Carbon Sequestration Dynamics in Urban-Adjacent Forests: A 50-Year Analysis

Many countries have made major commitments to carbon sequestration through reforestation under the Paris Climate Agreement, and recent studies have illustrated the potential for large amounts of carbon sequestration in tropical second-growth forests. However, carbon gains in second-growth forests are threatened by non-permanence, i.e. release of carbon into the atmosphere from clearing or disturbance. The benefits of second-growth forests require long-term persistence on the landscape, but estimates of carbon potential rarely consider the spatio-temporal landscape dynamics of second-growth forests. In this study, we used remotely sensed imagery from a landscape in the Peruvian Amazon to examine patterns of second-growth forest regrowth and permanence over 28 years (1985–2013). By 2013, 44% of all forest cover in the study area was second growth and more than 50% of second-growth forest pixels were less than 5 years old. We modeled probabilities of forest regrowth and clearing as a function of landscape factors. The amount of neighboring forest and variables related to pixel position (i.e. distance to edge) were important for predicting both clearing and regrowth. Forest age was the strongest predictor of clearing probability and suggests a threshold response of clearing probability to age. Finally, we simulated future trajectories of carbon sequestration using the parameters from our models. We compared this with the amount of biomass that would accumulate under the assumption of second-growth permanence. Estimates differed by 900 000 tonnes, equivalent to over 80% of Peru’s commitment to carbon sequestration through ‘community reforestation’ under the Paris Agreement. Though the study area has more than 40 000 hectares of second-growth forest, only a small proportion is likely to accumulate significant carbon. Instead, cycles between forest and non-forest are common. Our results illustrate the importance of considering landscape dynamics when assessing the carbon sequestration potential of second-growth forests.

The carbon sequestration potential is affected by cropping system and management practices, but soil organic carbon (SOC) sequestration potential under fertilizations remains unclear in north China. This study examined SOC change, total C input to soil and, via integration of these estimates over years, carbon sequestration efficiency (CSE, the ratio of SOC change over C input) under no fertilization (control), chemical nitrogen fertilizer alone (N) or combined with phosphorus and potassium fertilizers (NP, NK, PK and NPK), or chemical fertilizers combined with low or high (1.5×) manure input (NPKM and 1.5NPKM). Results showed that, as compared with the initial condition, SOC content increased by 0.03, 0.06, 0.05, 0.09, 0.16, 0.26, 0.47 and 0.68 Mg C ha-1 year-1 under control, N, NK, PK, NP, NPK, NPKM and 1.5NPKM treatments respectively. Correspondingly, the C inputs of wheat and maize were 1.24, 1.34, 1.55, 1.33, 2.72, 2.96, 2.97 and 3.15 Mg ha-1 year-1 respectively. The long-term fertilization-induced CSE showed that about 11% of the gross C input was transformed into SOC pool. Overall, this study demonstrated that decade-long manure input combined with chemical fertilizers can maintain high crop yield and lead to SOC sequestration in north China. © 2016 Society of Chemical Industry.

Sea-level rise enhances carbon accumulation in United States tidal wetlands

Potential for soil carbon sequestration of eroded areas in subtropical China

This study explores renovation strategies for green spaces in aging residential communities in cold regions, with a particular focus on enhancing carbon sequestration capacity and residents’ well-being. Under the framework of the “dual carbon” goals, a combination of literature analysis and resident surveys reveals that (1) the existing layouts of green spaceand plant selections have not fully considered their carbon sequestration potential, leaving significant room for optimization; (2) low outdoor temperatures, the lack of heating facilities, and monotonous winter landscapes contribute to reduced green space utilization, limiting outdoor activities and diminishing the health benefits of green spaces; and (3) the integration of glass sunrooms with renewable energy systems, such as photovoltaic power generation, can effectively improve winter green space utilization, regulate micro climates, and enhance vegetation-based carbon sequestration while also providing residents with comfortable spaces for social interaction and wellness activities. The findings indicate that scientifically optimizing green space layouts, selecting plant species with high carbon sequestration potential, and incorporating climate-adaptive architectural designs can significantly enhance the ecological value of green spaces and residents’ quality of life. It is recommended that future community renewal initiatives integrate green technologies, policy support, and interdisciplinary collaboration to promote low-carbon and livable urban development.

