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In approximately one decade, global temperatures will likely exceed a warming level that a United Nations Intergovernmental Panel on Climate Change report considers a "red alert for humanity". We propose exploring tidal flat diatoms to address climate change challenges. Tidal flats are extensive coastal ecosystems crucial to the provisioning and regulation of aquatic environments. Diatoms contribute to tidal flat biomass production and account for 20% of global primary productivity and 40% of annual marine biomass production, making them crucial for nutrient cycling and sediment stabilization. Potential CO2 removal from Korean tidal flats by diatoms is estimated to be 598,457–683,171 t CO2 equivalents (CO2e) annually, with the economic value of blue carbon (BC) resulting from diatom activity being approximately US$ 17.95–20.50 million. Dissemination of this potential could incentivize coastal wetland protection and climate change mitigation measures. The global estimated CO2e removal potential of tidal flat diatoms is 40,957,346–46,754,961 t CO2e, representing 0.11–0.13% of the annual global greenhouse gas emissions, even though tidal flats cover 0.0025% of the Earth's surface and diatoms represent less than 0.5% (by weight) of all photosynthetic plants. Researchers should combine ecology and economics to develop standardized approaches for carbon input monitoring and quantification. Further, spatiotemporal analyses of environmental threats to tidal flat diatoms are necessary for conserving their biodiversity and function as a critical BC source. Land-based cultivation for large-scale biomass production and biorefinery processes can contribute to a greener, more prosperous future for humanity and the marine ecosystems upon which we rely. [ABSTRACT FROM AUTHOR]

The term carbon (C) sequestration has not just become a buzzword but is something of a siren's call to scientific communicators and media outlets. Carbon sequestration is the removal of C from the atmosphere and the storage, for example, in soil. It has the potential to partially compensate for anthropogenic greenhouse gas emissions and is, therefore, an important piece in the global climate change mitigation puzzle. However, the term C sequestration is often used misleadingly and, while likely unintentional, can lead to the perpetuation of biased conclusions and exaggerated expectations about its contribution to climate change mitigation efforts. Soils have considerable potential to take up C but many are also in a state of continuous loss. In such soils, measures to build up soil C may only lead to a reduction in C losses (C loss mitigation) rather than result in real C sequestration and negative emissions. In an examination of 100 recent peer‐reviewed papers on topics surrounding soil C, only 4% were found to have used the term C sequestration correctly. Furthermore, 13% of the papers equated C sequestration with C stocks. The review, further, revealed that measures leading to C sequestration will not always result in climate change mitigation when non‐CO2 greenhouse gases and leakage are taken into consideration. This paper highlights potential pitfalls when using the term C sequestration incorrectly and calls for accurate usage of this term going forward. Revised and new terms are suggested to distinguish clearly between C sequestration in soils, SOC loss mitigation, negative emissions, climate change mitigation, SOC storage, and SOC accrual to avoid miscommunication among scientists and stakeholder groups in future. [ABSTRACT FROM AUTHOR]

Most of the world's nations (around 130) have committed to reaching net‐zero carbon dioxide or greenhouse gas (GHG) emissions by 2050, yet robust policies rarely underpin these ambitions. To investigate whether existing and expected national policies will allow Brazil to meet its net‐zero GHG emissions pledge by 2050, we applied a detailed regional integrated assessment modelling approach. This included quantifying the role of nature‐based solutions, such as the protection and restoration of ecosystems, and engineered solutions, such as bioenergy with carbon capture and storage. Our results highlight ecosystem protection as the most critical cost‐effective climate mitigation measure for Brazil, whereas relying heavily on costly and not‐mature‐yet engineered solutions will jeopardise Brazil's chances of achieving its net‐zero pledge by mid‐century. We show that the full implementation of Brazil's Forest Code (FC), a key policy for emission reduction in Brazil, would be enough for the country to achieve its short‐term climate targets up to 2030. However, it would reduce the gap to net‐zero GHG emissions by 38% by 2050. The FC, combined with zero legal deforestation and additional large‐scale ecosystem restoration, would reduce this gap by 62% by mid‐century, keeping Brazil on a clear path towards net‐zero GHG emissions by around 2040. While some level of deployment of negative emissions technologies will be needed for Brazil to achieve and sustain its net‐zero pledge, we show that the more mitigation measures from the land‐use sector, the less costly engineered solutions from the energy sector will be required. Our analysis underlines the urgent need for Brazil to go beyond existing policies to help fight climate emergency, to align its short‐ and long‐term climate targets, and to build climate resilience while curbing biodiversity loss. [ABSTRACT FROM AUTHOR]

The article focuses on the importance of establishing a regionally focused and coordinated carbon dioxide removal (CDR) science-policy platform in southern Africa. The topics include the significance of CDR in steering the planet towards a safe climate, the challenges and opportunities associated with CDR interventions, and the need for governance mechanisms, technologies, and scientific capabilities to support CDR development.

