Impact of global warming on Antarctic and Arctic seaweeds - consequences for community structure and spatial distribution

南极半岛西部（WAP）和北极地区是全球变暖速度最快的地区。自20世纪50年代以来，WAP的地表水已经变暖了1°C以上，预计下个世纪这两个地区的地表水还会进一步变暖。在极地地区，棕色海藻构建了高度复杂和多产的水下森林，是极地生态系统的重要组成部分。幼藻发育阶段（繁殖体）是藻类生命周期中最敏感的阶段，形成了物种成功生存的瓶颈。在这种情况下，大多数研究都集中在单因素实验上，普遍缺乏测试非生物和生物因素相互作用的实验设计。关于温度、沉积和放牧对极地褐藻繁殖体萌发和补充成功的交互影响，目前尚无资料。因此，我们将在Potter Cove （WAP）、Kongsfjorden （Spitsbergen）和家庭实验室对生态上重要的海藻物种和早期演代群落的繁殖体进行多因子实验，以找出成功繁殖的最重要驱动因素。本研究的目的是将单一物种的多因素实验室实验结果与群落研究和基于多因素gis的栖息地建模结果相结合，以更准确地了解不断变化的环境条件将如何改变极地海藻群落，包括跨学科方法中南极和北极地区的比较。

The Western Antarctic Peninsula (WAP) and the Arctic region are experiencing the fastest rates of global warming worldwide. Surface waters at the WAP have warmed by more than 1 °C since the 1950s and are predicted to warm further into the next century at both regions. In the Polar Regions brown seaweeds build highly complex and productive underwater forests, being an essential part of the polar ecosystem. The young developmental algal stages (propagules) are the most sensitive stage in a life-cycle of an alga, forming the bottle-neck for a successful survival of the species. In this context most studies focussed on single factor experiments, there is a general lack of experimental designs testing the interplay of abiotic and biotic factors. No information on interactive effects of temperature, sedimentation and grazing on the germination and recruitment success of polar brown algal propagules is available to date. Therefore, we will carry out multi-factorial experiments on propagules of ecologically important seaweed species and early successional communities at Potter Cove (WAP), Kongsfjorden (Spitsbergen) and in the home laboratories, in order to indicate the most important drivers for successful reproduction. The aim of this study is to combine the results from the multi-factorial laboratory experiments on single species with results from community research and multifactorial GIS-based habitat modeling to get a more precise picture of how the changing environmental conditions will alter the polar seaweed communities, including comparisons between Antarctic and Arctic regions in an interdisciplinary approach.