Net Carbon Emissions Research Articles

Optimizing Direct Air Capture Solvents to Minimize Energy Consumption of CO2 Release in a Carbonate Electrolyzer

Addressing climate change by carbon management is critical to achieving the goal of net zero carbon emissions by 2050. In this work, we examined the electrochemically-driven recovery of CO2 during alkaline solvent regeneration for solvent-based direct air capture. A mathematical model was developed by incorporating carbonate chemistry with water electrolysis to predict the energy consumption per unit of CO2 released. The predicted results were consistent with the experimental data, in which the experimental work was achieved by characterizing alkalinity and carbon loading values of solvent collected from a flow carbonate electrolyzer. Through this study, we learned that minimizing the energy expended on CO2 release can be achieved by using an anolyte with a lower alkalinity, increasing the electric charge input to the electrolyzer, and reducing the ohmic resistance of the electrolyzer. Furthermore, using a supporting electrolyte, e.g., Na2SO4 in the present work, effectively compensates for the higher ohmic resistance from using an anolyte with a lower alkalinity.

The effect of methylene blue on stearic acid-aged quartz/CO2/brine wettability: Implications for CO2 geo-storage

Carbon dioxide sequestration in geological formations has been proposed as a promising solution to reach net zero carbon emissions but the success of underground CO2 storage in sandstone formations depends on the brine/CO2 wettability of sandstone. Research evidence showed that natural geological formation is hydrophobic even in the presence of minute concentration of inherent organic acids. This study investigates the effect of methylene blue (MB) on CO2 wettability of organic-acid contaminated quartz through the tilted plate contact angle measurement method. Pure quartz substrates were aged in a stearic acid/n-decane solution for one week and subsequently modified with different concentrations of MB (ranging from 10 to 100 mg/L) at a temperature of 60 °C. Advancing (θa) and receding (θr) contact angles were measured under varying conditions of temperature (25 °C and 50 °C), pressure (ranging from 10 to 20 MPa), and salinity (0–0.3 M). The experimental results indicate that pure quartz, when aged in a stearic acid solution, becomes CO2-wet at all temperature, pressure, and salinity conditions. However, at any physio-thermal condition, the wettability of the quartz surfaces was reversed when treated with different concentrations of MB, transitioning to a water-wet state. The findings of this research demonstrate the potential of MB to modify the wetting behaviour of quartz surfaces and enhance CO2 residual trapping in sandstone formations.

Potential of solid recovered fuel production from autoclave treated healthcare waste in Sultanate of Oman

ABSTRACT Economic growth has a potential impact on waste generation worldwide. Growing recognition for resources recovery from waste including production of a clean energy has led to the development of standards for, and the generation of, Solid Recovered Fuel (SRF). SRF, according to BS EN ISO 21640 is a fuel prepared from nonhazardous/treated waste to be utilized for energy recovery in incineration or co-incineration plants which meets the classification and specification. The amount of combustible fractions (i.e., plastic, textile and paper) that are present in Healthcare Waste (HCW) and Municipal Solid Waste (MSW) provides an opportunity for SRF production. HCW is defined as clinical waste generated from healthcare facilities. Limited efforts in utilizing treated HCW in production of SRF were noted, despite the fact that high content of combustible fractions, hence the novelty of this research. This research addresses the opportunities of utilizing autoclaved HCW as an alternate fuel; through a detailed chemical and physical analysis of autoclaved HCW collected from the Sultanate of Oman hospital and healthcare facilities. Furthermore, this study examines the possible uses of such materials instead of landfilling. The utilization of treated HCW as an alternative fuel is not only saving the land space, but also reduces the carbon emissions originating from landfilling. This in fact would also support the government in achieving its aspiring goal of the net zero carbon emissions by 2050 through better utilization of these materials in production of SRF as an alternative to fossil fuel combustion. The study revealed that autoclaved HCW appears to have a high quality SRF and is classified as (NCV 4, Cl 3); which complies with the potential end users’ specifications. It is estimated that the combined energy output from MSW and HCW combustible fractions could cover about 12.75% of the energy requirements for Oman cement factories. Implications: The results confirm the viability of using autoclave (HCW) as an alternative fuel due to its high thermal energy content. Based on mean Net Calorific Value (NCV) of analyzed HCW that is found around 14 (MJ/Kg (ar)), and the mean Cl level (i.e., 0.814 ± 0.213% (d)); the SRF is classified as (NCV4, Cl 3). This grade is found to be well within the end users accepted range. This opens up the opportunity for creating a market demand for HCW that not only it could boost its recovery, but it could also unlock the value that can generates.

