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1.
J Environ Manage ; 288: 112478, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33823451

RESUMEN

The spatiotemporal dislocation of urbanization and ecological construction may lead to differences in the spatiotemporal pattern and matching of the ecosystem service supply and demand, which are significantly important in altering the ecosystem service supply and demand equilibrium. This study quantified and mapped the supply and demand of carbon sequestration services in the Xiangjiang River Basin (XRB) from 1990 to 2015 using the InVEST and population distribution models and identified the spatial distribution characteristics and changes in the supply and demand relationship on the sub-basin scale using the spatial autocorrelation method and Z-scores. The results show that the expansion of land urbanization greater than 50% was concentrated in the midstream and downstream, while the ecological construction was mainly distributed in the upstream. On the whole-basin scale, the supply of carbon sequestration services slightly decreased by 21.62%, while the demand sharply increased by 376.86%. The carbon sequestration services supply-demand ratio (CSDR) reduced from 0.16 (1990) to -0.03 (2015). This meant that the status of the supply and demand in the XRB had changed from oversupply to overdemand, and this tide turned in 2005 (-0.01). Furthermore, the spatial distribution pattern of the sub-basins' CSDR in the upstream was the High-High cluster, while it was the Low-Low cluster in the downstream. These results revealed the high spatial distribution consistency between the CSDR and urbanization and ecological construction. The slight increase in the carbon sinks caused by the ecological construction in the upstream could not offset the rapidly increased carbon emissions from the downstream for urbanization. Meanwhile, the lack of ecological concern during the urbanization process had led to a persistent reduction in the carbon sinks in the downstream, which also exacerbated the disequilibrium of the ecosystem service supply and demand in the XRB. Consequently, this study suggests that the scale and speed of the urbanization of land should be reasonably controlled and that the ecological construction in rapid urbanization regions should be strengthened to meet the demand for ecosystem services.


Asunto(s)
Ecosistema , Urbanización , Carbono , Secuestro de Carbono , China , Conservación de los Recursos Naturales , Ríos
2.
J Environ Manage ; 289: 112458, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33823412

RESUMEN

Organic rice farming is a sustainable rice cultivation system that eliminates chemical inputs and has the potential to reduce environmental impacts. This study aims to: 1) evaluate and compare the carbon footprint intensity and the value of carbon sequestration ecosystem services (VCSES) between organic rice farming (OF) and conventional rice farming (CF) and 2) estimate the impact of climate change on soil organic carbon (SOC), rice yield, and VCSES of two farming types in Phichit province, Thailand. The results showed that the carbon footprint intensity in OF and CF were significantly different with -0.13 and 0.82 kg CO2eq kg-1 rice yield, respectively. The differences in SOC stocks (ΔSOCS) were more significant in OF with the increase of 1107.6 kg C ha-1 year-1 (4061.2 kg CO2eq ha-1 year-1), while the ΔSOCS value in CF was 625 kg C ha-1 year-1 (2291.7 kg CO2eq ha-1 year-1). The VCSES in OF (541,196 US$ ha-1 year-1) was nearly two times higher than in CF (305,388 US$ ha-1 year-1). Under future climate change, rice yields of both farming types are expected to increase under Representative Concentration Pathway (RCP) 2.6, RCP4.5, and RCP6.0, and it will decline under RCP8.5. The SOC and VCSES values are predicted to increase, except under RCP8.5. The dramatic declines can be found from the near future (2020-2039) to the very far future (2080-2099) period. Our finding indicates that even though climate change will have negative effects on SOC and VCSES, the OF will have less impact compared with CF.


