Soil Carbon Changes Research Articles

Changes in Soil Carbon Stocks and Vegetative Indices in the Transitional Phases from Degraded Grassland to an Agroforestry System in the Cerrado Region, Brazil

ABSTRACT Soil organic matter (SOM) is a key soil property used to predict the impacts of land-use changes as well as to indicate soil health status. The vegetative indices (VI) derived from remote-sensing data, such as soil adjusted vegetation index (SAVI), normalized difference vegetation index (NDVI) and normalized difference moisture index (NDMI) are important indices reflecting crop growth and biomass. They can be related to soil organic carbon changes in large-scale environments. However, there is little information in the literature about the relationship between VI and soil carbon changes over the transition of different farming practices from degraded grassland to an agroforestry system. This study aimed to determine the relationship between soil C stocks and VI over the transition of degraded grassland (DGL) to agroforestry (AgrfS) in the Brazilian Cerrado. Soil organic stocks, NDVI, SAVI and NDMI were measured from 2011 to 2015, when the area passed from a low-productivity grassland, followed by a crop-pasture intercropping system and an agroforestry system. The transitional phases from degraded grassland to agroforestry system promoted surprisingly large gains in soil carbon stocks, ranging from 41.7 Mg C ha−1 in DGL to 68.4 Mg C ha−1 in AgrfS. Similar to soil carbon stocks, the mean VI values increased over the years from DGL to AgrfS, indicating the importance of vegetation indices to predict soil carbon stocks changes over the restoration of degraded grasslands.

Impacts of dairy forage management on soil carbon change and net-zero accounting.

The US Dairy Industry has pledged to achieve net zero greenhouse gas emissions (GHG) by 2050, but reliance on corn (Zea mays L.) silage as a primary forage source undermines progress toward this goal. Soils managed for corn silage production are a significant source of carbon (C) emissions to the atmosphere, with the soil C losses ranging from 3.7 to 7.0 Mg C ha-1 yr-1 (13.5 to 25.6 Mg CO2 ha-1 yr-1) reported in the literature. However, biogenic emissions from soil C loss are not typically represented within C-footprints or life cycle inventories. Using an example dairy farm, we demonstrate that including emissions associated with soil C losses under dairy forage production can increase the C-footprint of milk nearly 2-fold. We suggest that this approach represents a more accurate estimate of the emissions impact of milk production, and that gains in the GHG efficiency of milk have come, in part, at the expense of soil C where forage rotations are predominated by silage corn. The C balance of forage production systems can likely be improved with advanced manure management technologies and application strategies that return more manurial C to the soil while minimizing N and P loading. However, we argue that more extensive changes to forage cropping systems will also be required. Expanding the role of perennials and winter annual crops in forage rotations; breeding forages with greater yield, persistence, and deeper more extensive root systems; and additional creative solutions to retain more plant-derived C in soils are necessary to balance soil C budgets and achieve net-zero emissions targets.

Measuring and Modeling Soil Carbon Changes on Dutch Dairy Farms

Soil carbon sequestration is one of the pathways for the dairy sector to mitigate climate change. Soil carbon measures have been reviewed extensively, including estimates of their impacts on regional or national scales. Eventually, these measures are to be implemented by the farmers themselves, justifying an assessment at farm and field level. Here, we used soil and management data from 96 fields on nine dairy farms to quantify annual stock changes under current management and the effect of several carbon measures on soil carbon sequestration in relation to farm configurations. The fields were in use as permanent grassland or grass-arable rotation with forage maize or other crops. We compared the observed changes in the soil layer of 0–25 cm with the RothC simulated changes, and we also simulated the effect of carbon measures on soil carbon stocks. We found a moderate (R2 = 0.30) relation between simulated and measured soil carbon changes. Factors that contribute to the uncertainties are the estimates of field-specific carbon inputs from crop residues and manures, especially for farms that temporarily exchange land with other farmers. The current standard agronomic soil sampling program is unable to reliably detect soil carbon changes at a farm or field level. The annual changes in simulated soil carbon were negatively related to the initials carbon stocks, which has important implications for the potential of additional carbon storage. Therefore, we propose an indicator that expresses the current soil carbon stock in relation to the location-specific maximal achievable carbon stock for permanent grassland that receives an equivalent of 170 kg nitrogen per ha per year from animal manure. This can be used to compare farms and indicate whether a farmer’s focus should be on additional carbon storage or the protection of existing stocks. The simulation of carbon measures showed that the proportion of grassland is key in soil carbon storage.

