Prediction of the fate of radioactive material in the South Pacific Ocean using a global high-resolution ocean model

We investigate the release of radioactive contaminants from Moruroa Atoll in a global high-resolution off-line model. The spread of tracer is studied in a series of simulations with varying release depths and time-scales, and into ocean velocity fields corresponding to long-term annual mean, seasonal, and interannually varying scenarios. In the instantaneous surface release scenarios we find that the incorporation of a seasonal cycle greatly influences tracer advection, with maximum concentrations still found within the French Polynesia region after 10 years. In contrast, the maximum trace is located in the southeast Pacific when long-term annual mean fields are used. This emphasizes the importance of the seasonal cycle in models of pollution dispersion on large scales. We further find that during an El Ni?o/Southern Oscillation (ENSO) event reduced currents in the region of Moruroa Atoll result in increased concentrations of radioactive material in French Polynesia, as direct flushing from the source is reduced. In terms of the sensitivity to tracer release time-rates, we find that a gradual input results in maximum concentrations in the near vicinity of French Polynesia. This contrasts the instantaneous-release scenarios, which see maximum concentrations and tracer spread across much of the South Pacific Ocean. For example, in as little as seven years radioactive contamination can reach the east coast of Australia diluted by only a factor of 1,000 of the initial concentration. A comparison of results is made with previous studies. Overall, we find much higher concentrations of radionuclides in the South Pacific than has previously been predicted using coarser-resolution models.     

Heterotrophic Nano- and Microplankton under Conditions of Anthropogenic Eutrophication of the Bay of Novorossiisk

Seasonal and long-term dynamics of heterotrophic plankton in the Bay of Novorossiisk are discussed. It is shown that specific variation in the biomass of nanoheterotrophs and infusoria is associated with the processes of anthropogenic water eutrophication. The biomass of infusoria has increased ten times and that of zooflagellates two times since 1985–1986. Infusoria of the genera Strombidium, Strobilidium, and Mesodiniumare dominant in the protozoan plankton. The annual average level of Oligotrichadevelopment in the bay is characteristic of eutrophic water bodies (112–417 mg/m³); in the spring–summer season, however, it may increase to 500–1034 mg/m³. In the part of the bay near the port, which is exposed to a strong anthropogenic impact, the biomass of ciliate protozoa can reach 2 g/m³.     

Population cycles of the bank vole in the range optimum

Patterns of seasonal and long-term dynamics of the size and structure of the bank vole population were studied in the European subtaiga subzone, the optimum of the species range. The dynamics of this population proved to undergo complex fluctuations with cyclic components, which have periods of one year and about three years. The one-year fluctuations of the population size and structure are accounted for by animal adaptation to seasonal changes in environmental factors. The fluctuations with the three-year quasi-period are determined by intrapopulation density-dependent mechanisms.     

区域二氧化硫控制优化模型研究

传统的区域二氧化硫控制优化都是基于损害函数法和环境标准化法的。本文在分析比较了传统二氧化硫污染控制战略优化中的损害函数法和环境标准化法各自的优点与局限的基础上。建立了基于时间序列决策的整数规划优化模型。这一理论模型更好地描述了控制战略实施的过程。把时间作为模型优化的一个因子。这种基于时间序列的过程充分考虑了货币的时间价值。并能分析这些时间价值对二氧化硫污染控制战略的动态过程影响。本文的模型是更加符合现实的情况。它对于区域二氧化硫控制的中长期决策优化显得更为有效和准确。     

The role of environmental and fisheries multi-controls in white seabream (Diplodus sargus) artisanal fisheries in Portuguese coast

