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1.
Callaghan TV Tweedie CE Akerman J Andrews C Bergstedt J Butler MG Christensen TR Cooley D Dahlberg U Danby RK Daniëls FJ de Molenaar JG Dick J Mortensen CE Ebert-May D Emanuelsson U Eriksson H Hedenås H Henry H R G Hik DS Hobbie JE Jantze EJ Jaspers C Johansson C Johansson M Johnson DR Johnstone JF Jonasson C Kennedy C Kenney AJ Keuper F Koh S Krebs CJ Lantuit H Lara MJ Lin D Lougheed VL Madsen J Matveyeva N Mcewen DC Myers-Smith IH Narozhniy YK Olsson H Pohjola VA Price LW Rigét F Rundqvist S 《Ambio》2011,40(6):705-716
Understanding the responses of tundra systems to global change has global implications. Most tundra regions lack sustained environmental monitoring and one of the only ways to document multi-decadal change is to resample historic research sites. The International Polar Year (IPY) provided a unique opportunity for such research through the Back to the Future (BTF) project (IPY project #512). This article synthesizes the results from 13 papers within this Ambio Special Issue. Abiotic changes include glacial recession in the Altai Mountains, Russia; increased snow depth and hardness, permafrost warming, and increased growing season length in sub-arctic Sweden; drying of ponds in Greenland; increased nutrient availability in Alaskan tundra ponds, and warming at most locations studied. Biotic changes ranged from relatively minor plant community change at two sites in Greenland to moderate change in the Yukon, and to dramatic increases in shrub and tree density on Herschel Island, and in subarctic Sweden. The population of geese tripled at one site in northeast Greenland where biomass in non-grazed plots doubled. A model parameterized using results from a BTF study forecasts substantial declines in all snowbeds and increases in shrub tundra on Niwot Ridge, Colorado over the next century. In general, results support and provide improved capacities for validating experimental manipulation, remote sensing, and modeling studies. 相似文献
2.
Uwayemi M. Sofowote Hayley Hung Ankit K. Rastogi John N. Westgate Yushan Su Ed Sverko Ivy D’Sa Pat Roach Phil Fellin Brian E. McCarry 《Atmospheric environment (Oxford, England : 1994)》2010,44(38):4919-4926
Polycyclic aromatic hydrocarbons (PAH) were measured in air samples at a remote air monitoring site established in the Yukon Territory, Canada as part of a global project (International Polar Year; IPY) to study the potential for atmospheric long-range transport of anthropogenic pollutants to the Arctic. Gas- and particle-phase PAH were collected in polyurethane foam plugs and on glass fibre filters respectively from August 2007 to October 2009. PAH concentrations were found to be highest in the winter months and lowest in summer. The gas/particle partitioning coefficients of 3–5 ringed PAH were computed and seasonal averages were compared. In the summer time, lower molecular mass PAH exhibited relatively higher partitioning into the particle-phase. This particle-phase partitioning led to the shallowest slopes being recorded during summer for the log–log correlation plots between the PAH partition coefficients and their sub-cooled vapour pressures. Air mass back trajectories suggest that local impacts may be more important during the summer time which is marked by increased camping activities at camping sites in the proximity of the sampling station. In conclusion, both summer and wintertime variations in PAH concentrations and gas/particle partitioning are considered to be source- and phototransformation-dependent rather than dependent on temperature-driven shifts in equilibrium partitioning. 相似文献
3.
This study was conducted in the Swedish sub-Arctic, near Abisko, in order to assess the direction and scale of possible vegetation
changes in the alpine–birch forest ecotone. We have re-surveyed shrub, tree and vegetation data at 549 plots grouped into
61 clusters. The plots were originally surveyed in 1997 and re-surveyed in 2010. Our study is unique for the area as we have
quantitatively estimated a 19% increase in tree biomass mainly within the existing birch forest. We also found significant
increases in the cover of two vegetation types—“birch forest-heath with mosses” and “meadow with low herbs”, while the cover
of snowbed vegetation decreased significantly. The vegetation changes might be caused by climate, herbivory and past human
impact but irrespective of the causes, the observed transition of the vegetation will have substantial effects on the mountain
ecosystems. 相似文献
4.
