Greenhouse Effect Research Articles

Forecasting the market value of power battery industry chain: A novel RRMIDAS-SVR model

The emergence of electric vehicles has contributed to mitigating air pollution and greenhouse effects caused by traditional fuel vehicles. The power battery industry chain, which is a primary component of electric vehicles, requires more attention to monitor its development status. This study proposes a novel method for forecasting the development status of the power battery industry chain by monitoring the market value index of all listed companies in the power battery industry. It proposes a new forecasting model, RRMIDAS-SVR, which outlines reverse-restricted mixed data sampling (RRMIDAS) into support vector regression (SVR) to end the data-driven challenges of mixed-frequency data and nonlinear relationships. We estimate the RRMIDAS-SVR model using a quadratic programming problem and mixed-frequency West Texas Intermediate crude oil futures prices, electric vehicle sales, and the consumer price index as predictors of the market value of all listed companies in the power battery industry chain. The experimental findings reveal that the RRMIDAS-SVR model outperforms the other models, as evidenced by its lower mean absolute error and root-mean-square error. This study contributes to understanding the development status of the power battery industry value chain by proposing and developing a new approach, RRMIDAS-SVR, to monitor the industry's development status that considers a multi-source information set. Moreover, this study provides strategic insights for stakeholders in the power battery industry.

Evaluation of RuBisCO gene expression in Caragana arborescens f. pyramidalis LAM. under drought conditions

Abstract At present, there is an increase in the concentration of CO2 in the atmosphere, which leads to significant climatic changes, especially in arid areas. Tree and shrub species provide fixation of atmospheric carbon dioxide, ensuring assimilation of inorganic carbon used in photosynthesis, as well as reducing the greenhouse effect. The enzyme Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) binds CO2 and triggers the Calvin cycle. The aim of the study was to evaluate the expression of the large subunit of the RuBisCO gene (RbcL) in Caragana arborescens f. pyramidalis LAM. and the in-house selected variety Caragana arborescens f. pyramidalis LAM. “Incomparable VNIALMI”, growing under drought conditions on the Kirov forestry (North of the Ergeninskaya Upland) with a characteristic arid climate. RNA was isolated from leaf blades collected at the end of fruiting. RbcL expression was evaluated by RT-qPCR using a universal primer pair selected by us. The study determined that the vital state in C. arborescens f. pyramidalis and C. arborescens f. pyramidalis ‘Incomparable VNIALMI’ was rated as good and that they were adapted to arid climate. Other analysis of RbcL expression showed lower values of amplification threshold cycles in C. arborescens f. pyramidalis LAM. “Incomparable VNIALMI”.

Anthropogenic activities have accelerated the restoration of carbon sequestration services in the upper Yellow River

Carbon sequestration services stemming from ecosystems facilitate the absorption of CO2 and mitigation of greenhouse effects. Thus, investigating the spatiotemporal changes of carbon sequestration services and their response patterns to human activities is essential in relation to achieving the strategic carbon peak and carbon neutrality (“double carbon”) goal in a region. In this study, the spatiotemporal carbon sequestration patterns in the upper reaches of the Yellow River from 1985 to 2020 were assessed based on measured sample points and spatial modeling combined with multi-source remote sensing data. Specifically, the impacts of human activities on the carbon sequestration services in the area were quantitatively analyzed. The results showed that, for the past 35 years, carbon sequestration in the upper reaches of the Yellow River ranged from 80.09 Tg to 98.48 Tg, with lower levels in the northeast and southwest, and higher ones in the northwest and southeast. From 1985 to 1998, carbon sequestration in the upper reaches of the Yellow River was mainly affected by the natural climate and showed a fluctuating upward trend. From 1998 to 2001, carbon sequestration declined sharply due to the influence of human activities and the natural climate, whereas it showed a significant increasing trend from 2001 to 2020, affected by the combined effects of ecological engineering and climate change. In 1998–2001, the degree of human influence was −5.92% to approximately −11.68%, and from 2001 to 2020, it was approximately 2.32% to 6.78%. This study shows that while human social development can negatively affect the carbon sequestration services of ecosystems, ecological engineering can accelerate its recovery, recovery trends and recovery endpoints are constrained by natural factors.