Evaluating the effects of fishing and environmental factors on fish populations are fundamental tenets of fisheries science. In this study, we assess associations between environmental variables (sea surface temperature; North Atlantic Oscillation index; upwelling; wind magnitude; westerly winds; northerly winds; river discharge) and fishing variables (fishing effort) in Diplodus sagus catch rates accounting for regional analyses (northwest coast; southwest coast and Algarve—Algarve south coast). Different time series models for data fitting (multi-model approach) were used. The models were lagged, according to species fishing recruitment age based on the hypothesis that fisheries catches depend on larvae recruitment and survivorship. D. sargus catch rates across areas were unrelated to fishing effort but correlated to environmental variables, with seasonal events explaining much of the variability in trends. On the northwestern coast, the catch rates were mainly set by sea surface temperature (SST) and wind magnitude; however, southwestern coast catch rates were set by NAO winter. On the south coast, only one statistical model (SST, upwelling and westerly winds) associated spring conditions with D. sargus catch rates. The multi-model approach revealed autumn, winter and spring seasonal effects to be related with northwest, southwest and Algarve coastal catch rates, respectively, indicating a possible coastal longitudinal gradient related with given periods of spawning and larval availability. The metadata analysis yielded different results from the regional analyses. In summary, marine resource management should take regional environment characteristics and variability into account when determining sustainable catch rates in given areas for species with high habitat site fidelity.     

Patterns of the accumulation of chemical elements in the plankton of a fresh water body

For the first time, comparative data are presented on the distribution of 70 chemical elements occurring in the Beloyarsk Reservoir between the water and the plant and animal components of the plankton (phyto- and zooplankton). All these elements are ranked into groups according to the values of accumulation coefficient (AC) for phytoplankton and zooplankton. For the sum of all chemical elements, a significant positive correlation has been revealed between their content in the water and in the plankton. It has been shown that elements with even atomic numbers and concentrations in the plankton below 7 ??g/g dry weight are accumulated by the plankton in significantly larger amounts than such elements with odd atomic numbers. This fact confirms the classic concept developed by A.P. Vinogradov that the prevalence of chemical elements in the biosphere depends on their position in the periodic system.     

太湖流域1954~2006年气候变化及其演变趋势

用Mann Kendall统计检验方法对太湖流域6个气象站点1954~2006年降水、气温、相对湿度、日照时数的变化趋势和时空特征进行了分析,结果表明：50余年来太湖流域降水量呈较弱的增加趋势,冬季和夏季降水增加显著;空间变化趋势表现为北部地区降水量呈下降趋势,东南部地区呈上升趋势。年平均相对湿度表现为微弱的下降趋势,M K倾斜度值为 -099%/10 a;春、秋季相对湿度都显著减小,而夏季减小幅度较弱,冬季减小现象不显著。年平均气温呈现明显上升趋势,并表现出最低气温比最高气温增高趋势显著的特点,冬、春季增温显著;空间分布变化趋势为以平湖和溧阳为中心的两个地区上升趋势最小,以上海为中心地区上升幅度较大。年日照时数的下降趋势幅度较大,以溧阳为中心的西部地区最为明显,四个季节日照时数都呈减少的趋势;空间分布变化趋势表现为全流域呈减少趋势,由西向东减少幅度依次减小。气候变暖,降水将进一步增加,必然导致径流也呈增加趋势,在一定程度上加大了太湖流域洪涝灾害发生的可能性。分析成果有助于进一步研究气候变化对太湖流域水资源和防洪安全的影响,也将为太湖流域未来气候变化情景的构建提供科学依据。     

Kinetics of the adsorption and desorption of radionuclides of Co, Mn, Cs, Fe, Ag and Cd in freshwater systems: experimental and modelling approaches