Mangroves have been identified as blue carbon ecosystems that are natural carbon sinks. In Bangladesh, the establishment of mangrove plantations for coastal protection has occurred since the 1960s, but the plantations may also be a sustainable pathway to enhance carbon sequestration, which can help Bangladesh meet its greenhouse gas (GHG) emission reduction targets, contributing to climate change mitigation. As a part of its Nationally Determined Contribution (NDC) under the Paris Agreement 2016, Bangladesh is committed to limiting the GHG emissions through the expansion of mangrove plantations, but the level of carbon removal that could be achieved through the establishment of plantations has not yet been estimated. The mean ecosystem carbon stock of 5–42 years aged (average age: 25.5 years) mangrove plantations was 190.1 (±30.3) Mg C ha−1, with ecosystem carbon stocks varying regionally. The biomass carbon stock was 60.3 (±5.6) Mg C ha−1 and the soil carbon stock was 129.8 (±24.8) Mg C ha−1 in the top 1 m of which 43.9 Mg C ha−1 was added to the soil after plantation establishment. Plantations at age 5 to 42 years achieved 52% of the mean ecosystem carbon stock calculated for the reference site (Sundarbans natural mangroves). Since 1966, the 28,000 ha of established plantations to the east of the Sundarbans have accumulated approximately 76,607 Mg C year−1 sequestration in biomass and 37,542 Mg C year−1 sequestration in soils, totaling 114,149 Mg C year−1. Continuation of the current plantation success rate would sequester an additional 664,850 Mg C by 2030, which is 4.4% of Bangladesh's 2030 GHG reduction target from all sectors described in its NDC, however, plantations for climate change mitigation would be most effective 20 years after establishment. Higher levels of investment in mangrove plantations and higher plantation establishment success could contribute up to 2,098,093 Mg C to blue carbon sequestration and climate change mitigation in Bangladesh by 2030. [ABSTRACT FROM AUTHOR]

Agriculture is the second-highest, after energy use, source of greenhouse gas emissions, which are released from soils and animal digestion processes and as a result of energy consumption at various stages of agricultural production. However, changes in the management of agricultural systems may mitigate the negative impact of this sector on the atmosphere and climate. This paper presents a literature review on energy consumption in agriculture and the potential of agricultural crop production to assist in mitigation of global warming by increasing absorption of CO2 from the atmosphere. The issue was considered in the context of managing the cultivation of main, catch and cover crops. The potential of carbon sequestration in the above- and below-ground biomass of selected crops was analyzed. It was stated that, depending on the species, main crops can sequester up to 113 CO2 ha−1 yr−1 in whole biomass, while catch or cover crops can sequester up to 14.80 CO2 ha−1 yr−1 and 0.17 CO2 ha−1 yr−1 in the above- and below-ground biomass, respectively. The benefits of the spread of catch or cover crops, such as improvement of soil quality (leading to an increase in primary crop yield by even as much as 65%) and a phytosanitary effect, as well as the barriers that limit the use of catch crops, including the problems with matching crop species to climate and soil conditions and the risk of reducing farmers' income, were considered. The results of the review show that catch crops can assimilate an additional amount of 4 to 6 tonnes CO2 ha−1 yr−1, and thus, spreading of catch crops is an effective way to reduce the climate impact of agriculture. [ABSTRACT FROM AUTHOR]

Agriculture contributes to global climate change by producing 20–25% of greenhouse gases (GHGs). CO 2 is released from deforestation and land conversion, methane from rice paddy fields, and nitrous oxides from overfertilization. An increasing world population requires a change in the agro food systems, including a reduction in chemical fertilizers and pesticides as well as the production and access to food. Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels. [ABSTRACT FROM AUTHOR]