Efficient solar-driven: Photothermal catalytic reduction of atmospheric CO2 at the gas-solid interface by CuTCPP/MXene/TiO2

Directly capturing atmospheric CO2 and converting it into valuable fuel through photothermal synergy is an effective way to mitigate the greenhouse effect. This study developed a gas–solid interface photothermal catalytic system for atmospheric CO2 reduction, utilizing the innovative photothermal catalyst (Cu porphyrin) CuTCPP/MXene/TiO2. The catalyst demonstrated a photothermal catalytic performance of 124 μmol·g−1·h−1 for CO and 106 μmol·g−1·h−1 for CH4, significantly outperforming individual components. Density functional theory (DFT) results indicate that the enhanced catalytic performance is attributed to the internal electric field between the components, which significantly enhances carrier utilization. The introduction of CuTCPP reduces free energy of the photothermal catalytic reaction. Additionally, the local surface plasmon resonance (LSPR) effect and high-speed electron transfer properties of MXene further boost the catalytic reaction rate. This well-designed catalyst and catalytic system offer a simple method for capturing atmospheric CO2 and converting it in-situ through photothermal catalysis.

The influence of exhaust gas recirculation on combustion and emission characteristics of ammonia-diesel dual-fuel engines: Heat capacity, dilution and chemical effects

As the greenhouse effect intensifies, ammonia is garnering increasing attention as a carbon-free fuel. In the transport sector, ammonia-diesel dual-fuel (ADDF) engines are regarded as an effective means of reducing carbon emissions. The objective of this study is to investigate the combustion and emission optimization of an ADDF engine under high load conditions. To this end, an experimental optimization study of different start of diesel injection timing (SODI) and exhaust gas recirculation (EGR) rates was conducted at a load of 18 bar and an ammonia energy ratio of 80 %. The mechanism of heat capacity, dilution, and chemical effects of EGR was also revealed by numerical simulation based on the separated variables method. It was demonstrated that advancing SODI is effective in enhancing combustion efficiency. However, this approach is limited by the upper limit of in-cylinder pressure and results in higher nitrogen oxides (NOx) emissions, which can be mitigated by the EGR. The heat capacity effect of EGR increases the specific heat capacity and decreases the average temperature. The suppression of the combustion process leads to a reduction in thermal and fuel NOx, but an increase in nitrous oxide (N2O) emissions. The dilution effect of EGR results in insufficient oxygen, which decreases the heat release rate and combustion efficiency. Additionally, the NOx and N2O are significantly reduced. The chemical effect of EGR affects reactive groups and unburned components that accelerate heat release rate and increase accumulated heat release, resulting in significantly higher NOx. The comprehensive effect of EGR results in a decrease in N2O emissions and a significant reduction in thermal and fuel NOx. The EGR and further optimization of SODI enabled the ADDF engine to achieve a gross indicated thermal efficiency of 48.5 % with a load of 18 bar and an ammonia energy ratio of 80 %. In addition, NO emissions were reduced by 32.8 percent and greenhouse gas emissions by 63.3 percent.

Potential reduction of CO2 emissions which is the cause of greenhouse gases during COVID-19

