeast, metals were associated with carbonate, while in Santos, they were associated with mud. Geochemical analyses showed enrichments in Hg, Cd, Cu, Ni and Zn, and a simple application of international sediment quality guidelines failed to predict their impacts, whereas the use of site-specific values that were derived by geochemical and ecotoxicological approaches seemed to be more appropriate in the management of the dredged sediments.     

The State of Benthic Communities and Water Quality Evaluation in the Cheboksary Reservoir

Present-day quantitative and qualitative characteristics of the Cheboksary Reservoir have been investigated, and data on the biological diversity of benthic organisms have been compared to those of hydrobiological studies carried out in the region prior to the reservoir construction. The reservoir bottom communities include 75 species and forms of benthos. The reservoir water quality has been evaluated using different methods, including the determination of the degree of morphological structure abnormalities in chironomid larvae, regarded as sublethal indicators of bottom sediment pollution with toxic substances.     

Quality Assessment of Southeast Nile Delta Groundwater for Irrigation

The Nile Delta aquifer has deteriorated in the quality of the groundwater due to domestic, agricultural and industrial activities. In order to examine this, a dataset of thirty-one shallow groundwater samples and four surface water samples were collected in May 2014. The objective of our study is to investigate the hydrochemical characteristics of the groundwater at El-Khanka region in El-Qalubia governorate, southern Nile Delta to discuss the possibility of groundwater use for agricultural purpose. Groundwater types were defined, and the suitability for use in irrigation was evaluated. The factor analysis was conducted to investigate the relationship between the thirteen variables for exploring the loading of them in the model. Then, the principal component analysis was performed to identify the linear combination of variables that account for the greatest amount of common variance. Results showed that groundwater samples are mainly alkaline with an average pH value of 8.60. The total dissolved solids (TDS) range from 350 to 1456 mg/L. The highest concentrations of the anions and cations are sulfate (\(\rm{SO}_4^{2-}\)) and sodium (Na⁺) respectively. The residual sodium carbonate (RSC) is less than 1.25 meq/L. Also, all groundwater samples are located in good and permissible salinity with TDS < 1500 mg/L. In addition, all samples are located in the low sodium hazard zone where sodium adsorption ratio (SAR) is less than 10. Therefore, it is concluded that, the groundwater is suitable for irrigation use in El-Qalubia Governorate. Four factors with Eigenvalues above 1.0 which correlated to each other contributed to the model with 81% of the total variance and governed the spatial variability of the aquifer.     

用标定方法检测地震计的异常状态

以浙江省测震台网部分台站地震计为研究对象,选取一定时间窗口对阶跃标定波形进行计算,得出地震计在该时段内的周期和阻尼变化情况。结合台网台站运行维护工作,经过统计分析,表明利用此方法能够在一定程度上反映出台站地震计运行的异常状态。     

Quality Assessment of the Cobel-Isba Numerical Forecast System of Fog and Low Clouds

Short-term forecasting of fog is a difficult issue which can have a large societal impact. Fog appears in the surface boundary layer and is driven by the interactions between land surface and the lower layers of the atmosphere. These interactions are still not well parameterized in current operational NWP models, and a new methodology based on local observations, an adaptive assimilation scheme and a local numerical model is tested. The proposed numerical forecast method of foggy conditions has been run during three years at Paris-CdG international airport. This test over a long-time period allows an in-depth evaluation of the forecast quality. This study demonstrates that detailed 1-D models, including detailed physical parameterizations and high vertical resolution, can reasonably represent the major features of the life cycle of fog (onset, development and dissipation) up to +6 h. The error on the forecast onset and burn-off time is typically 1 h. The major weakness of the methodology is related to the evolution of low clouds (stratus lowering). Even if the occurrence of fog is well forecasted, the value of the horizontal visibility is only crudely forecasted. Improvements in the microphysical parameterization and in the translation algorithm converting NWP prognostic variables into a corresponding horizontal visibility seems necessary to accurately forecast the value of the visibility.