Pathway to net zero: Reviewing sustainable aviation fuels, environmental impacts and pricing

Supporting the pathway to net zero carbon emissions in the aviation industry, sustainable aviation fuels (SAF) will contribute to a large extent to reduce net CO2 emissions in the next decades to deliver on climate targets. For this reason, the large-scale uptake of SAFs in aviation is on top of the agenda of regulatory policy. However, challenges remain for building the respective infrastructure and supply chains at the appropriate scale to produce and distribute SAF at a reasonable cost. Currently, only one percent of fuels consumed by airlines in Europe are blended with sustainable aviation fuels. The paper examines current SAF production pathways, environmental benefits, and estimated fuel prices from the state-of-the art literature. Further, regulatory policies established by governments, regulatory agencies and industry associations are examined, regarding blending mandates in different regional markets. The authors conclude with the statistical analysis of minimum selling prices for different types of SAF, and discuss their respective availability.

Land-use simulation for synergistic pollution and carbon reduction: Scenario analysis and policy implications

Simulations of sustainable land use and management are required to achieve targets to reduce pollution and carbon emissions. Limited research has been conducted on synergistic pollution and carbon reduction (SPCR) in land-use simulations. This study proposed a framework for land-use simulation focused on SPCR. The non-dominated sorting genetic algorithm (NSGA-Ⅱ) and the entropy weight-based technique for order of preference by similarity to an ideal solution (TOPSIS) were used to optimize the land-use structure according to minimum net carbon, nitrogen, and phosphorus emissions. The cellular automata (CA) Markov model was then utilized to simulate the land-use spatial pattern according to the optimal conditions. The proposed framework was applied to the Dongjiang River Basin, South China, and three other scenarios (natural development (ND), carbon minimization (CM), and pollution minimization (PM)) were designed to validate the effectiveness of pollution and carbon emissions reduction under the SPCR scenario. The land-use structure and the pollution and carbon emissions in the scenarios were compared. The results showed the following. (1) The proportions of cultivated land, woodland, grassland, water, and construction land In the SPCR scenario accounted for 14%, 72%, 4%, 3%, and 7% of the total area, respectively. The carbon, nitrogen, and phosphorus emissions were 42.4%, 6.6%, and 7.8% lower, respectively, in the SPCR scenario than in the ND scenario, demonstrating the advantages of simultaneous pollution and carbon reduction. (2) The kappa coefficient of the CA-Markov model was 0.8729, indicating high simulation accuracy. (3) The simulated land-use spatial patterns exhibited low spatial heterogeneity under the CM, PM, and SPCR scenarios. However, there were significant disparities between the ND and SPCR scenarios. The cultivated and construction land areas were significantly smaller in the SPCR scenario than in the ND scenario. In contrast, the woodland and grassland areas were larger, with most differences in the central and southwestern regions of the Dongjiang River Basin. The results of the current study can be used to formulate effective land use policies and strategies in the Dongjiang Basin and similar areas to achieve the Coupling coordination between pollution reduction and carbon reduction. Policy recommendations include increasing the proportion of woodland and grassland, implementing reasonable constraints on expanding cultivated and construction lands, and establishing farmland red lines to promote synergistic pollution and carbon reduction.

Co-benefits for net carbon emissions and rice yields through improved management of organic nitrogen and water.

Returning organic nutrient sources (for example, straw and manure) to rice fields is inevitable for coupling crop-livestock production. However, an accurate estimate of net carbon (C) emissions and strategies to mitigate the abundant methane (CH4) emission from rice fields supplied with organic sources remain unclear. Here, using machine learning and a global dataset, we scaled the field findings up to worldwide rice fields to reconcile rice yields and net C emissions. An optimal organic nitrogen (N) management was developed considering total N input, type of organic N source and organic N proportion. A combination of optimal organic N management with intermittent flooding achieved a 21% reduction in net global warming potential and a 9% rise in global rice production compared with the business-as-usual scenario. Our study provides a solution for recycling organic N sources towards a more productive, carbon-neutral and sustainable rice-livestock production system on a global scale.