Background: The implementation of education in tertiary institutions contributes significantly to greenhouse gas emissions, particularly carbon dioxide (CO2), which causes the greenhouse effect and global warming. The Intergovernmental Panel on Climate Change (IPCC) identifies transportation, energy supply, and industry as the primary sectors driving CO2 emissions over the past 30 years. However, the COVID-19 pandemic unexpectedly reduced CO2 emissions globally by up to 70% due to restricted activities. In 2020, the pandemic led countries, including Indonesia, to enforce Large-Scale Social Restrictions (PSBB) to curb virus spread, which significantly limited community mobility and vehicle use. Climate change, driven by greenhouse gas emissions, is a critical development challenge for Indonesia. Method: The study uses various calculation methods from journals and websites, incorporating expert opinions and the IPCC's method, to analyze emission reductions. Findings: The findings indicate that the COVID-19 pandemic and associated lockdowns reduced CO2 emissions due to decreased fuel consumption and mobility. Conclusion: This period highlights opportunities for strategies like low-carbon development to continue reducing emissions from vehicles. Novelty/Originality of this Study: This study provides a novel contribution by quantitatively assessing CO2 emission reductions during the COVID-19 lockdown, emphasizing the unique context of an unprecedented global event. It conducts a comprehensive literature review to integrate various CO2 calculation methods, particularly highlighting the sophisticated IPCC method, and offers a comparative analysis of emission reduction techniques.

A study on surface temperature of different materials

Excessive buildings took over green vegetation, which aggravated the greenhouse effect. If we use vegetation as roofs and exterior walls of buildings, the areas of plants will not reduce, and even the temperature around the building will decrease. Therefore, we planned to detect the surface temperature of different materials to provide evidence for ideal materials. We detected surface temperature of different materials with an infrared temperature gun (DELIXI, DM-5002). Detected materials included turf, suffruticosa plant, and soil under them, tile or concrete, wood, water with different depths of 1cm, 5cm, 10cm. We detected different materials under different weather conditions. The surface temperature of turf was significantly decreased compared with tile or concrete, wood (p<0.05). There was no significant difference between wood and tile/concrete temperature. Compared with tile/concrete or wood, the surface temperatures of water, turf, suffruticosa plant, and soil under plant significantly decreased (p<0.05). There was no significant difference of temperature between water with different depths. There was no significant difference in temperature between turf, suffruticosa plant, and the soil under them, too. The surface temperatures of turf, suffruticosa plant, and water were significantly lower than those of tile/concrete and wood we used as raw materials of buildings. Plants can be recommended as new materials covering roofs and exterior walls to decrease temperature around buildings in summer.

Emisi Metana (CH4) pada Beberapa Metode Pengelolaan Limbah Sawah di Kecamatan Anjir Pasar Kabupaten Barito Kuala

Paddy fields for all of Indonesia are 8.1 million ha, about 43% are in Java and about 57% are outside Java. Paddy fields are part of the wetlands. Paddy fields control the global climate through the gases they produce and have a greenhouse effect. One of the greenhouse gases is methane, therefore the purpose of this study was to determine the effect of rice field waste management on methane emissions and the population of methanogenic microorganisms. The research method used is one-factor Completely Randomized Design (RAL). The factor tested was the method of managing rice waste before planting rice with five treatments namely: A = Rice field waste was slashed and then lifted into the mound after a few days of being returned to the field; B = Rice field waste is carried out management slashed, rolled up, reversed, and stretched; C = Rice field waste is slashed, planted with traces and then slashed again after the trace is transferred to land outside the research plot; D = Rice field waste sprayed with herbicide 2 times; E = Ricefield waste sprayed with herbicide 1 time and then soil in the tractor. Each treatment was repeated four times so 20 units of the experimental. CH4 gas retrieval used the hood method while the microorganism population used the MPN (most probable Number) method. The results showed that the rice field waste management method had an effect on methane emissions and populations of methanogen microorganisms in the planting and vegetative phases, while the generative phase had no effect.

Environmental, energy, and economic assessment of Jatropha curcas L. biodiesel production in China