Asunto(s)
Secuestro de Carbono , Oryza , Agricultura , Carbono/análisis , Huella de Carbono , Cambio Climático , Ecosistema , Suelo , Tailandia
3.
Nat Commun ; 12(1): 2138, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-33837222

RESUMEN

It is largely unknown how South America's Andean forests affect the global carbon cycle, and thus regulate climate change. Here, we measure aboveground carbon dynamics over the past two decades in 119 monitoring plots spanning a range of >3000 m elevation across the subtropical and tropical Andes. Our results show that Andean forests act as strong sinks for aboveground carbon (0.67 ± 0.08 Mg C ha-1 y-1) and have a high potential to serve as future carbon refuges. Aboveground carbon dynamics of Andean forests are driven by abiotic and biotic factors, such as climate and size-dependent mortality of trees. The increasing aboveground carbon stocks offset the estimated C emissions due to deforestation between 2003 and 2014, resulting in a net total uptake of 0.027 Pg C y-1. Reducing deforestation will increase Andean aboveground carbon stocks, facilitate upward species migrations, and allow for recovery of biomass losses due to climate change.


Asunto(s)
Secuestro de Carbono/fisiología , Carbono/metabolismo , Cambio Climático , Conservación de los Recursos Naturales , Árboles/metabolismo , Biomasa , Bosques , América del Sur , Clima Tropical
4.
J Environ Manage ; 286: 112191, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33667822

RESUMEN

The sustainable land management program (SLMP) of Ethiopia aims to improve livelihoods and create resilient communities and landscape to climate change. Soil organic carbon (SOC) sequestration is one of the key co-benefits of the SLMP. The objective of this study was to estimate the spatial dynamics of SOC in 2010 and 2018 (before and after SLMP) and identify the SOC sequestration hotspots at landscape scale in four selected SLMP watersheds in the Ethiopian highlands. The specific objectives were to: 1) comparatively evaluate SOC sequestration estimation model building strategies using either a single watershed, a combined dataset from all watersheds, and leave-one-watershed-out using Random Forest (RF) model; 2) map SOC stock of 2010 and 2018 to estimate amount of SOC sequestration and potential; 3) evaluate the impacts of SLM practices on SOC in four SLMP watersheds. A total of 397 auger composite samples from the topsoil (0-20 cm depth) were collected in 2010, and the same number of samples were collected from the same locations in 2018. We used simple statistics to assess the SOC change between the two periods, and machine learning models to predict SOC stock spatially. The study showed that statistically significant variation (P < 0.05) of SOC was observed between the two years in two watersheds (Gafera and Adi Tsegora) whereas the differences were not significant in the other two watersheds (Yesir and Azugashuba). Comparative analysis of model-setups shows that a combined dataset from all the four watersheds to train and test RF outperform the other two strategies (a single watershed alone and a leave-one-watershed-out to train and test RF) during the testing dataset. Thus, this approach was used to predict SOC stock before (2010) and after (2018) land management interventions and to derive the SOC sequestration maps. We estimated the sequestrated, achievable and target level of SOC stock spatially in the four watersheds. We assessed the impact of SLM practices, specifically bunds, terraces, biological and various forms of tillage practices on SOC using partial dependency algorithms of prediction models. No tillage (NT) increased SOC in all watersheds. The combination of physical and biological interventions ("bunds + vegetations" or "terraces + vegetations") resulted in the highest SOC stock, followed by the biological intervention. The achievable SOC stock analysis showed that further SOC stock sequestration of up to 13.7 Mg C ha--1 may be possible in the Adi Tsegora, 15.8 Mg C ha-1 in Gafera, 33.2 Mg C ha-1 in Azuga suba and 34.7 Mg C ha-1 in Yesir watersheds.


Asunto(s)
Carbono , Suelo , Agricultura , Secuestro de Carbono , Conservación de los Recursos Naturales , Etiopía
5.
J Environ Manage ; 286: 112272, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33677337