Ecosystem-based approaches to climate change mitigation involves the use of ecosystems carbon storage and sequestration services. For this purpose, comprehensive CO2 efflux (Reco) measurements of the wetland and terrestrial ecosystems were performed in the adjacent area of Bucharest, by applying two complementary methods using close chambers: dynamic by respiration chamber and static by injection kit. For the evaluation and comparison in time, the measurements were performed simultaneously with the two methods at relevant time intervals. The results of both practices have been inter-compared in the established plots. The aim of this paper is to highlight the values of Reco measured on days when extreme temperatures and precipitations were recorded. The data set from the selected days was statistically analyzed in comparison with the recorded measurements during the corresponding season. The results highlight the response of CO2 efflux in relation with daily meteorological parameters, for analyzing the ecosystems storage and carbon sequestration in the context of climate change. In addition, the analysis performed contributes to the uncertainty reduction for the independent use of the two methods as a monitoring tool for greenhouse gases exchanges between ecosystems and atmosphere. [ABSTRACT FROM AUTHOR]

Rising CO2 emissions call for actions to urgently address climate change and its impacts. To avoid the harmful consequences of climate change, limiting anthropogenic emissions of CO2 are a sensible response recognized by the global scientific community. Carbon capture and storage technologies are an integral part of the climate change mitigation portfolio. Among the various technologies, mineral carbonation shows promising potential as it is safer and offers a permanent solution for carbon capture and storage in the form of solid carbonates. In this regard, direct mineral carbonation of alkaline solid residues is viewed with global interest as they offer permanent and leakage-free storage of CO2. In this research work, CO2 sequestration using Indian coal fly ash (class F type- CaO < 10%) has been studied through the direct mineral carbonation process using flue gas concentration of CO2. Response surface methodology was used to design the carbonation experiments through gas–solid and aqueous routes. Aqueous carbonation of coal fly ash at optimum conditions (temperature-61.6 °C, pressure-48.7 bar, liquid/solid ratio-13.35, reaction time-50 min) resulted in a reduction of about 23% in the concentration of CO2. The waste exhibited a maximum sequestration capacity of 50.72 g of CO2/kg under aqueous carbonation and 20.03 g of CO2/kg under gas–solid carbonation. Both temperature and pressure were found to be significant factors impacting the gas–solid carbonation process. In aqueous carbonation, temperature and liquid/solid ratio were the significant factors. The carbonation process was evidenced using Fourier-transform-infrared spectroscopy, X-ray diffraction, and scanning electron microscope studies. The results suggest that Indian coal fly ash could be considered a potential feedstock for sequestration of CO2 with flue gas and requires further improvement for large-scale implementations. [ABSTRACT FROM AUTHOR]

Mangroves have among the highest carbon densities of any tropical forest. These 'blue carbon' ecosystems can store large amounts of carbon for long periods, and their protection reduces greenhouse gas emissions and supports climate change mitigation. Incorporating mangroves into Nationally Determined Contributions to the Paris Agreement and their valuation on carbon markets requires predicting how the management of different land‐uses can prevent future greenhouse gas emissions and increase CO2 sequestration. We integrated comprehensive global datasets for carbon stocks, mangrove distribution, deforestation rates, and land‐use change drivers into a predictive model of mangrove carbon emissions. We project emissions and foregone soil carbon sequestration potential under 'business as usual' rates of mangrove loss. Emissions from mangrove loss could reach 2391 Tg CO2 eq by the end of the century, or 3392 Tg CO2 eq when considering foregone soil carbon sequestration. The highest emissions were predicted in southeast and south Asia (West Coral Triangle, Sunda Shelf, and the Bay of Bengal) due to conversion to aquaculture or agriculture, followed by the Caribbean (Tropical Northwest Atlantic) due to clearing and erosion, and the Andaman coast (West Myanmar) and north Brazil due to erosion. Together, these six regions accounted for 90% of the total potential CO2 eq future emissions. Mangrove loss has been slowing, and global emissions could be more than halved if reduced loss rates remain in the future. Notably, the location of global emission hotspots was consistent with every dataset used to calculate deforestation rates or with alternative assumptions about carbon storage and emissions. Our results indicate the regions in need of policy actions to address emissions arising from mangrove loss and the drivers that could be managed to prevent them. [ABSTRACT FROM AUTHOR]

