Carbon sequestration by ecosystems of cold territories of Transbaikalia

Peatlands play an important role in global climate regulation and carbon (C) cycling. To evaluate the potential effect of peatland restoration on greenhouse gas (GHG) emission mitigation, and preservation of peat C stock or enhancement of atmospheric carbon dioxide (CO2) sequestration, we used a manual chamber method to measure soil heterotrophic respiration CO2 emissions (Rhet) and ecosystem GHG emissions. Ecosystem emission measurements included methane (CH4), nitrous oxide (N2O) emissions and forest floor CO2 emissions (Rfloor) in forested peatlands or ecosystem CO2 emissions (Reco) in peatlands without tree cover. Measurements of Reco and Rfloor were conducted using chambers that included all vegetation present in the ecosystem or ground vegetation, respectively. Rhet measurements were performed after the removal of ground vegetation and litter layer and trenching of the roots. In addition to GHG emission measurements, C input into the soil with vegetation litter was estimated, and environmental variables (including soil temperature and moisture, groundwater level, water chemistry and others) that potentially can affect the magnitude of GHG emissions were monitored. The monitoring was initiated in 2023 and continued in 2024 at seven study sites located in raised bogs within the hemiboreal vegetation zone of Europe, specifically in Latvia. Study sites included different habitats of pristine peatlands, restored peatlands through rewetting, and areas in both strong and weak drainage impact zones where the development of woody vegetation characteristic of the forest ecosystem has occurred. Preliminary results of GHG emission measurements show that the annualized monthly mean ecosystem gross GHG emissions, expressed in CO2 equivalents (excluding C sequestration by vegetation), ranged from 9.7 to 45.9 t CO2 eq. ha−1 year−1 in degraded (drained) peatlands, while in restored (including rewetted) peatland GHG emissions ranged from 11.0 to 25.3 t CO2 eq. ha−1 year−1.Acknowledgements: The research was conducted within the scope of the European Commission LIFE Climate Action Programme Project “Peatland restoration for greenhouse gas emission reduction and carbon sequestration in the Baltic Sea region” (LIFE21 - CCM - LV - LIFE PeatCarbon, Project number: 101074396).

This paper reviews the research conducted by ICRISAT and its partners on the role of management systems on carbon sequestration and crop productivity in the semi‐arid regions of India. It is now established that apart from water shortages, the dryland productivity is also constrained by low fertility mainly caused by the low organic matter status of most soils. Sequestration of atmospheric carbon dioxide in the soil has the potential to achieve the multiple objectives of improving the soil quality and fertility of the semi‐arid tropical soils, increasing crop productivity, improving livelihoods and maintaining environmental quality.

Many believe that conservation tillage practices could increase the sequestration of atmospheric carbon dioxide into agricultural soils and this sequestered carbon may partially offset the greenhouse gas effect and thus reduce the impact of global warming. Recent advances in soil carbon (C) and greenhouse gas analysis have made it possible to evaluate the impacts of conservation tillage on C sequestration from various perspectives. Although conservation tillage favors soil and water conservation, there are biased estimates of C sequestration associated with conservation tillage, and it is particularly an issue for a “pure” no-tillage (NT) system. Accordingly, this paper presents an overview of the progress achieved in evaluating C sequestration in no-till (the extreme type of conservation tillage) and conventional tillage production systems. In addition to extended discussion of how soil sampling and calculations could influence the estimates of C gains or losses in no-till versus conventional tilled soil, this review will also focus on following aspects, including (1) the impact of NT on crop yields which governs organic C inputs to soil from crop residue, (2) the impact of NT on soil organic C mineralization which is a major pathway of soil C output, and (3) the roles of the initial levels of C stocks and soil erosion rates which are crucial for estimating soil C sequestration under different tillage systems. Many soil C studies have indicated that the impacts of NT on soil C sequestration are compounded by many factors and should not be generalized.