Developing non-grain forestry woody fuel industries such as Jatropha curcas L. (JCL) aligns with the national conditions of countries with food shortages and large populations, such as some countries in Africa and Asia, and is an ideal alternative to replace fossil fuels. Determining appropriate planting densities suitable for different regions is one of the most critical practices for agriculture and forestry to achieve high yields and sustainability. This study conducted a life cycle assessment (LCA) of the JCL biodiesel's environmental impact, energy balance, and economic analysis (3E) of two densities and three of the most suitable planting regions in China. Findings reveal that the density of 2500 plants/ha had a better 3E performance than 1600 plants/ha, and Yunnan province outperformed Guizhou province and Sichuan province. JCL biodiesel effectively mitigates the greenhouse effect (1141.14–1936.59 kg CO2 eq/t) compared to conventional fossil diesel in different cases. Key factors influencing environmental performance include seed yield, urea applied during cultivation, methanol for biodiesel conversion, and electricity for irrigation. The Net Energy Balance (NEB) and Net Energy Ratio (NER) demonstrate the superior energy efficiency of JCL biodiesel over fossil diesel. The cost of producing JCL biodiesel decreased with the maturation of the trees, with water use and labor salary accounting for over 80% due to the necessity of the cultivation stage. Although the Financial Net Present Value (FNPV) was negative when considering only JCL biodiesel, it became positive (12111.64–27342.44 CNY) with the inclusion of by-products (glycerine, press-cake, and shells) in high-density cases. Our findings suggest that JCL biodiesel with appropriate density can serve as a sustainable biofuel alternative, replacing a portion of the fossil diesel currently on the market and significantly contributing to climate change mitigation and nonrenewable energy conservation.

G-C3N4-Based Photocatalytic Materials for Converting CO2 Into Energy: A Review.

Environmental pollution management and renewable energy development are humanity's biggest issues in the 21st century. The rise in atmospheric CO2, which has surpassed 400 parts per million, has stimulated research on CO2 reduction and conversion methods. Presently, photocatalytic conversion of CO2 to valuable hydrocarbons enables the transformation of solar energy into chemical energy and offers a novel avenue for energy conversion while regulating the greenhouse effect. This is an ideal strategy for simultaneously addressing environmental issues and the energy crisis. Photocatalysts are essential to photocatalytic processes. Photocatalyst is the core of photocatalytic technology, and graphite carbon nitride (g-C3N4) has attracted much attention because of its nonmetallic characteristics, and it has the characteristics of low cost, tunable electronic structure, easy manufacture and strong reducibility. However, its activity is not only affected by external reaction conditions, but also by the band gap structure, physical and chemical stability, surface morphology and specific surface area of the photocatalyst it. In this paper, the application progress of g-C3N4-based photocatalytic materials in CO2 reduction is reviewed, and the modification strategies of g-C3N4-based catalysts to obtain better catalytic efficiency and selectivity in CO2 photocatalytic reduction are summarized, and the future development of this material is prospected.

Integrated models for carbon emission prediction: Combining epidemiology models and statistical forecasting

The topic of our article is Integrated Models for Carbon Emission Prediction: Combining Epidemiology Models and Statistical Forecasting. In this work, we need to combine various epidemiological models from different perspectives, including evolution, application and statistics, to simulate and predict carbon emissions and obtain the results we need. The following content is about the results we have obtained, and its significance lies in predicting and analyzing when and how much carbon emissions will peak in various possible scenarios. Predict the most likely peak time and peak volume from a regional and industry perspective, providing decision-making basis and reference for scientifically and reasonably formulating emission reduction policies. Also, some application in real life of the integrated models is shown in this paper. In addition, the limitations and challenges we face are provided in the article, we are able to consider how to improve the prediction by analyzing these limitations. This article includes a case study about energy which allows us to better have a more comprehensive and vivid image and understanding of the models. All the actions in this work will be meaningful in our life because carbon play an important role in environment like greenhouse effect and biological carbon cycle.

Investigation on methane hydrate formation behaviors in deep-sea methane seepage environments

