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1.
A comprehensive reconstruction of the Baltic Sea state from 1850 to 2006 is presented: driving forces are reconstructed and the evolution of the hydrography and biogeochemical cycles is simulated using the model BALTSEM. Driven by high resolution atmospheric forcing fields (HiResAFF), BALTSEM reproduces dynamics of salinity, temperature, and maximum ice extent. Nutrient loads have been increasing with a noteworthy acceleration from the 1950s until peak values around 1980 followed by a decrease continuing up to present. BALTSEM shows a delayed response to the massive load increase with most eutrophic conditions occurring only at the end of the simulation. This is accompanied by an intensification of the pelagic cycling driven by a shift from spring to summer primary production. The simulation indicates that no improvement in water quality of the Baltic Sea compared to its present state can be expected from the decrease in nutrient loads in recent decades.  相似文献   

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3.
Intraguild predation interactions make fish communities prone to exhibit alternative stable states with either piscivore or prey fish dominance. In the Baltic Sea, local declines of coastal piscivores like perch (Perca fluviatilis) have been observed to coincide with high densities of sticklebacks (Gasterosteus aculeatus). Mechanisms behind this shift between piscivore and stickleback dominance were studied both experimentally and in field. Results showed that predation by sticklebacks has a strong negative effect on perch larvae survival, but this effect rapidly decreases with increasing perch size, likely due to gape limitations and digestion constraints in sticklebacks. Large spatial and temporal variations in patterns of stickleback migration into perch spawning sites were observed. Whether or not high density of sticklebacks will cause declines in coastal piscivore populations is suggested to depend on the availability of spawning sites in which sticklebacks do not migrate into or arrive late in the reproduction season of coastal piscivores.  相似文献   

4.
Nutrient loads from inland sources to the Baltic Sea and adjacent inland waters need to be reduced in order to prevent eutrophication and meet requirements of the European Water Framework Directive (WFD) and the Baltic Sea Action Plan (BSAP). We here investigate the spatial implications of using different possible criteria for reducing water-borne phosphorous (P) loads in the Northern Baltic Sea River Basin District (NBS-RBD) in Sweden. Results show that most catchments that have a high degree of internal eutrophication do not express high export of P from their outlets. Furthermore, due to lake retention, lake catchments with high P-loads per agricultural area (which is potentially of concern for the WFD) did not considerably contribute to the P-loading of the Baltic Sea. Spatially uniform water quality goals may, therefore, not be effective in NBS-RBD, emphasizing more generally the need for regional adaptation of WFD and BSAP-related goals.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0523-x) contains supplementary material, which is available to authorized users.  相似文献   

5.
The interactions of cetyltrimethylammonium (CTA) with mitochondria have been investigated. We confirm, as already observed in a previous paper, that this compound behaves as proton carrier (or uncoupler) of the oxidative phosphorylation, but evidences suggest that this compound enhances the membrane permeability to many other compounds such as sucrose. We conclude therefore that CTA as a detergent enhances membrane permeability to all ions including protons. Some evidences are also given that the inhibitory effect of CTA on the mitochondrial respiratory chain is a consequence of the swelling induced.  相似文献   

6.
Havenhand JN 《Ambio》2012,41(6):637-644
Increasing partial pressure of atmospheric CO2 is causing ocean pH to fall—a process known as ‘ocean acidification’. Scenario modeling suggests that ocean acidification in the Baltic Sea may cause a ≤3 times increase in acidity (reduction of 0.2–0.4 pH units) by the year 2100. The responses of most Baltic Sea organisms to ocean acidification are poorly understood. Available data suggest that most species and ecologically important groups in the Baltic Sea food web (phytoplankton, zooplankton, macrozoobenthos, cod and sprat) will be robust to the expected changes in pH. These conclusions come from (mostly) single-species and single-factor studies. Determining the emergent effects of ocean acidification on the ecosystem from such studies is problematic, yet very few studies have used multiple stressors and/or multiple trophic levels. There is an urgent need for more data from Baltic Sea populations, particularly from environmentally diverse regions and from controlled mesocosm experiments. In the absence of such information it is difficult to envision the likely effects of future ocean acidification on Baltic Sea species and ecosystems.  相似文献   

