Bull kelp Nereocystis luetkeana is an important foundation species, providing structural habitat and nutrients to the nearshore ecosystems of temperate coastal regions in the Northeast Pacific. Sensitive to environmental conditions, this species thrives in cool, nutrient‐rich water. Reported declines in the extent and distribution of bull kelp may reflect changing oceanic conditions and result in breakdown of important food chains and ecosystem services. This study uses satellite remote sensing to map kelp bed extent from 2004 to 2017 in the Salish Sea on the West Coast of British Columbia, Canada and examines the relationship between trends in kelp persistence with local and global scale environmental conditions. In our study area, we found limited evidence of kelp decline. Local scale effects of current speed, temperature and substrate type may play a role in the spatial and temporal patterns of persistence. Kelp persistence was higher in sites with rocky substrate and lower in areas with low current and gravel or sand substrate. A decline in kelp was recorded from a high in 2015 to a low in 2017; however, a longer and more complete record is needed to distinguish declining trends from natural variability. This work highlights the importance of continued collection of long‐term data for use in time series of kelp abundance as multiple factors can influence the reliability of image interpretation and kelp classification.

中文翻译：

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使用卫星遥感的加拿大不列颠哥伦比亚省西海岸近岸海带床的时空持久性

公牛海带Nereocystis luetkeana是重要的基础物种，为东北太平洋温带沿海地区的近岸生态系统提供结构性栖息地和养分。对环境条件敏感，该物种在凉爽，营养丰富的水中繁殖。据报告，海带的范围和分布减少可能反映了海洋状况的变化，并导致重要的食物链和生态系统服务崩溃。这项研究使用卫星遥感技术绘制了2004年至2017年加拿大不列颠哥伦比亚省西海岸萨利什海的海藻床分布图，并研究了海藻持久性趋势与本地和全球规模环境条件之间的关系。在我们的研究区域，我们发现海带下降的证据有限。当前速度的局部比例效应，温度和底物类型可能在持久性的时空模式中起作用。在有岩石基质的地方，海带的持久性较高，在低水流和砾石或沙子基质的区域，海带的持久性较低。海带从2015年的高位下降至2017年的低位; 但是，需要更长和更完整的记录来区分下降趋势与自然变异。这项工作强调了继续收集长期数据以用于海带丰度时间序列的重要性，因为多个因素会影响图像解释和海带分类的可靠性。需要更长，更完整的记录来区分下降趋势与自然变异。这项工作强调了继续收集长期数据以用于海带丰度时间序列的重要性，因为多个因素会影响图像解释和海带分类的可靠性。需要更长，更完整的记录来区分下降趋势与自然变异。这项工作强调了继续收集长期数据以用于海带丰度时间序列的重要性，因为多个因素会影响图像解释和海带分类的可靠性。