In the face of escalating global climate challenges, effective carbon dioxide (CO₂) capture techniques remain at the forefront of mitigating anthropogenic greenhouse gas emissions. This comprehensive review elucidates the latest advancements in CO₂ capture, emphasizing two predominant methodologies: absorption and adsorption. We delve into the mechanisms underlying each process, highlighting the novel materials and technologies that have emerged over recent years. For absorption, the focus is placed on the material design strategy, and identifying new materials in the class of amines, ionic liquids (ILs) and nanofluids for enhanced CO 2 capture capacities and reduced energy requirements. In the realm of adsorption, the synthesis of innovative adsorbents, such as metal organic framework (MOF), organic polymers, inorganic adsorbents, silicon-based adsorbents, and biochar and byproducts from biomass with superior selectivity and stability, is explored. Additionally, the review addresses the challenges associated with each method, offering insights into potential avenues for further research. By providing a holistic overview of the current landscape of CO₂ capture, this article serves as a pivotal resource for researchers and industry professionals aiming to advance sustainable solutions to combat climate change. [Display omitted] • Absorption and adsorption materials are at the forefront of CO 2 capture technologies. • Ionic-liquids and nanofluids can be comparable to amines with improvements in scalability and stability. • Biomass byproducts as adsorbents offers a sustainable solution to CO 2 capture. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is mainly universal greenhouse gas associated with climate change. However, beyond CO2, some other greenhouse gases (GHGs) like methane (CH4) and nitrous oxide (N2O), being two notable gases, contribute to global warming. Since 1900, the concentrations of CO2 and non-CO2 GHG emissions have been elevating, and due to the effects of the previous industrial revolution which is responsible for climate forcing. Globally, emissions of CO2, CH4, and N2O from agricultural sectors are increasing as around 1% annually. Moreover, deforestation also contributes 12–17% of total global GHGs. Perhaps, the average temperature is likely to increase globally, at least 2 °C by 2100—by mid-century. These circumstances are responsible for climate forcing, which is the source of various human health diseases and environmental risks. From agricultural soils, rhizospheric microbial communities have a significant role in the emissions of greenhouse gases. Every year, microbial communities release approximately 1.5–3 billion tons of carbon into the atmospheric environment. Microbial nitrification, denitrification, and respiration are the essential processes that affect the nitrogen cycle in the terrestrial environment. In the twenty-first century, climate change is the major threat faced by human beings. Climate change adversely influences human health to cause numerous diseases due to their direct association with climate change. This review highlights the different anthropogenic GHG emission sources, the response of microbial communities to climate change, climate forcing potential, and mitigation strategies through different agricultural management approaches and microbial communities. [ABSTRACT FROM AUTHOR]

The International Panel on Climate Change (IPCC) recommended more stringent climate mitigation strategies compared to the updated nationally determined contributions (NDC) presented by nations at COP27 to keep global warming temperatures below 2 °C. Given the unique geographical, political, and socioeconomic factors in different regions, it is imperative to evaluate diverse mitigation scenarios required to achieve global climate objectives. This study focuses on the Latin America and Caribbean region due to its vulnerability to global climate adversities and deteriorating climate conditions, notwithstanding its minor contribution to global emissions. Despite facing distinct climate changes, Latin America remains significantly understudied in the broader context of global climate research. The deployment of negative emission technology (NET) is crucial for achieving the end-of-century global climate goal of limiting global mean temperature to 1.5 °C and realizing regional net-zero greenhouse gas (GHG) emission targets. Most countries in Latin America have established such targets for 2050. Among various NETs, Direct Air Carbon Capture and Storage (DACCS) has recently gained research interests. This study examines the strategic implementation of NETs across the five socio-economic pathways (SSPs) to provide a comprehensive understanding of the uncertainties in regional mitigation actions and impacts on the intricate climate-energy-land-food-water nexus. In the scenario where emissions decrease by 56 % by 2030 compared to 2020 levels (NDC-56 %) on a net-zero trajectory, energy consumption under DACCS deployment is 13.1–36.2 % higher than without DACCS (between 2040 and 2100, across all SSPs). The energy demands of DACCS, especially in the aggressive NDC-56 % scenario place significant strain on energy resources, which is offset by fossil fuels. Under a globally co-ordinated climate policy and co-deployment of DACCS and Bioenergy with Carbon Capture and Storage (BECCS), the NDC-56 % scenario restricts global warming temperatures to 1.81–1.96 °C by 2100. • IAM analysis is used in assessing scenarios of net-zero goal of Latin America. • The deployment of DACCS under aggressive decarbonization is analysed. • The deployment of DACCS reduces the demand on BECCS requirements. • DACCS deployment will reach 88 MtCO 2 /year in the NDC-SSP1 scenario by 2100. [ABSTRACT FROM AUTHOR]