Carbon benefits through agroforestry transitions on unmanaged fallow agricultural land in Hawaiʻi

There are growing efforts to incorporate agroforestry into ecosystem service incentive programs. Indigenous and other place-based multi-strata agroforestry systems are important conservation and agricultural strategies, yet their ecosystem services, including carbon sequestration benefits, have received little research attention. To fill this gap, we draw on interviews with agroforestry practitioners and ecosystem service modeling in Hawaiʻi to: (1) create future scenarios of where fallow unmanaged agricultural and non-native dominated conservation lands could be transitioned to multi-strata agroforestry under current and future climates; and (2) quantify the potential above-ground carbon and soil carbon benefits and tradeoffs of transitions across these scenarios. We found that about half of unmanaged fallow agricultural lands, representing >1,500 km2 , was suitable for agroforestry transitions under current rainfall and over a third, representing >1,200 km2, remained suitable under a dry climate change scenario, RCP 8.5 mid-century. Mean above-ground carbon in modeled agroforestry systems was estimated to be 92–125 Mg C ha-1 (337–458 Mg CO2 ha-1) with ~75% of the potential restoration area projected to significantly increase above-ground carbon storage. Considering both above-ground and soil carbon, overall carbon benefits are expected across over a third of the potential restoration area with just 5% of the area with expected overall losses. These results provide evidence for potential carbon hotspots for agroforestry transitions, as well as to the need for further study of soil carbon changes with multi-strata agroforestry transitions across varying climates and soil types. With potential carbon sequestration similar to or greater than that of native forest restoration, restoration through agroforestry represents an important pathway to achieving carbon benefits through multi-benefit forest-agricultural systems on large areas of unmanaged agricultural lands, offering a pathway to support inclusive and effective natural climate solutions.

Soil carbon and wood decay models in Nigeria’s Niger Delta environment

Decaying of wood is a major factor in modelling global carbon emissions and their effect on climate change. When not properly considered, trees used in urban greening have been observed to cause hazards and do a disservice in terms of carbon storage due to their degradation. This degradation process is aided by species properties and climatic and biological factors, but the quantitative characteristics of this process on commonly used avenue trees in Nigeria are scarce. The decay rate of wood-block samples of six commonly used avenue trees (Azadirachta indica, Gmelina arborea, Delonix regia, Casuarina equisetifolia, Musanga cecropiodes, and Ficus elastica), as well as soil carbon changes beneath the wood blocks, were monitored under natural varying climatic conditions (Soil temperature, air temperature, relative humidity) and incidence of termite attack over a period of 16 weeks. Soil and air temperature showed a quadratic trend with decay rate, with p-values less than 0.05 and 0.10, respectively, while density and incidence of termite attack were negatively linear (p<0.05) and positively linear (p<0.01), respectively. Among the species, D. regia had the highest coefficient for predicting decay rate. Soil depth and wood density were significant predictors of soil carbon accumulation from decaying wood samples. Soil temperature and other climatic variables of a region should be considered for various tree planting and management projects to discourage the selection of trees with a high decay rate and carbon loss in the area, such as D. regia.

Natural tree colonisation of organo‐mineral soils does not provide a net carbon capture benefit at decadal timescales

Abstract Tree cover is often increased with the aim of increasing ecosystem carbon sequestration and mitigating climate change. However, when planting trees in ecosystems with carbon‐rich soils, soil disturbance during ground preparation can cause soil carbon losses not counteracted by tree carbon gains at the decadal timescales relevant to climate change mitigation targets. Tree establishment via natural colonisation, which does not involve soil disturbance, might prevent these soil carbon losses, but this is unknown. We measured soil, ground vegetation, and tree carbon stocks and tree inputs along an 8 metre transect from single, native, 25‐year‐old naturally colonised trees (Pinus sylvestris or Betula spp.) onto Calluna vulgaris‐dominated moorland, at sites with carbon‐rich organo‐mineral soils in the Cairngorms, UK. Along the transect away from the tree, organic soil carbon stocks increased from 4.0 kg C m−2 at 0.5 m, to 6.0 kg C m−2 at 8 m. Meanwhile, carbon stocks in the top 10 cm of the mineral soil horizon, 3.6 kg C m−2, did not vary. Ground vegetation carbon stocks increased only slightly, from 1.0 kg C m−2 at 0.5 m, to 1.3 kg C m−2 at 8 m. Mean carbon stock per tree was 32.4 kg, so overall, sparse natural colonisation resulted in no net ecosystem carbon gain. Policy implications: Sparse natural colonisation of carbon‐rich soils by low biomass trees might not result in net ecosystem carbon gains at decadal timescales, and instead lead to unforeseen soil carbon losses. Soil carbon changes should be taken into account when quantifying the climate change mitigation potential of natural colonisation.