The sorption and release kinetics of 54Mn, 58Co, 59Fe, 109Cd, 110mAg and 134Cs by freshwater suspended particles were investigated to better identify the biogeochemical processes involved and to obtain suitable data for improving models describing radionuclide migration in freshwater streams. In order to observe any seasonal variability in the interaction of radionuclides with natural particles, experiments were performed both in winter and in summer during a phytoplanktonic bloom. Two kinetic models are compared in this paper: the "one-step reversible" model, based on the hypothesis that the transfer of radionuclides between water and suspended solids is governed by a reversible reaction, and the "two-successive-step reversible" model, which assumes two distinct types of sites or reactions on the solid phase. The "one-step reversible" model is generally unable to describe properly the exchange kinetics; this result shows that at least two processes are generally involved in radionuclide exchange between water and suspended particles. On the contrary, a model involving the existence of two successive reversible reactions properly simultes both the sorption and release kinetics. The determination of the kinetic coefficients allows quantitative assessment of the relative importance and kinetics of the processes. In particular, it has been shown that, except for Cs and Cd, major fractions of the radionuclides are associated at equilibrium with particulate sites involving strong interactions. The kinetics to reach this equilibrium depend on seasonal conditions, especially for Co and Mn: the transfer of Co and Mn to particulate sites involving strong interactions is much slower in winter. The distribution of the radionuclides between water and particulate sites involving weak interactions also shows seasonal variations for Co, Mn, Fe and Ag: the capacity to associate radionuclides is much higher in summer for Co and Mn, while the inverse tendency is observed for Fe and Ag. For Cs and Cd, no significant seasonal differences were observed.     

Reconstruction of 137Cs signal in Cuba using 7Be as tracer of vertical transport processes in the atmosphere

Levels of 137Cs and 7Be in aerosols have been measured in the region of Cienfuegos (Cuba) during the period 1994-1998. 137Cs showed the same seasonal trend as 7Be and the monthly regimes of precipitation seemed to be responsible for the observed pattern. The 137Cs/7Be ratio obtained in Cienfuegos and Miami (FL) in this period was used to calibrate the long-term database of 137Cs concentrations recorded in Miami (250 km from Cienfuegos). The database was then employed to reconstruct the 137Cs monthly concentrations in Cienfuegos since 1957.     

Increasingly warm summers in the Euro–Mediterranean zone: mean temperatures and extremes

The recent increase in European temperatures led to a strong enhancement in the occurrence of extremely warm events, with relevant consequences for environment and everyday life. Here, we investigate the evolution of very intense warm and cold events in a south-western European zone during 1961–2007 at a seasonal level. Special attention is given to summertime when warming is the most pronounced. Using a previously developed theoretical model, we discuss how the average properties and long-term trends observed in probability density functions of daily temperatures can explain changes in the frequency of severe, isolated events. In this perspective, the recent intensification of extremely warm events, especially experienced by the Mediterranean zone, is proved to be well consistent with a pure shift of seasonal mean temperatures. On the other hand, any change in the second and higher distributional moments of daily temperatures is ruled out by the data, whereas the average values of these properties, that is, variability and asymmetry, do play a role by shaping the temporal behavior of very intense events.     

Coat color polymorphism in populations of the northern mole vole in the Ural Region

Collections made in the course of long-term field studies on ecology of the northern mole vole Ellobius talpinus Pall. in the Ural Region and neighboring areas (more than 2000 individuals from 24 points of the species range) were used to analyze geographic variation in its coat color (color morphs). On the basis of long-term observations (1985–1999) on marked animals from a polymorphic population (Kurtamyshskii raion, Kurgan oblast), the life spans of males and females and the dependence of life span on population density and structure were estimated in animals of different color morphs. Each color morph of E. talpinus was shown to have specific features of the seasonal dynamics of age structure and migrations.     

Radioecological Studies on the Plankton of the Cooling Water Reservoir of the Beloyarsk Nuclear Power Plant

In the zone of heated water discharge and at the control site of the Beloyarsk Reservoir, the phytoplankton was characterized by dominance of blue-green, green, and pyrrophyte algae, and the zooplankton, by the prevalence of crustaceans over rotifers. The study sites differed in the species and quantitative composition of the dominant complex, but the total abundance and biomass of the phytoplankton in the heated zone and the control site did not differ significantly. In Teplyi Bay, the zooplankton was inhibited, which was manifested in the decrease of its abundance and biomass by four and seven times, respectively, in comparison with the control. Radionuclide concentrations in the plankton of the cooling reservoir in the period between 1986 and 1988 were determined. It was found that radionuclide concentration in the plankton is higher in the zone of heated water discharge than beyond it.     