Foreword PART I. Urban Ecosystems and Climate Change 1. Urban Ecosystems and Climate Change R. Lal 2. Adapting Urban Land Use in a Time of Climate Change Optimising Future Land-use Patterns to Decrease Flood Risks E.van Leeuwen, E. Koomen 3. Comparison of Methods for Estimating Carbon Dioxide Storage by Sacramento's Urban Forest E. Aguaron, E.G. McPherson 4. Terrestrial Carbon Management In Urban Ecosystems And Water Quality K. Lorenz, R. Lal PART II. Urban Forests 5. Carbon Stocks in Urban Forest Remnants: Atlanta and Baltimore as Case Studies I. D. Yesilonis, R. V. Pouyat 6. Urban Trees for Carbon Sequestration B.C. Scharenbroch 7. Carbon Storage in Some Urban Forest Soils of Columbus, Ohio, USA K. Lorenz, R. Lal PART III. Turfgrass and Home Lawns 8. Carbon Dynamics and Sequestration in Urban Turfgrass Ecosystems Y. Qian, R. Follett 9. Carbon sequestration potential in urban soils S. Brown, E. Miltner, and C. Cogger 10. Carbon Sequestration in Turfed Landscapes: A Review E.A. Guertal 11. Microbial Control of Soil Carbon Accumulation in Turfgrass Systems W. Shi, D. Bowman, T. Rufty 12. Using Soil Health Indicators to Follow Carbon Dynamics in Disturbed Urban Environments- A Case Study of Gas Pipeline Right-of-Way Construction R. R. Schindelbeck, H. M. van Es 13. Carbon Sequestration in Golf Course Turfgrass Systems and Recommendations for the Enhancement of Climate Change Mitigation Potential A. L. Selhorst, R. Lal 14. Modeling Carbon Sequestration in the U.S. Residential Landscape G. Zirkle, R. Lal, B. Augustin, R. Follett PART IV. Current Trends in Urban Ecosystems 15. Improving Soil Quality for Urban Agriculture in the North Central U.S. J. Beniston, R. Lal 16. Carbon Cycle of Urban Ecosystems G. Churkina 17. Legacy Effects of Highway Construction Disturbance and Vegetation Management on Carbon Dynamics in Forested Urban Verges T. L. L. Trammell, M. M. Carreiro PART V. Sustainable Management of Urban Ecosystems 18. Global Urbanization and Demand for Natural Resources C. Yeh, S. Huang 19. Toward Greening of Urban Landscapes R. Lal

<p>In order to meet the dual challenges of providing for a growing global population and mitigating climate change effects, it is necessary to consider how urban areas can grow while achieving carbon neutrality, which is a complex and difficult task. It requires increased understanding of carbon dynamics in the coupled urban social-ecological systems, including process-level understanding and distinction of natural and human-perturbed carbon exchanges and their interactions. A better understanding of these complex systems and processes could, for example, facilitate enhanced use of nature-based solutions (NBS) to help mitigate and offset the greenhouse gas (GHG) emissions of urban regions. This paper addresses part of this challenge, aiming to further understanding of the complex interactions between urban growth and GHG emissions implied by associated land use changes, including the influence of water bodies within the urban region on the carbon source-sink dynamics.</p><p> </p><p>The study involves a comprehensive analysis of the land-use related GHG emissions and removals (through carbon sequestration) in the urban region of Stockholm County in Sweden, which is currently experiencing large urban growth and rapid population growth. Stockholm County includes large urban areas, forested areas (both old and young preserved natural forests and managed forestry), farmlands, some wetlands, and a number of smaller towns and semi-urban areas. Geographically, much of the county is located on the Stockholm Archipelago – a series of islands in the Baltic Sea – and the remainder is dominated by many lakes, including Lake Mälaren, which is Sweden’s third largest lake and the main water supply for the capital city Stockholm. The water coverage prevailing in the county allows for investigation of its effects in combination and relation to the variable and changing urban and other land cover distribution on the regional GHG emissions and sequestrations. These effects may be considerable and are addressed in this study.</p><p> </p><p>Results include an inventory of existing and planned land uses in Stockholm County, and the GHG emissions or sequestration potentials associated with each of these. The land uses include urban and semi-urban areas, different types of natural and cultivated vegetation, agriculture, forestry, water bodies and wetlands. The study provides a map of Stockholm County’s GHG emission and sequestration potential, which is further analysed to advance our understanding of how future development in the county can be shaped to effectively minimize urban GHG emissions and maximize carbon sequestrations. The inclusion of water bodies in this GHG inventory proved to be particularly interesting; while lakes and other water bodies are often considered as ‘blue’ nature-based solutions (NBS) for maintaining and providing a number of ecosystem services in urban regions, our results indicate the lakes in Stockholm County as considerable sources of GHG emissions. The contribution of inland waters to the regional GHG emissions emphasizes the need and importance of improving rather than deteriorating the regional carbon sequestration potential in the urbanization process. This can be achieved by using and enhancing other types of NBS, such as rehabilitation of green areas like forests, in order to achieve carbon neutrality in this urban region.</p>