RESUMEN

The recycling of biogas residues resulting from the anaerobic digestion of organic waste on agricultural land is among the means to reduce chemical fertilizer use and combat climate change. This in sacco decomposition study investigates (1) the potential of the granulated biogas residue fraction to provide nutrients and enhance soil carbon sequestration when utilized as exogenous organic matter in grassland soils, and (2) the impact of different nitrogen fertilizers on the organic matter decomposition and nutrient release processes. The experiment was conducted in two permanent grasslands of the Greater Region over one management period using rooibos tea as a comparator material. The decomposition and chemical changes of the two materials after incubation in the soil were assessed by measuring the mass loss, total carbon and nitrogen status, and fibre composition in cellulose, hemicellulose and lignin. Overall, after the incubation period, granulated biogas residue maintained up to 68% of its total mass, organic matter and total carbon; increased its content in recalcitrant organic matter by up to 45% and released 45% of its total nitrogen. Granulated biogas residue demonstrated resilience and a higher response uniformity when exposed to different nitrogen fertilizers, as opposed to the comparator material of rooibos tea. However, the magnitude of fertilizer-type effect varied, with ammonium nitrate and the combinatorial treatment of raw biogas residue mixed with urea leading to the highest organic matter loss from the bags. Our findings suggest that granulated biogas residue is a biofertilizer with the potential to supply nutrients to soil biota over time, and promote carbon sequestration in grassland soils, and thereby advance agricultural sustainability while contributing to climate change mitigation.


Asunto(s)
Secuestro de Carbono , Suelo , Agricultura , Biocombustibles , Carbono , Fertilizantes/análisis , Pradera , Nitrógeno/análisis
6.
Environ Monit Assess ; 193(4): 205, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33751246

RESUMEN

Global anthropogenic damage is caused when humans aim to improve their welfare by social and economic activities. From this vantage, this paper seeks to determine priority locations for afforestation areas and carbon sinks by using socio-economic and ecological variables. Factor analysis is performed on degraded forest areas (DEGFRST), the ratio of non-forest areas to provincial general area (NFL), average of total monthly rainfall (ATMR), air pollution (PM10), the amount of migration (AMGR), annual average population density (AAPD), gross domestic product by industrial activity (I_GDP), socio-economic development index (SEDI) of provinces, export (EXP) and import (IMP) amount of provinces, average number of cars per one thousand people (ACNPT), and average electricity consumption per person (AECPP) variables for all provinces in Turkey (KMO = 0.802, Bartlett's χ2 = 832.191, and p < 0.0001). Principal component analysis is used as a factor extraction method. Based on the three components obtained (explaining 74.730% of the total variance), the factor scores of 81 provinces were analyzed geostatistically using the Kriging interpolation method. The final map of potential afforestation areas was created using three-factor maps and factor variances, according to weighted overlay analysis. As a result of this study, afforestation priority areas in Turkey were identified based on three components. In subsequent studies, by increasing the number of variables used in this study, strategies for increasing Turkey's carbon sinks can be planned. Evaluating socio-economic and ecological factors together in afforestation studies can contribute to balancing human impact and conservation through alternative approaches.


Asunto(s)
Contaminación del Aire , Monitoreo del Ambiente , Secuestro de Carbono , China , Bosques , Humanos , Turquia
7.
Ying Yong Sheng Tai Xue Bao ; 32(3): 799-809, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33754544

RESUMEN

Forests play an important role in regulating climate change and maintaining carbon balance. To explore the carbon storage and carbon sequestration rate of national forest parks is of great significance for carbon sequestration capacity assessment and sustainable forest management. A process-based ecosystem model (CEVSA2 model) was used to simulate the spatial distribution of carbon density, carbon storage and carbon sequestration rate of 881 national forest parks in China during 1982-2017. The results showed that the average carbon density of national forest parks was 255.18 t C·hm-2, being higher than the average carbon density of forest ecosystem in China. In 2017, the total carbon storage of national forest parks increased to 3.56 Pg C, accounting for 11.0%-12.2% of the total carbon storage in national forest ecosystems. During 1982-2017, the average carbon sequestration rate of national forest parks reached 0.45 t C·hm-2·a-1, and the carbon sequestration rate of all national forest parks was above 0.30 t C·hm-2·a-1. National forest parks in the northeast and southwest of China had the highest total carbon storage. The national forest parks in northeast of China had the highest soil organic carbon sequestration rate, while those in eastern China and central southern China had the highest biomass carbon sequestration rate. The area of national forest parks accounted for 5.8% of the total forest area of China, playing an important role in forest carbon sink management of China. Accurate assessment of the growth status, carbon sequestration potential and carbon absorption characteristics of national forest parks could provide reference for the comprehensive assessment of ecosystem service of forest parks in China.


