Coral vanadium can record tropical cyclones and anthropogenic activities in the South China Sea

Recently, post-industrial environmental concerns have spawned a new field of research focused on the vanadium circulation between air, water, and sediments. Vanadium is widely recognized as a trace pollutant in fossil fuels, especially crude oil, due to its high concentration of vanadium, which can be released into seawater through atmospheric deposition associated with oil spills and combustion.

Furthermore, marine vanadium is a valuable proxy for environmental reconstruction in natural systems due to its abundance and residence time in seawater, its occurrence in several oxidation states that control solubility, and its role in biological metabolism. There is a possibility.

Anthropogenic effects on the global vanadium cycle have similar effects on the global cycles of other anthropogenically mobilized metals, such as lead and mercury, which have received less attention. In particular, research on the geochemistry of vanadium in the ocean, which is a major sink of vanadium mobilized on land, lags far behind other metals.

Coral reefs in tropical seas Corals can provide a valuable environmental archive of trace metals in coastal waters, along with associated natural and anthropogenic factors, and vanadium in corals can provide historical evidence for vanadium in surface waters of coral reefs. It has been successfully and widely applied as a powerful tool for recording changes. .

The research team, led by Professor Kefu Yu (Faculty of Marine Science, Guangxi University), analyzed geochemical proxy data (vanadium/calcium (V/Ca), d¹⁸Oh, d¹³C, etc.) Coral (LW4) vanadium data from Hainan Island, together with coral (W3) skeletons with monthly resolution of 1984 CE around Weizhou Island, South China Sea explaining chronology of vanadium in surface waters in the north.

This study documents for the first time a close relationship between sea surface winds and temporal patterns of V/Ca ratios, suggesting great potential for documenting prehistoric changes in tropical cyclones. This study provided strong evidence for a relationship between vanadium remobilization in marine sediments and ocean redox conditions associated with vertical mixing by surface winds.

However, the differences in each interval under human influence indicate that the sources and drivers of vanadium in surface seawater are too complex to use the coral V/Ca relationship with surface winds as a simple quantitative ratio. I’m here. Furthermore, in this study, it was believed that coral V/Ca ratios could be a potential proxy for surface winds after removal of anthropogenic disturbances.

Encouraged by the chronological consistency between oil spills and coral skeleton V/Ca peaks, this study has recovered historical changes in industrial development and revolution associated with anthropogenic vanadium emissions in the northern South China Sea.

In the early stages (1984 to 1993 CE), relatively high and unstable coral V/Ca ratios were associated with industrial and agricultural activities on the surrounding continent, e.g. was doing.

In the middle stage (1994 to 2008 CE), the low V/Ca ratios in corals were attributed to effective environmental initiatives after the publication of the National Environmental Protection Act. In the last phase (2009 to 2015 CE), the coral V/Ca ratio increased due to the development of the local shipping industry and several extreme peaks associated with oil spills occurred.

This study contributed to the identification of potential new direct geochemical proxies for tropical cyclones and anthropogenic activity that can be reconstructed from data-enabled high-resolution coral skeleton archives in coastal regions. This paper science china earth science.