Soil Organic Carbon Research and Hotspot Analysis Based on Web of Science: A Bibliometric Analysis in CiteSpace

Soil carbon sequestration is an important process of the terrestrial carbon cycle, and even slight changes in soil carbon will trigger drastic variations in the global carbon pool. In this study, we used the CiteSpace software to analyze the development of research on soil organic carbon (SOC) and its current status from various perspectives, with the goal of revealing research hotspots and trends of SOC. A total of 3909 studies published between 2014 and 2023 were included in the analysis. Results show that China and the USA lead with a significant number of publications on SOC, which underscores their considerable interest in the subject. France and the USA exhibit a very high international influence in this field, with their intermediary centrality reaching up to 0.3 and 0.21, respectively. Among institutions, the Chinese Academy of Sciences is the largest contributor in terms of the number of publications, with a high centrality of 0.09, indicating this institution has built close collaboration and significant influence in this field. Kuzyakov Yakov achieved the highest publication record, with Lal Rattan sharing the second position. The hotspots in SOC can be summarized into the following aspects: conservation tillage, carbon sequestration, microbial biomass, and driving forces. The research focus has gradually shifted from macroscopic trends to explanations based on micro-level biological dynamics. Driving forces such as soil type, land use, and environmental conditions have a significant impact on the quantity, turnover, and spatiotemporal distribution of SOC. We highlighted that more attention should be paid to the mechanism of SOC transformation and stabilization, which is essential for developing more precise models of carbon cycling in the soil and for formulating effective strategies to maintain sustainable agriculture and mitigate climate change.

Characteristics and Drivers of Soil Carbon, Nitrogen, and Phosphorus Ecological Stoichiometry at the Heavy Degradation Stage of the Alpine Meadow

An in-depth understanding of the soil nutrient status and balance relationship can help the effective recovery and management of alpine degraded meadows. In order to study the balance relationship among soil carbon, nitrogen, and phosphorus nutrients during the heavy degradation stage of meadows, field sampling and investigation, indoor analysis, and mathematical statistics were used to explore the characteristics and driving factors of changes in soil carbon, nitrogen, and phosphorus content, storage, and ecological stoichiometry during the heavy degradation stage of alpine meadows in the Sanjiangyuan region. The results showed that in the heavy degradation stage, miscellaneous grass plants occupied absolute dominance, soil C∶N∶P was approximately 32.83∶3.87∶0.67, and there was certain nitrogen limitation. The coefficients of variation of soil carbon, nitrogen, and phosphorus content were in the following order： organic carbon （1.09） > total nitrogen （0.63） > total phosphorus （0.29）. The organic carbon content and the carbon and nitrogen ratio showed a significant linear decreasing trend with the increase in the grassland degradation index （GDI）, while the total phosphorus content and organic carbon storage showed a significant non-linear change, in which the total phosphorus content showed a significant gentle U-shaped distribution, and the organic carbon storage decreased more gently at the beginning of the heavy degradation stage and then decreased sharply when the GDI was 57.9. The results of Mantel correlation analysis showed that the soil carbon to nitrogen ratio, carbon to phosphorus ratio, and nitrogen to phosphorus ratio showed significant correlation with organic carbon content and storage and total nitrogen storage. The results of structural equation modeling indicated that soil water content had direct effects as well as indirect through vegetation factors, soil carbon, nitrogen, and phosphorus ecological stoichiometry ratios, and soil water content and vegetation factors （height, cover, and biomass） were key environmental factors affecting soil ecological stoichiometry. The research results can provide scientific basis and practical guidance for the restoration of heavily degraded grassland in alpine meadows.

