KMS Chongqing Institute of Green and Intelligent Technology, CAS
| Anthropogenic land use substantially increases riverine CO2 emissions | |
Gu, Shijie1,2,3; Li, Siyue4  ; Santos, Isaac R.5,6
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| 2022-08-01 | |
| 摘要 | Carbon dioxide (CO2) emissions from inland waters to the atmosphere are a pivotal component of the global carbon budget. Anthropogenic land use can influence riverine CO2 emissions, but empirical data exploring cause-effect relationships remain limited. Here, we investigated CO2 partial pressures (pCO(2)) and degassing in a monsoonal river (Yue River) within the Han River draining to the Yangtze in China. Almost 90% of river samples were supersaturated in CO2 with a mean f standard deviation of 1474 +/- 1614 mu atm, leading to emissions of 557 - 971 mmol/m(2)/day from river water to the atmosphere. Annual CO2 emissions were 1.6 - 2.8 times greater than the longitudinal exports of riverine dissolved inorganic and organic carbon. pCO(2) was positively correlated to anthropogenic land use (urban and farmland), and negatively correlated to forest cover. pCO(2) also had significant and positive relationships with total dissolved nitrogen and total dissolved phosphorus. Stepwise multiple regression models were developed to predict pCO(2). Farmland and urban land released nutrients and organic matter to the river system, driving riverine pCO(2) enrichment due to enhanced respiration in these heterotrophic rivers. Overall, we show the crucial role of land use driving riverine pCO(2), which should be considered in future large-scale estimates of CO2 emissions from streams. Land use change can thus modify the carbon balance of urban-river systems by enhancing river emissions, and reforestation helps carbon neutral in rivers. (C) 2022 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. |
| 关键词 | River carbon Inland waters Greenhouse gases Climate change Water quality Headwater streams |
| DOI | 10.1016/j.jes.2021.12.040 |
| 发表期刊 | JOURNAL OF ENVIRONMENTAL SCIENCES
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| ISSN | 1001-0742 |
| 卷号 | 118页码:158-170 |
| 通讯作者 | Li, Siyue(syli2006@163.com) |
| 收录类别 | SCI |
| WOS记录号 | WOS:000773306700016 |
| 语种 | 英语 |
