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Forestry carbon sink refers to the net income generated by forests, trees and woodlands in the process of absorbing atmospheric carbon dioxide and fixing renewable forest resources. With the rapid development of Chinese economy and accelerating industrialization and urbanization, global climate change has become the focus of attention of all countries. Forest has a strong carbon sink function. The study of forest carbon sequestration and oxygen release value assessment is of great significance for the protection, development and utilization of forest resources and the mitigation of climate change. In this paper, the distributed storage model based on cloud computing architecture was adopted to evaluate the value of forest carbon sequestration and oxygen release. This model can be used to quickly calculate the value of forest carbon sequestration and oxygen release in a certain region, provide data support for forestry carbon sink trading, and provide method reference and scientific basis for forestry carbon sink project accounting. [ABSTRACT FROM AUTHOR]

The Intergovernmental Panel on Climate Change (IPCC) ambitious goal of achieving carbon neutrality by 2050 has been embraced by a variety of countries including South Korea. In South Korea, an increasingly vital neutrality strategy is enhancing carbon absorption through land use planning. A key consideration in these strategies is the comprehensive evaluation of carbon sinks present in various land cover categories. These carbon sinks—most notably forests, grasslands, and wetlands—play a critical role in mitigating the effects of climate change by locking carbon dioxide out of the atmosphere. However, forests and grasslands have long been prime avenues for new exurban development. This study analyzes the effects of large-scale development across several key carbon sinks for the Seoul Metropolitan Area of South Korea. Our findings indicate that the key carbon sinks increased from 2007 to 2021. Regardless, urban development has flourished where greenbelts were released, leading to significant depletion of forests, grasslands, and wetlands. However, converting farmland to New Town developments with massive park systems has contributed to an increase in carbon sinks in some parts of the region. In the perspective of South Korea's goals for carbon neutrality, absorption is insufficient. Therefore, it is necessary to reflect the loss of sinks as a cost of sprawl and frame policies to expand storage through afforestation or reassessment of idle, undeveloped land. • A considerable amount of carbon sinks was lost from developing New Towns on greenbelt lands. • Converting farmland to New Towns with large park systems contributed may increase carbon sinks. • Preserving existing natural carbon sinks and creating large urban park systems in new developments could promote sustainable development and climate mitigation. [ABSTRACT FROM AUTHOR]

Trees absorb CO 2 and reduce the impact of GHGs. This paper deals about the carbon uptake dynamics produced by the management of unused lands as tool to help the fulfilment of international commitments on atmospheric CO 2. The paper introduces a new perspective of using the unused lands around Municipalities to compensate the carbon emissions of urban contexts, according to the Sustainable Energy Action Plans as answer to climate change, already approved by the most part of Cities in Europe. The model of the carbon dynamics is based on a genetic algorithm which allows to find the sequence of operations on the unused land in space (portions of the land) and time (rotation of cuts and plantations) to ensure the reaching of a given outcome in terms of carbon captured. The algorithm, therefore, behaves as design support of land management, enriching the literature available for the sector. The paper identifies two possible original scenarios of storing carbon referred as " emergency " and " constant rate "; the first produces after fifty years a maximum carbon uptake of the order of 100 tC/ha while the second a maximum uptake rate of the order of 2 tC/(year ha), after an initial start-up period of 40–50 years. • Mathematical model to evaluate tree growth and carbon sink from reforestation. • Optimization model to manage the carbon uptake in different scenarios. • Forest represents an effective way to remove carbon from atmosphere. • Carbon stock per unit of unused areas around cities and urban area. • Climate mitigation tool suitable by municipality in the context of SECAPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • CO 2 fluxes were measured in three subtropical mangroves for 16 site years. • VPD stress inhibits mangrove productivity during both exposed and inundated periods. • Meteorological factors and VPD have interactive effects on mangrove productivity. • Tides have independent effects on mangrove productivity through salinity changes. • The threshold effect range of VPD stress on mangrove productivity is 2.50–2.95 kPa. Subtropical mangroves have great potential to sequester atmospheric carbon dioxide (CO 2) and thus significantly contribute to climate change mitigation. Meanwhile, the carbon cycling processes in subtropical mangroves are vulnerable to the changing climatic conditions, such as the warming-induced vapor pressure deficit (VPD) increases. However, the impacts of VPD on net ecosystem production (NEP) in subtropical mangroves remain poorly understood due to a lack of detailed assessment of NEP responses to VPD among different mangrove forests over a long-term observational period. In this study, we deployed eddy-covariance systems to measure net ecosystem CO 2 exchange at three subtropical mangrove forests for 16 site-years, comprising two natural and one artificial forests. We employed a state-of-the-art data-driven modeling approach (i.e., Shapley additive explanations (SHAP) framework based on extreme gradient boosting model), which enabled us to explore the interactive effects of meteorological and tidal factors (e.g. salinity) with VPD on the mangrove NEP. We revealed that air temperature, global solar radiation (GR) and wind speed have significant interactions on the response of NEP to VPD stress in subtropical mangroves. For instance, when GR was high, the SHAP interaction values of VPD and GR on NEP decreased with increasing VPD, but when GR was low, the trends were the opposite. However, instead of identifying interactive effects between tidal salinity and VPD on mangrove NEP, we came across potential independent influence of salinity on the same. SHAP analysis was also able to disentangle the impact of VPD from other abiotic drivers. Thus, we evaluated the threshold effect of VPD stress on NEP loss in subtropical mangroves and observed a range of 2.50–2.95 kPa. Above this range, VPD stress leveled off. The subtropical mangrove responses to VPD should be therefore considered in the dynamic global vegetation models to increase the accuracy in carbon cycle simulations in the future. [ABSTRACT FROM AUTHOR]