69 The Holos model for estimating greenhouse gases and soil carbon: Characterizing regionalized beef farm model systems

Abstract The objective of this work is to characterize regionally representative beef farm systems that represent dominant or typical surveyed management practices for 11 beef-producing regions across Canada. This work fulfills two further purposes 1) to improve and expand the Holos model interface; and 2) to facilitate the estimation of greenhouse gas (GHG) emissions and soil carbon (C) changes on beef farms in different regions of Canada. Holos version 4 is the whole-farm model of Agriculture and Agri-Food Canada’s to estimate GHG emissions and changes in soil C on Canadian farms in response to shifts in management practices. Holos can be implemented in all 10 Canadian provinces and accounts for GHG emissions from crop and livestock production [enteric and manure methane (CH4), manure and soil N2O emissions], farm machines and infrastructure [on-farm energy carbon dioxide (CO2) emissions], as well as from the upstream production of some farm inputs (synthetic fertilizer and pesticides). The model is designed to utilize data readily available on the farm to answer, ‘What if?’ scenarios, whereby the user can test the effect of changing management practices on their whole-farm GHG budget. To reduce the data input burden on the user, Holos V4 has built-in model livestock systems for beef, dairy, swine and poultry production that characterize the dominant features of these operations in Canada at the national scale based on relevant literature/data and expert opinion. Regarding beef production, we have characterized regionally specific model beef farms for incorporation into Holos, one for each of 11 Canadian beef-producing regions. General characteristics and management practices for each farm were based on the 2011 Beef Farm Survey (Sheppard et al., 2015), which summarizes management information from 1,009 Canadian beef farms, combined with data from the Canadian Cow-Calf Cost of Production Network (Canfax 2023). Each regional farm includes cow-calf, backgrounding in confinement, backgrounding on pasture and finishing components, and considers all the specific feed (e.g., forage, grains, by-products) required for each stage of the beef cycle. These 11 model farms are simulated within the current Holos V4 model to explore the impacts of variation in beef management practices on farm GHG emissions across Canada and on soil C stocks on lands used to produce feed and graze cattle. An overview of the national-level dairy, swine and poultry components in Holos will be presented along with a more detailed perspective of whole-farm GHG budget and multi-decadal soil C dynamics in regionalized beef farms. The impact of management and environmental factors that lead to differences in GHG emissions and soil C stocks in beef farms will also be explored.

Rethinking environmental sustainability in rainfed cropping systems

Rethinking environmental sustainability in rainfed cropping systems

Pile burns as a proxy for high severity wildfire impacts on soil microbiomes

Pile burns as a proxy for high severity wildfire impacts on soil microbiomes

Carbon savings from sugarcane straw-derived bioenergy: Insights from a life cycle perspective including soil carbon changes

Carbon savings from sugarcane straw-derived bioenergy: Insights from a life cycle perspective including soil carbon changes

Deep soil organic carbon: A review

Abstract Soil organic carbon (SOC) sequestration promotes several ecological, economic, and social co-benefits. However, most SOC studies rely on topsoil evaluations (0–30 cm), disregarding a significant fraction of the SOC that is stored in deep layers. Understanding the relationship between deep soil carbon and climate change is imperative in guiding sustainable land management practices, informing climate change mitigation strategies, and preserving the crucial role of deep soil carbon in regulating atmospheric CO 2 levels. We conducted a comprehensive literature review to discuss the origins of deep soil carbon, the globally standardized methodology recommended for measuring SOC stocks, the mechanisms controlling SOC sequestration (physical, chemical, and biochemical) in deep layers, the significance of microbial community in deep soil layers, advancements in radiocarbon studies, the impact of management practices on deep SOC, and the influence of climate change on deep SOC stocks. Overall, more empirical data and long-term studies are needed to address the knowledge gaps in terms of deep SOC and advance our understanding of the role of deep soil carbon in shaping global carbon cycles and climate resilience. The main challenges for accurate SOC estimations and global carbon budgets are the high spatial variability, the relative lack of deep soil measurements, and the need for reliable reference data for modeling improvements. A practical and accurate soil bulk density (BD) estimation in deep layers (i.e., 30–100 cm) is crucial to improve the accuracy of global C stock estimations and should be addressed in further studies. Modeling approaches based on sensors and machine learning techniques are promising tools to overcome this challenge. However, there is still a large variability in methods to measure and report soil BD and SOC stocks worldwide, preventing further advances.

