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Purpose: Accurately assessing soil organic carbon (SOC) content is vital for ecosystem services management and addressing global climate challenges. This study undertakes a comprehensive bibliometric analysis of global estimates for SOC using remote sensing (RS) and machine learning (ML) techniques. It showcases the historical growth and thematic evolution in SOC research, aiming to amplify the understanding of SOC estimation themes and provide scientific support for climate change adaptation and mitigation. Materials and Methods: Employing extensive literature database analysis, bibliometric network analysis, and clustering techniques, the study reviews 1,761 articles on SOC estimation using RS technologies and 490 articles on SOC employing both RS and ML technologies. Results and Discussion: The results indicate that satellite-based RS, particularly the Landsat series, is predominant for estimation of SOC and other associated studies, with North America, China, and Europe leading in evaluations with Africa is having low evaluations adopting RS technology. Trends in the research demonstrate an evolution from basic mapping to advanced topics such as carbon (C) sequestration, complex modeling, and big data utilization. Thematic clusters from co-occurrence analysis suggest the interplay between technology development, environmental surveys, soil properties, and climate dynamics. Conclusion: The study highlights the synergy between RS and ML, with advanced ML techniques proving to be critical for accurate SOC estimation. These findings are crucial for comprehensive ecosystem SOC estimation, informed environmental management and strategic decision-making. [ABSTRACT FROM AUTHOR]

This paper explores the application and advantages of remote sensing, machine learning, and mid-infrared spectroscopy (MIR) as a popular proximal sensing spectroscopy tool in the estimation of soil organic carbon (SOC). It underscores the practical implications and benefits of the integrated approach combining machine learning, remote sensing, and proximal sensing for SOC estimation and prediction across a range of applications, including comprehensive soil health mapping and carbon credit assessment. These advanced technologies offer a promising pathway, reducing costs and resource utilization while improving the precision of SOC estimation. We conducted a comparative analysis between MIR-predicted SOC values and laboratory-measured SOC values using 36 soil samples. The results demonstrate a strong fit (R² = 0.83), underscoring the potential of this integrated approach. While acknowledging that our analysis is based on a limited sample size, these initial findings offer promise and serve as a foundation for future research. We will be providing updates when we obtain more data. Furthermore, this paper explores the potential for commercialising these technologies in Australia, with the aim of helping farmers harness the advantages of carbon markets. Based on our study's findings, coupled with insights from the existing literature, we suggest that adopting this integrated SOC measurement approach could significantly benefit local economies, enhance farmers' ability to monitor changes in soil health, and promote sustainable agricultural practices. These outcomes align with global climate change mitigation efforts. Furthermore, our study's approach, supported by other research, offers a potential template for regions worldwide seeking similar solutions. [ABSTRACT FROM AUTHOR]

• Climate Resilient Trajectories consider aspects of climate change adaptation and mitigation in a sustainability context. • Specific and complex contexts in which poor and marginalized people operate need to be considered. • Critical to consider short- and long-term time frames when prioritizing and implementing development agendas for the poor. • Involvement of relevant stakeholders key to ensuring trajectories yield expected benefits. Climate Resilient Trajectories are routes to development progress that take into account aspects of climate change adaptation and mitigation in a sustainability context, offering a way to explicitly consider impacts of development and climate change choices on different sectors, scales, and socio-economic effects. Due to their scope and relevance, Climate Resilient Trajectories are of great interest to climate scientists, governments and the private sector, based on the urgent need to consider different strategies to decarbonize the economy. Pursuing such trajectories may also be beneficial in processes to implement the UN Sustainable Development Goals (SDGs) up to 2030 and beyond. This Communication describes the concept of Climate Resilient Trajectories and clarifies its relevance, with particular attention to the poor. It also outlines some of the necessary considerations to ensure no one is left behind. It highlights the need for the design of Climate Resilient Trajectories to be flexible enough to accommodate the specific and complex contexts in which poor and marginalized people operate; and that the involvement of all relevant stakeholders (e.g. governments, business and private organizations, policy makers, and whole communities) is necessary in order to ensure such trajectories yield the expected benefits. It further demonstrates that it is critical to consider both short- and long-term time frames when prioritizing and implementing development agendas for the poor. [ABSTRACT FROM AUTHOR]

