nature

当前位置: Nature » 进化生态 » 正文

Nature:变暖增强硬水湖的二氧化碳吸收

摘要 : 我们对于气候变化对来自富含碳酸盐的硬水湖的碳通量的潜在影响知之甚少。这项研究报告了过去二十年北美中部这样的湖泊中从二氧化碳源到汇所发生的一个变化以及年平均pH值的升高。

 u=2626238361,756571170&fm=21&gp=0

我们对于气候变化对来自富含碳酸盐的硬水湖的碳通量的潜在影响知之甚少。这项研究报告了过去二十年北美中部这样的湖泊中从二氧化碳源到汇所发生的一个变化以及年平均pH值的升高。所观察到的pH值及二氧化碳吸收量的变化被归因于由大气变暖诱导的春季冰层的减少,这种减少降低了冰下二氧化碳积累、升高了春季和夏季的pH值、并且增强了硬水湖中二氧化碳的化学吸收。

原文链接:

Decrease in CO2 efflux from northern hardwater lakes with increasing atmospheric warming

Boreal lakes are biogeochemical hotspots that alter carbon fluxes by sequestering particulate organic carbon in sediments1, 2 and by oxidizing terrestrial dissolved organic matter to carbon dioxide (CO2) or methane through microbial processes3, 4. At present, such dilute lakes release ~1.4 petagrams of carbon annually to the atmosphere3, 4, and this carbon efflux may increase in the future in response to elevated temperatures5 and increased hydrological delivery of mineralizable dissolved organic matter to lakes6, 7. Much less is known about the potential effects of climate changes on carbon fluxes from carbonate-rich hardwater and saline lakes that account for about 20 per cent of inland water surface area4, 8. Here we show that atmospheric warming may reduce CO2 emissions from hardwater lakes. We analyse decadal records of meteorological variability, CO2 fluxes and water chemistry to investigate the processes affecting variations in pH and carbon exchange9, 10 in hydrologically diverse lakes of central North America. We find that the lakes have shifted progressively from being substantial CO2 sources in the mid-1990s to sequestering CO2 by 2010, with a steady increase in annual mean pH. We attribute the observed changes in pH and CO2 uptake to an atmospheric-warming-induced decline in ice cover in spring that decreases CO2 accumulation under ice, increases spring and summer pH, and enhances the chemical uptake of CO2 in hardwater lakes. Our study suggests that rising temperatures do not invariably increase CO2 emissions from aquatic ecosystems.

对应Nature杂志: 2015年03月12日Nature杂志精选

来源: Nature 浏览次数:57

热门文章TOP

RSS订阅 - 填写您的邮件地址,订阅我们的精彩内容: - 网站地图
网站联系电话:020-87540820 备案号:粤ICP备11050685号-8 增值电信业务经营许可证:粤B2-20120479
©2011-2015 生物帮 All rights reserved.