Potential drivers and consequences of regional phosphate depletion in the western subtropical North Pacific

作者：Zhongwei Yuan, Thomas J. Browning, Ruifeng Zhang, Chengwang Wang, Chuanjun Du, Yanmin Wang, Ying Chen, Zhiyu Liu, Xin Liu, Dalin Shi, Minhan Dai · 发表于：Limnology and Oceanography Letters · 年份：2023 · DOI：10.1002/lol2.10314 · 被引用次数：20 · 研究领域：Marine and coastal ecosystems、Microbial Community Ecology and Physiology、Marine Biology and Ecology Research

Abstract In regions of the nitrogen limited low latitude ocean, phosphate can also be depleted to levels initiating stress responses in marine microbes. Here, we associate a broad region of phosphate depletion in the subtropical North Pacific with different levels of phosphorus stress. Nutrient and aerosol addition experiments demonstrated primary nitrogen limitation of the bulk phytoplankton community, with supply of aerosols relieving this limitation. At northern sites with depleted phosphate, alkaline phosphatase activities were enhanced, indicating elevated phosphorus stress. Analysis of satellite‐ and model‐derived aerosol loading showed that aerosol deposition was elevated in these regions. Surface rate measurements suggested that the regional enhancement in phosphate depletion was predominantly driven by elevated nitrogen fixation, likely stimulated by the coincident supply of aerosol iron. Such observations are important for predicting future biogeochemical responses in the subtropical North Pacific to changing aerosol supply.