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2018
2018
2018
Impacts of the autumn Arctic sea ice on the intraseasonal reversal of the winter Siberian high
Science Press
2018
2018
2018
A portion of Colombia’s water resources is located on the Pacific coast within the territory of the Community Council of Alto and Medio Dagua (CC-AMDA). Though a harmonious balance between the communities’ subsistent activities and nature was maintained for centuries, the appearance of modern modes of resource extraction has negatively affected the environment, especially the water resources. The Driver-Pressure-State- Impact-Response (DPSIR) framework was used to analyze water quality problems within this community council. The DPSIR analysis revealed that agriculture, mining, logging and infrastructure development constitute important sectoral drivers with some contribution from tourism and fisheries. Pressures included inputs of organic matter, sediment, nutrients and chemical contaminants to the Dagua river, and to the Bay of Buenaventura. These produced corresponding State changes in the water bodies. Impacts on human welfare were poor public health, reduced food and water security, economic loss and some displacement. Societal Responses included public protests and campaigns, legal actions and policy changes for improved governance. As a future policy option, the formation of community-based water resources management is recommended. Though DPSIR was able to link cause-effect relations, further empirical research on these water bodies is necessary to fill in existing gaps in the data set, particularly for public health threatening contaminants.
Taylor & Francis
2018
2018
2018
2018
Monitoring of environmental contaminants in air and precipitation. Annual report 2017.
This monitoring report presents data from 2017 and time-trends for the Norwegian programme for Long-range atmospheric transported contaminants. The results cover 180 organic compounds and 11 heavy metals. The organic contaminants include regulated persistent organic pollutants (POPs) as
well as POP-like contaminants not yet subjected to international regulations. Five groups of new POP-like contaminants were included for the first time in 2017.
NILU
2018
Environmental Contaminants in an Urban Fjord, 2017
This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analyses
of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of
blood and eggs from herring gull and eider duck. The programme also included inputs of pollutants
via surface water (storm water), and effluent water and sludge from a sewage treatment plant. The
bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The
exposure to/accumulation of the contaminants was also assessed in birds. A vast number of chemical
parameters have been quantified, in addition to some biological effect parameters in cod, and the
report serves as valuable documentation of the concentrations of these chemicals in different
compartments of the Inner Oslofjord marine ecosystem.
Norsk institutt for vannforskning
2018
Extreme winter events that damage vegetation are considered an important climatic cause of arctic browning—a reversal of the greening trend of the region—and possibly reduce the carbon uptake of northern ecosystems. Confirmation of a reduction in CO2 uptake due to winter damage, however, remains elusive due to a lack of flux measurements from affected ecosystems. In this study, we report eddy covariance fluxes of CO2 from a peatland in northern Norway and show that vegetation CO2 uptake was delayed and reduced in the summer of 2014 following an extreme winter event earlier that year. Strong frost in the absence of a protective snow cover—its combined intensity unprecedented in the local climate record—caused severe dieback of the dwarf shrub species Calluna vulgaris and Empetrum nigrum. Similar vegetation damage was reported at the time along ~1000 km of coastal Norway, showing the widespread impact of this event. Our results indicate that gross primary production (GPP) exhibited a delayed response to temperature following snowmelt. From snowmelt up to the peak of summer, this reduced carbon uptake by 14 (0–24) g C m−2 (~12% of GPP in that period)—similar to the effect of interannual variations in summer weather. Concurrently, remotely-sensed NDVI dropped to the lowest level in more than a decade. However, bulk photosynthesis was eventually stimulated by the warm and sunny summer, raising total GPP. Species other than the vulnerable shrubs were probably resilient to the extreme winter event. The warm summer also increased ecosystem respiration, which limited net carbon uptake. This study shows that damage from a single extreme winter event can have an ecosystem-wide impact on CO2 uptake, and highlights the importance of including winter-induced shrub damage in terrestrial ecosystem models to accurately predict trends in vegetation productivity and carbon sequestration in the Arctic and sub-Arctic.
2018