Asunto(s)
Secuestro de Carbono , Carbono , Biomasa , Carbono/análisis , China , Ecosistema , Bosques , Suelo , Árboles
8.
Ying Yong Sheng Tai Xue Bao ; 32(3): 1045-1053, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33754571

RESUMEN

Based on InVEST model, recreational opportunity spectrum, factor analysis, cold and hot spot analysis, SOFM neural network, relief degree of land surface (RDLS) methods, we evalua-ted six kinds of ecosystem service in Fuzhou City and analyzed the trade-offs and synergies among them, with the aim to clarify the dominant services and the spatial pattern of service bundles in different topographical regions. The results showed substantial spatial heterogeneity in different ecosystem services of Fuzhou City. Water yield, carbon sequestration, habitat quality, and recreational opportunities were totally high, whereas the supply of agricultural products and soil and water conservation were low and substantial differences. The interaction between water yield and cultural servi-ces were synergies, but trade-offs occurred among regulating service, supporting service and agricultural products service. There were spatial aggregations for both trade-offs and synergies. Ecosystem service bundles could be divided into suburban recreation bundle, water conservation bundle, agricultural products bundle, urban life bundle, and forest ecological conservation bundle. The composition of service bundles clusters was different under different RDLS, with obvious spatial heterogeneity.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Secuestro de Carbono , Ciudades , Suelo
9.
Sci Total Environ ; 769: 144341, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33736241

RESUMEN

Nature-based solutions (NbS) can address climate change, biodiversity loss, human well-being and their interactions in an integrated way. A major barrier to achieving this is the lack of comprehensiveness in current carbon accounting which has focused on flows rather than stocks of carbon and led to perverse outcomes. We propose a new comprehensive approach to carbon accounting based on the whole carbon cycle, covering both stocks and flows, and linking changes due to human activities with responses in the biosphere and atmosphere. We identify enhancements to accounting, namely; inclusion of all carbon reservoirs, changes in their condition and stability, disaggregated flows, and coverage of all land areas. This comprehensive approach recognises that both carbon stocks (as storage) and carbon flows (as sequestration) contribute to the ecosystem service of global climate regulation. In contrast, current ecosystem services measurement and accounting commonly use only carbon sequestration measured as net flows, while greenhouse gas inventories use flows from sources to sinks. This flow-based accounting has incentivised planting and maintaining young forests with high carbon uptake rates, resulting, perversely, in failing to reveal the greater mitigation benefit from protecting larger, more stable and resilient carbon stocks in natural forests. We demonstrate the benefits of carbon storage and sequestration for climate mitigation, in theory as ecosystem services within an ecosystem accounting framework, and in practice using field data that reveals differences in results between accounting for stocks or flows. Our proposed holistic and comprehensive carbon accounting makes transparent the benefits, trade-offs and shortcomings of NbS actions for climate mitigation and sustainability outcomes. Adopting this approach is imperative for revision of ecosystem accounting systems under the System of Environmental-Economic Accounting and contributing to evidence-based decision-making for international conventions on climate (UNFCCC), biodiversity (CBD) and sustainability (SDGs).


Asunto(s)
Carbono , Ecosistema , Ciclo del Carbono , Secuestro de Carbono , Cambio Climático , Conservación de los Recursos Naturales , Bosques , Humanos
10.
Nat Commun ; 12(1): 1785, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741981

RESUMEN

Tropical secondary forests sequester carbon up to 20 times faster than old-growth forests. This rate does not capture spatial regrowth patterns due to environmental and disturbance drivers. Here we quantify the influence of such drivers on the rate and spatial patterns of regrowth in the Brazilian Amazon using satellite data. Carbon sequestration rates of young secondary forests (<20 years) in the west are ~60% higher (3.0 ± 1.0 Mg C ha-1 yr-1) compared to those in the east (1.3 ± 0.3 Mg C ha-1 yr-1). Disturbances reduce regrowth rates by 8-55%. The 2017 secondary forest carbon stock, of 294 Tg C, could be 8% higher by avoiding fires and repeated deforestation. Maintaining the 2017 secondary forest area has the potential to accumulate ~19.0 Tg C yr-1 until 2030, contributing ~5.5% to Brazil's 2030 net emissions reduction target. Implementing legal mechanisms to protect and expand secondary forests whilst supporting old-growth conservation is, therefore, key to realising their potential as a nature-based climate solution.