Economic Development,Rural livelihoods,and Ecological Restoration: Evidence from China 总被引:3,自引:0,他引:3
This article uses a case study in Southeast China to demonstrate how the substantial changes in rural livelihoods have been
driven by a combination of “pull” forces from external economic development, and “push” forces from local areas, leading to
a shift in rural household economic activities: household outmigration and de-population of the countryside, changes in energy
consumption, and most importantly, changes in land uses and eventually, ecological restoration. Such dramatic changes are
becoming common across the Chinese countryside. It is pointed out that economic development has generally caused a deterioration
of the environment at least at the early period of economic growth, but the positive impacts, especially in some ecosystem
in rural areas, have become more apparent. 相似文献
5.
Stefano Raccanelli Vladimiro Bonamin Pietro Tundo 《Environmental science and pollution research international》2000,7(3):125-129
Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the “Serenissima
Repubblica”, as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities
based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry
land has avoided association between the concern connected with the pollution derived from these industrial activities and
the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a
level requiring immediate “in depth” studies and interventions, has been fully realized for decades. 相似文献
6.
The arctic tundra ponds at the International Biological Program (IBP) site in Barrow, AK, were studied extensively in the
1970s; however, very little aquatic research has been conducted there for over three decades. Due to the rapid climate changes
already occurring in northern Alaska, identifying any changes in the ponds’ structure and function over the past 30–40 years
can help identify any potential climate-related impacts. Current research on the IBP ponds has revealed significant changes
in the physical, chemical, and biological characteristics of these ponds over time. These changes include increased water
temperatures, increased water column nutrient concentrations, the presence of at least one new chironomid species, and increased
macrophyte cover. However, we have also observed significant annual variation in many measured variables and caution that
this variation must be taken into account when attempting to make statements about longer-term change. The Barrow IBP tundra
ponds represent one of the very few locations in the Arctic where long-term data are available on freshwater ecosystem structure
and function. Continued monitoring and protection of these invaluable sites is required to help understand the implications
of climate change on freshwater ecosystems in the Arctic. 相似文献
7.
The basic idea of LCA is that all environmental burdens connected with a product or service have to be assessed, back to the
raw materials and down to waste removal. Therefore, the term “Life Cycle Assessment” is more precise than the German “?kobilanz”
or the French “écobilan”. This basic idea is undoubtedly true, and LCA is the only environmental assessment tool which avoids
positive ratings for measurements which only consists in the shifting of burdens.
In the years from 1990 to 1993, SETAC and SETAC-Europe shaped the development of LCA in a series of important workshops culminating
in the “Code of Practice” of 1993. The results of these workshops can be illustrated by the famous SETAC-triangle. It shows
the basic structure which is now underlying the standardizing activities of ISO: 1. Goal definition and scoping, 2. Inventory
analysis, 3. Impact assessment, 4. Improvement assessment.
The structure recently defined by ISO differs from the SETAC structure only in the last element which is called “Interpretation”
in the international standard 14040. According to ISO, “Improvement Assessment” is only one of the many activities which may
follow LCA but is not part of the true analysis.
The components of an LCA are described and interpreted in detail, SETAC vs. ISO. Recent developments and activities initiated
by ISO, SPOLD and other organisations complete the review. 相似文献
8.
It seems inevitable that the ongoing and rapid changes in the physical environment of the marine Arctic will push components
of the region’s existing social-ecological systems—small and large—beyond tipping points and into new regimes. Ongoing changes
include warming, freshening, acidification, and alterations to food web structure. In anticipation we pose three distinct
but interrelated challenges: (1) to explore existing connectivities within components of the marine system; (2) to seek indicators
(if they exist) of approaching regime change through observation and modeling; and (3) to build functional resilience into
existing systems through adaptation-oriented policy and to have in hand transformative options when tipping points are crossed
and new development trajectories are required. Each of the above challenges is scale dependent, and each requires a much deeper
understanding than we currently have of connectivity within existing systems and their response to external forcing. Here,
we argue from a global perspective the need to understand the Arctic’s role in an increasingly nonlinear world; then describe
emerging evidence from new observations on the connectivity of processes and system components from the Canada Basin and subarctic
seas surrounding northern North America; and finally posit an approach founded in “resilience thinking” to allow northern
residents living in small coastal communities to participate in the observation, adaption and—if necessary—transformation
of the social-ecological system with which they live. 相似文献
9.