G LOBALLY, there is an increased global awareness of some environmental issues such as climate change. In this regard, new accessible and reliable data, locally and globally, regarding soil carbon (C) and nitrogen (N) stocks and their physical and chemical fractions, are needed. These data assist in making suitable decisions towards the mitigation of climate change impacts. Soil acts an important role in the global cycles (i.e. carbon (C) and nitrogen (N) ) and both are linked and related not only to climate change mitigation but also sustaining agricultural productivity and improving soil quality. Soil C and N sequestration. Moreover, using good and novel long-term management practices are the most important methods for increasing their stocks and mitigating greenhouse gases (GHGs) emission, from soil to the atmosphere as well for improving soil quality and increase economic crop production. Therefore, the aim of this review is to summarize some basic information about soil C and N stocks and their fractions, especially they are related to climate change mitigation and soil quality. [ABSTRACT FROM AUTHOR]

Excessive emissions of greenhouse gases, such as carbon dioxide, can cause severe global climatic changes, which may include an increase in the global temperature, rise of the sea level, increase in wildfire, floods, and storms, in addition to changes in the amount of rain and snow. The global mitigation strategies that can be envisioned to reduce the release of greenhouse gas emissions to the atmosphere include retrofitting buildings with more energy-efficient systems, increasing the dependency on renewable energy sources in lieu of fossil fuels, increasing the use of sustainable transportation systems that rely on electricity and biofuels, and adopting globally more sustainable uses of land and forests. To reduce global climatic changes, the excess amount of carbon dioxide in the environment needs to be captured and stored in deep underground sedimentary reservoirs. The sedimentary reservoirs that contain water in the rock matrix provide a more secure CO2 sequestration medium. The injection of carbon dioxide causes a huge increase in the reservoir pore pressure and provokes the subsequent ground uplift. The excessive increase in pore pressure may also cause leakage of carbon dioxide into the potable water layers and to the atmosphere, thus leading to severe global climatic changes. In order to maintain the integrity of the sequestration process, it is crucial to inject a safe quantity of carbon dioxide into the sequestration site. Accordingly, the injection period and the safe values of injection parameters, like flow rate and injection pressure, need to be calculated a priori to ensure that the stored carbon dioxide will not leak into the atmosphere and jeopardize the climate mitigation strategy. To model carbon dioxide injection in reservoirs having a base fluid, such as water, one has to perform a two-phase flow modeling for both the injected and base fluids. In the present investigation, carbon dioxide is injected into Biyadh reservoir, wherein the two-phase flow through the reservoir structure is taken into account. This investigation aims to estimate the safe parameter values for carbon dioxide injection into the Biyadh reservoir, in order to avoid leakage of carbon dioxide through the caprock. In this context, the two cases of a fractured and non-fractured caprock are considered. To ensure a safe sequestration mechanism, the coupled reservoir stability analysis is performed to estimate the safe values of the injection parameters, thus furnishing data for a reliable global climate change mitigation strategy. The obtained results demonstrated that the injection of carbon dioxide has caused a maximum pore pressure increase of 25 MPa and a ground uplift of 35 mm. [ABSTRACT FROM AUTHOR]

