Addressing global warming,a common change today,requires achieving peak carbon dioxide emissions and carbon neutrality(also referred to as the dual carbon goals).Enhancing research on the carbon cycle is urgently need...Addressing global warming,a common change today,requires achieving peak carbon dioxide emissions and carbon neutrality(also referred to as the dual carbon goals).Enhancing research on the carbon cycle is urgently needed as the foundation.Water,a key carrier in the carbon cycle,necessitates investigation into groundwater carbon pools’contribution to atmospheric carbon sinks.This study assessed carbon stocks in the Yinchuan Basin’s soil and groundwater carbon pools.Findings indicate the basin’s surface soils contain approximately 24.16 Tg of organic carbon and a total of 60.01 Tg of carbon.In contrast,the basin’s groundwater holds around 4.90 Tg of carbon,roughly one-fifth of the organic carbon in surface soils.Thus,groundwater and soil carbon pools possess comparable carbon stocks,underscoring the importance of the groundwater carbon pool.Studies on terrestrial carbon balance should incorporate groundwater carbon pools,which deserve increased focus.Evaluating groundwater carbon pools’contributions is vital for achieving the dual carbon goals.展开更多
The measurement of atmospheric O_(2)concentrations and related oxygen budget have been used to estimate terrestrial and oceanic carbon uptake.However,a discrepancy remains in assessments of O_(2)exchange between ocean...The measurement of atmospheric O_(2)concentrations and related oxygen budget have been used to estimate terrestrial and oceanic carbon uptake.However,a discrepancy remains in assessments of O_(2)exchange between ocean and atmosphere(i.e.air-sea O_(2)flux),which is one of the major contributors to uncertainties in the O_(2)-based estimations of the carbon uptake.Here,we explore the variability of air-sea O_(2)flux with the use of outputs from Coupled Model Intercomparison Project phase 6(CMIP6).The simulated air-sea O_(2)flux exhibits an obvious warming-induced upward trend(~1.49 Tmol yr−2)since the mid-1980s,accompanied by a strong decadal variability dominated by oceanic climate modes.We subsequently revise the O_(2)-based carbon uptakes in response to this changing air-sea O_(2)flux.Our results show that,for the 1990−2000 period,the averaged net ocean and land sinks are 2.10±0.43 and 1.14±0.52 GtC yr−1 respectively,overall consistent with estimates derived by the Global Carbon Project(GCP).An enhanced carbon uptake is found in both land and ocean after year 2000,reflecting the modification of carbon cycle under human activities.Results derived from CMIP5 simulations also investigated in the study allow for comparisons from which we can see the vital importance of oxygen dataset on carbon uptake estimations.展开更多
Limiting human-caused global warming to a specific level requires achieving net-zero anthropogenic carbon dioxide(CO_(2))emissions,along with strong reductions in other greenhouse gas(GHG)emissions.This means that any...Limiting human-caused global warming to a specific level requires achieving net-zero anthropogenic carbon dioxide(CO_(2))emissions,along with strong reductions in other greenhouse gas(GHG)emissions.This means that any remaining anthropogenic CO_(2)emissions must be balanced by an equivalent amount of anthropogenic removals.展开更多
Assessing the carbon sink potential of marine aquaculture is critical to fostering sustainable marine economic development and achieving carbon neutrality.This study evaluates the carbon sink potential of four nearsho...Assessing the carbon sink potential of marine aquaculture is critical to fostering sustainable marine economic development and achieving carbon neutrality.This study evaluates the carbon sink potential of four nearshore aquaculture systems in China:floating raft,net cage,pond,and tidal flat.China’s coastal aquaculture shows a dramatic potential range from−5401.28×10^(4)t to 84.65×10^(4)t,acting as both a carbon sink and a source.Floating raft(11.19×10^(4)t to 105.65×10^(4)t)and tidal flat(42.83×10^(4)t to 114.35×10^(4)t)are net carbon sinks.In contrast,net cage(−427.39×10^(4)t to−4.26×10^(4)t)and pond(−5027.91×10^(4)t to−131.09×10^(4)t)are significant net carbon sources.This heterogeneity is driven by differences in species,feed inputs,energy consumption,and management practices.The results highlight the need for targeted low-carbon technologies in high-emission systems to maximize carbon sequestration and mitigate their environmental impacts.This study provides a scientific basis for optimizing carbon management and offers insights for global sustainable aquaculture and carbon neutrality.展开更多
Global climate change has significantly altered the patterns of Annual Snow Cover(ASC),including glaciers,which in turn,have reshaped regional hydrological processes.These changes profoundly impact the weathering rate...Global climate change has significantly altered the patterns of Annual Snow Cover(ASC),including glaciers,which in turn,have reshaped regional hydrological processes.These changes profoundly impact the weathering rates of continental rocks and their associated carbon sink potential,particularly for silicate(Eq.(1))and carbonate(Eq.(2))rocks under natural conditions[1-3].Low Temperature(Tem)in regions with ASC typically limit the rates of chemical weathering and the occurrence of weathering products.However,as the ASC melts,the chemical weathering processes previously suppressed by ice begin to accelerate progressively[3,4].In regions where ASC diminishes but does not fully expose the ground,increased meltwater alleviates the restrictive effects of solid moisture on regional chemical weathering.展开更多
The karst geological carbon sink,formed through the chemical weathering of carbonate rocks,is an important part of the global terrestrial carbon sink.It has substantial potential and plays a crucial role in the global...The karst geological carbon sink,formed through the chemical weathering of carbonate rocks,is an important part of the global terrestrial carbon sink.It has substantial potential and plays a crucial role in the global carbon cycle and regional carbon neutrality efforts.The fifth(AR5)and sixth(AR6)assessment reports of the Intergovernmental Panel on Climate Change(IPCC)have clearly affirmed the existence of geological carbon sinks associated with the chemical weathering of carbonate rocks,stating that carbon capture and geological storage are key mitigation schemes.However,numerous studies have shown that exogenous acids are widely involved during the chemical weathering of rocks,adding complexity to the carbon sequestration process and its driving mechanisms.This increases the uncertainty in assessing the carbon sequestration potential.Therefore,a key task is to accurately estimate the geological carbon sinks generated by the chemical weathering of carbonate rocks to resolve the problem of the global carbon sink loss,balancing the carbon budget,and achieving carbon neutrality.In this review,we examine assessments of the carbonate rocks chemical weathering carbon sink influenced by exogenous acids,focusing on the principles,frameworks and methodologies of carbon sink estimation.We also highlight recent advancements,key influencing factors,and underlying driving mechanisms.Looking ahead,we highlight key challenges in enhancing the accuracy and precision of carbonate rocks chemical weathering carbon sink assessments under the influence of exogenous acids.Addressing these issues will support more informed policy decisions on pathways to global carbon neutrality.展开更多