The climatic and non-climatic stresses impacted adversely to the functioning and productivity of the forests, resulting in disturbing the existing carbon flow in the atmosphere. Cedrus deodara occurs in pure forest stands throughout the Western Himalayas and has high biomass and soil carbon sequestration potential. The present study aims to provide the contribution of the Cedrus deodara forests under the current stresses for climate mitigation by analysing the three elevation ranges of the Dhanaulti forest division of Garhwal Himalaya, India. The results report that soil organic carbon (SOC) was adversely and bulk density favourably related with elevation. Moreover, SOC as CO2eq also decreased significantly with an increase in soil depths. Biomass carbon for various parts of the plant was also estimated for the three elevations of the Cedrus deodara forests. The trend in total carbon stock (bole, branch, twig, foliage and soil) decreased significantly with an increase in altitude. The carbon stock of Cedrus deodara forests was maximum (545 t ha−1) at upper altitude (2350 m.a.s.l) and minimum (330 t ha−1) at a lower altitude (2050 m.a.s.l). The difference in litter production between the seasons is significant with maximum production in summer followed by rainy and winter seasons. This study provides inputs for greenhouse gas (GHG) estimation for national communication to various platforms. The information on the soil is crucial for understanding about the ecology of the forests assisting prediction of functioning and productivity of forests. [ABSTRACT FROM AUTHOR]

• Nature-based Solutions (NbS) in Himalayas has sustainable management and restoration of resources. • Most of the NbS of Himalaya adheres the IUCN standard criteria. • Improved NbS interventions in Himalaya requires precise planning and engaging multiple stakeholders. Himalayan countries face many ecological challenges, including biodiversity loss and the many threats of climate change. In response, these countries are implementing Nature-based Solution to minimize these challenges and promote sustainable development. In this article we analyze the NbS programs implemented across the Himalayan region and assess the limitations of these NbS using the IUCN standard criteria of adherence to NbS for selected articles. We perform a systematic review of articles using the PRISMA methodology, through the Scopus, Google Scholar, and ResearchGate databases and followed by screening through the Rayyan web interface. Articles were screened out based on the location and lack of biodiversity and human well-being outcomes of NbS intervention. Nature-based Solutions in the Himalayas primarily use a sustainable management approach (35.29%), followed by restoration (23.53%), conservation (11.76%), holistic management (11.76%), eco-DRR (11.76%) and green infrastructure (5.88%) to address societal and climatic challenges. Institutional execution of NbS was 29.41% more common compared to the implementation of NbS by community or farmer groups. Pineapple based agroforestry (83.04%), forest restoration (78.57%), spring water storage (83.04%), spring restoration (86.61%), groundwater recharge (82.14%), bio-fertilizer and pesticides (77.68%), watershed restoration (78.57%), community-based watershed management (77.68%), community-based DRR (81.25%), community-based forest management (81.25%), sustainable harvest of medicinal plants (77.68%) and wetland restoration (82.14%), adhere to the IUCN criteria. In addition, some interventions adequately meet IUCN criteria, such as ice stupas (72.32%), forest restoration through plantation (73.21%), eco-safe roads (65.18), blue-green infrastructure (68.75%), and traditional ecological knowledge (72.32%). Our evaluation noted that NbS interventions can be improved by precise planning and design before implementation, engaging multiple stakeholders, comparing alternative solutions, and periodic monitoring of the impacts on the environment and society. This study shows that NbS in the Himalayas are contributing to biodiversity conservation and climate risk management. Tackling the limitation of this present review, mainly the exclusion of research not addressing biodiversity and human well-being, will yield more precise outcomes for climate actions and sustainable development. [ABSTRACT FROM AUTHOR]

Climate change is predicted to have severe impacts on mountainous regions, including urban settlements, and livelihoods of the urban poor. Adaptive capacity for marginalized groups is largely determined by household-level resources and decision-making capacity. This study investigated the vulnerability status and prevalent adaptation strategies of urban slum dwellers in Dehradun, Indian Himalayas, using a pre-tested questionnaire covering household characteristics and indicators of vulnerability, in face-to-face interviews with the head of 122 randomly selected households in four slums. We found that overall vulnerability was very high, with very low absorptive and coping capacity for potential impacts of climate change. Moreover, vulnerability and coping strategies were socially differentiated in terms of the decision-making capability and resource capacity of households. Two groups per category (good and bad decision makers; poor and poorer households) were distinguished. The exposure dimension of vulnerability differed significantly by resource capacity and decision capability. However, the sensitivity dimension of vulnerability did not differ between the groups, while the adaptive capacity dimension of vulnerability differed depending on decision-making capability. In designing appropriate strategies for long-term disaster mitigation for urban slums, it is thus important to address slum socio-ecology and the capability and capacity of slum dwellers. [ABSTRACT FROM AUTHOR]