基于MODIS AOD数据的南京市大气能见度估算

以南京市为研究区,利用MODIS气溶胶产品数据(MOD04L2)获取研究区气溶胶标高数据,结合地面气象站点能见度观测数据,构建研究区不同季节能见度估算模型,估算南京市2013年能见度时空分布。研究结果表明,研究区能见度模型估算值与实测值总体趋势较为一致,分季节模型能见度估算均值相对误差为14.3%;南京市2013年能见度年均值为6.07km,大致呈现出由市区向周边郊区逐渐升高的趋势;研究区不同季节能见度差异明显,夏季能见度显著高于其他3个季节,在该季节全市能见度均值达到9.93km,约为其余3个季节均值的2倍左右,气候状况与经济社会发展布局是影响研究区能见度时空差异的主要因素。     

Treatment of uncertainty and developing conceptual models for environmental risk assessments and radioactive waste disposal safety cases

The common approach to performing quantitative risk assessments in the contaminated land industry in the UK lacks a formal methodology for the treatment of the full range of uncertainties and for documenting decisions regarding the development of conceptual models and the selection of computer codes. The approach presented here represents an alternative, more detailed, and systematic approach for developing conceptual models and addressing uncertainties when undertaking contaminated land risk assessments. It is intended that the advantages of this approach are recognised by practitioners in the contaminated land industry and adopted, where appropriate, to help improve the quality of contaminated land risk assessments. The identification of features, events, and processes (FEPs) has been applied to safety assessments of deep geological and near-surface disposal of radioactive wastes. One of the primary benefits of using this approach is in the development of conceptual models. The approach identifies the FEPs that need to be addressed during the development of conceptual models and in the selection of suitable computer codes that can be used to represent the conceptual models. This approach has been applied by BNFL at the low-level radioactive waste disposal site at Drigg in Cumbria and is currently being adopted for a contaminated land study at the Sellafield site, also in Cumbria. This paper presents the advantages of using FEPs in the development of conceptual models and the treatment of uncertainties. The paper also discusses the application of this approach to contaminated land studies and provides an example to demonstrate the application of the approach. BNFL's approach at the Drigg site involves the identification of components (features) and phenomena (events and processes) that govern interactions and dependencies between the components by arranging them in a matrix format.     

Multi-objective design optimization of sustainable commercial a-ircraft: performance and costs

The present work deals with a multi-objective optimisation approach to incorporate up-to-date financial models in the multidisciplinary conceptual design of a commercial aircraft. Design optimisations based on financial objective functions are compared to standard performance-based optimal solutions. The main novelty is in the extension of the financial models to the long-term investments of a wider group of stakeholders. The rationale underlying this research stems from two considerations: (i) the environmentally sustainable development of the air transportation system in the next 20 years is subordinate to breakthrough technologies, since the consolidated ones have reached their saturation point; (ii) the economic impacts of highly innovative concepts on the stakeholders chain is still uncertain. The problem is addressed at the conceptual design level and the analysis is performed within a comprehensive multidisciplinary framework, adopting all the technical constraints required in aeronautical design. The Pareto fronts obtained using performance and financial merit factors, reveal that the proposed financial model yields highly efficient, technically sound concepts. The design space point corresponding to the negative cash flows minimum turned out to be very close to the one corresponding to minimum acoustic emissions, confirming that the financial model drives the optimiser towards environment-friendly designs.     

