Estimates of upwelling rates in the Arabian Sea and the equatorial Indian Ocean based on bomb radiocarbon

Radiocarbon measurements were made in the water column of the Arabian Sea and the equatorial Indian Ocean during 1994, 1995 and 1997 to assess the temporal variations in bomb 14C distribution and its inventory in the region with respect to GEOSECS measurements made during 1977-1978. Four GEOSECS stations were reoccupied (three in the Arabian Sea and one in the equatorial Indian Ocean) during this study, with all of them showing increased penetration of bomb 14C along with decrease in its surface water activity. The upwelling rates derived by model simulation of bomb 14C depth profile using the calculated exchange rates ranged from 3 to 9 m a(-1). The western region of the Arabian Sea experiencing high wind-induced upwelling has higher estimated upwelling rates. However, lower upwelling rates obtained for the stations occupied during this study could be due to reduced 14C gradient compared to that during GEOSECS.     

Decision-making on process risk of Arctic route for LNG carrier via dynamic Bayesian network modeling

An increasing number of ships have chosen the suitable route to transport in Arctic waters during summer. Seeking a suitable model for risk decision-making in route planning is a necessary research topic at present. Due to its complex natural environment, there is significant uncertainty regarding ship navigation safety in Arctic waters. The process risk-based decision-making method to support route planning is established based on the dynamic Bayesian network (DBN) risk assessment model for LNG carrier collision with ice or obstacles in Arctic waters. The decision-making process for ship navigation is dynamically associated with time. Therefore, a Markov Chain (MC) is built for each dynamic node in Bayesian belief network (BBN) to realize DBN associated risk assessment, which is called process risk and is applied to decision-making. Three possible routes for ships sailing from the Vikitsky Strait to the Long Strait in Arctic waters were selected in conjunction with the objective daily change data of wind speed, temperature, wave height, and ice condition. Simulations for risk decision-making in the ship navigation process are performed. Application examples show that the ship selected either ROUTE2 (Vikitsky Strait – Laptev Sea – Sannikov Strait – Eastern Siberian Sea – Long Strait) or ROUTE3 (Vikitsky Strait – Laptev Sea – Proliv Dmitriya Lapteva – Eastern Siberian Sea – Long Strait) in August as the best navigable route.     

Is alloparenting helpful for Mednyi Island arctic foxes, Alopex lagopus semenovi?

The Arctic Fox Alopex lagopus semenovi population on Mednyi Island is completely isolated and subsists largely by scavenging on seabird colonies, which have remained abundant and spatio-temporally predictable for many years. We compared population data at the beginning of 1976/1978 and some time after 1994–2005, finding an 85% decline in fox numbers due to disease, to assess the effect of population size on social structure. A total of 81 groups of known size and composition was observed during this 29-year period. Overall, helpers (usually non-lactating yearling females) occurred in 25.7% of groups, and in 32.4% of groups there were two or three lactating females. Female engagement in alloparental behaviour decreased, but not statistically significantly, after the decline in population density. Total food availability was apparently constant throughout the study period, and therefore, the amount available per individual was much higher later in the study. Both communally nursing females and helpers brought food and helped to guard the litter. However, the benefits of communal rearing were unclear. While cubs were left without guards significantly more rarely in the groups with an additional adult, the number of cubs weaned per lactating female was greater in groups with one (3.93 ± 1.60), as opposed to two or three (3.06 ± 0.92), lactating females. Survival of cubs to 1 year of age in the groups with two lactating females and/or with helpers was lower than that in the families with one lactating female without helpers (22.2% vs 32.2%). Fewer second-generation litters were born to foxes produced by composite families than to those produced by pairs. Reproductive adults producing by pairs had, on average, 1.23 (±1.72) second-generation litters. In groups that initially included additional adults, the average number of second-generation litters per reproductive female was 0.21 (±0.49) and 0.46 (±0.81) litters per male. Thus, according to three measures, increased group size had no apparent positive impact on reproductive success. The increased parental investment and enhanced guarding of the cubs in the larger families could be beneficial under conditions of high population density and a saturated biotope to which the island fox population was presumably adapted before the population crash in the late 1970s.     