BackgroundGiven the large bamboo resource base with considerable potential to act as an important carbon sink, Ethiopia has included bamboo in the national Reducing Emissions from Deforestation and Forest Degradation and enhancing forest carbon stocks (REDD+) and Clean Development Mechanisms (CDM) programs. However, little is known about the carbon stock and sequestration potential of bamboo forests. As a result, this research was conducted to quantify the carbon sequestration and storage capacity of Oxytenanthera abyssinica forests in the Lower Beles River Basin, northwestern Ethiopia. To this end, a total of 54 circular plots, each measuring 100 m2 with a radius of 5.64 m, were established to conduct the inventory in Assitsa and Eddida bamboo forests, the typical bamboo sites in Lower Beles River Basin. Biomass accumulation of bamboo was estimated using an allometric equation based on diameter at breast height (DBH) and age. Soil samples were taken from two different soil depths (0–15 and 15–30 cm) to determine soil organic carbon.ResultsResults indicate that the mean biomass of the bamboo forests in the study area accounted for about 177.1 pm 3.1 Mg ha−1. The mean biomass carbon and soil organic carbon stock of the bamboo forests were 83.2 pm 1.5 Mg C ha−1 and 70 pm 1.7 Mg C ha−1, respectively. Therefore, the mean carbon stock of the O. abyssinica bamboo forests was 152.5 pm 2.5 Mg C ha−1 to 559.8 pm 9.0 ton CO2 ha−1.ConclusionThis study highlights the importance of assessing bamboo’s carbon stock and sequestration potential for enhancing its role in climate change mitigation and sustainable resource management. The O. abyssinica bamboo forests of the study area have significant carbon stock and sequestration potential. Therefore, sustainable management of these crucial vegetation resources will enhance their role in providing ecosystem services, including climate change mitigation.

2 - Crop management practices for carbon sequestration

Potential carbon sequestration in China’s forests

Mangrove ecosystems are net carbon sinks. These have high carbon sequestration potential in soil, sediments, and water column. The soil organic carbon (SOC) which is protected by the aggregates is called the slow pool. In this pool, the organic matter is partially decomposed. Carbon which is present between aggregates is called inter-particulate organic carbon and the carbon which is present within aggregates is called intra-particulate organic carbon. It is also called particulate organic matter carbon (POM-C). Many reports have suggested that macroaggregates (>250μm) provide less protection to carbon in comparison to micro aggregates (<250μm), to decomposition. The present paper depicts the comparative analysis of particulate organic carbon (POC) sequestration and soil aggregate stability in mangrove and rice ecosystem of the Sundarban delta. In our study seven different sites were selected based on the degradation status of mangroves from 1930 to 2013 by National Remote Sensing Agency (NRSA), Hyderabad in Sagar Island, Sundarban, India. In order to estimate the POC sequestration and soil aggregate stability aggregate fractions of different sizes were extracted from the sample with the help of Yoder apparatus. POC in soil aggregates of each class were estimated with the help of C/N analyser. Samples were collected from all the two depths (0-15 cm and 15-30 cm) of all sites. To estimate the aggregate stability Mean weight diameter (MWD) was calculated. In mangrove, The average mean weight diameters (MWD) of soils were in between 0.088 to 0.145 mm whereas in rice it was in between 0.120 to 0.438 mm among the seven different sites. This shows that more aggregate stable soil is under the rice system than that of mangrove system. The soils of the top layer had more aggregate stability than the sub-soil in both the (mangroves and rice) systems. The MWD of soil aggregate under the rice system was higher than in the mangroves system. Macroaggregate are generally formed through the cementation of microaggregates. Earlier studies have suggested that aggregate transformation is strongly regulated by microbial activity. Fungal hyphae physically bind the microaggregate together to form macroaggregate and it also stabilize the contents present in microaggregate. This paper investigates the significant impact of all three factors (i.e. ecology, site and depth) on the aggregate stability and POC sequestration.