S.J. Oltmans A.S. Lefohn J.M. Harris D.W. Tarasick A.M. Thompson H. Wernli B.J. Johnson P.C. Novelli S.A. Montzka J.D. Ray L.C. Patrick C. Sweeney A. Jefferson T. Dann J. Davies M. Shapiro B.N. Holben 《Atmospheric environment (Oxford, England : 1994)》2010,44(35):4497-4509
During April 2008, as part of the International Polar Year (IPY), a number of ground-based and aircraft campaigns were carried out in the North American Arctic region (e.g., ARCTAS, ARCPAC). The widespread presence during this period of biomass burning effluent, both gaseous and particulate, has been reported. Unusually high ozone readings for this time of year were recorded at surface ozone monitoring sites from northern Alaska to northern California. At Barrow, Alaska, the northernmost point in the United States, the highest April ozone readings recorded at the surface (hourly average values >55 ppbv) in 37 years of observation were measured on April 19, 2008. At Denali National Park in central Alaska, an hourly average of 79 ppbv was recorded during an 8-h period in which the average was over 75 ppbv, exceeding the ozone ambient air quality standard threshold value in the U.S. Elevated ozone (>60 ppbv) persisted almost continuously from April 19–23 at the monitoring site during this event. At a coastal site in northern California (Trinidad Head), hourly ozone readings were >50 ppbv almost continuously for a 35-h period from April 18–20. At several sites in northern California, located to the east of Trinidad Head, numerous occurrences of ozone readings exceeding 60 ppbv were recorded during April 2008. Ozone profiles from an extensive series of balloon soundings showed lower tropospheric features at ~1–6 km with enhanced ozone during the times of elevated ozone amounts at surface sites in western Canada and the U.S. Based on extensive trajectory calculations, biomass burning in regions of southern Russia was identified as the likely source of the observed ozone enhancements. Ancillary measurements of atmospheric constituents and optical properties (aerosol optical thickness) supported the presence of a burning plume at several locations. At two coastal sites (Trinidad Head and Vancouver Island), profiles of a large suite of gases were measured from airborne flask samples taken during probable encounters with burning plumes. These profiles aided in characterizing the vertical thickness of the plumes, as well as confirming that the plumes reaching the west coast of North America were associated with biomass burning events. 相似文献
10.
Tilapia, a tropical freshwater fish native to Africa, is an increasingly important global food commodity. The World Wide Fund
for Nature (WWF), a major environmental nongovernmental organization, has established stakeholder dialogues to formulate farm
certification standards that promote “responsible” culture practices. As a preface to its “tilapia aquaculture dialogue,”
the WWF for Nature commissioned a review of potential certification issues, later published as a peer-reviewed article. This
article contends that both the review and the draft certification standards subsequently developed fail to adequately integrate
critical factors governing the relative sustainability of tilapia production and thereby miss more significant issues related
to resource-use efficiency and the appropriation of ecosystem space and services. This raises a distinct possibility that
subsequent certification will promote intensive systems of tilapia production that are far less ecologically benign than existing
widely practiced semi-intensive alternatives. Given the likely future significance of this emergent standard, it is contended
that a more holistic approach to certification is essential. 相似文献
11.
Paul A. Smith Laura McKinnon Hans Meltofte Richard B. Lanctot Anthony D. Fox James O. Leafloor Mikhail Soloviev Alastair Franke Knud Falk Mikhail Golovatin Vasiliy Sokolov Aleksandr Sokolov Adam C. Smith 《Ambio》2020,49(3):732-748
Tundra-breeding birds face diverse conservation challenges, from accelerated rates of Arctic climate change to threats associated with highly migratory life histories. Here we summarise the status and trends of Arctic terrestrial birds (88 species, 228 subspecies or distinct flyway populations) across guilds/regions, derived from published sources, raw data or, in rare cases, expert opinion. We report long-term trends in vital rates (survival, reproduction) for the handful of species and regions for which these are available. Over half of all circumpolar Arctic wader taxa are declining (51% of 91 taxa with known trends) and almost half of all waterfowl are increasing (49% of 61 taxa); these opposing trends have fostered a shift in community composition in some locations. Declines were least prevalent in the African-Eurasian Flyway (29%), but similarly prevalent in the remaining three global flyways (44–54%). Widespread, and in some cases accelerating, declines underscore the urgent conservation needs faced by many Arctic terrestrial bird species. 相似文献
12.