Asunto(s)
Secuestro de Carbono , Carbono/metabolismo , Cambio Climático , Bosques , Clima Tropical , Algoritmos , Biomasa , Brasil , Conservación de los Recursos Naturales/métodos , Ecosistema , Fuego , Agricultura Forestal , Geografía , Modelos Teóricos , Imágenes Satelitales/métodos , Árboles/crecimiento & desarrollo , Árboles/metabolismo
11.
J Environ Manage ; 287: 112318, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33740746

RESUMEN

Soils as key component of terrestrial ecosystems are under increasing pressures. As an advance to current static assessments, we present a dynamic soil functions assessment (SFA) to evaluate the current and future state of soils regarding their nutrient storage, water regulation, productivity, habitat and carbon sequestration functions for the case-study region in the Lower Austrian Mostviertel. Carbon response functions simulating the development of regional soil organic carbon (SOC) stocks until 2100 are used to couple established indicator-based SFA methodology with two climate and three land use scenarios, i.e. land sparing (LSP), land sharing (LSH), and balanced land use (LBA). Results reveal a dominant impact of land use scenarios on soil functions compared to the impact from climate scenarios and highlight the close link between SOC development and the quality of investigated soil functions, i.e. soil functionality. The soil habitat and soil carbon sequestration functions on investigated agricultural land are positively affected by maintenance of grassland under LSH (20% of the case-study region), where SOC stocks show a steady and continuous increase. By 2100 however, total regional SOC stocks are higher under LSP compared to LSH or LBA, due to extensive afforestation. The presented approach may improve integrative decision-making in land use planning processes. It bridges superordinate goals of sustainable development, such as climate change mitigation, with land use actions taken at local or regional scales. The dynamic SFA broadens the debate on LSH and LSP and can reduce trade-offs between soil functions through land use planning processes.


Asunto(s)
Carbono , Suelo , Agricultura , Austria , Carbono/análisis , Secuestro de Carbono , Ecosistema
12.
Environ Sci Technol ; 55(8): 5180-5188, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33724824

RESUMEN

Incentivizing bioenergy crop production in locations with marginal soils, where low-input perennial crops can provide net carbon sequestration and economic benefits, will be crucial to building a successful bioeconomy. We developed an integrated assessment framework to compare switchgrass cultivation with corn-soybean rotations on the basis of production costs, revenues, and soil organic carbon (SOC) sequestration at a 100 m spatial resolution. We calculated profits (or losses) when marginal lands are converted from a corn-soy rotation to switchgrass across a range of farm gate biomass prices and payments for SOC sequestration in the State of Illinois, United States. The annual net SOC sequestration and switchgrass yields are estimated to range from 0.1 to 0.4 Mg ha-1 and 7.3 to 15.5 Mg dry matter ha-1, respectively, across the state. Without payments for SOC sequestration, only a small fraction of marginal corn-soybean land would achieve a 20% profit margin if converted to switchgrass, but $40-80 Mg-1 CO2e compensation could increase the economically viable area by 140-414%. With the compensation, switchgrass cultivation for 10 years on 1.6 million ha of marginal land in Illinois will produce biomass worth $1.6-2.9 billion (0.95-1.8 million Mg dry biomass) and mitigate 5-22 million Mg CO2e.


