Biogeochemical and physical properties influencing the nutrient reservoirs of subsurface water in the changing Canada Basin  

作　　者：Tianzhen Zhang Qiang Hao Haiyan Jin Youcheng Bai Yanpei Zhuang Jianfang Chen 

机构地区：[1]Key Laboratory of Marine Ecosystem Dynamics,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China [2]Ocean College,Zhejiang University,Zhoushan 316021,China [3]Polar and Marine Research Institute,Jimei University,Xiamen 361021,China

出　　处：《Acta Oceanologica Sinica》2024年第10期40-47,共8页海洋学报（英文版）

基　　金：The National Natural Science Foundation of China under contract No.41941013;the National Key R&D Program of China under contract No.2019YFE0120900.

摘　　要：The Canada Basin is the largest basin in the Arctic Ocean.Its unique physical features have the highest concentration of nutrients being found in the subsurface layer,referred to as the subsurface nutrient maximum layer(SNM).Under climate change in the Arctic,the SNM is an essential material base for primary productivity.However,long-term trends of nutrient variations and dominant factors related to nutrient levels in the SNM are still unclear.In this study,we analyzed the SNM variations and main influencing factors of the Canada Basin based on the Global Ocean Data Analysis Project Version 2 between 1990 and 2015 and the Chinese Arctic Research Expedition between 2010 and 2016.We found that the nutrient concentrations in the SNM were relatively stable for decades[average concentrations of nitrate,phosphate,and silicate were(13.6±2.4)μmol/L,(1.8±0.2)μmol/L,and(31.5±5.7)μmol/L,respectively].Nutrient reservoirs were dominated by physical processes.Inflow and outflow water of the SNM contributed about 60.4%and-50.2%to the nutrient stocks,respectively,while particle deposition and remineralization in the Canada Basin contributed approximately one-third to the nutrient stocks.Nitrogen fixation and denitrification in the Canada Basin had no substantial impact on nutrient stocks.The overall stabilization of the SNM over the past few decades implied that the SNM would not substantially affect short term primary productivity.Understanding the long-term trends and dominant factors of reservoirs in the SNM will provide useful insights into the changing Canada Basin ecosystem.

关 键 词：subsurface nutrients maximum layer Canada Basin biogeochemical cycles Arctic climate changes 

分 类 号：P593[天文地球—地球化学] P734[天文地球—地质学]