Matthieu Guillemain Johan Elmberg Michel Gauthier-Clerc Grégoire Massez Richard Hearn Jocelyn Champagnon Géraldine Simon 《Ambio》2010,39(2):170-180
Animal populations are exposed to large-scale anthropogenic impact from e.g. climate change, habitat alteration and supplemental
stocking. All of these may affect body condition in wintering dabbling ducks, which in turn may affect an individual’s survival
and reproductive success. The aim of this study was to assess whether there have been morphometric changes in Mallard (Anas platyrhynchos) and Teal (Anas crecca) over the last 30 years at a major wintering site. Body mass and condition increased from the 1950s–1960s to the 2000s in
both species. The increase in body mass amounted to as much as 11.7%, with no corresponding change in body size. Improved
body condition was maintained from early to mid-winter, but then converged with historical values for late winter. Our interpretation
is that increasingly benign ambient winter conditions permit ducks to maintain better energetic “safety margins” throughout
winter, and that converging spring departure values may be related to evolutionary flight energetic optima. The observed changes
are consistent with large-scale climate amelioration and local/regional habitat improvement (both anthropogenic). 相似文献
13.
Bioaccumulation Factors (BAFs) and Biota to Sediment Accumulation Factors (BSAFs) for PCBs in pike and eels 总被引:1,自引:0,他引:1
Stuart J. Harrad David J. T. Smith 《Environmental science and pollution research international》1997,4(4):189-193
“Freely-dissolved” aqueous concentrations of 9 trichlorothrough heptachlorobiphenyls are reported, alongside those in sediments
and fish from the R. Severn. For most congeners, BSAFs and lipid-normalised BAFs for pike exceed those for eels. Whilst R.
Severn BSAFs are comparable with those for L. Ontario trout and New Bedford Harbour flounder, R. Severn BAFs are 1–2 orders
of magnitude lower. This discrepancy may be due to inter-species variability, as well as inter-laboratory differences between
operational definitions of “freely-dissolved” aqueous PCB, underlining that the same operational definition must be employed
if R. Severn BAFs are extrapolated elsewhere. For eels, correlation of Log Kow with Log BAF is better (R2 = 0.66) than with BSAF (R2 = 0.13), whilst similar correlation coefficients (R2 = 0.81 and 0.82) were observed for pike. When Log Kow is plotted against BSAF and Log BAF for both species combined, better correlation is observed for Log BAF (R2 = 0.65), than BSAF (R2 = 0.36). For both species combined, the observed relationship between Log BAF and Log Kow for trichloro-through heptachlorobiphenyls is: Log BAF = 0.96 * Log Kow −0.24. 相似文献
14.
Michel Mench Jean-Paul Schwitzguébel Peter Schroeder Valérie Bert Stanislaw Gawronski Satish Gupta 《Environmental science and pollution research international》2009,16(7):876-900
Purpose
The term “phytotechnologies” refers to the application of science and engineering to provide solutions involving plants, including phytoremediation options using plants and associated microbes to remediate environmental compartments contaminated by trace elements (TE) and organic xenobiotics (OX). An extended knowledge of the uptake, translocation, storage, and detoxification mechanisms in plants, of the interactions with microorganisms, and of the use of “omic” technologies (functional genomics, proteomics, and metabolomics), combined with genetic analysis and plant improvement, is essential to understand the fate of contaminants in plants and food, nonfood and technical crops. The integration of physicochemical and biological understanding allows the optimization of these properties of plants, making phytotechnologies more economically and socially attractive, decreasing the level and transfer of contaminants along the food chain and augmenting the content of essential minerals in food crops. This review will disseminate experience gained between 2004 and 2009 by three working groups of COST Action 859 on the uptake, detoxification, and sequestration of pollutants by plants and consequences for food safety. Gaps between scientific approaches and lack of understanding are examined to suggest further research and to clarify the current state-of-the-art for potential end-users of such green options. 相似文献15.