Analysis of the evolution and drivers of carbon inequality based on a human well-being equity perspective

Regional development imbalances lead to the geographic separation of producers and consumers in interregional trade, thus resulting in an unequal distribution of carbon emissions (CE) and human well-being (HWB). Few studies have analyzed the long-term dynamic evolution and driving factors of interregional carbon inequality from the perspective of HWB equity. This study calculates the changes in embodied CE and HWB and their interregional flows and changes in carbon inequality in 2007, 2012, and 2017 using a multiregional input‒output (MRIO) model, and analyzes the drivers of interregional CE/HWB transfer, and then makes policy implications. The results indicate that carbon inequality in China shows a worsening trend because of the mismatch between the change in CE transfers in carbon-intensive sectors and the change in HWB transfers in economic and social capital. At the national level, CE intensity, HWB intensity, production structure, and per capita consumption have the most significant effects on embodied CE and embodied HWB. The direction of the factor drivers affecting interregional net carbon emissions (NCE) and net human well-being (NWB) transfer depends largely on the resource endowment and the extent of the effects of the different drivers and development status of two regions. This study provides a new perspective for analyzing the evolution of carbon inequality in China and provides important insights for reducing carbon inequality and realizing carbon equity.

Research Progress in Facility Agriculture and Lighting by Bibliometric Analysis Based on CiteSpace

Given the pressures of internation-al market competition, the dual constraints of domestic resources and the environment, and the uncertainties posed by climate change, bolstering agricultural infra-structure construction is a realistic demand and a crucial approach for implementing emerging grain security strat-egies, particularly in developing countries. Facility agriculture is characterized as a modern agricultural production mode that improves or creates favorable environmental conditions within a specific locality. With the rapid expansion of large-scale facility agriculture, there has been an increased demand for various types of energy, including electricity, gas, cold, and heat. Agricultural lighting equipment used in facility agriculture is a modern agricultural technique that applies engineering technology to regulate light supplementation in the production process. Facility lighting offers several advantages over traditional methods, such as higher photovoltaic conversion efficiency, adjustable spectrum, high photosynthetic efficiency, energy efficiency, environmental friendliness, long lifespan, monochromatic light, cold light source, and compact size. Promoting national food security, carbon neutrality, returning farmland to forests, and implementing low-carbon green agricultural policies all contribute to the favorable use of facility agriculture lighting. This study aims to provide a systematic summary of the relevant research conducted in the past decade using Citespace software. The advantage of facility agriculture for carbon sequestration capacity can effectively reduce net carbon emissions from facility agricultural production activities. In addition, the combination of agriculture and the Internet of Things can effectively improve agricultural production efficiency and economic returns. Combining artificial intelligence and other technologies with facility agriculture engineering, based on multi-source data fusion, intelligent early warning for facility agriculture energy internet can be used to prevent agricultural meteorological disasters. More importantly, it helps maintain global food security, eliminate hunger, and reduce economic inequality. The findings of this study will contribute to a deeper understanding of agricultural lighting equipment, serving as a new theoretical foundation for achieving agricultural emission reduction targets and promoting agricultural technical cooperation.

Unequal transfer and its policy implications of carbon emissions and economic benefits embodied among Central Plains urban agglomeration

Tracing the carbon emissions and economic benefits embodied in trade is crucial for the equitable allocation of mitigation responsibilities, particularly among cities in China, where studies on this topic are lacking. Therefore, this study selected the Central Plains Urban Agglomeration (CPUA) as a representative region. It compiled carbon emissions inventories following the 2006 IPCC guidelines and employed the multi-regional input-output model to investigate the trade-attributed embodied carbon emissions and value-added. Additionally, it estimated the unequal transfers of these emissions and value-added by introducing the City Carbon Emissions Inequality index (CCEI). The results indicate that the CPUA received net carbon emissions of 454.99 and 330.95 Mt. from outside regions from 2012 to 2017. Nearly half of the territorial carbon emissions were driven by the consumption of other cities, and Zhengzhou and its surrounding cities transferred the most carbon emissions to the outer-ring cities by consuming the primary products produced in these cities. The construction sector was the largest exporter of both embodied emissions and economic benefits, while the energy and service industries were the largest importers of carbon emissions and economic benefits. Such imbalanced transfers contributed to carbon inequality, with the CCEI mean increasing from 0.31 to 0.38 for the exacerbation of intercity imbalances in development. Significant carbon inequality occurred between Zhengzhou and its upstream cities, e.g., Luoyang and Shangqiu, and among some neighboring cities, e.g., Yuncheng-Jincheng and Luoyang-Jiyuan. Our findings provide evidence of a need for compensation mechanisms and collaborative strategies for carbon mitigation in the urban agglomeration.