基于HSI 模型的印度洋大眼金枪鱼栖息地研究

根据日本商业性金枪鱼延绳钓生产数据,应用栖息地指数模型(HSI)和地理信息系统(GIS)图形显示技术对印度洋大眼金枪鱼的栖息地分布进行研究.研究结果表明:印度洋大眼金枪鱼最适合栖息的海域主要集中在70°E以东,15°S以北印度洋海域,栖息地指数值在0.75～1.00;而20°E～50°E,30°S～40°S海域以及65°E～120°E,20°S～40°S之间大部分海域的大眼金枪鱼HSI指数集中在0.25～0.50之间;其余海域的大眼金枪鱼HSI指数均分布在0.50～0.75之间.     

The Potential of Current- and Wind-Driven Transport for Environmental Management of the Baltic Sea

The ever increasing impact of the marine industry and transport on vulnerable sea areas puts the marine environment under exceptional pressure and calls for inspired methods for mitigating the impact of the related risks. We describe a method for preventive reduction of remote environmental risks caused by the shipping and maritime industry that are transported by surface currents and wind impact to the coasts. This method is based on characterizing systematically the damaging potential of the offshore areas in terms of potential transport to vulnerable regions of an oil spill or other pollution that has occurred in a particular area. The resulting maps of probabilities of pollution to be transported to the nearshore and the time it takes for the pollution to reach the nearshore are used to design environmentally optimized fairways for the Gulf of Finland, Baltic Proper, and south-western Baltic Sea.     

The environmental state at sea

Seas and oceans are confronted with a plethora of environmental problems, caused by land-based activities (agriculture, industries, and ports) and by maritime activities (such as shipping, fishing, oil and gas drilling, tourism, and navigational dredging). Environmental problems at sea challenge the efficacy of state sovereignty. Who is responsible, accountable, and regulates environmental and spatial problems at the level of regional seas, and what is the role of states in these processes of governance? In the regional seas and on the high seas, the environmental state is challenged by two developments: states become players at different levels, and states are confronted with the activities of big market players where they have no or little jurisdiction. The different forms of the environmental state in Europe’s regional seas and in the Arctic Ocean are examined.     

全氟羟基物质在冠海豹(Hooded seals)体内的母源性传递

在野生动物物种中,乳汁在传递全氟烃基物质(PFASs)于后代中所起的作用,人类还了解甚少。本文以雌性冠海豹及其生产的一对幼崽为研究对象,在哺乳期间,对母体血浆和乳汁中的8种PFASs进行了定量检测,以及对乳汁在PFASs传递过程中所起的作用进行了分析。选择冠海豹是因为它的泌乳周期短(3~ 4 d),在此期间幼崽仅以乳汁为食。胎盘或乳汁传递成为幼崽体内PFASs的唯一来源。通过对8种PFASs的分析(Σ8PFAS),发现7种存在于所有样品中;因此,乳汁是幼崽体内PFASs的来源。在所有样本中,全氟辛烷磺酰基化合物是优势PFAS。Σ8PFAS的平均浓度为母体血浆中6.0 ng/g蛋白(36 ng/g湿重),乳汁中0.77 ng/g蛋白(3.2 ng/g湿重)以及幼崽血浆中12 ng/g蛋白(66 ng g湿重)。血浆中检测到的PFASs浓度在已有报道的其他海豹物种体内检测到的浓度范围之内,低于已知的实验啮齿动物的毒性阈值。PFASs从母体到幼崽的传递效率的个体差异,依赖于PFASs碳键长度、相对传递量最低的为中间能级键的PFASs (C9-C10)。结果显示母体通过乳汁和胎盘传递PFASs,其中胎盘传递是主导途径。
精选自Randi Gr?nnestad, Gro D. Villanger, Anuschka Polder, Kit M. Kovacs, Christian Lydersen, Bj?rn M. Jenssen, Katrine Borg?. Maternal transfer of perfluoroalkyl subastances in hooded seals. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 763–770, July 2017. DOI: 10.1002/etc.3623
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3623/full
     