Asunto(s)
Secuestro de Carbono , Suelo , Agricultura , Carbono/análisis , Illinois
13.
Artículo en Inglés | MEDLINE | ID: mdl-33670002

RESUMEN

The natural mountain forests in northwest China are recognized as a substantial carbon pool and play an important role in local fragile ecosystems. This study used inventory data and detailed field measurements covering different forest age groups (young, middle-aged, near-mature, mature, old-growth forest), structure of forest (tree, herb, litter and soil layer) and trees (leaves, branches, trunks and root) to estimate biomass, carbon content ratio, carbon density and carbon storage in Altai forest ecosystems. The results showed that the average biomass of the Altai Mountains forest ecosystems was 126.67 t·hm-2, and the descending order of the value was tree layer (120.84 t·hm-2) > herb layer (4.22 t·hm-2) > litter layer (1.61 t·hm-2). Among the tree parts, trunks, roots, leaves and branches accounted for 50%, 22%, 16% and 12% of the total tree biomass, respectively. The average carbon content ratio was 0.49 (range: 0.41-0.52). The average carbon density of forest ecosystems was 205.72 t·hm-2, and the carbon storage of the forest ecosystems was 131.35 Tg (standard deviation: 31.01) inside study area. Soil had the highest carbon storage (65.98%), followed by tree (32.81%), herb (0.78%) and litter (0.43%) layers. Forest age has significant effect on biomass, carbon content ratio, carbon density and carbon storage. The carbon density of forest ecosystems in study area was spatially distributed higher in the south and lower in north, which is influenced by climate, topography, soil types and dominant tree species.


Asunto(s)
Carbono , Ecosistema , Biomasa , Carbono/análisis , Secuestro de Carbono , China , Bosques , Suelo , Árboles
14.
Environ Sci Technol ; 55(8): 4305-4313, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33764042

RESUMEN

Safe and cost-effective geologic carbon storage will require active CO2 reservoir management, including brine extraction to minimize subsurface pressure accumulation. While past simulation and experimental efforts have estimated brine extraction volumes, carbon management policies must also assess the energy or emissions penalties of managing and disposing of this brine. We estimate energy and CO2 emission penalties of extracted brine management on a per tonne of CO2 stored basis by spatially integrating CO2 emissions from U.S. coal-fired electric generating units, CO2 storage reservoirs, and brine salinity data sets under several carbon and water management scenarios. We estimate a median energy penalty of 4.4-35 kWh/tonne CO2 stored, suggesting that brine management will be the largest post capture and compression energy sink in the carbon storage process. These estimates of energy demand for brine management are useful for evaluating end-uses for treated brine, assessing the cost of CO2 storage at the reservoir level, and optimizing national CO2 transport and storage infrastructure.


Asunto(s)
Dióxido de Carbono , Carbono , Secuestro de Carbono , Sales (Química)
15.
Glob Chang Biol ; 27(9): 1721-1736, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33657680

RESUMEN

The global demand for beef is rapidly increasing (FAO, 2019), raising concern about climate change impacts (Clark et al., 2020; Leip et al., 2015; Springmann et al., 2018). Beef and dairy contribute over 70% of livestock greenhouse gas emissions (GHG), which collectively contribute ~6.3 Gt CO2 -eq/year (Gerber et al., 2013; Herrero et al., 2016) and account for 14%-18% of human GHG emissions (Friedlingstein et al., 2019; Gerber et al., 2013). The utility of beef GHG mitigation strategies, such as land-based carbon (C) sequestration and increased production efficiency, are actively debated (Garnett et al., 2017). We compiled 292 local comparisons of "improved" versus "conventional" beef production systems across global regions, assessing net GHG emission data from Life Cycle Assessment (LCA) studies. Our results indicate that net beef GHG emissions could be reduced substantially via changes in management. Overall, a 46 % reduction in net GHG emissions per unit of beef was achieved at sites using carbon (C) sequestration management strategies on grazed lands, and an 8% reduction in net GHGs was achieved at sites using growth efficiency strategies. However, net-zero emissions were only achieved in 2% of studies. Among regions, studies from Brazil had the greatest improvement, with management strategies for C sequestration and efficiency reducing beef GHG emissions by 57%. In the United States, C sequestration strategies reduced beef GHG emissions by over 100% (net-zero emissions) in a few grazing systems, whereas efficiency strategies were not successful at reducing GHGs, possibly because of high baseline efficiency in the region. This meta-analysis offers insight into pathways to substantially reduce beef production's global GHG emissions. Nonetheless, even if these improved land-based and efficiency management strategies could be fully applied globally, the trajectory of growth in beef demand will likely more than offset GHG emissions reductions and lead to further warming unless there is also reduced beef consumption.