Analyzing the un-accounted gas causes in Indonesian household gas networks using text analytics

The development and growth process of domestic gas network in Indonesia is one of the Government's efforts towards National Energy Transformation or Zero Net Carbon Emissions by 2060. In its development, a number of challenges have been found to be addressed by the parties concerned. One of the major challenges faced in the development of jargas is the presence of unaccounted gas or gas losses, which is an unknown amount of gas, such as, for example, the value of un-acccounted gaseous gas in 2022 in a region reaches an average of -24,55%. The size of the UAG (Un-Accounted Gas) value needs to be known by the parties, so research is carried out using operational data such as a monthly report containing free text with the method of text analytics. Text analytics is used to perform Analysis to find out the factors causing the occurrence of value of UAG in Jargas. The analysis uses a number of Phyton-supported tools, including Anaconda, and Power BI. The data analysis uses 3,584 word strings, with 42 UAG cause variables, then extracted into 60 Tokens or keywords, then performed the analysis on 52 unique tokens, then focused on 19 main tokens. The results of the analysis showed that -24,55% of UAG causes are due to leakage (15,56%), third-party activity (3.52%), un-registered thieves (2,22%), gas-in activity (1,99%), and accuracy of measuring instruments (1,42%).

Carbon sequestration and credit potential of gamhar (Gmelina arborea Roxb.) based agroforestry system for zero carbon emission of India

The agroforestry system is the best option to achieve the net zero carbon emissions target for India. Keeping this view, carbon sequestration and credit potential of gamhar based agroforestry system has been assessed. The experiment was carried out in randomized block design in seven different treatments with five replications. Gamhar tree biomass accumulation was higher in gamhar based agroforestry system compared to sole gamhar. Among different tree components, stem contributed a maximum to total gamhar tree biomass followed by roots, leaves and branches. The average contributions of stems, roots, leaves and branches in total tree biomass in two annual cycles (2016–17 and 2017–18) varied between 50 and 60, 19.8 and 20, 19.2 and 20, and 10.7 and 12.7 percent, respectively. In case of crops, above ground, below ground and total biomass was significantly higher in sole intercrops than gamhar based agroforestry system. Total (Tree + interrops + Soil) carbon stock, carbon sequestration, carbon credit and carbon price were significantly affected by treatments, and was maximum in Sole Greengram-Mustard. Net carbon emission was also recorded lowest in Sole Greengram-Mustard for which the values were 811.55% and 725.24% and 760.69% lower than Sole Gamhar in 2016–17, 2017–18 and in pooled data, respectively.

‘Climate Healing Stones’: Common Minerals Offer Substantial Climate Change Mitigation Potential

This review proposes that mineral-based greenhouse gas (GHG) mitigation could be developed into a substantial climate change abatement tool. This proposal was evaluated via three objectives: (1) synthesise literature studies documenting the effectiveness of geological minerals at mitigating GHG emissions; (2) quantify, via meta-analysis, GHG magnitudes that could be abated by minerals factoring-in the carbon footprint of the approach; and (3) estimate the global availability of relevant minerals. Several minerals have been effectively harnessed across multiple sectors—including agriculture, waste management and coal mining—to mitigate carbon dioxide/CO2 (e.g., olivine), methane/CH4 (e.g., allophane, gypsum) and nitrous oxide/N2O (e.g., vermiculite) emissions. High surface area minerals offer substantial promise to protect soil carbon, albeit their potential impact here is difficult to quantify. Although mineral-based N2O reduction strategies can achieve gross emission reduction, their application generates a net carbon emission due to prohibitively large mineral quantities needed. By contrast, mineral-based technologies could abate ~9% and 11% of global CO2 and CH4 anthropogenic emissions, respectively. These estimates conservatively only consider options which offer additional benefits to climate change mitigation (e.g., nutrient supply to agricultural landscapes, and safety controls in landfill operations). This multi-benefit aspect is important due to the reluctance to invest in stand-alone GHG mitigation technologies. Minerals that exhibit high GHG mitigation potential are globally abundant. However, their application towards a dedicated global GHG mitigation initiative would entail significant escalation of their current production rates. A detailed cost-benefit analysis and environmental and social footprint assessment is needed to ascertain the strategy’s scale-up potential.