Adaptive responses of scots pine to the impact of adverse abiotic factors on the rhizosphere

The impact of long-term seasonal soil freezing, drought, and waterlogging on the rhizosphere of young Scots pine trees (Pinus sylvestris L., age class 1) has been simulated in experiments. The results have shown that cold stress exposure leads to reduction of the rates of linear and radial tree growth and of chlorophyll content in needles, a shift in the peak of starch content, and initiation of free amino acid deposition in the aboveground plant parts. Drought activates utilization of carbohydrate reserves and amino acid accumulation in the root bast, whereas soil waterlogging stimulates deposition of carbohydrates but causes a decrease in the levels of chlorophyll and amino acids in all plant tissues.     

Changes in plankton abundance, biomass, and chemical composition under the influence of the cooling system of the Beloyarsk Nuclear Power Plant

The abundance and biomass of phytoplankton and zooplankton proved to noticeably decrease after the water passed through the cooling system of the Beloyarsk Nuclear Power Plant: the phytoplankton perished by 38% (65 metric tons per day), and the zooplankton, by 55% (6 t/day). In the period between 1985 and 1991, the concentration of⁶⁰Co in the plankton of water intake and discharge canals varied from 120 to 1400 Bq/kg dry weight, and that of¹³⁷Cs, from 150 to 1040 Bq/kg dry weight, which is commensurable with the content of radionuclides in the plants and grounds of the Beloyarsk reservoir. In 1985, it was noted that the plankton passing through the cooling system of the nuclear power plant became enriched with Ca, Fe, Mg, Mn, Co, Cs, Cu, Mo, Ni, Pb, Si, Sn, Ti, V, and W.     

基于ARIMA和BP神经网络组合模型的我国碳排放强度预测

预测我国碳排放强度的长期变动趋势, 对国家进行宏观经济管理和节能减排工作具有重要的参考价值。运用深入分析自回归移动平均模型和神经网络的特性,并在此基础上建立ARIMA模型和BP神经网络组合模型,将碳排放强度的时间序列的数据结构分解为线性和非线性残差部分,对我国碳排放强度的变化趋势进行了综合分析与预测。结果显示:今后10 a我国碳排放强度总体是逐步下降的,但到2020年我国碳排放强度仅比2005年下降34%,比我国政府提出碳排放强度下降40%~45%的目标还有一定的差距。因此,要在2020年实现我国碳排放强度目标,必须要调整宏观经济政策,采取各种政策措施以实现目标     

Laboratory and field studies of polonium and plutonium in marine plankton

Uptake experiments were successfully undertaken for polonium and plutonium in the marine diatom Skeletonema costatum. Experiments were complemented with a field study which yielded concentration factors for these radionuclides for plankton samples collected in the eastern Irish Sea.     

长江流域月降水的EEMD多时间尺度遥相关分析

基于长江流域138个气象站1961~2016年的逐月降水观测资料,应用集合经验模态分解（EEMD）方法,分别对各站点的月降水序列进行EEMD分解,然后,运用时滞相关分析和逐步变量选择的方法,以识别长江流域月降水周期振荡和长期趋势的显著影响因子,并构建多元线性回归模型对长江流域月降水进行预测。结果表明：（1）近50多年来,长江流域各站点的月降水呈现出显著的季节、年际和年代际尺度振荡特征。（2）流域内各站点月降水的长期变化趋势存在着较大的空间差异性,表现为金沙江、雅砻江、大渡河以及鄱阳湖流域是月降水长期趋势显著增加的集中区,而岷江中游以及洞庭湖流域的南部是月降水长期趋势显著减少的集中区。（3）厄尔尼诺1+2区的平均海表温度（NINO1+2）的过去模式是影响长江流域月降水周期振荡的主要气候因子,而全球平均气温距平（GlobalT）是影响长江流域月降水长期趋势的主要气候因子。（4）基于已识别的影响因子构建的月降水量预测模型在旱季的预报性能高于雨季,并在长江上游地区的预报性能高于其中下游地区。