Radiation dimming and decreasing water clarity fuel underwater darkening in lakes

	Radiation dimming and decreasing water clarity fuel underwater darkening in lakes
	Zhang, Yunlin; Qin, Boqiang; Shi, Kun; Zhang, Yibo; Deng, Jianming; Wild, Martin; Li, Lin; Zhou, Yongqiang; Yao, Xiaolong; Liu, Miao
刊名	SCIENCE BULLETIN
	2020
卷号	65 期号:19 页码:1675-1684
英文摘要	Long-term decreases in the incident total radiation and water clarity might substantially affect the underwater light environment in aquatic ecosystems. However, the underlying mechanism and relative contributions of radiation dimming and decreasing water clarity to the underwater light environment on a national or global scale remains largely unknown. Here, we present a comprehensive dataset of unprecedented scale in China's lakes to address the combined effects of radiation dimming and decreasing water clarity on underwater darkening. Long-term total radiation and sunshine duration showed 5.8% and 7.9% decreases, respectively, after 2000 compared to 1961-1970, resulting in net radiation dimming. An in situ Secchi disk depth (SDD) dataset in 170 lakes showed that the mean SDD significantly decreased from 1.80 +/- 2.19 m before 1995 to 1.28 +/- 1.82 m after 2005. SDD remote sensing estimations for 641 lakes with areas >= 10 km(2) showed that SDD markedly decreased from 1.26 +/- 0.62 m during 1985-1990 to 1.14 +/- 0.66 m during 2005-2010. Radiation dimming and decreasing water clarity jointly caused an approximately 10% decrease in the average available photosynthetically active radiation (PAR) in the euphotic layer. Our results revealed a more important role of decreasing water clarity in underwater darkening than radiation dimming. A meta-analysis of long-term SDD observation data from 61 various waters further elucidated a global extensive underwater darkening. Underwater darkening implies a decrease in water quality for potable water supplies, recession in macrophytes and benthic algae, and decreases in benthic primary production, fishery production, and biodiversity. (C) 2020 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.
内容类型	期刊论文
源URL	[http://159.226.73.51/handle/332005/20216]
专题	中国科学院南京地理与湖泊研究所
推荐引用方式 GB/T 7714	Zhang, Yunlin,Qin, Boqiang,Shi, Kun,et al. Radiation dimming and decreasing water clarity fuel underwater darkening in lakes[J]. SCIENCE BULLETIN,2020,65(19):1675-1684.
APA	Zhang, Yunlin.,Qin, Boqiang.,Shi, Kun.,Zhang, Yibo.,Deng, Jianming.,...&Brookes, Justin D..(2020).Radiation dimming and decreasing water clarity fuel underwater darkening in lakes.SCIENCE BULLETIN,65(19),1675-1684.
MLA	Zhang, Yunlin,et al."Radiation dimming and decreasing water clarity fuel underwater darkening in lakes".SCIENCE BULLETIN 65.19(2020):1675-1684.