Cities play a pivotal role in global decarbonization,acting as a critical driver of carbon emissions.Accurately allocating carbon mitigation responsibility(CMR)is essential for designing effective and equitable climat...Cities play a pivotal role in global decarbonization,acting as a critical driver of carbon emissions.Accurately allocating carbon mitigation responsibility(CMR)is essential for designing effective and equitable climate policies.How cities manage carbon leakage across boundaries through supply chains and implement plan of increasing forest carbon sinks are important components for designing a fair and inclusive CMR.However,the combined impact of trade-related carbon leakage and forest carbon sinks on CMR allocation remains poorly understood.Here,we develop an integrated CMR allocation framework that accounts for both carbon leakage and variation of forest carbon offsets.When applied to the cities within the GuangdongeHong KongeMacao Greater Bay Area in China,it becomes evident that the in-clusion of carbon leakage results in substantial alterations in mitigation quotas.Adjustments are observed to vary between±10%and 50%across these cities from 2005 to 2020,a trend that is anticipated to continue until 2035.The redistribution of outsourced emissions through supply chains alleviates the mitigation burden on producer cities by 20e30%.Additionally,accounting for carbon sinks substantially influences CMR allocation,particularly in forest-rich cities,which may see their carbon budgets increase by up to 10%.Under an enhanced climate policy scenario,the growth rate of total mitigation quotas from 2025 to 2035 is projected to decrease by 40%compared to a business-as-usual trajectory,reducing the burden on major producer cities.Our proposed CMR framework provides a robust basis for incentivizing coordinated mitigation efforts,promoting decarbonization in supply chains and enhancement of urban carbon sink capacities.展开更多
1.Introduction Carbon neutrality have become a consensus for all of humanity[1,2].As of April,2023,132 countries have announced carbon neutrality targets[3].To achieve carbon neutrality,efforts need to be made from mu...1.Introduction Carbon neutrality have become a consensus for all of humanity[1,2].As of April,2023,132 countries have announced carbon neutrality targets[3].To achieve carbon neutrality,efforts need to be made from multiple aspects,including decarbonization of the power sector[4,5],electrification of the end-use sectors[6,7],and greening of other industries[8].Ecological carbon sinks play a unique role in these strategies to offset hard-to-reduce greenhouse gas(GHG)emissions by reabsorbing or storing carbon that has already been emitted.展开更多
Using China's ground observations,e.g.,forest inventory,grassland resource,agricultural statistics,climate,and satellite data,we estimate terrestrial vegetation carbon sinks for China's major biomes between 19...Using China's ground observations,e.g.,forest inventory,grassland resource,agricultural statistics,climate,and satellite data,we estimate terrestrial vegetation carbon sinks for China's major biomes between 1981 and 2000.The main results are in the following:(1)Forest area and forest biomass car-bon(C)stock increased from 116.5×10^(6) ha and 4.3 Pg C(1 Pg C=10^(15) g C)in the early 1980s to 142.8×10^(6) ha and 5.9 Pg C in the early 2000s,respectively.Forest biomass carbon density increased form 36.9 Mg C/ha(1 Mg C=10^(6) g C)to 41.0 Mg C/ha,with an annual carbon sequestration rate of 0.075 Pg C/a.Grassland,shrub,and crop biomass sequestrate carbon at annual rates of 0.007 Pg C/a,0.014―0.024 Pg C/a,and 0.0125―0.0143 Pg C/a,respectively.(2)The total terrestrial vegetation C sink in China is in a range of 0.096―0.106 Pg C/a between 1981 and 2000,accounting for 14.6%―16.1%of carbon dioxide(CO_(2))emitted by China's industry in the same period.In addition,soil carbon sink is estimated at 0.04―0.07 Pg C/a.Accordingly,carbon sequestration by China's terrestrial ecosystems(vegetation and soil)offsets 20.8%―26.8%of its industrial CO_(2) emission for the study period.(3)Considerable uncertainties exist in the present study,especially in the estimation of soil carbon sinks,and need further intensive investigation in the future.展开更多
Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neu...Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ecosystem C monitoring over broad geographic scale to improve terrestrial biosphere models for accurately evaluating terrestrial C budget and its dynamics under various climate change and policy scenarios.展开更多
Forests play a leading role in regional and global carbon (C) cycles. Detailed assessment of the temporal and spatial changes in C sinks/sources of China's forests is critical to the estimation of the national C b...Forests play a leading role in regional and global carbon (C) cycles. Detailed assessment of the temporal and spatial changes in C sinks/sources of China's forests is critical to the estimation of the national C budget and can help to constitute sustainable forest management policies for climate change. In this study, we explored the spatio-temporal changes in forest biomass C stocks in China between 1977 and 2008, using six periods of the national forest inventory data. According to the definition of the forest inventory, China's forest was categorized into three groups: forest stand, economic forest, and bamboo forest. We estimated forest biomass C stocks for each inventory period by using continuous biomass expansion factor (BEF) method for forest stands, and the mean biomass density method for economic and bamboo forests. As a result, China's forests have accumulated biomass C (i.e., biomass C sink) of 1896 Tg (1Tg=1012g) during the study period, with 1710, 108 and 78 Tg C in forest stands, and economic and bamboo forests, respectively. Annual forest biomass C sink was 70.2 Tg Ca-1 , offsetting 7.8% of the contemporary fossil CO2 emissions in the country. The results also showed that planted forests have functioned as a persistent C sink, sequestrating 818 Tg C and accounting for 47.8% of total C sink in forest stands, and that the old-, mid- and young-aged forests have sequestrated 930, 391 and 388 Tg C from 1977 to 2008. Our results suggest that China's forests have a big potential as biomass C sink in the future because of its large area of planted forests with young-aged growth and low C density.展开更多