Multi-functional silvopastoral systems provide a wide range of services to human society including the regulation of nutrients and water in soils and the sequestration of atmospheric carbon dioxide (CO2). Although silvopastoral systems significantly contribute to enhance aboveground carbon (C) sequestration (e.g. C accumulation in woody plant biomass), their long-term effects on soil C pools are less clear. In this study we performed soil physical fractionation analyses to quantify the C pool of different aggregate fractions across three land use types including (1) silvopastoral system with ash trees (Fraxinus excelsior L.), (2) planted woodland with ash trees, and (3) permanent grassland, which were established in 1989 at Loughgall, Northern Ireland, UK. Our results show that 26 years after the conversion of permanent grassland to either silvopastoral or woodland systems, soil C (and N) stocks (0–20 cm depth) did not significantly change between the three land use types. We found, however, that permanent grassland soils were associated with significantly higher C pools (g C kg−1 soil; P < 0.03) of the large macro-aggregate fraction (> 2 mm) whereas soil C pools of the micro-aggregate (53–250 μm) and silt and clay (< 53 μm) fractions were significantly higher in the silvopastoral and woodland systems (P < 0.05). A key finding of this study is that while tree planting on permanent grassland may not contribute to greater soil C stocks it may, in the long-term, increase the C pool of more stable (recalcitrant) soil micro-aggregate and silt and clay fractions, which could be more resilient to environmental change.

The increase in atmospheric concentrations of carbon dioxide contributes to global warming to a large extent. In this context biological sequestration of carbon dioxide hold promise as a means for addressing this problem. In the present study atmospheric carbon dioxide sequestration is achieved with the help of carbonic anhydrase produced by Bacillus schlegelii. A maximum activity of 0.0453 µ mol/ml/min was observed at pH 9 and 37 0 C. The enzyme was active up to 70 0 C.

Задачи установления и оценивания составляющих речного стока приобретают большую актуальность в связи с необходимостью развития углубленных представлений о механизмах стокоформирования. Их решение способствовало бы пониманию многих связанных вопросов, касающихся условий формирования химического состава речных вод, характера взаимодействия поверхностных и подземных вод, уточнения ресурсных оценок источников питания речного стока. Структура водных масс в речных бассейнах более разнообразна и не полностью отражена в классических классификациях источников питания по генезису, подземного питания рек, что вызывает необходимость их дополнения и детализации. Целью данной работы является обобщение накопленного российского опыта тестирования диагностических процедур ЕММА-моделирования в идентификации источников питания речного стока и их оценке по данным гидрологических измерений и гидрохимических съемок. Исследуемые объекты – экспериментальные водосборы малых и средних рек, которые располагаются в различных физико-географических условиях и имеют принципиальные различия в характере источников питания. Географический охват тестирования и адаптации модели включает водосборы, расположенные на территории Дальнего Востока, в криолитозоне, в Прибайкалье, в Восточно-Европейской части России, в Горном Крыму. Обсуждаемый подход диагностического моделирования стокоформирования на основе ЕММА включает интеграцию двух типов моделей: 1) физической модели смешения в виде системы балансовых уравнений для воды и трассеров и 2) проекционного метода главных компонент из класса формально-математических моделей. В работе систематизируются полученные ранее итоговые результаты ЕММА-моделирования: наборы химических трассеров, используемые при адаптации модели смешения по каждому водосбору, и выделенные типы речного стока. Наиболее часто свойства консервативности проявляют химические трассеры: минерализация воды (или удельная электропроводность), гидрокарбонат-ион, сульфат-ион. Меньшее число раз провляют консервативные свойства ионы кальция, магния, натрия, растворенного кремния. Высокие индикативные свойства в разделении подверхностного почвенно-склонового стока на компоненты стока с органогенных почвенных и минеральных горизонтов проявляет растворенный органический углерод. Выявленные разнообразные типы подповерхностного стока показывают эффективность диагностического ЕММА-моделирования при исследовании структуры речного стока, установления ее региональной специфики, обусловленной различными ландшафтным обстановкам в бассейнах. Продемонстрированные возможности оценки составляющих речного стока любой временной динамики (суточной, сезонной, паводковой) открывают перспективы углубленного понимания механизмов стокообразования. The challenges of identification and assessing the river runoff components are becoming increasingly relevant due to the need to develop in-depth understanding of runoff generation mechanisms. Their solution would contribute to the understanding of many related issues concerning the formation of the chemical composition of river waters, the nature of the interaction of surface and groundwater, and enhancement of resource estimates of river runoff components. The structure of water masses in river catchments is multiplicity and is not fully reflected in the classical classifications - river runoff water sources dividing by genesis, classification of groundwater flow types to rivers, which make it necessary their addition and detail. The aim of this work is to summarize the accumulated experience in Russian for testing diagnostic procedures of EMMA-modeling in identifying sources of river runoff components and their assessment with using data of hydrological and hydrochemical measurements. The objects under study are experimental watersheds of small and medium-sized rivers, which are located in different physical and geographical conditions and have fundamental distinctive feature in the nature of water sources. The geographic scope of testing and adaptation of the model includes watersheds located in the Far East (the Ussuri River basin), in the permafrost zone in the far north (the Yanranaivaam River basin, Chukotka), on its southern border – the Mogot hydrological test site (the Gilyuy River basin, zone of Baikal-Amur Mainline Railway), on the territory of the Sarma geoecological test site in the Baikal region (the Sarma river basin), in the zone of mixed forests of the East European Plain (the Zapadnay Dvina river basin), in the area of the distribution of karst in the Crimean Mountains (the Belbek and the Biyuk-Karasu river basins). The discussed approach of diagnostic modeling of runoff formation based on EMMA includes the integration of two types of models: 1) a physical mixing model in the form of a system of balance equations for water and chemical tracers and 2) the projection method of principal component analysis from the class of formal mathematical models. This work systematizes the final results of EMMA modeling previously obtained by the authors: sets of chemical tracers used in adapting the mixing model, and identified types of river runoff components in experimental catchments. Chemical tracers which most often exhibit conservative hypothesis: water mineralization (or specific electrical conductivity), bicarbonate ion, sulfate ion. Calcium, magnesium, sodium, and dissolved silicon ions exhibited conservative properties a smaller number of times. Dissolved organic carbon exhibits high indicative properties in the separation of subsurface soil-slope runoff into runoff components from organic soil and mineral horizons. The identified various types of subsurface flow show the effectiveness of diagnostic EMMA-modeling in research the structure of river flow, establishing its regional specificity, due to different landscape situations in the basins. The demonstrated possibilities of assessing the components of river flow of any time dynamics (daily, seasonal, flood) opens up prospects for an in-depth understanding of the mechanisms of runoff formation.