The Exponential-based Carbon Credit Cap in Carbon Cap-and-Trade Markets

The concept of carbon markets as developed in 1997 by the Kyoto Protocol was a good idea whose adoption and implementation by all counties and states would have significantly reduced the rate of emission of greenhouse gases into the atmosphere. The Carbon markets were proposed to be based on cap-and-trade whose forces of supply and demand would discourage the increase or steady emission of greenhouse gases and force companies to, gradually, revert to the use of clean energy in production. This would promote the net zero carbon emission target. The carbon markets were designed to have a cap whose nature is a specific number for all entities. The number represents the carbon quantity whose regulator would keep reducing until the net zero carbon is achieved. This nature of the cap encourages large emitters of greenhouse gases to shift to other jurisdictions that have soft regulations. It also encourages restructuring into smaller companies whose net emissions could be almost the same or more than before. In this paper, we have proposed an exponential-based cap that would leave little or no room for such market strategies. We have also demonstrated how the proposed cap can be implemented.

IN SMUGGLE WITH CLIMATE CHANGE, EXTRA–BUDGETARY FUND APPLICATION AS AN INSTRUMENT OF GREEN KEYNESIAN ECONOMIC POLICY

Green Keynesian Economics, which is a postmodern reflection of Keynesian economic thought, suggests that negativities, which are possible for environmental problems causing climate change to lead to, should be solved by active role public sector will undertake. As known, carbon emissions, emitted to atmosphere in global scale, may cause climate change via greenhouse effect. This case leads country economies to face to a set of problems. Green Keynesian Economics suggests a mix of simultaneous sustainable policies as a solution for a set of problems under consideration. The aim of this study is to suggest a financial instrument taking place in the scope of Green Keynesian School for Türkiye targeting to achieve net zero carbon emission as of the year 2053.

A carbon footprint assessment for pasture-based dairy farming systems in South Africa

Environmental impact evaluation of intensive dairy farming systems has been of growing interest recently as agriculture has several negative influences on the surrounding environment, including eutrophication, declines in biodiversity, and pollution of nearby waterbodies. Dairy production in particular is characterized by the emission of greenhouse gasses (GHG) contributing toward climate change. In this study, the carbon footprint of South African pasture-based dairy farming systems was assessed using a farm-gate life-cycle assessment (LCA) approach. A total of 82 pasture-based dairy farms across South Africa were assessed (2012–2022). The average carbon footprint across all dairy farming systems was 1.36 ± 0.21 kg CO2eq kg−1 fat- and protein-corrected milk produced (FPCM), which is higher than similar studies performed outside South Africa. Enteric fermentation had the largest influence on the carbon footprint, indicating the key role of methane as an emission source in ruminant dominated livestock systems. A difference in milk production efficiency was found between farming systems with the lowest and highest carbon footprints. Pasture-based dairy farming systems must be managed with adaptive management such as regenerative agriculture. Future research agendas should explore modeling approaches to assess the economic and environmental impact of dairy production, formulating a holistic understanding of the system dynamics while also quantifying net carbon emissions or sinks.

Health-Damaging Climate Events Highlight the Need for Interdisciplinary, Engaged Research.

In 2023 human populations experienced multiple record-breaking climate events, with widespread impacts on human health and well-being. These events include extreme heat domes, drought, severe storms, flooding, and wildfires. Due to inherent lags in the climate system, we can expect such extremes to continue for multiple decades after reaching net zero carbon emissions. Unfortunately, despite these significant current and future impacts, funding for research in climate and health has lagged behind that for other geoscience and biomedical research. While some initial efforts from funding agencies are evident, there is still a significant need to increase the resources available for multidisciplinary research in the face of this issue. As a group of experts at this important intersection, we call for a more concerted effort to encourage interdisciplinary and policy-relevant investigations into the detrimental health effects of continued climate change.

Performance investigation of a V-trough concentrating agrivoltaic system based on spectral splitting

Abstract In order to improve the comprehensive utilization efficiency of solar energy, a V-trough concentrating and splitting agrivoltaic hybrid system (VCSPVA system) is proposed in this paper, which transmits the red and blue spectral bands to crop field for photosynthesis conversion and concentrates the other bands to the solar panels for photoelectric conversion. Then, the power generation is completed with sustaining the crop growth, while the overall utilization efficiency of solar energy is improved significantly. The influence of key parameters is studied in detail. Results show that by adjusting trough angles, more reflected radiation can be received by the solar panels, minimizing the energy loss of the system. Through mathematical model establishment, the energy, economic and carbon emission evaluations of the proposed system are carried out. Consequently, the VCSPVA system has the highest annual efficiency of 16.96%, which is 39.15% and 45.93% higher than that of the traditional agrivoltaic system and photovoltaic-only system, respectively. Meanwhile, the net present value and carbon emission mitigation are $758680.99 and 0.25 t·m−2·a−1, respectively, which demonstrates a competitive option for dual land use and a significant role in reducing greenhouse gas emissions.