The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and the...The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and thermal reservoirs.However,they are increasingly vulnerable to warming and greenhouse gas emissions.展开更多
China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on e...China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on evaluating anthropogenic emissions or the natural carbon cycle separately, and few included trade-related(import and export) CO_(2) emissions and its contribution on global warming. Using the Carbon Tracker CT2019 assimilation dataset and China trade emissions from the Global Carbon Project, we found that the change trend of global CO_(2) flux had obvious spatial heterogeneity, which is mainly affected by anthropogenic CO_(2) flux. From 2000 to 2018, carbon emissions from fossil fuels in the world and in China all showed an obvious increasing trend, but the magnitude of the increase tended to slow down.In 2018, the radiative forcing(RF) caused by China's import and export trade was-0.0038 W m^(-2), and the RF caused by natural carbon budget was-0.0027 W m^(-2), offsetting 1.54% and 1.13% of the RF caused by fossil fuels that year, respectively. From 2000 to 2018, the contribution of China's carbon emission from fossil fuels to global RF was 11.32%. Considering China's import and export trade, the contribution of anthropogenic CO_(2) emission to global RF decreased to 9.50%. Furthermore, taking into account the offset of carbon sink from China's terrestrial ecosystems, the net contribution of China to global RF decreased to 7.63%. This study demonstrates that China's terrestrial ecosystem and import and export trade are all mitigating China's impact on global anthropogenic warming, and also confirms that during the research process on climate change, comprehensively considering the carbon budget from anthropogenic and natural carbon budgets is necessary to systematically understand the impacts of regional or national carbon budgets on global warming.展开更多
Carbonate rock outcrops cover 9%-16% of the continental area and are the principal source of the dissolved inorganic carbon （DIC） transferred by rivers to the oceans, a consequence their dissolution. Current estimat...Carbonate rock outcrops cover 9%-16% of the continental area and are the principal source of the dissolved inorganic carbon （DIC） transferred by rivers to the oceans, a consequence their dissolution. Current estimations suggest that the flux falls between 0.1-0.6 PgC/a. Taking the intermediate value （0.3 PgC/a）, it is equal to 18% of current estimates of the terrestrial vegetation net carbon sink and 38% of the soil carbon sink. In China, the carbon flux from carbonate rock dissolution is estimated to be 0.016 PgC/a, which accounts for 21%, 87.5%-150% and 2.3 times of the forest, shrub and grassland net carbon sinks respectively, as well as 23%-40% of the soil carbon sink flux. Carbonate dissolution is sensitive to environmental and climatic changes, the rate being closely correlated with precipitation, temperature, also with soil and vegetation cover. HCO3 in the water is affected by hydrophyte photosynthesis, resulting in part of the HCO~ being converted into DOC and POC, which may enhance the potential of carbon sequestration by carbonate rock dissolution. The possible turnover time of this carbon is roughly equal to that of the sea water cycle （2000a）. The uptake of atmospheric/soil CO2 by carbonate rock dissolution thus plays an important role in the global carbon cycle, being one of the most important sinks. A major research need is to better evaluate the net effect of this sink in comparison to an oceanic source from carbonate mineral precipitation.展开更多
The sinks/sources of carbon in the Yellow Sea(YS) and East China Sea(ECS), which are important continental shelf seas in China, could exert a great influence on coastal ecosystem dynamics and the regional climate chan...The sinks/sources of carbon in the Yellow Sea(YS) and East China Sea(ECS), which are important continental shelf seas in China, could exert a great influence on coastal ecosystem dynamics and the regional climate change process. The CO_2 exchange process across the seawater-air interface, dissolved and particulate carbon in seawater, and carbon burial in sediments were studied to understand the sinks/sources of carbon in the continental shelf seas of China. The YS and the ECS generally have different patterns of seasonal air-sea CO_2 exchange. In the YS, regions west of 124°E can absorb CO_2 from the atmosphere during spring and winter, and release CO_2 to the atmosphere during summer and autumn. The entire YS is considered as a CO_2 source throughout the year with respect to the atmosphere, but there are still uncertainties regarding the exact air-sea CO_2 exchange flux. Surface temperature and phytoplankton production were the key controlling factors of the air-sea CO_2 exchange flux in the offshore region and nearshore region of the YS, respectively. The ECS can absorb CO_2 during spring, summer, and winter and release CO_2 to the atmosphere during autumn. The annual average exchange rate in the ECS was-4.2±3.2 mmol m^(-2) d^(-1) and it served as an obvious sink for atmospheric CO_2 with an air-sea exchange flux of 13.7×10~6 t. The controlling factors of the air-sea CO_2 exchange in the ECS varied significantly seasonally. Storage of dissolved inorganic carbon(DIC) and dissolved organic carbon(DOC) in the YS and the ECS were 425×10~6 t and 1364×10~6 t, and 28.2×10~6 t and 54.1×10~6 t,respectively. Long-term observation showed that the DOC content in the YS had a decreasing trend, indicating that the "practical carbon sink" in the YS was decreasing. The total amount of particulate organic carbon(POC) stored in the YS and ECS was10.6×10~6 t, which was comparable to the air-sea CO_2 flux in these two continental shelf seas. The amounts of carbon sequestered by phytoplankton in the YS and the ECS were 60.42×10~6 t and 153.41×10~6 t, respectively. Artificial breeding of macroalgae could effectively enhance blue carbon sequestration, which could fix 0.36×10~6–0.45×10~6 t of carbon annually. Organic carbon(OC) buried in the sediments of the YS was estimated to be 4.75×10~6 t, and OC of marine origin was 3.03×10~6 t, accounting for5.0% of the TOC fixed by phytoplankton primary production. In the ECS, the corresponding depositional flux of OC in the sediment was estimated to be 7.4×10~6 t yr^(-1), and the marine-origin OC was 5.5×10~6 t, accounting for 5.4% of the phytoplankton primary production. Due to the relatively high average depositional flux of OC in the sediment, the YS and ECS have considerable potential to store a vast amount of "blue carbon."展开更多