Policymakers and businesses in Southeast Asia are increasingly interested in using carbon markets to encourage adoption of regenerative agriculture practices by farmers. These practices are thought to mitigate climate change by reducing soil carbon loss and enhancing soil carbon sequestration. However, there is uncertainty in the ability of regenerative agriculture practices to increase soil organic carbon (SOC) stocks of croplands. We reviewed 92 empirical studies that investigated the effects of 17 regenerative farming practices across 11 broad categories of crops on SOC stock or content in Southeast Asia. Our synthesis found supporting evidence for the use of organic amendments like biochar, compost, and manure, as well as cover cropping, crop rotation, and conservation tillage to increase SOC. However, studies for practices like addition of compost and manure reported increases in greenhouse gas emissions like methane (CH 4) and nitrous oxide (N 2 O), demonstrating that increases in SOC may be offset by increases in greenhouse gas emissions. Only a few studies measured both the changes in SOC stocks and greenhouse gas emissions and none of the studies completed full greenhouse gas inventories. Estimating the net impact of SOC gains and increase of greenhouse gas emissions will be necessary to understand the overall effect of practices like compost, manure and crop residue incorporation on net atmospheric greenhouse gas concentrations. If these practices are implemented for soil carbon projects, practitioners should anticipate increases in greenhouse gas emissions from soils and implement additional practices, such as alternate wetting and drying, to optimize the climate change mitigation effects of regenerative agriculture. We encourage future research on practices, such as agroforestry and changes in crop residue management, where there are few studies and little variation in experimental design and environmental conditions. Given the interest in scaling up regenerative agriculture through voluntary carbon markets to boost SOC stocks in croplands, policymakers and businesses can support research in this area by making field-collected data from their projects accessible to researchers to further the study of the impact of these practices across different abiotic conditions and soil managements. This data sharing would alleviate the paucity and improve the quality of empirical data on regenerative agricultural practices in Southeast Asian croplands, facilitate practice-specific meta-analyses, and help to optimize climate change mitigation effects of regenerative agriculture. • Regenerative agriculture practices can increase soil carbon in Southeast Asia. • These practices can also increase cropland greenhouse gas emissions like methane. • More empirical data is needed to quantify the practices' effects on soil carbon [ABSTRACT FROM AUTHOR]

Biochar has received increasing attention in agricultural and environmental fields as an integrated solution to agricultural waste recycling, soil amendment, carbon sequestration, and greenhouse gas (GHG) reduction. However, obtaining the environmental benefits of biochar is limited by an inadequate number of soil applications. Currently, the willingness to use biochar in soil management is relatively low, which results from the insufficient understanding and promotion of the roles of biochar in soil management and climate change mitigation. This review article presents biochar applications based on carbon-neutral strategies in agricultural soil systems. The primary roles of biochar in soil improvement and remediation are discussed and the main soil application methods are introduced. The focus of this article is on biochar-based soil management strategies for contributing to carbon neutrality. Carbon sequestration using biochar is an application-dependent strategy, as the key to obtaining this ecological benefit is to store biochar products in soil via effective agricultural management. This article offers insights into biochar-based soil management strategies and their contribution to carbon neutrality in agricultural soil systems, with recommendations for appropriate government involvement in promoting biochar-based soil management and for incorporating biochar into the carbon trading market. • The non-CO 2 GHGs account for the majority of carbon emission via agricultural soil. • Incorporating biochar into the global carbon trading market is recommended. • Using biochar to help achieve carbon neutrality is an application-dependent strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Agriculture/climate relationship is one of the most important contemporary problems. • Agriculture is a significant source of GHG emissions and carbon sequestration. • Agriculture must minimize greenhouse gas emissions without reducing yields. • Integrating trees with agricultural landscapes is strategy in climate change mitigation. Agronomy has significant impacts on climate stability due to the emission of large amounts of greenhouse gases and C sequestration in soil and plants and can influence on reducing the negative impact of agronomy on climate does not need to result in a reduction in yield. Nevertheless, satisfying both goals require the implementation of new methods. The present assessment was based on over 190 scientific publications. Forecasts from the beginning of the 21st century showed that the increase in temperature and CO 2 concentration would improve the productivity of crops by extending the growing season and allow for the cultivation of new species. However, this beneficial effect may be limited by the increasing intensity of the extreme weather phenomena such as: rainstorm, droughts, early frosts, storms etc. Here, we review more recent studies which indicate, however, that this beneficial effect of climate change will not be permanent and, consequently, will significantly reduce crop yields. Climate change is forcing the agronomy sector to implement adaptive methods for minimizing possible crop losses consisting, inter alia, (i) using crop species/varieties that are less sensitive; (ii) optimizing water management; (III) improving pest, disease and weed control efficiency. The pressure on the agriculture sector to increase food production due to the increase in the human population and the present hunger in specific regions run counter to the need to reduce the adverse climate impacts of agriculture. The current state of knowledge indicates that despite the implementation of new technologies, agricultural measures will not be able to significantly reduce climate change. Indeed, these approaches will not replace the need to reduce greenhouse gas emissions in other sectors. However, without the participation of agronomy in reducing GHG emissions by increasing carbon sequestration, the goals of the 2015 UN Climate Change Conference in Paris will not be achieved. [ABSTRACT FROM AUTHOR]