Deep-sea cold seep is a natural phenomenon where methane leaks from the sea floor. Methane can be partially conversed through physical, chemical, and biological processes, but the excess methane that remains uncaptured escapes into the atmosphere and contributes to the greenhouse effect. Physical carbon sequestration via hydrate formation is a fast and high-energy density type of carbon sequestration; however, it has been largely overlooked. This study investigated hydrate formation in authigenic carbonate rocks through deep-sea geological surveys in cold seeps in the South China Sea. Investigations have shown that authigenic carbonate rocks can sequester carbon by blocking the methane plume from the seepage vents. This perspective provides a new physical carbon sequestration mode of carbonate rocks by observing the artificial collection of methane plumes in deep-sea seepage areas. The mode was simplified into two steps including the formation of a thin layer of planar hydrate film on carbonate rocks and a thick layer of hydrate through the stacking of bubbles under the thin film. Salinity, a key distinction between seawater and freshwater, was further investigated for its impact on the carbon sequestration mechanism. Results showed that saline ions in seawater had little impact on the thickening rate of the planar hydrate film but reduced the lateral growth rate of hydrates on the bubble by 60%. This reduction in the lateral growth rate greatly facilitated the three-dimensional growth, increased the hydrate thickness on the bubble, and improved the carbon sequestration efficiency. Hydrate formation on the exposed carbonate rock can effectively impede methane plume migration into upper water and atmosphere, mitigate the greenhouse effect, and present a promising strategy for carbon sequestration in deep-sea methane seepage areas.

Application of Biomass Energy Monitoring Based on Renewable Energy Supply in Sports

Biomass energy is an ideal form of clean, renewable energy, characterized by its wide availability, low cost, strong renewability, and minimal pollution. The development and utilization of biomass energy are crucial for mitigating greenhouse effects, reducing air pollution, and alleviating energy pressure. Multi-functional biomass energy monitoring equipment and integrated systems have received extensive attention and are flourishing. This integrated design demonstrates a higher degree of integration, overall unity, diversification, and intelligence, which helps overcome the current developmental challenges of single-functionality and system isolation. One of the most representative designs of these integrated devices is the multi-energy conversion and utilization system, which efficiently converts low-grade energy into high-grade energy and provides various conversion pathways within a single system. This supplies ample energy for daily life and enables its full application in sports. By integrating self-powered wearable technology, this paper explores the use of a wearable sensor composed of KAP composite polyacrylamide/polyacrylic acid hydrogel (PAAH), namely KAP PAAH. The strain-voltage response and real-time sensing provided by KAP PAAH facilitate an electrically driven, self-powered integrated wearable sensor for human joint health monitoring. Additionally, this approach maximizes the residual value of biomass waste, highlighting its potential and high economic value for future practical applications. Specifically, the optimized design ensures reliable and continuous health monitoring during various sports activities, thus aligning with the broader environmental benefits of biomass energy.

Research on Student Management Platform Based on Big Data Under Low-Carbon Environment

This paper makes a comprehensive investigation on the development and implementation of low-carbon student management platform in educational institutions. The platform adopts advanced information technology, including cloud computing and big data analysis, aiming at solving urgent environmental problems by analyzing the dynamic learning data and daily behavior data of college students. The implementation of the platform has greatly reduced carbon emissions, especially greenhouse effect variables and dormitory electricity consumption. The observed impact highlights the effectiveness of using academic management platform to promote carbon emission reduction. However, this study acknowledges the existing limitations and predicts the long-term challenges, and emphasizes the need for continuous innovation and research in the intersection of artificial intelligence and environmental sustainable development. Generally speaking, the development and deployment of low-carbon student management platform is a key step to promote the sustainable development of educational environment.

Develop a novel and multifunctional soy protein adhesive constructed by rosin acid emulsion and TiO2 organic-inorganic hybrid structure

