Carbon Storage In Areas Research Articles

Spatio-temporal Evolution and Multi-scenario Simulation of Carbon Storage in Karst Regions of Central Guizhou Province：Taking Puding County as An Example

Regional land use change is the main cause for the change in karst carbon storage. It is important to analyze the spatial and temporal evolution and future spatial distribution trends of carbon storage in typical counties in central Guizhou's karst region， such as Puding County， to improve regional carbon storage， optimize land ecological security patterns， and promote low-carbon sustainable urban development. The PLUS-InVEST model was coupled， based on the interpreted land use data and future land prediction， the spatial and temporal evolution characteristics of land use change and carbon storage in Puding County from 1973 to 2020 were inverted， and the spatial pattern evolution of land use and carbon storage change under different scenarios in 2060 were simulated and predicted. The results showed： ① from 1973 to 2020， the overall carbon storage in Puding County increased by 6.61×105 t， showing an upward trend. The spatial distribution showed a significant increase in the northeastern and southwestern parts of Puding County and a significant decrease in the south-central parts. The change was due to the increase in carbon storage in dryland to shrubland and forest land and the decrease in carbon storage in areas where paddy fields are converted to construction land. ② The land use change in Puding County in the historical period was mainly reflected in the continuous expansion of construction land and the increased fluctuation of the proportion of forest land and shrub forest land， and the change in land use in different scenarios projected in 2060 retained the change characteristics of the historical period. ③ In 2060， the carbon storage in Puding County under the scenarios of natural evolution， ecological protection， and economic development increased by 2.93×105， 5.40×105， and 1.11×105 t， respectively， compared with that in 2020. Of these， the increase in ecological protection scenarios was the most significant， with the transfer of dryland to shrubland being the main reason for the increase in regional carbon sequestration capacity. These results can serve as a scientific reference for land use management decisions and the formulation of emission reduction and sink increase policies in Puding County. The future land use planning of karst areas should be guided by the goal of "carbon neutrality" in 2060， take appropriate ecological protection measures， strictly control the rapid expansion of construction land to paddy fields， optimize the land use structure， and effectively improve the level of regional carbon storage.

From savanna to suburb: Effects of 160 years of landscape change on carbon storage in Silicon Valley, California

Landscape changes such as urbanization can dramatically affect the provision of ecosystem services such as carbon storage. However, while cities have been shown to store substantial amounts of carbon in soils and vegetation, we have little information from long-term studies about how contemporary carbon storage in urban areas compares to carbon storage in the natural ecosystems that characterized these landscapes prior to urbanization. We used historical archival sources and land-cover data to quantify and map historical tree carbon storage in the now-urban Santa Clara Valley, California, USA prior to substantial Euro-American modification (ca. 1850) and to analyze change in the amount and distribution of carbon storage over the past ca. 160 years. We estimate that total tree carbon storage in the study area was ~784,000 to 2.2 million Mg (13.6–38.1 Mg C/ha) when the region was characterized by oak savanna and woodland habitats, compared to ~895,000 Mg C (15.5 Mg C/ha) today. This represents a non-significant gain of 14% to a significant loss of 60% depending on scenario. We also demonstrate changes in the spatial distribution of carbon on the landscape, as losses in carbon storage in areas of former oak woodland were partially offset by gains in carbon storage in historical habitat types that historically had few or no trees. This challenges the hypothesis that aboveground carbon storage increases with urbanization in Mediterranean-climate ecosystems due to irrigation and tree planting. Our study demonstrates the utility of using pre-1900s historical sources to reconstruct changes in ecosystem services such as carbon storage over century time scales.

ANÁLISE DA ESTRUTURA E BIOMASSA FLORESTAL DE ÁREAS DE COLHEITA DE FRUTOS DE JUÇARA (<i>Euterpe edulis</i> Mart.) NO LITORAL NORTE E SERRA DO MAR - SP

Os padrões de distribuição e estoque do carbono em áreas manejadas de Mata Atlântica ainda são pouco conhecidos. Visando compreender o papel destas áreas na fixação de carbono, procurou-se caracterizar a estrutura florestal e estimar a biomassa acima do solo em áreas de colheita de frutos de juçara (Euterpe edulis Mart.). O trabalho foi realizado em áreas alteradas nas quais foi introduzido o manejo de frutos de juçara, no Parque Estadual da Serra do Mar - SP e no seu entorno, abrangendo as fitofisionomias Floresta Submontana e Floresta Montana. Para representar todas as diferentes situações em que é praticado o manejo, foram selecionadas oito áreas e em cada uma foi alocada uma parcela de 10 x 100 m dividida em subparcelas de 10 x 10 m, nas quais foram inventariados todos os indivíduos arbóreos (árvores, juçaras, bananeiras e pteridófitas) com DAP (diâmetro a altura do peito) > 4,8 cm. As áreas estudadas foram caracterizadas como Florestas Secundárias e como sistemas de Consórcio de Banana e Juçara. A biomassa encontrada nas parcelas estudadas variou de 47,9 a 279,9 Mg ha-1. As Florestas Secundárias apresentaram maior biomassa que os sistemas de cultivo em Consórcio de Banana e Juçara, sendo as árvores responsáveis pela maior parte dessa biomassa. O manejo dos frutos da palmeira juçara para a produção de polpa alimentar representa uma alternativa sustentável à extração ilegal do palmito na região, diversificando os cultivos de banana existentes, agregando valor às florestas e aumentando o estoque de carbono em áreas de Mata Atlântica com sistemas agroflorestais.

