Assessing the impact of climate change on dissolved oxygen using a flow field ecosystem model that takes into account the anaerobic and aerobic environment of bottom sediments  

作　　者：Jinichi Koue 

机构地区：[1]Graduate School of Maritime Sciences,Kobe University,5-1-1 Fukaeminami,Higashinada-ku,Kobe,Hyogo 658-0022,Japan

出　　处：《Acta Geochimica》2025年第1期11-22,共12页地球化学学报(英文)

基　　金：Open Access funding provided by Kobe University;This research was partially performed by the Environment Research and Technology Development Fund(2RL-2301)of the Environmental Restoration and Conservation Agency provided by Ministry of the Environment of Japan.

摘　　要：This study examines the potential impacts o climate change on Lake Biwa,Japan’s largest freshwate lake,with a focus on temperature,wind speed,and pre cipitation variations.Leveraging data from the IPCC Sixth Assessment Report,including CCP scenarios,projecting a significant temperature rise of 3.3–5.7℃in the case o very high GHG emission power,the research investigates how these shifts may influence dissolved oxygen levels in Lake Biwa.Through a one-dimensional model incorporat ing sediment redox reactions,various scenarios where ai temperature and wind speed are changed are simulated.I is revealed that a 5℃increase in air temperature leads to decreasing 1-2 mg/L of dissolved oxygen concentrations from the surface layer to the bottom layer,while a decrease in air temperature tends to elevate 1–3 mg/L of oxygen lev els.Moreover,doubling wind speed enhances surface laye oxygen but diminishes it in deeper layers due to increased mixing.Seasonal variations in wind effects are noted with significant surface layer oxygen increases from 0.4to 0.8 mg/L during summer to autumn,increases from 0.4 to 0.8 mg/L in autumn to winter due to intensified vertica mixing.This phenomenon impacts the lake’s oxygen cycle year-round.In contrast,precipitation changes show limited impact on oxygen levels,suggesting minor influence com pared to other meteorological factors.The study suggests the necessity of comprehensive three-dimensional models that account for lake-specific and geographical factors fo accurate predictions of future water conditions.A holistic approach integrating nutrient levels,water temperature,and river inflow is deemed essential for sustainable management of Lake Biwa’s water resources,particularly in addressing precipitation variations.

关 键 词：Climate change Dissolved oxygen Sediment redox reaction Stratifi cation Water quality 

分 类 号：P343.3[天文地球—水文科学] P467[天文地球—地球物理学]