Seagrass meadows deliver a range of ecosystem services, where one of the more important is the capacity to store carbon and serve as sinks for atmospheric carbon dioxide. The capacity of seagrass meadows for carbon storage might, however, be modified and complicated by several factors; one important factor is the possible effects of calcification within the meadows. In tropical areas, seagrass meadows can contain high proportions of calcareous organisms, which through their calcification may cause release of CO 2. To study this aspect of the CO 2 balance within tropical seagrass systems, we investigated the air-water CO 2 flux in seagrass mesocosms with different plant community compositions, i.e. mixtures of seagrass and calcifying macroalgae, having similar overall photosynthetic oxygen evolution rates. The measured CO 2 fluxes changed both in rate and direction over the day and were significantly related to plant community composition. Downward fluxes of CO 2 were found only over vegetation with high proportion of seagrass and in the afternoon, whereas occurrence of calcifying algae appeared to reverse the flow. A partial least squares (PLS) regression model indicated that pH, pCO 2 and dissolved inorganic carbon (DIC) were the primary environmental variables predicting the CO 2 fluxes. Our findings show that algal calcification might partly counteract the carbon sequestration in seagrass meadows. • CO 2 fluxes over the surface were significantly related to plant community composition. • Downward fluxes of CO 2 were found only over vegetation with high proportion of seagrass. • pH, pCO 2 and dissolved inorganic carbon (DIC) were the primary environmental variables predicting the CO 2 fluxes. [ABSTRACT FROM AUTHOR]

• Large uncertainties are associated with the future magnitude and stability of the forest carbon sink. • Business-as-usual management practices might already be close-to-optimum for supporting forest carbon uptake and storage. • Increases in management intensity have the potential to lower forest carbon sequestration and stocking capacity. • Forest management practices are as important as climate change to regulatethe carbon sink and stock size. Forest management practices might act as nature-based methods to remove CO 2 from the atmosphere and slow anthropogenic climate change and thus support an EU forest-based climate change mitigation strategy. However, the extent to which diversified management actions could lead to quantitatively important changes in carbon sequestration and stocking capacity at the tree level remains to be thoroughly assessed. To that end, we used a state-of-the-science bio-geochemically based forest growth model to simulate effects of multiple forest management scenarios on net primary productivity (NPP) and potential carbon woody stocks (pCWS) under twenty scenarios of climate change in a suite of observed and virtual forest stands in temperate and boreal European forests. Previous modelling experiments indicated that the capacity of forests to assimilate and store atmospheric CO 2 in woody biomass is already being attained under business-as-usual forest management practices across a range of climate change scenarios. Nevertheless, we find that on the long-term, with increasing atmospheric CO 2 concentration and warming, managed forests show both higher productivity capacity and a larger potential pool size of stored carbon than unmanaged forests as long as thinning and tree harvesting are of moderate intensity. [Display omitted] [ABSTRACT FROM AUTHOR]