排序方式: 共有23条查询结果,搜索用时 78 毫秒
21.
Sofia Ribeiro Mikael K. Sejr Audrey Limoges Maija Heikkilä Thorbjørn Joest Andersen Petra Tallberg Kaarina Weckström Katrine Husum Matthias Forwick Tage Dalsgaard Guillaume Massé Marit-Solveig Seidenkrantz Søren Rysgaard 《Ambio》2017,46(1):106-118
In order to establish a baseline for proxy-based reconstructions for the Young Sound–Tyrolerfjord system (Northeast Greenland), we analysed the spatial distribution of primary production and sea ice proxies in surface sediments from the fjord, against monitoring data from the Greenland Ecosystem Monitoring Programme. Clear spatial gradients in organic carbon and biogenic silica contents reflected marine influence, nutrient availability and river-induced turbidity, in good agreement with in situ measurements. The sea ice proxy IP25 was detected at all sites but at low concentrations, indicating that IP25 records from fjords need to be carefully considered and not directly compared to marine settings. The sea ice-associated biomarker HBI III revealed an open-water signature, with highest concentrations near the mid-July ice edge. This proxy evaluation is an important step towards reliable palaeoenvironmental reconstructions that will, ultimately, contribute to better predictions for this High Arctic ecosystem in a warming climate. 相似文献
22.
Lene Hansen Egon Noe Katrine Højring 《Journal of Agricultural and Environmental Ethics》2006,19(2):147-168
The relationship between agriculture and nature is a central issue in the current agricultural debate. Organic Farming has
ambitions and a special potential in relation to nature. Consideration for nature is part of the guiding principals of organic
farming and many organic farmers are committed to protecting natural qualities. However, the issue of nature, landscape, and
land use is not straightforward. Nature is an ambiguous concept that involves multiple interests and actors reaching far beyond
farmers. The Danish research project Nature Quality in Organic Farming has investigated the relationship between nature and organic farming. This article will focus on an expert workshop held
in connection with the project that investigates the way different actors conceptualize nature. Farmers, scientists, and non-governmental
organizations came together to discuss their experiences of nature and expectations of organic agriculture. From this interaction,
it was clear that nature is a contested notion. Different understandings of nature exist within the three groups and there
is disagreement as to whether emphasis should be given to biological qualities, production values, or experiential and aesthetic
perspectives. This complexity provides a challenge to organic farming as well as to the implementation of nature considerations
in general. It illustrates an underlying battle for the right to define nature and nature quality and essentially decide what
organic farmers should work towards. We argue that successful implementation requires organic farmers to carefully consider
what expectations they wish to meet. Optimally it is dependent on a dialog between stakeholder interest groups that allows
for multivocality and pluralism. 相似文献
23.
Pil Uthaug Rasmussen Katrine Uhrbrand Mette Damkj r Bartels Helle Neustrup Dorina Gabriela Karottki Ute B ltmann Anne Mette Madsen 《Frontiers of Environmental Science & Engineering》2021,15(3):41