The importance of carbonate weathering carbon sinks(CCSs)is almost equal to that of vegetation photosynthesis in the global carbon cycle.However,CCSs have become controversial in formulating carbon neutral policies to...The importance of carbonate weathering carbon sinks(CCSs)is almost equal to that of vegetation photosynthesis in the global carbon cycle.However,CCSs have become controversial in formulating carbon neutral policies to deal with global climate problems in various countries,since the carbonate dissolution is reversible.In order to address these controversies,we reviewed recent advances in understanding CCSs and examined the outstanding controversies surrounding them.We have analyzed the five controversies,revealing the existence of CCSs,quantifying their magnitude,clarifying their spatiotemporal pattern,and documenting how they have increased and how they evolved under the background of global change.By addressing these five controversies,we help to bring clarity to the role of CCSs in the carbon cycle of global terrestrial ecosystems.展开更多
This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking an...This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking and neutrality goals.This research ana-lyzes the spatial characteristics of carbon metabolism from 2000 to 2020 and uses models to identify stable carbon sink areas,positive carbon flow corridors,and carbon sequestration nodes.The goal is to construct a carbon metabolism spatial security pattern(CMSSP)and propose territorial ecological restoration strategies under different development demand scenarios.The results show the following:1)in 2020,the study area’s carbon sink decreased by 8.29×10^(4) t C/yr compared with that in 2010 and by 10.83×10^(4) t C/yr compared with that in 2000.High-carbon sinks were found mainly in mountainous areas,whereas low-carbon sinks are concentrated in urban con-struction land,rural residential areas,and land margins.2)From 2000 to 2020,the spatial security pattern of carbon metabolism tended to be‘high in the middle of the east and west and low in the gulf.’In 2000,2010,and 2020,16 stable carbon sinks were identified.The carbon energy flow density in Guangxi was greater than that in Guangdong and Hainan,with positive carbon flow corridors located primarily in Guangxi and Guangdong.The number of carbon sequestration nodes remained stable at approximately 15,mainly in Guangxi and Hainan.3)Scenario simulations revealed that under the Nature-based mild restoration scenario,the carbon sink rate will reach 611.85×10^(4) t C/yr by 2030 and increase to 612.45×10^(4) t C/yr by 2060,with stable carbon sinks increasing to 18.In the restora-tion scenario based on Anti-globalization,the carbon sink will decrease from 610.24×10^(4) t C/yr in 2030 to 605.19×10^(4) t C/yr in 2060,with the disappearance of some positive carbon flow corridors and stable carbon sinks.Under the Human-based sustainable restoration scenario,the carbon sink area will decrease from 607.00×10^(4) t C/yr in 2030 to 596.39×10^(4) t C/yr in 2060,with carbon sink areas frag-menting and positive carbon flow corridors becoming less dense.4)On the basis of the current and predicted CMSSPs,this study ex-plores spatial ecological restoration strategies for high-carbon storage areas in bay urban agglomerations at four levels:the land control region,urban agglomeration structure system,carbon sink structure and bay structure control region.展开更多
As an important carbon sink resource,urban park green space plays a key role in carbon absorption and storage in the carbon cycle.The existing assessment models provide the basis for evaluating carbon sink potential o...As an important carbon sink resource,urban park green space plays a key role in carbon absorption and storage in the carbon cycle.The existing assessment models provide the basis for evaluating carbon sink potential of urban park green spaces,but it is still necessary to explore a new index system suitable for it.From the perspective of policy environment,relevant cases and policy guidance at home and abroad all support the inclusion of urban park green spaces in carbon sink trading,and the price trend of carbon sink market is good,but it is necessary to balance maintenance costs and benefits.However,technical barriers such as data collection and monitoring still exist,and technological innovation is needed to break through.At the same time,the improvement of social awareness is also crucial,which needs to be achieved through education and publicity and the design of social participation mechanism.In the implementation path,the key steps should be clear in the short term,and the expected results should be displayed.In the long term,the continuous improvement mechanism should be established,and future goals should be set.展开更多
Forests play a critical role in mitigating cli-mate change by sequestering carbon,yet their responses to environmental shifts remain complex and multifaceted.This special issue,“Tree Rings,Forest Carbon Sink,and Clim...Forests play a critical role in mitigating cli-mate change by sequestering carbon,yet their responses to environmental shifts remain complex and multifaceted.This special issue,“Tree Rings,Forest Carbon Sink,and Climate Change,”compiles 41 interdisciplinary studies exploring forest-climate interactions through dendrochro-nological and ecological approaches.It addresses climate reconstruction(e.g.,temperature,precipitation,isotopes)using tree-ring proxies,species-specific and age-dependent growth responses to warming and drought,anatomical adap-tations,and methodological innovations in isotope analysis and multi-proxy integration.Key findings reveal ENSO/AMO modulation of historical climates,elevation-and latitude-driven variability in tree resilience,contrasting carbon dynamics under stress,and projected habitat shifts for vulnerable species.The issue underscores forests’dual role as climate archives and carbon regulators,offering insights for adaptive management and nature-based climate solutions.Contributions bridge micro-scale physiological processes to macro-scale ecological modeling,advancing sustainable strategies amid global environmental challenges.展开更多
基金supported by the third scientific survey project in Xinjiang(2022xjkk0300)the public welfare geological survey projects initiated by the China Geological Survey(DD20190296,DD20221731).
文摘Addressing global warming,a common change today,requires achieving peak carbon dioxide emissions and carbon neutrality(also referred to as the dual carbon goals).Enhancing research on the carbon cycle is urgently needed as the foundation.Water,a key carrier in the carbon cycle,necessitates investigation into groundwater carbon pools’contribution to atmospheric carbon sinks.This study assessed carbon stocks in the Yinchuan Basin’s soil and groundwater carbon pools.Findings indicate the basin’s surface soils contain approximately 24.16 Tg of organic carbon and a total of 60.01 Tg of carbon.In contrast,the basin’s groundwater holds around 4.90 Tg of carbon,roughly one-fifth of the organic carbon in surface soils.Thus,groundwater and soil carbon pools possess comparable carbon stocks,underscoring the importance of the groundwater carbon pool.Studies on terrestrial carbon balance should incorporate groundwater carbon pools,which deserve increased focus.Evaluating groundwater carbon pools’contributions is vital for achieving the dual carbon goals.