We summarize the latest results on the rapid changes that are occurring to Arctic sea ice thickness and extent, the reasons
for them, and the methods being used to monitor the changing ice thickness. Arctic sea ice extent had been shrinking at a
relatively modest rate of 3–4% per decade (annually averaged) but after 1996 this speeded up to 10% per decade and in summer
2007 there was a massive collapse of ice extent to a new record minimum of only 4.1 million km2. Thickness has been falling at a more rapid rate (43% in the 25 years from the early 1970s to late 1990s) with a specially
rapid loss of mass from pressure ridges. The summer 2007 event may have arisen from an interaction between the long-term retreat
and more rapid thinning rates. We review thickness monitoring techniques that show the greatest promise on different spatial
and temporal scales, and for different purposes. We show results from some recent work from submarines, and speculate that
the trends towards retreat and thinning will inevitably lead to an eventual loss of all ice in summer, which can be described
as a ‘tipping point’ in that the former situation, of an Arctic covered with mainly multi-year ice, cannot be retrieved. 相似文献
16.
Ben-Shlomo R Shanas U 《Environmental science and pollution research international》2011,18(8):1264-1269
Purpose
We tested the genetic diversity in wild mice (Mus musculus domesticus) inhabiting the asbestos-polluted area as a model for the long-term mutagenic effect of asbestos. Hazardous effects of deposited asbestos persist in the environment because of low rate of fiber disintegration. The upper layers of the soil in the vicinity of a former asbestos factory are nearly “saturated” with asbestos fibers and dust. Natural populations of mice dwell in this area and are constantly exposed to asbestos fibers. 相似文献17.
Building on achievements and experience gained through the EU project DAMOCLES and international data management during the International Polar Year, ACCESS, data management was implemented using the same platform as used for DAMOCLES. A metadata-driven approach through which all datasets are properly described with discovery and use metadata was chosen in order to simplify data management and data usage. The system provides automated submission and checking of datasets, search and download as well as visualisation and transformation on user demand and metadata export. Long-term management of ACCESS climate datasets is done within the context of the Arctic Data Centre. This ensures visibility of ACCESS datasets in the context of WMO and GEOSS catalogues. Challenges with ACCESS data management have mainly been cultural with the consequence that the system has been underutilised within the duration of the project duration. 相似文献
18.
Stefan Gartiser Christoph Hafner Christoph Hercher Kerstin Kronenberger-Schäfer Albrecht Paschke 《Environmental science and pollution research international》2010,17(4):856-865
Background, aim and scope
The applicability of the Whole Effluent Assessment concept for the proof of compliance with the “best available techniques” has been analysed with paper mill wastewater from Germany by considering its persistency (P), potentially bio-accumulative substances (B) and toxicity (T). 相似文献19.
Karl-Heinz Schwind Jamshid Hosseinpour Heidelore Fiedler Christoph Lau Otto Hutzinger 《Umweltwissenschaften und Schadstoff-Forschung》1994,6(5):243-246
Im Rahmen eines Untersuchungsprogrammes zur Schadstoffemission von Paraffin-, Stearin- und Bienenwachskerzen ohne Farb- und
Lackbeimischungen wurden sowohl die Wachse und Dochte als auch die Brandgase dieser Kerzen auf die toxikologisch besonders
relevanten Schadstoffklassen der PCDD/PCDF, PAK und kurzkettigen Aldehyde untersucht. Die toxikologische Bewertung kommt selbst
bei einem angenommenen „worst case“-Szenario und unter Berücksichtigung von geltenden Grenz- und Richtwerten zu dem Ergebnis,
da? von den untersuchten Kerzen kein zus?tzliches Gesundheitsrisiko ausgeht.
Exhaust fumes of paraffin, beeswax and stearin candles without any further paint or decorative element were analysed for the
toxicological important substance classes of PCDD/PCDF, PAH and short chain aldehydes. The candle waxes and wicks were investigated
for chlorinated dioxins, furans and some known precursors. Toxicological risk assessment shows that emissions of the investigated
candles are much lower than all administrative limitation values — even under “worst case conditions”. Thus, they do not produce
a toxicological risk for human health. 相似文献
20.
Krämer W 《Environmental science and pollution research international》2012,19(4):1332-1334
The recent claim made in this journal that nuclear bomb tests and the Chernobyl disaster caused distortions in the secondary
sex ratio is shown to be a likely artifact of data mining, misused statistics, and misreading of the evidence. In particular,
the concept of statistical “significance” and its limitations do not seem to be fully understood, and important confounding
factors have not been accounted for. 相似文献