Scalable solution for agricultural soil organic carbon measurements using laser-induced breakdown spectroscopy

Effective verification of soil organic carbon (SOC) improvement interventions through soil carbon sequestration (SCS) requires robust methodologies to measure, report, and verify changes in soil carbon (C) levels. Furthermore, soil C must be monitored over time to ensure that sequestered C is not being re-emitted, thus ensuring the permanence of C removals. The traditional methods for soil C measurement are time-consuming, labor-intensive, and energy-intensive, increasing analysis costs. In this article, we verify the use of a commercially available laser-induced breakdown spectroscopy analyzer, the LaserAg-Quantum, coupled with the recursive feature addition, the gradient-boosted decision trees regression model, and the novelty detection model to predict C in soils. The developed method shows promising performance with an average limit of quantification of 0.75% of C and a precision of 4.10%. Accuracy metrics, including R2, mean absolute error, and root mean square error, yielded values of 0.81, 0.27%, and 0.37% for the validation dataset. Additionally, around 10% of validation samples after the novelty detection model exhibited relative error greater than 30%. Finally, our findings demonstrate the potential of the LaserAg-Quantum process to support measuring SOC in agricultural soils on a large scale.

Changes in Soil Carbon and Nitrogen Along a 3‐m Vertical Profile and Environmental Regulation in Alpine Grassland on the Tibetan Plateau

AbstractMuch attention has been given to the distribution of soil organic carbon and nitrogen in alpine grasslands, but the important role of the deep soil layers has been understudied. In this study, the soil organic carbon and nitrogen contents in the shallow (0–30 cm), middle (30–100 cm) and deep (100–300 cm) layers were examined, and the effects of climatic, soil and vegetation factors were investigated along a climatic gradient on the Tibetan Plateau. We found that although soil organic carbon and nitrogen on the Tibetan Plateau declined logarithmically with depth, the total soil organic carbon and nitrogen in the middle and deep layers accounted for more than two‐thirds of the total carbon and nitrogen in the 3‐m depth soil profile. Carbon to nitrogen ratio increased with soil depth in 1 m soil, but it remained consistent in 1–3 m soil. The surface carbon and nitrogen contents were positively correlated with precipitation. The comprehensive research has revealed that soil carbon and nitrogen contents are mainly influenced by the local humid climate, vegetation productivity, and soil properties, which strongly depend on soil depth. Therefore, more attention should be given to the changes in carbon and nitrogen in deep soils in alpine regions.

A Bayesian approach to analyzing long-term agricultural experiments

A Bayesian approach to analyzing long-term agricultural experiments

Decadal change in soil carbon and nitrogen with a Miscanthus × giganteus crop on abandoned agricultural land in southeast Ohio

AbstractMiscanthus × giganteus (miscanthus) is considered a beneficial biomass energy crop because of its carbon (C) sequestration potential and low fertilizer requirements, but few studies in the United States have measured long‐term C sequestration of miscanthus on suboptimal agricultural lands over a decadal scale, and none have been conducted in southeast Ohio. The objective of this study was to measure the soil C sequestration on abandoned agricultural land with a miscanthus crop that is harvested annually, the long‐term changes in plant and soil nitrogen (N), and the photosynthetic capacity in the tenth year of growth. This study was conducted over a 10‐year period from 2013 through 2023. A significant amount of C was accumulated in the soil (p < 0.05) and the mean C sequestration rates were 0.83 and 1.37 Mg C ha−1 year−1 at two different sites. The amount of C accumulated in the miscanthus plots by the tenth year was also greater than soil C in unmanaged grassland soils, but the difference was not statistically significant (p > 0.05). There was no statistically significant change in the amount of N found in soil and plants over 10 years (p > 0.05), but the variability in plant N was greater in some years relative to others. Even though miscanthus was grown without N fertilizers in this study, soil N at 0–30 cm depth was not depleted over 10 years of crop management. The photosynthetic capacity of miscanthus measured in this study indicated that the plants were thriving after 10 years, and C assimilation for growth was consistent with the findings of prior work that evaluated the maximum photosynthetic rates of this species. The combination of significant soil C sequestration, sustained soil N, and high photosynthetic rates has important implications for the sustainability of miscanthus as a biomass crop.