The agrarian society of the Himalayan landscape is experiencing the continuous growing ill impact of climate change. The impacts are compounding due to shifting agriculture, which has jeopardized the ecological balance mainly by reducing the cultivation fallow cycles. Pnar, a hill tribe of the Assam state, Indian sub-Himalayan region, has transitioned shifting agriculture to Piper agroforestry (Piper betle L.), providing them numerous tangible and non-tangible benefits. Over the past three decades, there has been a notable transition from shifting agriculture to Piper agroforestry, driven by the rising demand in the market. Understanding climate change impact on agroforestry is crucial to addressing the climate crisis and to provision the adaptation of the tribe for the successful promotion of Piper agroforestry. To assess the cause and nature of vulnerability in the study region, we surveyed 171 randomly selected households across 15 randomly selected tribe villages using the household-level questionnaire. The present study showed that the villages with lower land holdings, higher loss of crop productivity due to extreme events, disease infestation and lower livelihood diversification were more vulnerable to climate change. The prominent diseases "leaf spot" and "root rot" were identified as a serious concern among the Piper farmers responsible for a decline in crop yield; the severity of losses in productivity leads to economic instability among households. Villages with prominent farm management strategies and greater decision-making abilities contributed explicitly to lower vulnerability. In contrast, villages with lower adaptive strategies were found specifically due to poor social networking and inadequate household infrastructure besides poor literacy levels. Additionally, the lack of multi-cropping farming and livestock management was a major cause of high climate sensitivity. Therefore, appropriate state government support is required to invest in crop diversification, better decision-making capability of tribes through education, and improved infrastructure besides diversifying the rural economy to enhance the adaptive capacity of the farmers to reduce their climate vulnerability and achieve agriculture-livestock-forestry nexus. The sustainable Piper agroforestry farm management practices represent climate-smart agriculture, favouring high tree species diversity while reducing the farmers' vulnerability to climate change. [Display omitted] • Assessing the climate vulnerability of Piper agroforestry farmers is vital for climate action and underlying adaptive strategies. • We followed the IPCC framework for climate vulnerability assessment. • Villages, namely Nagathal and Munchicherra, show greater sensitivity; Aulicherra and Dholaikhal exhibit higher climate adaptability. • Disease outbreaks in Piper agroforestry pose risks, causing economic disparities. • Piper agroforestry can be considered a nature-based solution for land restoration, economic crisis management, and environmental benefits. [ABSTRACT FROM AUTHOR]

• Most of the NbS of Tropical drylands of India are not follow the IUCN standard criteria. • The Identified NbS are baised towards environmental services than addressing social needs of the people. • Improved NbS interventions requires intensive enagement of stakeholders for addressing social causes. Nature-based Solutions (NbS) is a flexible, adaptable, and multi-functional strategies employed to address climate change. However, all the claimed NbS are actually do not adhere the criteria of being NbS. Therefore, present study analysed 87 articles to appraise adherence of potential NbS as per the IUCN Global Standard, along with evaluation of flow of associated ecosystem services (ES). The review identified 39 interventions, out of which only twelve interventions adhered the criteria of NbS. Among the classified NbS, two interventions, namely, sustainable forest management (SFM) (80.83%) and haveli rejuvenation (75.61%) strongly adhered to the IUCN Standard. Lack of adherence in the non-classified NbS interventions was mainly attributed to absence of information on inclusive governance, monitoring and associated trade-offs. The identified 39 interventions were also observed to be enhancing a total of 37 ES, evaluated through 37 distinct indicators i.e. different and enhanced flow of ES were observed by the different NbS. However, the majority of classified NbS were biased towards flow of environmental services than social services. Present study results that all claimed NbS cannot fulfilled the intended objectives of NbS and thus cannot be classified under the NbS as per global standard. Moreover, assessing the flow of associated ES may be an additional support to broaden the scope of NbS implementation. Therefore, present study also highlights to integrate the flow of ES along with the adherence criteria of NbS. Moreover, the review also facilitate to understand constraints associated with the implementation of potential NbS interventions and thus, suggests considering wider aspects in the future researches for assessing the implementation of NbS. [ABSTRACT FROM AUTHOR]