Asunto(s)
Efecto Invernadero , Gases de Efecto Invernadero , Animales , Brasil , Secuestro de Carbono , Bovinos , Humanos , Estadios del Ciclo de Vida
16.
J Environ Manage ; 286: 112154, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609929

RESUMEN

Biochar has been recognised as a carbon dioxide removal (CDR) technology. Unlike other CDR technologies, biochar is expected to deliver various valuable effects in e.g. agriculture, animal husbandry, industrial processes, remediation activities and waste management. The diversity of biochar side effects to CDR makes the systematic environmental assessment of biochar projects challenging, and to date, there is no common framework for evaluating them. Our aim is to bridge the methodology gap for evaluating biochar systems from a life-cycle perspective. Using life cycle theory, actual biochar projects, and reviews of biochar research, we propose a general description of biochar systems, an overview of biochar effects, and an evaluation framework for biochar effects. The evaluation framework was applied to a case study, the Stockholm Biochar Project. In the framework, biochar effects are classified according to life cycle stage and life cycle effect type; and the biochar's end-of-life and the reference situations are made explicit. Three types of effects are easily included in life cycle theory: changes in biosphere exchanges, technosphere inputs, and technosphere outputs. For other effects, analysing the cause-effect chain may be helpful. Several biochar effects in agroecosystems can be modelled as future productivity increases against a reference situation. In practice, the complexity of agroecosystems can be bypassed by using empirical models. Existing biochar life cycle studies are often limited to carbon footprint calculations and quantify a limited amount of biochar effects, mainly carbon sequestration, energy displacements and fertiliser-related emissions. The methodological development in this study can be of benefit to the biochar and CDR research communities, as well as decision-makers in biochar practice and policy.


Asunto(s)
Carbón Orgánico , Suelo , Agricultura , Secuestro de Carbono
17.
J Environ Manage ; 286: 112160, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33611067

RESUMEN

Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface water. Moreover, a higher rate of decomposition than primary production (photosynthesis) may lead to a shift of their function from being a sink of carbon to a source. This review paper assesses the potential response of natural wetlands (peatlands) and constructed wetlands to climate change in terms of gas emission and nutrients release. In addition, the impact of key climatic factors such as temperature and water availability on wetlands has been reviewed. The authors identified the methodological gaps and weaknesses in the literature and then introduced a new framework for conducting a comprehensive mesocosm experiment to address the existing gaps in literature to support future climate change research on wetland ecosystems. In the future, higher temperatures resulting in drought might shift the role of both constructed wetland and peatland from a sink to a source of carbon. However, higher temperatures accompanied by more precipitation can promote photosynthesis to a degree that might exceed the respiration and maintain the carbon sink role of the wetland. There might be a critical water level at which the wetland can preserve most of its services. In order to find that level, a study of the key factors of climate change and their interactions using an appropriate experimental method is necessary. Some contradictory results of past experiments can be associated with different methodologies, designs, time periods, climates, and natural variability. Hence a long-term simulation of climate change for wetlands according to the proposed framework is recommended. This framework provides relatively more accurate and realistic simulations, valid comparative results, comprehensive understanding and supports coordination between researchers. This can help to find a sustainable management strategy for wetlands to be resilient to climate change.


Asunto(s)
Cambio Climático , Humedales , Secuestro de Carbono , Ecosistema , Hidrología
18.
Sci Total Environ ; 772: 145469, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33571772