基金the World Climate Recruitment Programme’s (WCRP) Working Group on Coupled Modelling (WGCM)the Global Organization for Earth System Science Portals (GO-ESSP)+2 种基金jointly supported by the National Science Foundation of China (Grant Nos. 41991231, 91937302)the China 111 project (Grant No. B13045)supported by Supercomputing Center of Lanzhou University
文摘The measurement of atmospheric O_(2)concentrations and related oxygen budget have been used to estimate terrestrial and oceanic carbon uptake.However,a discrepancy remains in assessments of O_(2)exchange between ocean and atmosphere(i.e.air-sea O_(2)flux),which is one of the major contributors to uncertainties in the O_(2)-based estimations of the carbon uptake.Here,we explore the variability of air-sea O_(2)flux with the use of outputs from Coupled Model Intercomparison Project phase 6(CMIP6).The simulated air-sea O_(2)flux exhibits an obvious warming-induced upward trend(~1.49 Tmol yr−2)since the mid-1980s,accompanied by a strong decadal variability dominated by oceanic climate modes.We subsequently revise the O_(2)-based carbon uptakes in response to this changing air-sea O_(2)flux.Our results show that,for the 1990−2000 period,the averaged net ocean and land sinks are 2.10±0.43 and 1.14±0.52 GtC yr−1 respectively,overall consistent with estimates derived by the Global Carbon Project(GCP).An enhanced carbon uptake is found in both land and ocean after year 2000,reflecting the modification of carbon cycle under human activities.Results derived from CMIP5 simulations also investigated in the study allow for comparisons from which we can see the vital importance of oxygen dataset on carbon uptake estimations.
文摘Limiting human-caused global warming to a specific level requires achieving net-zero anthropogenic carbon dioxide(CO_(2))emissions,along with strong reductions in other greenhouse gas(GHG)emissions.This means that any remaining anthropogenic CO_(2)emissions must be balanced by an equivalent amount of anthropogenic removals.
基金National Natural Science Foundation of China,No.42276231,No.41871112The Open Research Fund of the State Key Laboratory of Coastal and Marine Engineering,No.LP2518。
文摘Assessing the carbon sink potential of marine aquaculture is critical to fostering sustainable marine economic development and achieving carbon neutrality.This study evaluates the carbon sink potential of four nearshore aquaculture systems in China:floating raft,net cage,pond,and tidal flat.China’s coastal aquaculture shows a dramatic potential range from−5401.28×10^(4)t to 84.65×10^(4)t,acting as both a carbon sink and a source.Floating raft(11.19×10^(4)t to 105.65×10^(4)t)and tidal flat(42.83×10^(4)t to 114.35×10^(4)t)are net carbon sinks.In contrast,net cage(−427.39×10^(4)t to−4.26×10^(4)t)and pond(−5027.91×10^(4)t to−131.09×10^(4)t)are significant net carbon sources.This heterogeneity is driven by differences in species,feed inputs,energy consumption,and management practices.The results highlight the need for targeted low-carbon technologies in high-emission systems to maximize carbon sequestration and mitigate their environmental impacts.This study provides a scientific basis for optimizing carbon management and offers insights for global sustainable aquaculture and carbon neutrality.
基金supported jointly by the National Natural Science Foundation of China(U22A20619,U24A20579,42077455,and 42367008)Western Light Cross-team Program of Chinese Academy of Sciences(XBZG-ZDSYS-202101)+5 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDB40000000)Guizhou Province Science and Technology Innovation Talent Team Construction Project(Qiankehe Talent CXTD(2025)057)Guizhou Provincial Science and Technology Projects(Qiankehe Support[2024]Key 014,[2022]Key 010,[2023]General 219 and ZK(2021)-192)High-level Innovative Talents in Guizhou Province(GCC[2022]015-1)Opening Fund of the State Key Laboratory of Environmental Geochemistry(SKLEG2024202)Guizhou Provincial Science and Technology Subsidies(GZ2019SIG and GZ2020SIG)。
文摘Global climate change has significantly altered the patterns of Annual Snow Cover(ASC),including glaciers,which in turn,have reshaped regional hydrological processes.These changes profoundly impact the weathering rates of continental rocks and their associated carbon sink potential,particularly for silicate(Eq.(1))and carbonate(Eq.(2))rocks under natural conditions[1-3].Low Temperature(Tem)in regions with ASC typically limit the rates of chemical weathering and the occurrence of weathering products.However,as the ASC melts,the chemical weathering processes previously suppressed by ice begin to accelerate progressively[3,4].In regions where ASC diminishes but does not fully expose the ground,increased meltwater alleviates the restrictive effects of solid moisture on regional chemical weathering.
基金supported jointly by the National Natural Science Foundation of China(Grant Nos.42261052,42461047,U22A20619,U24A20579)the Guizhou Science and Technology Association Young Scientific and Technological Talents Supporting Project(Grant No.GASTYESS202401)+6 种基金the Guizhou Provincial Science and Technology Project(Grant Nos.ZK[2023]-464,[2024]-014)the Science and Technology Project of Tongren City(Grant No.[2023]-5)the High-level Innovative Talents in Guizhou Province(Grant Nos.2024-[2022]-051,GCC[2022]015-1)the Western Light Cross Team of the Chinese Academy of Sciences(Grant No.xbzg-zdsys-202101)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB40000000)the Program of Engineering Research Center of Intelligent Monitoring and Policy Simulation of Mountainous Land Space,Higher Education Institutions of Guizhou Province(Grant No.[2023]-045)the Guizhou Provincial University Philosophy and Social Science Laboratory“Qiandong Agricultural(Village)Development and Ecological Governance Laboratory(Pilot Construction)”(Grant No.[2023]-07)。
文摘The karst geological carbon sink,formed through the chemical weathering of carbonate rocks,is an important part of the global terrestrial carbon sink.It has substantial potential and plays a crucial role in the global carbon cycle and regional carbon neutrality efforts.The fifth(AR5)and sixth(AR6)assessment reports of the Intergovernmental Panel on Climate Change(IPCC)have clearly affirmed the existence of geological carbon sinks associated with the chemical weathering of carbonate rocks,stating that carbon capture and geological storage are key mitigation schemes.However,numerous studies have shown that exogenous acids are widely involved during the chemical weathering of rocks,adding complexity to the carbon sequestration process and its driving mechanisms.This increases the uncertainty in assessing the carbon sequestration potential.Therefore,a key task is to accurately estimate the geological carbon sinks generated by the chemical weathering of carbonate rocks to resolve the problem of the global carbon sink loss,balancing the carbon budget,and achieving carbon neutrality.In this review,we examine assessments of the carbonate rocks chemical weathering carbon sink influenced by exogenous acids,focusing on the principles,frameworks and methodologies of carbon sink estimation.We also highlight recent advancements,key influencing factors,and underlying driving mechanisms.Looking ahead,we highlight key challenges in enhancing the accuracy and precision of carbonate rocks chemical weathering carbon sink assessments under the influence of exogenous acids.Addressing these issues will support more informed policy decisions on pathways to global carbon neutrality.