Soy protein adhesives (SPI) exhibit broad prospects in substituting aldehyde-based resin due to the economic and environmental-friendly characteristics, but still face a challenge because of the dissatisfied bonding strength and terrible water resistance. Herein, prompted by organic-inorganic hierarchy, a multifunctional and novel soy protein adhesive (SPI-RAE-TiO2) consisting of rosin acid emulsion (RAE) and TiO2 nanoparticles (TiO2) were proposed. In comparison with original SPI, the dry and wet shear strengths of modified adhesive reached 2.01 and 1.21 MPa, respectively, which were increased by 130 % and 200 %. Furthermore, SPI-6RAE-0.5TiO2 was selected as the best proportion via the method of response surface methodology (RSM). What's more, SPI-6RAE-0.5TiO2 adhesive demonstrated prominent coating performance in both dry and wet surface conditions. Meanwhile, SPI-6RAE-0.5TiO2 adhesive possessed excellent mildew resistance and antibacterial ability with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), reflecting the antibacterial rates 97.71 % and 98.16 %, respectively. In addition, SPI-6RAE-0.5TiO2 adhesive also exhibited the outstanding green features such as the reduction of formaldehyde pollution and greenhouse effect through Life Cycle Assessment (LCA). Thus, this work provided a novel and functional approach to design multifunctional, superior-property and low-carbon footprint soy protein adhesive.

Multiproxy faunal analysis of the middle – upper Eocene deposits in the Fayum area, Egypt: Insights into sequence stratigraphy, trophic conditions, and oxygenation

The Eocene epoch experienced significant fluctuations in climate, ranging from intense greenhouse warming to icehouse cooling, which profoundly impacted the global depositional systems. The middle – upper Eocene deposits in Garet Gehannam, Fayum area, Egypt, present an exciting opportunity to explore paleoenvironmental dynamics using a multiproxy dataset of calcareous nannofossils, benthic foraminifera, ostracods, and molluscan assemblages. Calcareous nannofossil biostratigraphy constrained the studied sequence to the NP17 and NP-19-20 zones. Furthermore, three 3rd-order depositional sequences, BAR.SQ.1, BAR.SQ.2, and PR.SQ.3 were identified. The BAR.SQ.1 sequence encompasses the Gehannam Formation, with a transgressive systems tract (TST) and a highstand systems tract (HST). The BAR.SQ.2 sequence corresponds to the lower Birket Qarun Formation and exhibits a TST/HST pattern. The PR.SQ.3 sequence, however, consists solely of a TST spanning the upper Birket Qarun and Qasr El Sagha formations. The main trend of our multiproxy-based sea level curve shows an overall stepped Tethyan sea level regression within the 2nd-order cycle. This regression is characterized by a transition from outer neritic to inner settings, interrupted by two minor 3rd-order transgressive pulses. This sea level trend was likely driven by global eustatic changes and regional tectonic uplift related to the final collisional phase between Africa/Arabia and Eurasia, which led to the closure of the Neotethys Ocean. Multiproxy faunal analysis reveals a pronounced upsection shift from low-oxic and mesotrophic conditions to well-ventilated, oligotrophic settings tracking long-term sea level fall. The lowering of the sea level may have expanded aerobic ventilation windows on the continental shelf while potentially reducing nutrient influx. Our multiproxy sequence stratigraphic and paleoenvironmental analysis provides insights into the complex interplay of tectonic, eustatic, and climatic influences on the region during the middle – late Eocene episode along the southern Tethyan margin.

A Study on the Efficient Degradation of Sulfur Hexafluoride by Pulsed Dielectric Barrier Discharge Synergistic Active Gas

SF6 is a strong greenhouse effect gas, which is widely used in high-voltage electrical equipment such as circuit breakers and high-voltage switchgear because of its excellent insulation performance and arc extinguishing ability. In recent years, the use and emission of SF6 have been rising, and with the proposal of the dual carbon strategic goal, its harmless degradation has become an urgent problem to be solved. In this paper, SF6 was degraded by pulsed DBD plasma technology and O2. Studies have shown that the addition of O2 can effectively promote the degradation of SF6. With the increase in the added O2 content, the DRE and EY of SF6 first increased and then decreased. Under the conditions of the input power of 50 W, SF6 concentration of 2%, and gas flow rate of 50 mL/min, the reaction system obtained the highest DRE and EY of 58.40% and 5.24 g/kWh when the O2 content was 1%, respectively. In the SF6/Ar/O2/H2O system, the addition of H2O could improve the product selectivity of SO2F2, and when the O2 concentration was 1%, the highest selectivity of SO2F2 was 48.96%, and the concentration was 8006.76 ppm. The addition of O2 inhibited the production of SO2, and with the addition of the O2 system, SO2F2 and SOF4 were the main components of degradation products; however, there were also SOF2, SO2, SiF4, SF4, etc. In this paper, the decomposition path of O2 under SF6 was analyzed in detail according to infrared spectroscopy and decomposition products.