RESUMEN

Phytoliths, silica structures derived from plant residues in silicon (Si)-accumulating plant species, have recently been recognized as a sink and source of nutrients and a hosting phase for carbon sequestration in soil. While the solubility of phytoliths in relation to their respective nature and solution chemistry has been intensively studied, the combined effects of CO2 and temperature, two highly variable parameters in soil, have not been fully understood. We hypothesized that changes in CO2 and temperature may affect the dissolution rate, thereby resizing the soil phytolith pool. Rice straw phytoliths were obtained from either open burning or controlled heating of straw from 300 to 900 °C and used to determine their batch incubation kinetics in a closed chamber at CO2 concentrations of 0 to 15% vol. and a temperature range of 20 to 50 °C for six days. The results revealed a contrasting effect in which temperature and CO2 were correspondingly found to accelerate or decelerate the dissolution rate of phytoliths. Under the most dissimilar conditions, i.e., 0% vol. CO2 and 50 °C and 15% vol. CO2 and 20 °C, the discrepancy in solubility was approximately six-fold, indicating a high vulnerability of phytoliths to CO2 and temperature changes. This finding also suggests that the soil phytolith pool can be diminished in the case of either increasing soil temperature or decreasing CO2 flux. Calculations based on these data revealed that the dissolution rate of phytoliths could be increased by an average of 4.5 to 7.3% for each 1 °C increase in temperature. This finding suggests a possible impact of current global warming on the global biogenic silica pool, and more insight into the relationship between this pool and climate change is, therefore, necessary to maintain the function of the phytolith phase in soil.


Asunto(s)
Dióxido de Carbono , Secuestro de Carbono , Dióxido de Carbono/análisis , Suelo , Solubilidad , Temperatura
19.
Water Sci Technol ; 83(4): 803-817, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33617488

RESUMEN

In the previous study, greenhouse gas CO2 was successfully used as the precipitator to realize its carbonation by calcium ions in seawater with the help of magnesium oxide. In this study, the reaction process was firstly analyzed by a proposed reaction mechanism, and then the dynamic simulation of the gas-liquid-solid system was carried out via kinetic Monte Carlo simulation. Based on the reaction mechanism, the continuous experimental study was realized in a bubble column. The effects of air flow rate, carbon dioxide flow rate and temperature on the effectiveness evaluation indexes of decalcification efficiency, total mass transfer coefficient and carbon sequestration rate were studied. Finally, a bonnet tower with a diameter of 1 m and a height of 8 m was built to carry out the pilot test. In the laboratory experiments, the calcium removal rate reached 94%, the carbon sequestration rate reached 63.6%, and pure micron calcium carbonate products were obtained. The decalcification rate reached 95% in the pilot test, which is consistent with the results of the laboratory experiment.


Asunto(s)
Dióxido de Carbono , Secuestro de Carbono , Carbonato de Calcio , Carbonatos , Agua de Mar
20.
J Environ Manage ; 285: 112135, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33588161

RESUMEN

The study was designed to quantify value and the spatial distribution of key ecosystem services such as wood production, habitat for biodiversity, carbon sequestration and air quality regulation in two areas: Eregli and Yesilkusak of Turkey. Wood production was quantified using forest inventory data and yield tables. Carbon storage was estimated based on the above - and below - ground biomass, deadwood and litter and soil. Habitat for species was characterized with a practical method based on the protection categories of stands. Vegetation cover in close proximity to the artificial surfaces and total health care cost avoided by the vegetation were used to quantify air quality regulation. Value transfer method was used in the valuation of ES in both areas. Average amount of wood production is quite low (5.7 m3/ha in Eregli and 6 m3/ha in Yesilkusak) compared to the overall average (72 m3/ha) in Turkey. The amount of carbon is largely low (64-100 tC/ha), indicating poor to medium capacity of the areas. The value of habitat for biodiversity is medium with some crucial habitats and target species. Both areas indicate low air quality regulation capacity. Total economic value of the key ecosystem services was estimated $438,128,571 in 2017 ($127,303,516 for Yesilkusak, $310,825,054 for Eregli). Composition and configuration of ecosystems determine the sustainable provision of ecosystem services. The potential economic value of ecosystems constitutes the basis for trade-off analysis in allocating best land use and utilization strategy. Developing enabling environment, accessing the best use of technologies and adopting best practice example for realizing sustainable forest management initiative is proposed to be the apparent strategy to enhance the role of ecosystem services in livelihood.


Asunto(s)
Ecosistema , Bosques , Biomasa , Carbono/análisis , Secuestro de Carbono , Conservación de los Recursos Naturales , Árboles , Turquia
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