7.
Past, present, and possible future changes in the Baltic Sea acid–base and oxygen balances were studied using different numerical experiments and a catchment–sea model system in several scenarios including business as usual, medium scenario, and the Baltic Sea Action Plan. New CO2 partial pressure data provided guidance for improving the marine biogeochemical model. Continuous CO2 and nutrient measurements with high temporal resolution helped disentangle the biogeochemical processes. These data and modeling indicate that traditional understandings of the nutrient availability–organic matter production relationship do not necessarily apply to the Baltic Sea. Modeling indicates that increased nutrient loads will not inhibit future Baltic Sea acidification; instead, increased mineralization and biological production will amplify the seasonal surface pH cycle. The direction and magnitude of future pH changes are mainly controlled by atmospheric CO2 concentration. Apart from decreasing pH, we project a decreasing calcium carbonate saturation state and increasing hypoxic area.  相似文献   

8.
This paper examines the relation between the results of epidemiologic studies of air pollution mortality and impact indicators that can be informative for environmental policy decisions. Using models that are simple and transparent, yet contain the essential features, it is shown that (1) number of deaths is not meaningful for air pollution, whereas loss of life expectancy (LLE) is an appropriate impact indicator; (2) the usual short-term (time series) studies yield a change in daily number of deaths attributable to acute effects of pollution, without any information on the associated LLE (although some information on this has recently become available by extending the observation window of time series); and (3) long-term studies yield a change in age-specific mortality, which makes it possible to calculate the total population averaged LLE (acute and chronic effects) but not the total number of premature deaths attributable to air pollution. The latter is unobservable because one cannot distinguish whether few individuals suffer a large or many suffer a small LLE. The paper calculates the LLE from exposure to PM10, as implied by the long-term mortality studies of adults and infants; population LLE for infants turns out to be an order of magnitude smaller than for adults. The LLE implied by short-term studies is a small fraction of the total loss implied by long-term studies, even if one assumes a very high loss per death. Applied to environmental policy, taking a permanent 50-70% reduction of PM10 as a reasonable goal, one finds a corresponding increase of average life expectancy in urban areas of the European Union (EU) and the United States of approximately four months.  相似文献   

9.
《Environmental Forensics》2013,14(3):161-165
The distribution of aromatic contaminants between environmental solids and water solution reflects both absorption by the organic matrix (organic carbon, OC) and adsorption to black carbon (BC). In many instances, adsorption to BC dominates the interaction between aromatic contaminants and environmental solids. This holds especially true for the pyrogenically produced PAHs and PCDD/Fs, but also for the industrially produced PCBs and PCNs. In the future, research will need to surface-normalize the adsorption onto BC surfaces. One of the key questions to be addressed is the relative distribution and availability of contaminants associated with OC and BC fractions in environmental solids.  相似文献   

10.
Hormetic lifespan extension is, for obvious reasons, beneficial to an individual. But is this effect really cost-neutral? To answer this question, four tannic polyphenols were tested on the nematode Caenorhabditis elegans. All were able to extend the lifespan, but only some in a hormetic fashion. Additional life trait variables including stress resistance, reproductive behavior, growth, and physical fitness were observed during the exposure to the most life extending concentrations. These traits represent the quality of life and the population fitness, being the most important parameters of a hormetic treatment besides lifespan. Indeed, it emerged that each life-extension is accompanied by a constraining effect in at least one other endpoint, for example growth, mobility, stress resistance, or reproduction. Thus, in this context, longevity could not be considered to be attained for free and therefore it is likely that other hormetic benefits may also incur cost-intensive and unpredictable side-effects.  相似文献   

11.
Environmental Science and Pollution Research - This study investigates the dynamic linkage among foreign direct investment, energy consumption, and environmental pollution of China spanning from...  相似文献   

12.
Mercury (Hg) is a toxic element that is emitted to the atmosphere through human activities, mainly fossil fuel combustion. Hg accumulations in soil are associated with atmospheric deposition, while coal-burning power plants remain the most important source of anthropogenic mercury emissions. In this study, we analyzed the Hg concentration in the topsoil of the Kozani–Ptolemais basin where four coal-fired power plants (4,065 MW) run to provide 50 % of electricity in Greece. The study aimed to investigate the extent of soil contamination by Hg using geostatistical techniques to evaluate the presumed Hg enrichment around the four power plants. Hg variability in agricultural soils was evaluated using 276 soil samples from 92 locations covering an area of 1,000 km2. We were surprised to find a low Hg content in soil (range 1–59 μg kg?1) and 50 % of samples with a concentration lower than 6 μg kg?1. The influence of mercury emissions from the four coal-fired power plants on soil was poor or virtually nil. We associate this effect with low Hg contents in the coal (1.5–24.5 μg kg?1) used in the combustion of these power plants (one of the most Hg-poor in the world). Despite anthropic activity in the area, we conclude that Hg content in the agricultural soils of the Kozani–Ptolemais basin is present in low concentrations.  相似文献   