• Multi-hazard risk was evaluated for 109 districts of Indian Himalayan Region (IHR). • A Mountain Specific Risk Management Framework (MSMRMF) was proposed. • The MSMRMF consists two components i.e. risk assessment and risk addressal. • The framework deals risk management strategies for multi-hazard prone mountains. Mountains are characterized by their specificities such as fragility, marginality and remoteness. They are prone to various hazards such as drought, flood, forest fire, landslide and therefore physical, ecological and social systems of the mountains are at risk. Climate change adds to intensifying the magnitude of multi-hazard risk in mountains. The present study attempts to evaluate risk induced by multi-hazard and climate change in the Indian Himalayan Region (IHR) using the Intergovernmental Panel on Climate Change (IPCC) framework. The proposed multi-hazard risk index was based on indicators from a broader domain and applied on 109 administrative districts of IHR. Exposure, sensitivity, adaptive capacity, and coping capacity were defined using comprehensive and sub-regional indicators identified through inductive and deductive approaches. The result showed that the differential risks among the districts of IHR were governed by the multiplicity of the factor such as demography, amenities, natural capital, partnership, technology and spatial specificities of the districts. The result highlighted the need of inclusion of spatial specificities for the risk mitigation in the IHR and therefore a Mountain Specific Risk Management Framework (MSMRMF) was proposed for sustaining the mountainous communities. The proposed MSMRMF contained two broad components as risk assessment and risk addressal. The framework detailed the risk mitigation and coping strategies (based on adjustment of internal and external strengths) for addressing risks. Risk mitigation was proposed to achieved through habitation resilience, natural capital enhancement, external partnerships, climate change adaptation, and technological interventions. The framework would provide an insight of risk and risk management strategies for the multi-hazard prone mountain regions for the sustainable development under the global change. [ABSTRACT FROM AUTHOR]

• Leaf C, N, P, and leaf N/P ratio were the main contributors to above-ground biomass. • Leaf N, P, and leaf N/P were the contributors to below-ground processes. • Soil properties explained 60% variation in aboveground biomass. Plant-soil interactions are a major determinant of changes in forest ecosystem processes and functioning. We conducted a trait-based study to quantify the contribution of plant traits and soil properties to above- and below-ground ecosystem properties in temperate forest in the Indian Himalayas. Nine plant traits (leaf area, specific leaf area, leaf water content, leaf dry matter content, leaf carbon (C), nitrogen (N), phosphorus (P), leaf C/N, and leaf N/P) and eight soil properties (pH, moisture, available N, P, potassium (K), total C, N, P) were selected for determination of their contribution to major ecosystem processes (above-ground biomass C, soil organic C, soil microbial C, soil microbial N, soil microbial P, and soil respiration) in temperate forest. Among the plant traits leaf C, N, P, and leaf N/P ratio proved to be the main contributors to above-ground biomass, explaining 20–27% of variation. Leaf N, P, and leaf N/P were the main contributors to below-ground soil organic C, soil microbial C, soil microbial N, soil microbial P, and soil respiration (explaining 33% of variation). Together, the soil properties, pH, available P, total N and C explained 60% of variation in above-ground biomass, while pH and total C explained 56% of variation in soil organic C. Other soil properties (available P, total C and N) also explained much of the variation in soil microbial C (52%) and soil microbial N (67%), while soil pH explained some of variation in soil microbial N (14%). Available P, total N, and pH explained soil microbial P (81%), while soil respiration was only explained by soil total C (70%). Thus, leaf traits and soil characteristics significantly explaining variations in above- and below-ground ecosystem processes and functioning in temperate forest in the Indian Himalayas. Consequently, tree species for afforestation, restoration, and commercial forestry should be carefully selected, as they can influence the climate change mitigation potential of forest in terms of C stocks in biomass and soils. [ABSTRACT FROM AUTHOR]

• Productivity parameters of Cedrus deodara forests decreases with altitude. • Biomass and soil carbon of Cedrus deodara forests decreases with altitude. • Litterfall production also decreased with altitude. Carbon inventories are urgently needed for understanding climate dynamics and implementing climate mitigation strategies, but such data is scarce in for forest ecosystem of Himalaya. Therefore, the present study focuses to supplement the existing information by estimating carbon stocks in temperate forests dominated by Cedrus deodara along the altitudinal gradients in the Central Himalaya. Three altitudes i.e., lower (1750 m), middle (1900 m) and upper (2050 m) of the stand was considered to understand and estimate biomass and soil carbon storage potential of the forests based on the standard protocol. The results showed that the soil carbon stock (SOC) decreased significantly with increasing soil depths and altitudes. Litterfall production in the forests varied adversely with altitude. Above and below-ground biomass carbon stock also decreased along with altitude. The study observed that the total carbon stock (soil, trees and forest floor) of the Cedrus deodara forest in different altitudes was 395.4 t ha−1 (lower altitude), 321.6 t ha−1 (middle altitude) and 282.5 t ha−1 (upper altitude). The estimates of the Cedrus forests would provide guidelines for estimating carbon for forest-based mitigation activities in the Himalayan region. [ABSTRACT FROM AUTHOR]