Air concentrations of currently used herbicides and legacy compounds in the Canadian prairies,subarctic, and arctic

Passive air samplers were installed in the summers of 2005 and 2007 for 90 days at four locations in the agricultural region of the Canadian Prairies and at five locations in the Canadian Subarctic and Arctic. The presence and masses of ten currently used herbicides and three legacy compounds in the polyurethane foam disks were quantified. Herbicides 2,4-D, bromoxynil and MCPA were detected at all locations in the Canadian Prairies and in both years because these herbicides are widely applied to control broadleaf weeds in cereal crops that are an integral part of Prairie agricultural production systems. MCPA was also detected at one location in the Arctic in 2007. The detection of the other seven herbicides in the 2 years combined ranged from no detections (atrazine only) to five detections for the relatively volatile herbicides trifluralin and triallate. Triallate was the only other herbicide detected in the Arctic (2005). Legacy compounds were either not detected (alachlor) or at levels near their detection level (γ-HCH and α-HCH). γ-HCH and α-HCH were more frequently detected in 2005 than in 2007 indicating that their concentrations in Canadian air have decreased over time. γ-HCH, widely used as an insecticide in Prairie oilseed production until 2002, was detected at larger concentrations in the Canadian Prairies than in the Subarctic and Arctic. α-HCH, a manufacturing by-product in technical HCH prior to 1971 in Canada, was not detected in the Canadian Prairies but was at detectable levels in the Subarctic and Arctic as the Arctic Ocean is reported to be a major source of α-HCH to the atmosphere. We conclude that some of the most widely used herbicides in Canadian agriculture today are commonly present in the air in regions where they are applied and that a portion of these herbicides may be traveling as parent molecules to the Canadian Arctic. To the authors’ knowledge, this is the first evidence of the presence of MCPA and triallate in Arctic air samples, perhaps because previous research has seldomly monitored for currently used herbicides in this region.     

Mapping Human Dimensions of Climate Change Research in the Canadian Arctic

This study maps current understanding and research trends on the human dimensions of climate change (HDCC) in the eastern and central Canadian Arctic. Developing a systematic literature review methodology, 117 peer reviewed articles are identified and examined using quantitative and qualitative methods. The research highlights the rapid expansion of HDCC studies over the last decade. Early scholarship was dominated by work documenting Inuit observations of climate change, with research employing vulnerability concepts and terminology now common. Adaptation studies which seek to identify and evaluate opportunities to reduce vulnerability to climate change and take advantage of new opportunities remain in their infancy. Over the last 5 years there has been an increase social science-led research, with many studies employing key principles of community-based research. We currently have baseline understanding of climate change impacts, adaptation, and vulnerability in the region, but key gaps are evident. Future research needs to target significant geographic disparities in understanding, consider risks and opportunities posed by climate change outside of the subsistence hunting sector, complement case study research with regional analyses, and focus on identifying and characterizing sustainable and feasible adaptation interventions.     

Using Available Information to Assess the Potential Effects of Climate Change on Vegetation in the High Arctic: North Billjefjorden, Central Spitsbergen (Svalbard)

We review the available data that can be used to assess the potential impact of climate change on vegetation, and we use central Spitsbergen, Svalbard, as a model location for the High Arctic. We used two sources of information: recent and short-term historical records, which enable assessment on scales of particular plant communities and the landscape over a period of decades, and palynological and macrofossil analyses, which enable assessment on time scales of hundreds and thousands of years and on the spatial scale of the landscape. Both of these substitutes for standardized monitoring revealed stability of vegetation, which is probably attributable to the harsh conditions and the distance of the area from sources of diaspores of potential new incomers. The only evident recent vegetation changes related to climate change are associated with succession after glacial retreats. By establishing a network of permanent plots, researchers will be able to monitor immigration of new species from diversity 'hot spots' and from an abandoned settlement nearby. This will greatly enhance our ability to understand the effects of climate change on vegetation in the High Arctic.