基金supported by the National Key Research and Development Program of China[No.2022YFF1301200]the National Natural Science Foundation of China[No.72074232 and No.42477514]the Major Project of the National Social Science Fund of China[No.22&ZD108].
文摘Cities play a pivotal role in global decarbonization,acting as a critical driver of carbon emissions.Accurately allocating carbon mitigation responsibility(CMR)is essential for designing effective and equitable climate policies.How cities manage carbon leakage across boundaries through supply chains and implement plan of increasing forest carbon sinks are important components for designing a fair and inclusive CMR.However,the combined impact of trade-related carbon leakage and forest carbon sinks on CMR allocation remains poorly understood.Here,we develop an integrated CMR allocation framework that accounts for both carbon leakage and variation of forest carbon offsets.When applied to the cities within the GuangdongeHong KongeMacao Greater Bay Area in China,it becomes evident that the in-clusion of carbon leakage results in substantial alterations in mitigation quotas.Adjustments are observed to vary between±10%and 50%across these cities from 2005 to 2020,a trend that is anticipated to continue until 2035.The redistribution of outsourced emissions through supply chains alleviates the mitigation burden on producer cities by 20e30%.Additionally,accounting for carbon sinks substantially influences CMR allocation,particularly in forest-rich cities,which may see their carbon budgets increase by up to 10%.Under an enhanced climate policy scenario,the growth rate of total mitigation quotas from 2025 to 2035 is projected to decrease by 40%compared to a business-as-usual trajectory,reducing the burden on major producer cities.Our proposed CMR framework provides a robust basis for incentivizing coordinated mitigation efforts,promoting decarbonization in supply chains and enhancement of urban carbon sink capacities.
文摘1.Introduction Carbon neutrality have become a consensus for all of humanity[1,2].As of April,2023,132 countries have announced carbon neutrality targets[3].To achieve carbon neutrality,efforts need to be made from multiple aspects,including decarbonization of the power sector[4,5],electrification of the end-use sectors[6,7],and greening of other industries[8].Ecological carbon sinks play a unique role in these strategies to offset hard-to-reduce greenhouse gas(GHG)emissions by reabsorbing or storing carbon that has already been emitted.
基金Supported by the National Natural Science Foundation of China(Grant Nos.90211016,40638039,40228001,and 40021101)the Key MOE Research Project(Grant No.306019)
文摘Using China's ground observations,e.g.,forest inventory,grassland resource,agricultural statistics,climate,and satellite data,we estimate terrestrial vegetation carbon sinks for China's major biomes between 1981 and 2000.The main results are in the following:(1)Forest area and forest biomass car-bon(C)stock increased from 116.5×10^(6) ha and 4.3 Pg C(1 Pg C=10^(15) g C)in the early 1980s to 142.8×10^(6) ha and 5.9 Pg C in the early 2000s,respectively.Forest biomass carbon density increased form 36.9 Mg C/ha(1 Mg C=10^(6) g C)to 41.0 Mg C/ha,with an annual carbon sequestration rate of 0.075 Pg C/a.Grassland,shrub,and crop biomass sequestrate carbon at annual rates of 0.007 Pg C/a,0.014―0.024 Pg C/a,and 0.0125―0.0143 Pg C/a,respectively.(2)The total terrestrial vegetation C sink in China is in a range of 0.096―0.106 Pg C/a between 1981 and 2000,accounting for 14.6%―16.1%of carbon dioxide(CO_(2))emitted by China's industry in the same period.In addition,soil carbon sink is estimated at 0.04―0.07 Pg C/a.Accordingly,carbon sequestration by China's terrestrial ecosystems(vegetation and soil)offsets 20.8%―26.8%of its industrial CO_(2) emission for the study period.(3)Considerable uncertainties exist in the present study,especially in the estimation of soil carbon sinks,and need further intensive investigation in the future.
基金supported by the National Natural Science Foundation of China (31988102)。
文摘Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ecosystem C monitoring over broad geographic scale to improve terrestrial biosphere models for accurately evaluating terrestrial C budget and its dynamics under various climate change and policy scenarios.
基金supported by the National Basic Research Program of China on Global Change (2010CB950600)the National Natural Science Foundation of China (31021001, 30721140306)'Strategic Priority Research Program-Climate Change: Carbon Budget and Related Issues' of the Chinese Academy of Sciences (XDA05050503)
文摘Forests play a leading role in regional and global carbon (C) cycles. Detailed assessment of the temporal and spatial changes in C sinks/sources of China's forests is critical to the estimation of the national C budget and can help to constitute sustainable forest management policies for climate change. In this study, we explored the spatio-temporal changes in forest biomass C stocks in China between 1977 and 2008, using six periods of the national forest inventory data. According to the definition of the forest inventory, China's forest was categorized into three groups: forest stand, economic forest, and bamboo forest. We estimated forest biomass C stocks for each inventory period by using continuous biomass expansion factor (BEF) method for forest stands, and the mean biomass density method for economic and bamboo forests. As a result, China's forests have accumulated biomass C (i.e., biomass C sink) of 1896 Tg (1Tg=1012g) during the study period, with 1710, 108 and 78 Tg C in forest stands, and economic and bamboo forests, respectively. Annual forest biomass C sink was 70.2 Tg Ca-1 , offsetting 7.8% of the contemporary fossil CO2 emissions in the country. The results also showed that planted forests have functioned as a persistent C sink, sequestrating 818 Tg C and accounting for 47.8% of total C sink in forest stands, and that the old-, mid- and young-aged forests have sequestrated 930, 391 and 388 Tg C from 1977 to 2008. Our results suggest that China's forests have a big potential as biomass C sink in the future because of its large area of planted forests with young-aged growth and low C density.