This study examines how the proposed American Clean Energy and Security Act (H.R. 2454) would affect U.S. agriculture with special reference to water resources. The bill's cap and trade provisions for greenhouse gases would significantly raise fertilizer, irrigation pumping, and other energy-related costs. By 2030, it would reduce U.S. irrigation water use by >11 percent and fertilizer use by >18 percent with positive implications for water conservation and quality. Carbon offset provisions create financial incentives for farmers to sequester carbon by planting trees on cropland, reducing agricultural production and raising prices. Because sequestration potential differs by region, most of the estimated 51 million acres of converted cropland would be in the Corn Belt and Mississippi Delta. Afforestation would reduce Delta water use further, but increase water use in other regions compared to cap and trade alone. Compared to a no-policy baseline, irrigation water use declines 10 percent nationally, but increases in the Southern Plains. H.R. 2454 may have significant water conservation effects in some regions, but increase competition for water in others. By reducing fertilizer use and dramatically altering land use patterns in parts of the Mississippi Basin, it may also provide unexpected water quality benefits. Unintended water use and quality consequences of climate policies merit further research. [ABSTRACT FROM AUTHOR]

Emission of greenhouse gases has become a matter of major concern; nations are struggling to lower the greenhouse gas emissions because of its adverse effects on life. There is dire need to lower the source size and enlarge the sinks of green house gases. Reducing CO2 concentration in the atmosphere by enhancing the rates of removal of the atmospheric CO2 through carbon sequestration is considered as one of the best climate change mitigation strategy. Carbon sequestration is the issue of international interest due to its potential impact on agriculture and climate change. Oceans, soils, geological formations, mangroves, bogs, agriculture and agro forestry serves carbon sequesters. Although intensive agriculture is a source of carbon emission, it can be converted to sink with proper management. Policies to reduce climate change using natural ecosystems to sequester and store carbon should be accompanied by technological solutions to further reduce the impacts of climate change. [ABSTRACT FROM AUTHOR]

Potential interactions between food production and climate mitigation are explored for two situations in sub-Saharan Africa. where deforestation and land degradation overlap with hunger and poverty. Three agriculture intensification scenarios for supplying nitrogen to increase crop production (mineral fertilizer, herbaceous legume cover crops-green manures-and agroforestry- legume improved tree fallows) are compared to baseline food production, land requirements to meet basic caloric requirements, and greenhouse gas emissions. At low population densities and high land availability, food security and climate mitigation goals are met with all intensification scenarios, resulting in surplus crop area for reforestation. In contrast, for high population density and small farm sizes, attaining food security and reducing greenhouse gas emissions require mineral fertilizers to make land available for reforestation; green mantire or improved tree fallows do not provide sufficient increases in yields to permit reforestation. Tree fallows sequester significant carbon on cropland, but green manures result in net carbon dioxide equivalent emissions because of nitrogen additions. Although these results are encouraging, agricultural intensification in sub-Saharan Africa with mineral fertilizers, green manures, or improved tree fallows will remain low without policies that address access, costs, and lack of incentives. Carbon financing for small-holder agriculture could increase the likelihood of success of Reducing Emissions from Deforestation and Forest Degradation in Developing Countries programs and climate change mitigation but also promote food security in the region. [ABSTRACT FROM AUTHOR]

Abstract: Soil C sequestration in cropland could play an important role in mitigating the rapidly increasing CO2 emissions in China. Many efforts had been dedicated to estimating the potential for C sequestration in croplands. Potential increases in SOC in China''s croplands had been recently evaluated using inventory-up-scaling simulation and crop-soil C process-based modeling. In this study, data of SOC change at monitoring sites from croplands across mainland China were collected from publications available from 1985 to 2006 to perform a statistical analysis. The data set comprises 1081 observations (404 from rice paddies, RPs and 677 from dry croplands, DCs). Frequency analysis indicates that over 70% of observations show an increase in SOC, which is higher among RPs than DCs. To quantify SOC dynamics, a Relative Annual Change Index in gkg−1 year−1 (RAC, gkg−1 year−1) is defined and calculated using the initial and final SOC values for the duration of monitored observations. RAC values ranged from −0.806 to 0.963gkg−1 year−1 for DCs and from −0.597 to 0.959gkg−1 year−1 for RPs, respectively. From this data, the average is estimated to be 0.056±0.200gkg−1 year−1 for DCs, and 0.110±0.244gkg−1 year−1 for RPs, with an overall estimate for China''s croplands, with RPs and DCs combined, of 0.076±0.219gkg−1 year−1. A mean increase in topsoil C (0–20cm) stock of China''s croplands was estimated to be 25.5TgCyear−1 (8TgCyear−1 in RPs and 17.5TgCyear−1 in DCs) between 1985 and 2006, with a total topsoil C stock increase of 0.64 Pg C over the whole period. The annual stock increase may offset ∼20%, on average, of the total CO2 emissions of China for 1994. This study suggests an important role of China''s croplands, especially rice paddies, for C sequestration to mitigate climate change. [Copyright &y& Elsevier]