Carbon sequestration (CS) has been increasingly viewed as one of the crucial issues/strategies to address the challenging issues of global warming led climate change effects besides imparting sustainability to productivity. In agricultural land use systems, increased CO2 emission into the atmosphere is through repeated and frequent cultivation of croplands, crop residues, biomass burning, shifting cultivation, cultivation of low biomass producing crop cultivars, land degradation, deforestation, etc. The results of current review revealed that agricultural soils have lost about 30–75% of their inherent soil organic carbon (SOC) pool which is quite alarming. The U.N. panel (IPCC) in its current report published that to contain warming at 1.5oC, there will be a need to reduce the global net CO2 emissions (manmade) by about 45% by the year 2030 from 2010 levels and further to reach ‘net zero’ by 2050. The potential of carbon sequestration with cautious management of world cropland include 0.08±0.12 Pg/yr by erosion control, 0.02±0.03 Pg/yr by preservation of harshly problematic/degraded soils, 0.02±0.04 Pg/yr by repossession of salt-affected soils, 0.15±0.175 Pg/yr by taking up of minimum/conservation tillage and crop left-over administration, 0.18±0.24 Pg/yr by execution of better cropping system and 0.30±0.40 Pg/ yr as C balance via biofuel production. The total potential of carbon sequestration by the world cropland is about 0.75±1.0 Pg/yr. Each 1 Mg/ha rise in soil organic carbon pool in the root zone under the soil would enhance yields of crops by 20–70 kg/ha in case of wheat, 10–50 kg/ha in rice, and 30–300 kg/ha in corn, augmenting production of cereals and legumes in the developing countries by 32 and 11 million Mg/yr, respectively. Therefore, CS apart from mitigating global warming potential also succors the farming community and the nation in advancing food security on sustainable basis.

Wetlands are among the most important natural resources on earth. They provide a potential sink for atmospheric carbon but if not managed properly, they become a source of green house gases. However, only limited studies have been conducted to assess the roles and potentials of wetlands in carbon sequestration. Wetlands occupy approximately 5% of the total land area in Nepal, some of these being of international importance. However, there are major knowledge gaps in accurately quantifying carbon stored in them, as well as their carbon sequestration potential. Therefore, further research is needed to better understand the processes of carbon sequestration in wetland vegetation and soils. Key words: wetland, sink, carbon sequestrationDOI: 10.3126/jowe.v2i1.1855 Journal of Wetlands Ecology, (2009) vol. 2, pp 41-45

Carbon sequestration in soils has a huge potential to decrease the rate of CO2 emission to the atmosphere. However, little is known about Soil Organic Carbon (SOC) stock and fluxes in savannas. This study quantified the SOC of major plant communities in the southern guinea savanna ecological zone of Nigeria to determine their carbon sequestration potential for climate change mitigation. Field and laboratory procedures were employed to estimate carbon stock. Soil samples were collected by resampling from 40 permanent sampling plots for the years 2013, 2017, and 2021, respectively. Eighty composite soil samples were taken at two depths (0-15cm and 15-30cm). SOC concentration was estimated in the laboratory using the wet-oxidation Walkley-Black method. Findings revealed that between 2013 and 2021, the mean bulk density at 0–15 cm increased from 1.29 to 1.38 g cm-3, while at 15-30cm depth ranged from 1.30 to 1.36 g cm-3, signifying an increasing trend of soil compaction. Conversely, the mean SOC at 0–15 cm decreased from 20.11 to 14.06 Mg ha-1 while 15-30cm ranged from 15.84 to 11.92 Mg ha-1, implying carbon loss. The mean SOC concentration was mostly higher in the 0-15 cm layer than in the 15-30 cm layer. Savanna Woodland recorded the highest SOC (23.41 Mg ha-1) in 2013, while the Recent fallow land recorded the lowest (7.25 Mg ha-1) in 2021. Between 2013 and 2021, carbon emissions occurred at an annual loss rate of 8.87 Mg ha-1 yr-1. It was concluded that the restoration of the various plant communities has the potential to sequester about 79.84 Mg ha-1 of SOC at an annual rate of 8.87 Mg ha-1, which will provide effective climate change mitigation. This study recommends sustainable management practices for soil carbon sequestration, such as forest protection, fire management, afforestation, the use of organic fertilizers, and soil amendments.

Assessing spatiotemporal variations of forest carbon density using bi-temporal discrete aerial laser scanning data in Chinese boreal forests