Dual nanoparticles with rich Ni–CeO2 interfaces for efficient photothermal catalytic CO2 reduction by CH4

Reducing CO2 by CH4 (CRM) is of great significance for alleviating greenhouse effects and fuel shortages. However, the high energy consumption and low yield of fuel, as well as the deactivation of Ni based catalysts constrained its development. Herein, a novel Ni–CeO2/Al2O3 catalyst for photothermal catalytic CRM merely upon focused light irradiation was reported. Very high yield of H2 and CO (80.2 and 96.3 mmol min−1 g−1) and excellent catalytic durability were achieved. The results of UV-VIS-IR diffuse reflectance spectra and experimental test indicate that high yield of H2 and CO originates from efficient photothermal conversion and the molecular activation effect of light. More importantly, Ni–CeO2/Al2O3 exhibits better carbon deposition resistance than Ni/Al2O3. The structural characterization and experimental evidences reveal that the active lattice oxygen in CeO2 nanoparticles can be transferred to Ni nanoparticles via Ni–CeO2 interface to accelerate carbon oxidation and form oxygen vacancies. The formed oxygen vacancies can re-adsorb and activate CO2 to form new active lattice oxygen.

Editorial: Advances in Mineral Carbonation

Mineral carbonation stands out as a prominent technology aimed at reducing atmospheric CO2 emissions, a major contributor to the greenhouse effect, through a variety of processes [...]

Identifying a sustainable rice-based cropping system via on-farm evaluation of grain yield, carbon sequestration capacity and carbon footprints in Central China

ContextRice-based cropping system is a major anthropogenic source of direct greenhouse gases (GHG) emissions, agricultural inputs also produces numerous indirect GHG emissions and environmental problems. Identification of rice cropping systems with lower GHG emissions and higher grain yields is of great significance to ensure food security while minimizing agricultural carbon footprint (CF). ObjectiveThis study aimed to identify the optimal rice-based cropping system with lower greenhouse effects and comparable annual yield in central China. MethodsUsed life cycle assessment, a two-year field experiment was performed to evaluate the direct and indirect GHG emissions, CF, and carbon sequestration capacity in the six rice-based cropping systems widely used in central China, which consisted of fallow-early rice-late rice, rapeseed-early rice-late rice, fallow-ratoon rice, rapeseed-ratoon rice (RRaR), fallow-middle rice, and rapeseed-middle rice. ResultsThe results showed that compared with the three systems with fallow season, the three systems with rapeseed had lower annual CH4 emissions. The two systems with ratoon rice had lower annual indirect and direct GHG emissions than the two systems with double rice. The three systems with rapeseed had higher annual biomass, grain yields, and fixed carbon in biomass and significantly lower CF than the three systems with fallow season, and RRaR had the highest value of fixed carbon in biomass. The systems with ratoon rice had lower average CF than those systems with double rice. CH4 emissions from paddy fields were the primary source of total annual GHG and the main component of CF. Compared with the three systems with fallow season, the three systems with rapeseed had significantly higher annual carbon sequestration capacity based on net ecosystem production (NEP). Ratoon rice systems had higher average NEP than double- and middle-rice systems. RRaR had the lowest CF per unit yield and highest NEP among all the six systems. ConclusionsThe results indicated that appropriate rice-based cropping systems may alleviate the greenhouse effect via reducing GHG emissions and enhancing paddy NEP, RRaR could achieve relatively higher annual grain yield and carbon sequestration capacity as well as lower CF. SignificanceThis study highlight conversion of double rice and middle rice systems to RRaR may help improve grain yield and mitigate greenhouse effect. The findings may provide a theoretical basis for selection of sustainable development of rice based cropping systems in central China.