Changes of soil carbon along precipitation gradients in three typical vegetation types in the Alxa desert region, China

The changes and influencing factors of soil inorganic carbon (SIC) and organic carbon (SOC) on precipitation gradients are crucial for predicting and evaluating carbon storage changes at the regional scale. However, people’s understanding of the distribution characteristics of SOC and SIC reserves on regional precipitation gradients is insufficient, and the main environmental variables that affect SOC and SIC changes are also not well understood. Therefore, this study focuses on the Alxa region and selects five regions covered by three typical desert vegetation types, Zygophyllum xanthoxylon (ZX), Nitraria tangutorum (NT), and Reaumuria songarica (RS), along the climate transect where precipitation gradually increases. The study analyzes and discusses the variation characteristics of SOC and SIC under different vegetation and precipitation conditions. The results indicate that both SOC and SIC increase with the increase of precipitation, and the increase in SOC is greater with the increase of precipitation. The average SOC content in the 0–300cm profile is NT (4.13 g kg−1) > RS (3.61 g kg−1) > ZX (3.57 g kg−1); The average value of SIC content is: RS (5.78 g kg−1) > NT (5.11 g kg−1) > ZX (5.02 g kg−1). Overall, the multi-annual average precipitation (MAP) in the Alxa region is the most important environmental factor affecting SIC and SOC.

Macrogenomics reveal the effects of inter-cropping perilla on kiwifruit: impact on inter-root soil microbiota and gene expression of carbon, nitrogen, and phosphorus cycles in kiwifruit.

Intercropping systems can improve soil fertility and health, however, soil microbial communities and functional genes related to carbon, nitrogen and phosphorus cycling under the intercropping system of mesquite and perilla have not been studied. Therefore, in the present study, different planting densities and varieties of Perilla frutescens (L.) Britt and kiwifruit were used for intercropping, and changes in soil microbial communities and carbon, nitrogen, and phosphorus cycling genes in kiwifruit inter-roots under inter-cropping conditions were investigated by macro-genome sequencing technology. The results showed that intercropping with Perill caused a decrease in most soil nutrients, soil enzyme activities, and had a significant impact on the microbial (bacteria and fungi) diversity. Inter-cropping increased the relative abundance of the dominant bacterial phylum "Proteobacteria" and "Actinobacteria" by 47 and 57%, respectively, but decreased the relative abundance of the dominant fungal phylum "Chordata" and "Streptophyta" by 11 and 20%, respectively, in the inter-root soil of kiwifruit, and had a significant impact on the microbial (bacteria and fungi) diversity. In addition, inter-cropping could greatly increase the inter-root soil carbon sequestration (PccA, korA/B/C/D, fhs, and rbcl/s), carbon degradation (abfD), organic nitrogen mineralization (GDH2), denitrification (napA/B, nirB, norB), organic phosphorus mineralization (phop, phn), and inorganic phosphorus solubilization (gcd, ppk) gene abundance. The gene co-occurrence network indicated that soil korB, nirB, and gnd key functional genes for carbon, nitrogen, and phosphorus cycling in kiwifruit inter-root soils and their expression was up-regulated in the inter-cropping group. Structural equation (SEM) further showed that soil total nitrogen, organic matter, total carbon and acid phosphatase had significant effects on microbial diversity (p < 0.05) and soil carbon cycling gene korB and phosphorus cycling gene purH (p < 0.001), while korB and purH had positive effects on kiwifruit quality. In conclusion, intercropping perilla in kiwifruit orchards changed the structure of bacterial and fungal communities in the inter-root soil of kiwifruit, but I believe that intercropping perilla stimulates carbon degradation, leading to carbon emission and serious loss of soil nutrients, and that prolonged intercropping may adversely affect the quality of kiwifruit, and thus its limitations should be noted in future studies.

Environmental correlates of the forest carbon distribution in the Central Himalayas.

Understanding the biophysical limitations on forest carbon across diverse ecological regions is crucial for accurately assessing and managing forest carbon stocks. This study investigates the role of climate and disturbance on the spatial variation of two key forest carbon pools: aboveground carbon (AGC) and soil organic carbon (SOC). Using plot-level carbon pool estimates from Nepal's national forest inventory and structural equation modelling, we explore the relationship of forest carbon stocks to broad-scale climatic water and energy availability and fine-scale terrain and disturbance. The forest AGC and SOC models explained 25% and 59% of the observed spatial variation in forest AGC and SOC, respectively. Among the evaluated variables, disturbance exhibited the strongest negative correlation with AGC, while the availability of climatic energy demonstrated the strongest negative correlation with SOC. Disturbances such as selective logging and firewood collection result in immediate forest carbon loss, while soil carbon changes take longer to respond. The lower decomposition rates in the high-elevation region, due to lower temperatures, preserve organic matter and contribute to the high SOC stocks observed there. These results highlight the critical role of climate and disturbance regimes in shaping landscape patterns of forest carbon stocks. Understanding the underlying drivers of these patterns is crucial for forest carbon management and conservation across diverse ecological zones including the Central Himalayas.