Search for hidden pearl mussel populations at the Russian section of the Baltic Sea     

《Limnologica》2019

The freshwater pearl mussel Margaritifera margaritifera (L., 1758) is considered to be a critically endangered species. It is important to obtain information on the distribution and status of the surviving populations of the species, but in Russia this work is still problematic due to the size of the country’s territory, combined with the insufficient number of available specialists. “Searching rules” have been proposed to remotely identify potential pearl mussel habitats in rivers. The most important criteria are relating to the lakes found at the rivers’ sources, as well as to the extent of the deforestation along river basins. About 200 watercourses of the Russian section of the Baltic Sea basin were evaluated using these “rules”. As a result, two previously unknown, viable populations were discovered (comprising about 53,000 specimens), while the absence of pearl mussels was made evident among some rivers which were traditionally believed to be their habitats. The obtained data provides an update on the status of pearl mussels in Russian territories located south of the 61 st degree of latitude. There are 10 populations of this species; 4 of them are almost extinct, 6 are relatively numerous but declining. The total number of pearl mussels hardly exceeds 90,000 individuals.  相似文献   

气候变化对长江上游径流影响预估     

秦鹏程  刘敏  杜良敏  许红梅  刘绿柳  肖潺 《气候变化研究进展》2019,15(4):405-415

利用第五次国际耦合模式比较计划(CMIP5)中5个气候模式在3种典型浓度路径(RCPs)下的预估结果驱动SWAT水文模型,预估了21世纪气候变化对长江上游年径流量、季节分配以及极端径流的影响。结果表明：预估的长江上游平均气温呈显著上升趋势,21世纪末较当前(1986—2005年)升高1.5~5.5℃,降水总体呈增加趋势,在21世纪30年代后高于当前气候平均值,21世纪末相对于当前增加5%~15%。流域内气候变化存在明显空间差异,金沙江和岷沱江流域气温升高和降水增加幅度均大于流域平均值。预估的长江上游年径流量及各月平均径流均有增加趋势,在21世纪30年代后高于当前多年平均值,21世纪中期增加4%~8%,21世纪末增加10%~15%。预估的径流年内分布的均匀性有所增加,但年际变化明显增大,极端旱涝事件的频率和强度明显增加。预估的各子流域径流变化对气候变化的响应也存在差异,金沙江和岷沱江流域年径流量、年际变化和年内分布变化小,对气候变化的响应表现为低敏感;嘉陵江流域、乌江流域和长江上游干流径流增加幅度大,同时极端丰枯出现的频率和程度增加显著,是气候变化响应的敏感区域。  相似文献   

http://www.sciencedirect.com/science/article/pii/S1674987111000752   总被引：2，自引：0，他引：2  

Jiansheng Shi  Zhao Wang  Zhaoji Zhang  Yuhong Fei  Yasong Li  Feng’e Zhang  Jingsheng Chen  Yong Qian 《地学前缘(英文版)》2011,2(4):593-598

A series of environmentalegeological problems have been caused by over-exploitation of deep groundwater (i.e., confined aquifer water) in the North China Plain. In order to better understand the status of deep groundwater over-exploitation and the resultant environmentalegeological problems on a regional scale, the over-exploitation of groundwater has been assessed by way of the groundwater exploitation potential coefficient (i.e., the ratio of exploitable amount of deep groundwater to current exploitation), cumulative land subsidence, and long-term average lowering rate of the groundwater table. There is a good correlation among the results calculated by the different methods. On a regional scale, deep groundwater has been over-exploited and there is no further exploitation potential under the current conditions. The groundwater exploitation degree index takes the exploitation in 2003 as the reference for the calculations, so the results mainly reflect the degree of current groundwater exploitation. The results of over-exploitation of deep groundwater obtained by land subsidence data and long-term average rate of depression of the water table mainly reflect environmentalegeological problems caused by exploitation of deep groundwater.  相似文献   

“Indicators of vulnerability and adaptive capacity”: Towards a clarification of the science–policy interface     

Jochen Hinkel   《Global Environmental Change》2011,21(1):198-208

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Phytoplankton,macrophytes and benthic diatoms in lake classification: Consistent,congruent, redundant? Lessons learnt from WFD-compliant monitoring in Poland     

《Limnologica》2016

The lake monitoring programme compliant with the Water Framework Directive has been implemented in Poland since 2007. Currently, the methods for three biological quality elements (BQEs): phytoplankton (the Phytoplankton Multimetric for Polish Lakes, PMPL), macrophytes (the Ecological State Macrophyte Index, ESMI) and phytobenthos (the Diatom Index for Lakes, IOJ) are officially applied and internationally intercalibrated. Based on the monitoring data from 256 lakes surveyed in 2010–2013 and assessed for all the three BQEs, we tested whether the assessment results obtained by the three biological methods were consistent and we searched for the causes of inconsistencies which we found. The lake classifications obtained from the PMPL and ESMI were highly consistent and the relationship between these metrics was relatively strong (R = 0.66, p < 0.001). Both metrics correlated equally strongly with water quality indicators. However, the PMPL and ESMI indicated systematic dissimilarities in the sensitivity to eutrophication between shallow and deep lakes. In shallow lakes, the alarming symptoms of macrophyte community deterioration (lower values of ESMI) occurred at lower nutrient and Chla concentrations and were accompanied by a better status of phytoplankton (higher values of PMPL) than in deep lakes that can be explained by a synergistic effect of inorganic suspended solids and algal growth on water transparency. As a consequence, the positions of phytoplankton and macrophytes as early warning indicators in the eutrophication gradient in shallow lakes were inverted compared to those in deep lakes. Compared to the PMPL and ESMI, the IOJ method gave the least stringent assessment results, with 22% of lakes failing to meet the environmental objectives. The relationships between IOJ and PMPL, and ESMI were relatively weak (R = 0.17, p = 0.008 and R = 0.17, p = 0.007, respectively). Moreover, the phytobenthos index IOJ correlated significantly more weakly with all the water quality indicators than either PMPL or ESMI did. The poor performance of the phytobenthos method in this study may suggest a limited indicator value of this BQE for lake assessment or inappropriate sampling design.  相似文献   

