Net CO2 and CH4 emissions from restored mangrove wetland: New insights based on a case study in estuary of the Pearl River, China.

Mangroves have the potential to affect climate via C sequestration and methane (CH4) emissions. With half of the world's mangroves lost during the 20th century, mangrove restoration in mitigating greenhouse gases has been increasingly recognized. However, the carbon exchanges during restored processes still remain large uncertain. In this study, we analyzed the temporal variations of CO2 and CH4 fluxes and their environmental controls during 2019 and 2020 based on a closed-path eddy covariance (EC) system in a 12-year restored subtropical mangrove wetland, in estuary of the Pearl River, southeastern China. We also estimated the CO2 and CH4 fluxes and their climate effect from the beginning of restoration by Random Forest algorithm (RF). The EC observations showed that annually the 12-year restored mangrove acted as CO2 and CH4 sources, with net CO2 ecosystem exchange (NEE) of 82-175 gC·m- 2·a-1 and CH4 fluxes of 24.7-26.3 gC·m-2·a-1. Low vegetation gross primary productivity (GPP) and high ecosystem respiration (Re) caused net CO2 emissions in the mangroves. The estimation by RF indicated that the mangroves were always a CO2 source after the beginning of restoration, but the annual NEE was linearly decreased from 233 to 131 gC·m-2·a-1 from 2008 to 2020. The annual CH4 emissions continually increased from 19.0 to 25.8 gC·m-2·a-1 after restoration. As a result, the restored mangrove had a positive effect on climate warming, with increased GWP from 1276 to 1386 g CO2-eq ·m-2·a-1 from 2008 to 2020. This is mainly due to lower GPP and higher Re by young restored mangroves, large water area as well as low salinity induced strong CH4 emissions. Our results indicate new sights that young restored mangrove with large area of water surface may act as carbon sources. However, the long-term climate and ecosystem benefits due to mangrove restoration should not be ignored in future.

New threats to health data privacy.

BACKGROUND: Along with the rapid digitalization of health data (e.g. Electronic Health Records), there is an increasing concern on maintaining data privacy while garnering the benefits, especially when the data are required to be published for secondary use. Most of the current research on protecting health data privacy is centered around data de-identification and data anonymization, which removes the identifiable information from the published health data to prevent an adversary from reasoning about the privacy of the patients. However, published health data is not the only source that the adversaries can count on: with a large amount of information that people voluntarily share on the Web, sophisticated attacks that join disparate information pieces from multiple sources against health data privacy become practical. Limited efforts have been devoted to studying these attacks yet. RESULTS: We study how patient privacy could be compromised with the help of today's information technologies. In particular, we show that private healthcare information could be collected by aggregating and associating disparate pieces of information from multiple online data sources including online social networks, public records and search engine results. We demonstrate a real-world case study to show user identity and privacy are highly vulnerable to the attribution, inference and aggregation attacks. We also show that people are highly identifiable to adversaries even with inaccurate information pieces about the target, with real data analysis. CONCLUSION: We claim that too much information has been made available electronic and available online that people are very vulnerable without effective privacy protection.