文摘The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and thermal reservoirs.However,they are increasingly vulnerable to warming and greenhouse gas emissions.
基金National Natural Science Foundation of China,No.42071415National Key Research and Development Program of China,No.2021YFE0106700Outstanding Youth Foundation of Henan Natural Science Foundation,No.202300410049。
文摘China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on evaluating anthropogenic emissions or the natural carbon cycle separately, and few included trade-related(import and export) CO_(2) emissions and its contribution on global warming. Using the Carbon Tracker CT2019 assimilation dataset and China trade emissions from the Global Carbon Project, we found that the change trend of global CO_(2) flux had obvious spatial heterogeneity, which is mainly affected by anthropogenic CO_(2) flux. From 2000 to 2018, carbon emissions from fossil fuels in the world and in China all showed an obvious increasing trend, but the magnitude of the increase tended to slow down.In 2018, the radiative forcing(RF) caused by China's import and export trade was-0.0038 W m^(-2), and the RF caused by natural carbon budget was-0.0027 W m^(-2), offsetting 1.54% and 1.13% of the RF caused by fossil fuels that year, respectively. From 2000 to 2018, the contribution of China's carbon emission from fossil fuels to global RF was 11.32%. Considering China's import and export trade, the contribution of anthropogenic CO_(2) emission to global RF decreased to 9.50%. Furthermore, taking into account the offset of carbon sink from China's terrestrial ecosystems, the net contribution of China to global RF decreased to 7.63%. This study demonstrates that China's terrestrial ecosystem and import and export trade are all mitigating China's impact on global anthropogenic warming, and also confirms that during the research process on climate change, comprehensively considering the carbon budget from anthropogenic and natural carbon budgets is necessary to systematically understand the impacts of regional or national carbon budgets on global warming.
基金supported by the National Natural Scientific Foundation of China(Grant No.40872213)the projects from the China Geological Survey(Grant Nos. 1212010911062 and S-2010-KP03-07-02)+1 种基金from the Ministry of Land and Resources(Grant No.201211086-05)IGCP 598:Environmental Change and Sustainability Karst Systems
文摘Carbonate rock outcrops cover 9%-16% of the continental area and are the principal source of the dissolved inorganic carbon （DIC） transferred by rivers to the oceans, a consequence their dissolution. Current estimations suggest that the flux falls between 0.1-0.6 PgC/a. Taking the intermediate value （0.3 PgC/a）, it is equal to 18% of current estimates of the terrestrial vegetation net carbon sink and 38% of the soil carbon sink. In China, the carbon flux from carbonate rock dissolution is estimated to be 0.016 PgC/a, which accounts for 21%, 87.5%-150% and 2.3 times of the forest, shrub and grassland net carbon sinks respectively, as well as 23%-40% of the soil carbon sink flux. Carbonate dissolution is sensitive to environmental and climatic changes, the rate being closely correlated with precipitation, temperature, also with soil and vegetation cover. HCO3 in the water is affected by hydrophyte photosynthesis, resulting in part of the HCO~ being converted into DOC and POC, which may enhance the potential of carbon sequestration by carbonate rock dissolution. The possible turnover time of this carbon is roughly equal to that of the sea water cycle （2000a）. The uptake of atmospheric/soil CO2 by carbonate rock dissolution thus plays an important role in the global carbon cycle, being one of the most important sinks. A major research need is to better evaluate the net effect of this sink in comparison to an oceanic source from carbonate mineral precipitation.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA11020102)the Joint Fund between the National Natural Science Foundation of China and Shandong Province (Grant No. U1606404)the Program for Aoshan Excellent Scholars of Qingdao National Laboratory for Marine Science and Technology (Grant No. 013ASTP-OS13)
文摘The sinks/sources of carbon in the Yellow Sea(YS) and East China Sea(ECS), which are important continental shelf seas in China, could exert a great influence on coastal ecosystem dynamics and the regional climate change process. The CO_2 exchange process across the seawater-air interface, dissolved and particulate carbon in seawater, and carbon burial in sediments were studied to understand the sinks/sources of carbon in the continental shelf seas of China. The YS and the ECS generally have different patterns of seasonal air-sea CO_2 exchange. In the YS, regions west of 124°E can absorb CO_2 from the atmosphere during spring and winter, and release CO_2 to the atmosphere during summer and autumn. The entire YS is considered as a CO_2 source throughout the year with respect to the atmosphere, but there are still uncertainties regarding the exact air-sea CO_2 exchange flux. Surface temperature and phytoplankton production were the key controlling factors of the air-sea CO_2 exchange flux in the offshore region and nearshore region of the YS, respectively. The ECS can absorb CO_2 during spring, summer, and winter and release CO_2 to the atmosphere during autumn. The annual average exchange rate in the ECS was-4.2±3.2 mmol m^(-2) d^(-1) and it served as an obvious sink for atmospheric CO_2 with an air-sea exchange flux of 13.7×10~6 t. The controlling factors of the air-sea CO_2 exchange in the ECS varied significantly seasonally. Storage of dissolved inorganic carbon(DIC) and dissolved organic carbon(DOC) in the YS and the ECS were 425×10~6 t and 1364×10~6 t, and 28.2×10~6 t and 54.1×10~6 t,respectively. Long-term observation showed that the DOC content in the YS had a decreasing trend, indicating that the "practical carbon sink" in the YS was decreasing. The total amount of particulate organic carbon(POC) stored in the YS and ECS was10.6×10~6 t, which was comparable to the air-sea CO_2 flux in these two continental shelf seas. The amounts of carbon sequestered by phytoplankton in the YS and the ECS were 60.42×10~6 t and 153.41×10~6 t, respectively. Artificial breeding of macroalgae could effectively enhance blue carbon sequestration, which could fix 0.36×10~6–0.45×10~6 t of carbon annually. Organic carbon(OC) buried in the sediments of the YS was estimated to be 4.75×10~6 t, and OC of marine origin was 3.03×10~6 t, accounting for5.0% of the TOC fixed by phytoplankton primary production. In the ECS, the corresponding depositional flux of OC in the sediment was estimated to be 7.4×10~6 t yr^(-1), and the marine-origin OC was 5.5×10~6 t, accounting for 5.4% of the phytoplankton primary production. Due to the relatively high average depositional flux of OC in the sediment, the YS and ECS have considerable potential to store a vast amount of "blue carbon."