A prediction model for important mineral resources in China     

《Ore Geology Reviews》2017

Prediction models for mineral resources provide an analytical foundation and method to express the results of resource evaluations. The project “China National Mineral Resources Assessment Initiative” was conducted during 2006–2013, with the aim to determine the location, quantity, and quality of 25 important mineral resources occurring at depths of <1 km. There are currently 80 integrated prediction models on the scale of III–level metallogenic belts in use across China. The Huangshaping Pb–Zn polymetallic deposit, Hunan province, China, is used as a case study to establish methods and processes for developing a mineral resource prediction model that would be used for exploration targeting. The construction of prediction models requires the development of a classification scheme for the proposed prediction method appropriate for the prediction area. An initial metallogenic model is quantitatively transformed to a prospecting model, and then a prediction model. The incorporation of additional methodology, analysis of a comprehensive geological database, and correlation of asymmetric information between the well–explored typical deposit area and regional prediction area, yield an integrated prediction model. This paper also discusses the prediction modeling theory, and presents 12 models used for mineral assessments.  相似文献   

新疆尼勒克、巩留交界MS6．0地震灾害损失评估与房屋震害特征     

谭明  唐丽华  吴国栋  常想德  张勇  宋立军  李洋  李亦纲  王伟  石广岭  李志海 《内陆地震》2012,26(3):209-220

新疆尼勒克、巩留交界MS6．0地震震中烈度为Ⅶ度，地震没有造成人员伤亡，但个别民宅倒塌，大量村镇居民房屋遭受中等以上破坏，一些教育、卫生等公房遭破坏；交通和水利设施有一定程度破坏，经及时抢修，未对灾区生产生活产生明显影响。通过实地抽样调查和统计计算，评估出本次地震造成的直接经济损失为67846万元，恢复重建的经费需120349万元。  相似文献   

基于模糊综合评价模型的天津滨海新区湿地生态系统健康评价   总被引：3，自引：0，他引：3  

王秀明  李洪远  孟伟庆 《湿地科学与管理》2010,6(3):19-23

以环渤海地区的天津滨海新区湿地为例,运用模糊综合评价模型对湿地生态系统的健康进行了诊断评价。首先从湿地生态特征、整体功能特征和社会经济3方面选取26个评价指标,构建了天津滨海新区湿地生态系统健康的评价体系。评价等级分为很健康、健康、一般、一般病态、疾病5级,运用定量与定性相结合的方法界定等级。运用模糊综合评价模型对天津滨海新区湿地生态系统健康进行诊断,评价综合得分为0.48,健康水平处于疾病状态,主要表现在水质污染严重和水源保证水平低、景观破碎化、功能退化3个方面。  相似文献   

Temporal trend, spatial distribution, and terrestrial sources of PBDEs and PCBs in Masan Bay, Korea   总被引：1，自引：0，他引：1  

Sang Hee Hong 《Marine pollution bulletin》2010,60(10):1836-3908

Congener specific determination of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) was carried out in 21 surface sediment samples and a sediment core from Masan Bay, Korea. Among the 40 PBDE congeners targeted only 29 were detectable. PBDE congener profile within sediments was dominated by BDE-209 followed by BDEs-99, -47, -153 and -183, sequentially. In surface sediments, the average ΣPBDEs levels approached that of average ΣPCBs values. However, trends observed in the sediment core suggest that this pattern will alter over time and result in higher surface sediment PBDE concentrations than PCBs in future. Various diffuse and point sources for PBDEs and PCBs were identified in this location. Shipping and other industrial activities were associated with PCB contamination while domestic and industrial waste discharges corresponded with PBDE contamination. The average concentration for PBDEs and PCBs in surface sediments were 5.7, 7.2 ng/g dry weight, respectively.  相似文献   

Research and management priorities for Atlantic marine recreational fisheries in Southern Europe     

《Marine Policy》2017

Marine Recreational Fishing (MRF) is an important activity in Europe, with 9 million fishers and generating annually € 6 billion in direct expenditures. However, there is a lack of data and understanding of MRF in Europe, particularly in Southern countries, which prevents a number of fish stocks from being effectively assessed and managed. In November 2016, a participatory workshop on MRF was held in Vigo (Spain) to identify challenges and opportunities for data collection, and to diagnose key research gaps and management issues for MRF in the Southern European Atlantic. Experts from a wide range of disciplines (researchers, policy makers, fisheries managers and commercial and recreational fishers) highlighted that the management of MRF is a challenge due to complex and dispersed legal frameworks, with multiple administrations involved, and overlapping uses of space with commercial fishing, aquaculture, navigation and tourism, among others. The lack of strong and representative fishing associations hampers research and management initiatives. Effective communication between recreational fishers, researchers and fisheries managers is also lacking. Despite the ecological, social and economic relevance of MRF, there is no systematic and comprehensive collection of information on fishing effort, recreational catches, expenses, social profile and access conditions of European recreational fishers. These data would be useful to avoid biases in the assessment of recreational fisheries due to the great diversity of ecosystems, species and typologies of users. Strategic recommendations and research priorities were also identified to address knowledge gaps and are discussed in the context of the management of MRF across Europe.  相似文献