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There have been assessments of the carbon (C) offsetting potential of China's forest sector using historical inventories and future projections. Here, we critically reflect on the assessments we have done and carefully synthesize our findings of China's C sequestration by forest ecosystems and storage by harvested wood products (HWPs). We show that China raised its forest stock volume by 5.069 × 109 m3 during 2006–2020, giving a biomass C uptake of 2.592 petagrams (Pg). With a cumulative C emission of 37.031 Pg during the same period of time, the offsetting ratio of forest biomass is 6.99%. If C stored in HWPs during the period (0.491 Pg) is included, that ratio rises to 8.33%; further counting C sequestered by forest soil (1.277 Pg) boosts the ratio to 11.76%. With a stock volume increase of 14.813 × 109 m3 from 2006 to 2060, projected under a conventional scenario, the forest sector C removal could reach 9.286 Pg without including soil C or 13.017 Pg otherwise, offsetting 10.50% or 14.72% of the cumulative emission of 88.425 Pg. These results indicate that the forest sector has played and will continue to play a significant a role in its decarbonizing drive, but the government has been conservative in setting its targets, particularly for the increase of forest stock volume. Future policy and research efforts must effectively link the country's forest structure, quality, and growth, and thus C sequestration and storage, with improved forest management and wood products manufacturing. [ABSTRACT FROM AUTHOR]

The northern margin of the North China Craton (NNCC) hosts Mesozoic gold deposits of significant economic importance. The metal sources of these gold systems have long been debated with mainly magmatic‐hydrothermal versus metamorphic fluid models. Mercury (Hg) isotopes, which undergo unique mass‐independent fractionation, can provide important insights into the source of metals in gold deposits due to the close association between Hg and Au in such systems. Here, we investigated the Hg isotopic composition of six gold deposits of the Middle Jurassic to Early Cretaceous age and potential source rocks in the NNCC. Variable ∆199Hg values were observed in bulk ore and pyrite samples (−0.28‰ to 0.34‰, n = 51) and coeval granites (−0.21‰ to 0.13‰; n = 25). The negative ∆199Hg values of bulk ore and pyrite samples mostly agree with that observed for metamorphic basement rocks (−0.37‰ to 0.11‰; n = 32). The positive ∆199Hg values of bulk ore and pyrite samples agree with those reported in marine sediments (0‰–0.3‰). So the data suggest binary mixing of ocean‐recycled Hg originated from the subducted oceanic slab, and terrestrial‐recycled Hg from the Precambrian basement in Mesozoic gold deposits. The contribution of Hg (and Au, by analogy) from both reservoirs varies depending on active continental arc versus intracontinental setting and is ultimately controlled by translithospheric heat flow driven by paleo‐Pacific plate subduction. Plain Language Summary: Photoreduction of Hg(II) on Earth's surface system leads to mass‐independent fractionation of Hg isotopes, resulting in positive and negative Δ199Hg values in marine and terrestrial systems, respectively. Here, we observe negative to positive Δ199Hg values in the Mesozoic gold deposits in the northern margin of the North China Craton. These results suggest binary mixing of ocean‐recycled Hg from the fluids released by subducting oceanic slab or the mantle metasomatized by these fluids, and terrestrial‐recycled Hg from the Precambrian basement in Mesozoic gold deposits. Paleo‐Pacific plate subduction and translithospheric heat flow may have played a key role in the metallogenic metal enrichment of the Mesozoic gold deposits in the northern margin of the North China Craton. Key Points: Mass‐independent fraction of Hg isotopes is observed in Mesozoic gold deposits in the northern margin of the North China CratonPositive Δ199Hg values in Mesozoic gold deposits suggest Hg was sourced from lithospheric mantle modified by oceanic subductionNegative Δ199Hg values in Mesozoic gold deposits suggest that Hg was sourced from the Precambrian basement [ABSTRACT FROM AUTHOR]