我国东北天然林保护工程区森林植被碳储量研究

以东北天然林保护工程区森林生态系统为对象，通过对其主要森林类型进行调查，探讨天保工程经营区划对森林植被固碳现状的影响，并结合已有的东北林区生物量与蓄积量数据库，建立了东北林区主要树种组的生物量-蓄积量回归模型，然后以第7次森林资源清查为基础，对东北天保工程区森林植被碳储量进行估算，以期为全国森林生物量的估算和天保工程的评估提供参考。结果表明，不同经营区之间（重点公益林、一般公益林和商品林）森林植被碳密度的差异并不显著，这可能与天然林保护工程实施初期经营区划的标准、样地的选择以及天保工程实施过程中粗放的管理方式有关。东北天保工程区森林植被碳储量为1045 TgC，占东北、内蒙古三省森林植被总碳储量的68%；工程区以天然林为主，占工程区总植被碳储量的97%。工程区森林植被平均碳密度为41 Mg/hm²，较东北、内蒙古三省平均植被碳密度高14%；工程区植被碳密度随林龄的增加逐渐增大，由幼龄林的13 Mg/hm²到过熟林的63 Mg/hm²。因此，继续加强天然林保护工程的实施，提高其林分质量，这对未来我国森林碳汇潜力的增加和森林的可持续发展都具有重要的意义。;The Natural Forest Protection Program (NFPP), which aims at protecting ecological resources and achieving sustainable forest management, has been implemented for 10 years in Northeast China. Under the program forest ecosystems in the region have been divided into three management areas-Key conservation, General conservation and Commercial forest. Each of these three types of forest land is subject to different management measures (protecting or logging). Estimating carbon storage of forest vegetation in these areas is important both for understanding the capacity of forests in the Northeast region for carbon sequestration and as an aid to assessing the effectiveness of the NFPP in meeting its goals. To address this important need, this study selected five major forest types in the Northeast forest region-larch forest, birch forest, coniferous mixed forest, broadleaved mixed forest, coniferous and broadleaved mixed forest. Each forest type was divided into four age classes-young, mid-aged, premature and over mature forest. Tree biomass was calculated through species-specific allometric equation models based on field measurement in the Daxing'anling, Xiaoxing'anling and Changbai mountains. At the same time, an dataset on biomass and volume of the main forest types in the Northeast forest region was established based on existing data from former studies. Since some studies have found that the relationship between forest biomass and volume fits relatively well within a liner regression framework, this study utilized this two data sources noted above to establish biomass-volume line regression models of the main tree species groups in the Northeast, focusing primarily on the five major forest types identified above. Forest biomass carbon storage in areas under the NFPP in the Northeast region was subsequently estimated based on data from the 7th National Forest Resource Inventory. Results showed that forest biomass carbon storage based on field measurement did not varied significantly with management areas, which likely reflects both the classification standard for the management areas and the relatively short period since the NFPP have been implemented. On the other hand, forest biomass carbon storage of lands under the NFPP was 1045 TgC, which accounted for 68% of total forest biomass carbon storage in the Northeast provinces of Jilin, Heilongjiang and Inner Mongolia. Moreover, forest biomass carbon density of lands under the program (41 Mg/hm²) exceeded that of the average biomass carbon density in Northeast provinces (36 Mg/hm²). Simultaneously, in the lands of the NFPP, forest biomass C density increased with forest age class, from 16.4 Mg/hm² in young to 63.0 Mg/hm² in over mature forest, thus the relative large areas of young and mid-aged forests (together accounted for 61% of total forest area), implying its great C sequestration potential in the future. In addition, forest biomass carbon storage was dominated by natural forest, which accounted for 97% of total biomass carbon storage under the NFPP. On an overall basis, the Natural Forest Protection Program acts an important role in the Northeast forest region, and it should be played an increasingly important role in forest ecosystem carbon sequestration and sustainable forest management in the next implemented decade.