Forest biomass helps mitigate climate change impacts through sequestration of atmospheric carbon dioxide and potentially storing it for long periods of time. Deforestation and timber harvesting cause the reduction of forest biomass resulting in the reduced carbon sequestration capacity and alterednatural balance of forest ecosystems. We used remote sensing and GIS tools in the four important forest cover zones within five districts of Bangladesh to compare the aboveground forest biomass (AGB) changes between 2014 and 2020. We found an increased AGB in Sundarban mangrove forest from 89.73 Mg.h-1 in 2014 to 90.76 Mg.h-1 in 2020. Similarly, the AGB was found to be increased for Ukhiya hill forest from 7.89 Mg.h-1 in 2014 to 8.89 Mg.h-1 in 2020. Contrary, the average AGB content in Nijhum Dwip mangrove forest decreased from 44.36 Mg.h-1 in 2014 to 37.46 Mg.h-1 in 2020. The average AGB of Modhupur decidious forest also found to be decreased from 110.01 Mg.h-1 in 2014 to 107.22 Mg.h-1 in 2020. The decreased biomass contents could be attributed to anthropgenic factors as indicated by the presence of human activities and this informatin will be helpful for forest restoration and management in Bangladesh.

Carbon is sequestered in soils by accumulation of recalcitrant organic matter and by bicarbonate weathering of silicate minerals. Carbon fixation by ecosystems helps drive weathering processes in soils and that in turn diverts carbon from annual photosynthesis-soil respiration cycling into the long-term geological carbon cycle. To quantify rates of carbon transfer during soil development in moist temperate grassland and desert scrubland ecosystems, we measured organic and inorganic residues derived from the interaction of soil biota and silicate mineral weathering for twenty-two soil profiles in arkosic sediments of differing ages. In moist temperate grasslands, net annual removal of carbon from the atmosphere by organic carbon accumulation and silicate weathering ranges from about 8.5 g m−2 yr−1 for young soils to 0.7 g M−2 yr−1 for old soils. In desert scrublands, net annual carbon removal is about 0.2 g m−2 yr−1 for young soils and 0.01 g m−2 yr−1 for old soils. In soils of both ecosystems, organic carbon accumulation exceeds CO2 removal by weathering, however, as soils age, rates of CO2 consumption by weathering accounts for greater amounts of carbon sequestration, increasing from 2% to 8% in the grassland soils and from 2% to 40% in the scrubland soils. In soils of desert scrublands, carbonate accumulation far outstrips organic carbon accumulation, but about 90% of this mass is derived from aerosolic sources that do not contribute to long-term sequestration of atmospheric carbon dioxide.