13.
Environmental Science and Pollution Research - Nanotechnology is a novel arena with promising applications in the field of medicine, industry, and agriculture including fisheries....  相似文献   

14.
This paper examines the history of air pollution control in the State of New Jersey, particularly, how it relates to the development of the state-local governmental relationship, and to the coordination of their respective control efforts. It also describes the methodology for developing local control programs. The information presented in the paper is directed to those individuals who may be able to analogize the experience in New Jersey to situations developing in their own jurisdictions.  相似文献   

15.
Many epidemiologic studies have observed, in different contexts, a slight short-term relationship between particles in air and cardiopulmonary mortality, even when air quality standards were respected. The causality of this relationship is important to public health because of the number of people exposed. Our aim was to make a critical assessment of the arguments used in 15 reviews of published studies. We explain the importance of distinguishing validity from causality, and we systematically analyze the various criteria of judgment within the context of ecologic time studies. Our conclusion is that the observed relationship is valid and that most of the causality criteria are respected. It is hoped that the level of exposure of populations to these particles be reduced. In Europe, acting at the root of the problem, in particular on diesel emissions, will also enable the reduction of levels of other pollutants that can have an impact on health. In the United States, the situation is more complicated, as particles are mainly secondary. It is also essential to continue with research to become better acquainted with the determinants of personal global exposures and to better understand the toxic role of the various physicochemical factors of the particles.  相似文献   

16.
Abstract

Greenhouses are enclosed structures which have various characteristics that enhance crop productivity, but the implications for workers’ pesticide exposure and uptake are not well understood. A narrative literature review was conducted to explore the mechanism/s of interactions between greenhouse characteristics and occupational pesticide exposure. Using a “work”, “worker” and “workplace” conceptual framework, the greenhouse environment (hot and humid microclimate, limited space and dense crop arrangements) combines with work characteristics (high work and pesticide use intensity, multi-tasking, predominantly manual spraying techniques and quick reentry to treated farms) to potentially increase occupational pesticide exposure, compared with open field farming. Greenhouse environments, are variable but have been shown to influence pesticide availability, route, pathways and frequency of exposure, deposition and distribution on a worker’s body as well as use and performance of exposure control methods. Training programs can emphasize the differences in exposure potential between greenhouse and open field farming. Development of tailored guidelines for exposure control strategies to better suit the level of uniqueness of greenhouse agriculture seems warranted.  相似文献   

17.
Carlsson L  Lazdinis M 《Ambio》2004,33(6):366-370
After the break-up of the Soviet system, the divergence in forest management among Soviet republics became obvious. While the forest sectors of the Baltic States have been fundamentally changed, Russia has not been able to develop an institutional framework that would fit the prerequisites for social-ecological resilience. It is argued that sustainable development requires institutional frameworks that have the capacity to adapt and learn, and thus to treat policies as experiments that are constantly assessed and readjusted. This, however, requires a participatory approach and in this respect the Baltic States are believed to be on a more promising track. Finally, it is concluded that only to the extent that suitable institutional frameworks will be developed will social-ecological resilience be a significant feature of the natural resources management in the former communist countries.  相似文献   

18.
The Anthropocene: are humans now overwhelming the great forces of Nature?   总被引:4,自引:0,他引:4  
Steffen W  Crutzen J  McNeill JR 《Ambio》2007,36(8):614-621
We explore the development of the Anthropocene, the current epoch in which humans and our societies have become a global geophysical force. The Anthropocene began around 1800 with the onset of industrialization, the central feature of which was the enormous expansion in the use of fossil fuels. We use atmospheric carbon dioxide concentration as a single, simple indicator to track the progression of the Anthropocene. From a preindustrial value of 270-275 ppm, atmospheric carbon dioxide had risen to about 310 ppm by 1950. Since then the human enterprise has experienced a remarkable explosion, the Great Acceleration, with significant consequences for Earth System functioning. Atmospheric CO2 concentration has risen from 310 to 380 ppm since 1950, with about half of the total rise since the preindustrial era occurring in just the last 30 years. The Great Acceleration is reaching criticality. Whatever unfolds, the next few decades will surely be a tipping point in the evolution of the Anthropocene.  相似文献   

19.
Environmental Science and Pollution Research - Although some regulatory agencies have claimed that consumer exposures to tetrabromobisphenol A (TBBPA) are not likely to cause adverse health effects...  相似文献   

20.
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