Forestry and land-use change are often considered in the context of a greenhouse gas cap-and-trade program, in recognition of their influence on net carbon flux and their ability to mitigate climate change via increased carbon sequestration. The climatic impacts of forests are not limited to atmospheric greenhouse gas concentrations, however, and a growing body of research suggests that albedo-related climatic changes stemming from land-use change may diminish or counteract the climatic benefits of sequestration. Because forests are generally darker than bare or agricultural land they absorb relatively more solar radiation, which may exert a local warming influence. This phenomenon is known as the "albedo effect." Thus, a "carbon-only" accounting approach that ignores albedo impacts can significantly overestimate the climatic benefit of offsets, in particular, afforestation. In the worst case this could result in a forest offset actually contributing to warming and, in general, may reduce the environmental effectiveness of some forest offsets. Therefore a cap-and-trade system design question is whether to recognize the albedo effect into forest offset accounting frameworks. We propose that forest offset design moves toward a "carbon-equivalent" accounting approach that aggregates the climatic impacts of sequestration and of surface albedo when evaluating forest offset projects. This change would result in climate mitigation efforts taking a more targeted geographic approach that emphasizes maintaining or increasing forest cover in the tropics, and that avoids afforestation in boreal and high-latitude temperate regions. Currently developing regional cap-and-trade systems in North America, however, give afforestation projects priority for offset consideration. By staying on the current path, efforts in these initiatives directed toward forest offsets may be inefficient or ineffective and, at worst, counterproductive, in large parts of the area they cover. Incorporating both carbon and albedo effects into policymaking will lead to more informed and effective forest offset design. [ABSTRACT FROM AUTHOR]

Assessing the contribution of terrestrial carbon sequestration to climate change mitigation requires integration across scientific and disciplinary boundaries. A comprehensive analysis incorporating ecologic, geographic and economic data was used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric greenhouse gas stabilization by 2100. Terrestrial sequestration reaches a peak rate of 0.5–0.7GtCyr−1 in mid-century with contributions from agricultural soils (0.21GtCyr−1), reforestation (0.31GtCyr−1) and pasture (0.15GtCyr−1). Sequestration rates vary over time and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 23 to 41GtC. [Copyright &y& Elsevier]

Global climate is undergoing significant changes due to extensive release of greenhouse gases (GHGs) such as CO2 and methane in the atmosphere. These gases are produced and released as a result of anthropogenic activities and fossil fuel burnings which also result in depletion of soil carbon resources. Biochar has various distinctive properties, which contribute to make it an effective, economical, and eco-friendly approach for soil carbon sequestration. The versatility in physicochemical properties of biochar provides an opportunity to optimize its efficacy to obtain desired benefits. A critical review of the literature indicates that biochar and plant growth–promoting microbes have the potential to improve soil organic carbon (SOC). Recent studies have depicted a significant role of the combined application of plant growth–promoting microbes and biochar on SOC dynamics. In future, these areas need to be explored as these have the potential to improve SOC dynamics and it could be a better strategy to sustain natural resources and ultimately mitigation of the climate change. [ABSTRACT FROM AUTHOR]

There has been a careless use of terminology like “climate change mitigation” and “mitigate global warming” in scientific papers on no-tillage management in agriculture. This is because it has yet to be shown unequivocally that no-tillage can lead to carbon (C) sequestration let alone climate change mitigation. I briefly summarize evidence that shows that the claims of climate change mitigation through no-tillage agriculture are highly overstated. [ABSTRACT FROM AUTHOR]