Carbon storage capacity of monoculture and mixed-species plantations in subtropical China

Evaluation of forest carbon uptake in South Korea using the national flux tower network, remote sensing, and data-driven technology

The need to stabilize the greenhouse gas concentrations of the atmosphere is the great environmental challenge of this century. To control these concentrations, humanity can reduce fossil fuel emissions and/or identify mechanisms to remove greenhouse gases once they have been emitted. The scope of the problem is challenging because of the size of the fluxes involved. Presently, industry, transportation, and domestic use emits nearly 10 Gt C to the atmosphere annually, and there is no immediate hope for a drastic reversal of these rates of emission (1). Thus, sequestration of atmospheric carbon dioxide as organic carbon in the biosphere attracts attention as an alternate way to help stem the rate of greenhouse gas growth and associated changes in our climate. Some soil researchers have suggested that altered agricultural techniques can help restore much carbon to domesticated soils, thus helping mitigate climate change. But cultural and scientific challenges suggest that this proposition is overly optimistic and inherently flawed. Image courtesy of ScienceSource/Jerry Irwin. For nearly 2 decades, researchers in the soil science community have studied and estimated the potential of sequestering carbon in soil organic matter (2, 3). The premise is inherently rational: nearly 10,000 years of cultivated agriculture has reduced global soil carbon by 116 Gt (4), an amount equivalent to more than a decade of the present rates of industrial emissions. Through changed agricultural techniques, it is proposed, much of this carbon can be restored to domesticated soils and thus serve as a significant tool to mitigate climate change, providing a wider timeframe for society to decarbonize. Unfortunately, both cultural and scientific challenges suggest that this proposal is overly optimistic and inherently flawed. Nevertheless, this long and relatively well-funded (5) area of research recently gained novel international exposure because of the unveiling of the French “4 per mille” … [↵][1]1To whom correspondence should be addressed. Email: earthy{at}berkeley.edu. [1]: #xref-corresp-1-1

Chapter 37 - Climate-smart integrated soil fertility management in fruit crops: An overview

Forestry – including afforestation (the planting of trees on land where they have not recently existed), reforestation, avoided deforestation, and forest management – can lead to increased sequestration of atmospheric carbon dioxide and has therefore been proposed as a strategy to mitigate climate change. However, forestry also influences land‐surface properties, including albedo (the fraction of incident sunlight reflected back to space), surface roughness, and evapotranspiration, all of which affect the amount and forms of energy transfer to the atmosphere. In some circumstances, these biophysical feedbacks can result in local climate warming, thereby counteracting the effects of carbon sequestration on global mean temperature and reducing or eliminating the net value of climate‐change mitigation projects. Here, we review published and emerging research that suggests ways in which forestry projects can counteract the consequences associated with biophysical interactions, and highlight knowledge gaps in managing forests for climate protection. We also outline several ways in which biophysical effects can be incorporated into frameworks that use the maintenance of forests as a climate protection strategy.

Carbonate formation in waste from the steel industry could constitute a nontrivial proportion of the global requirements for removing carbon dioxide from the atmosphere at a potentially low cost. To utilize this potential, we examined atmospheric carbon dioxide sequestration in a >20 million ton legacy slag deposit in northern England, United Kingdom. Carbonates formed from the drainage water of the heap had stable carbon and oxygen isotope values between -12 and -25 ‰ and -5 and -18 ‰ for δ13C and δ18O, respectively, suggesting atmospheric carbon dioxide sequestration in high-pH solutions. From the analyses of solution saturation states, we estimate that between 280 and 2900 tons of CO2 have precipitated from the drainage waters. However, by combining a 37 year long data set of the drainage water chemistry with geospatial analysis, we estimate that <1% of the maximum carbon-capture potential of the deposit may have been realized. This implies that uncontrolled deposition of slag is insufficient to maximize carbon sequestration, and there may be considerable quantities of unreacted legacy deposits available for atmospheric carbon sequestration.

The costing of carbon credits from ocean nourishment plants