气候变化背景下湖泊有机碳组分对温度和降水格局改变的响应OA北大核心CHSSCDCSTPCD

Lake wetlands are a huge carbon sink system for mitigating global warming,and there is a highly responsive process of their carbon sink function with the alteration patterns of temperature and precipitation in the context of climate change.In this study,based on 557 observations published in 135 papers,we used meta-analysis to analyse the effects of climate and geographic factor interactions on the organic carbon fractions of lakes on global scale,including Sediment Organic Carbon(SOC),Total Organic Carbon(TOC),Dissolved Organic Carbon(DOC),and Particulate Organic Carbon(POC)in lake water.The results showed that:1)The ranges of SOC,TOC,POC and DOC over the latitude and altitude range of 3°49'N-76°24'N,0-4500 m were 0.25-15.6 g C/Kg,1.9-25.11 mg C/L,0.026-24 mg C/L,1-115.4 mg C/L;(2)Among the geographical factors,the altitude was negative correlation with TOC(P＜0.05),and for every 1 m increase,TOC increased by 0.0077 mg/L;The latitude was negative correlation with POC and positive correlation with DOC(P＜0.05),and for every 1° increase,POC decreased by 0.136 mg/L,DOC increased by 1.18 mg/L;(3)Among the climatic factors,the annual mean temperature was positive correlation with SOC and POC,with DOC was positive correlation(P＜0.05),for every 1° increase,the SOC and POC increased by 0.079 g/kg and 0.36 mg/L,DOC decreased by 1.52 mg/L;Annual mean precipitation was positive correlation with POC and negative correlation with DOC(P＜0.05),and for every 100 mm increase,POC increased by 0.87 mg/L and DOC decreased by 3 mg/L;(4)The contributions of climatic and geographic factors to the combined effects of SOC,TOC,POC,and DOC reached 16.1％,14％,90％,and 61.6％;(5)Precipitation in the hottest season had a positive correlation with SOC,and all climatic parameters had no significant effect on TOC and SOC in lake water;The precipitation factor in the coldest season was the main driver of POC changes,precipitation in the wettest month and wettest season,average temperature in the coldest season were positively correlated with POC;and precipitation in the driest month,the driest area,the hottest season and the coldest season had the most significant effect on DOC.