基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20619,42077455&42367008)the Western Light Cross-team Program of Chinese Academy of Sciences(Grant No.xbzg-zdsys-202101)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB40000000)the Guizhou Provincial Science and Technology Project(Grant Nos.Qiankehe Support[2024]Key 014,Qiankehe Support[2022]Key 010,Qiankehe Support[2023]General 219&Qiankehe Support ZK(2021)-192)the High-level Innovative Talents in Guizhou Province(Grant No.GCC[2022]015-1)the Opening Fund of the State Key Laboratory of Environmental Geochemistry(Grant No.SKLEG2024202)the Guizhou Provincial Science and Technology Subsidies(Grant Nos.GZ2019SIG&GZ2020SIG)。
文摘The importance of carbonate weathering carbon sinks(CCSs)is almost equal to that of vegetation photosynthesis in the global carbon cycle.However,CCSs have become controversial in formulating carbon neutral policies to deal with global climate problems in various countries,since the carbonate dissolution is reversible.In order to address these controversies,we reviewed recent advances in understanding CCSs and examined the outstanding controversies surrounding them.We have analyzed the five controversies,revealing the existence of CCSs,quantifying their magnitude,clarifying their spatiotemporal pattern,and documenting how they have increased and how they evolved under the background of global change.By addressing these five controversies,we help to bring clarity to the role of CCSs in the carbon cycle of global terrestrial ecosystems.
基金Under the auspices of the National Natural Science Foundation of China(No.52268008)。
文摘This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking and neutrality goals.This research ana-lyzes the spatial characteristics of carbon metabolism from 2000 to 2020 and uses models to identify stable carbon sink areas,positive carbon flow corridors,and carbon sequestration nodes.The goal is to construct a carbon metabolism spatial security pattern(CMSSP)and propose territorial ecological restoration strategies under different development demand scenarios.The results show the following:1)in 2020,the study area’s carbon sink decreased by 8.29×10^(4) t C/yr compared with that in 2010 and by 10.83×10^(4) t C/yr compared with that in 2000.High-carbon sinks were found mainly in mountainous areas,whereas low-carbon sinks are concentrated in urban con-struction land,rural residential areas,and land margins.2)From 2000 to 2020,the spatial security pattern of carbon metabolism tended to be‘high in the middle of the east and west and low in the gulf.’In 2000,2010,and 2020,16 stable carbon sinks were identified.The carbon energy flow density in Guangxi was greater than that in Guangdong and Hainan,with positive carbon flow corridors located primarily in Guangxi and Guangdong.The number of carbon sequestration nodes remained stable at approximately 15,mainly in Guangxi and Hainan.3)Scenario simulations revealed that under the Nature-based mild restoration scenario,the carbon sink rate will reach 611.85×10^(4) t C/yr by 2030 and increase to 612.45×10^(4) t C/yr by 2060,with stable carbon sinks increasing to 18.In the restora-tion scenario based on Anti-globalization,the carbon sink will decrease from 610.24×10^(4) t C/yr in 2030 to 605.19×10^(4) t C/yr in 2060,with the disappearance of some positive carbon flow corridors and stable carbon sinks.Under the Human-based sustainable restoration scenario,the carbon sink area will decrease from 607.00×10^(4) t C/yr in 2030 to 596.39×10^(4) t C/yr in 2060,with carbon sink areas frag-menting and positive carbon flow corridors becoming less dense.4)On the basis of the current and predicted CMSSPs,this study ex-plores spatial ecological restoration strategies for high-carbon storage areas in bay urban agglomerations at four levels:the land control region,urban agglomeration structure system,carbon sink structure and bay structure control region.
基金Supported by the Jiangxi Forestry Science and Technology Innovation Project(Innovation Project[2025]16)the Forestry Science and Technology Promotion Demonstration Project of Central Finance(JXTG[2025]19).
文摘As an important carbon sink resource,urban park green space plays a key role in carbon absorption and storage in the carbon cycle.The existing assessment models provide the basis for evaluating carbon sink potential of urban park green spaces,but it is still necessary to explore a new index system suitable for it.From the perspective of policy environment,relevant cases and policy guidance at home and abroad all support the inclusion of urban park green spaces in carbon sink trading,and the price trend of carbon sink market is good,but it is necessary to balance maintenance costs and benefits.However,technical barriers such as data collection and monitoring still exist,and technological innovation is needed to break through.At the same time,the improvement of social awareness is also crucial,which needs to be achieved through education and publicity and the design of social participation mechanism.In the implementation path,the key steps should be clear in the short term,and the expected results should be displayed.In the long term,the continuous improvement mechanism should be established,and future goals should be set.
基金supported by the Outstanding Action Plan of Chinese Sci-tech Journals(Grant No.OAP-C-077).
文摘Forests play a critical role in mitigating cli-mate change by sequestering carbon,yet their responses to environmental shifts remain complex and multifaceted.This special issue,“Tree Rings,Forest Carbon Sink,and Climate Change,”compiles 41 interdisciplinary studies exploring forest-climate interactions through dendrochro-nological and ecological approaches.It addresses climate reconstruction(e.g.,temperature,precipitation,isotopes)using tree-ring proxies,species-specific and age-dependent growth responses to warming and drought,anatomical adap-tations,and methodological innovations in isotope analysis and multi-proxy integration.Key findings reveal ENSO/AMO modulation of historical climates,elevation-and latitude-driven variability in tree resilience,contrasting carbon dynamics under stress,and projected habitat shifts for vulnerable species.The issue underscores forests’dual role as climate archives and carbon regulators,offering insights for adaptive management and nature-based climate solutions.Contributions bridge micro-scale physiological processes to macro-scale ecological modeling,advancing sustainable strategies amid global environmental challenges.