Examining the Social Costs of Carbon Emissions and the Ecosystem Service Value in Island Ecosystems: An Analysis of the Zhoushan Archipelago

Assessments of the ecosystem service value (ESV) and the social cost of carbon (SCC) inform national and government management decisions in the areas of human well-being and climate change mitigation and adaptation, respectively. Studying the correlation between the two provides a theoretical basis for low-carbon and high-quality regional development, achieving economic decarbonization, and improving human well-being. In this study, we take Zhoushan Archipelago as a case study, consider the ESV and SCC in Zhoushan Archipelago during the period 2010–2020, analyze their spatial development characteristics, and analyze the correlation between the two in time and space. The findings indicate that, with only a 1.5% change, the overall ESV in the Zhoushan Archipelago fell between 2010 and 2020. Conversely, there was a 1604.01 × 104 t increase in net carbon emissions and a quick 2452% increase in SCC. During the study period, a substantial positive association was found between ESV and SCC in the Zhoushan Archipelago, according to the global spatial correlation analysis of the two variables. It passed the test for p-value. This study presents a new potential way to solve the environmental and economic difficulties caused by climate change by providing a mechanism for quantitatively assessing the environment from the perspective of monetary worth. In order to improve the ecological security pattern and ease the burden of regional carbon emissions, it is vital to make use of regional advantages, maintain forests, and develop blue-carbon resources such as mudflats. It is a good idea to cooperate regionally with nearby metropolitan agglomerations. The study’s findings are crucial for advancing sustainable development planning in the Zhoushan Archipelago, both theoretically and practically.

Innovative measurement, trade-off-synergy relationship and influencing factors for agricultural net carbon emissions and effective supply of agricultural products in China

Sensitive zone of global climate change has been formed in China, and it has become a hot topic how can agriculture ensure food security and the supply of important agricultural products while achieving the “Dual Carbon” goal in the country. Based on such background, this paper uses the IPCC carbon emission calculation method, environmental input-output model and economic-water-carbon coefficient method to measure agricultural net carbon emissions, adopts bivariate spatial auto-correlation analysis and SYS-GMM to explore separately the relationship between agricultural net carbon emissions and effective supply of agricultural products, as well as the carbon reduction effect, growth effect and reasonable range of green technology innovation. The results show that: (1) China's agricultural net carbon emissions reveal a spatial distribution of “higher in the east than in the west than in the center” and a temporal characteristic of increasing year by year; China's effective supply of agricultural products shows an increasing trend and a spatial distribution of “higher in the east than in the center than in the west” in 2006–2012 and “higher in the east than in the west than in the center” in 2013–2020. (2) In 2006, 2010, 2015 and 2020, the number of provinces that belong to low-low agglomeration trade-off zone, low-high agglomeration synergy zone, non-significant zone, high-low agglomeration non-trade-off-synergy zone and high-high agglomeration trade-off zone averagely accounted for 12.500 %, 30.000 %, 26.667 %, 9.167 % and 21.667 % of the totality, respectively. (3) The carbon reduction and production growth effects of green technology innovation both show an inverted “U-shape”, and green technology innovation is conducive to both reducing agricultural net carbon emissions and improving supply of agricultural products when it is within a reasonable range of greater than 0.930. (4) Green technology innovation not only has significant spatial and temporal heterogeneity impact, but also exhibits a differential effect on productive agricultural carbon emissions, agricultural trade carbon emissions, agricultural carbon sinks, total output of agricultural products and agricultural net imports in international trade. Therefore, it is proposed that China should establish and improve green technology innovation incubation platforms, guide all participants to ensure the investment and application of green technology products within a reasonable range, formulate and implement regional differential policies and plan in accordance with local conditions, drive ultimately coordinated promotion of agricultural carbon emission reduction and product supply guarantee and lay an important foundation for achieving high-quality economic development and efficient ecological protection.

Research on the estimation and spatial pattern of net tourism carbon emissions in the Yellow River Basin from 2009 to 2019.

Based on panel data and remote sensing data of cities in the Yellow River Basin in China from 2009 to 2019, and using the tourism carbon footprint and tourism carbon carrying capacity models, the tourism carbon emissions, tourism carbon carrying capacity, and net tourism carbon of 65 cities in the Yellow River Basin were calculated. The balance and dynamic changes in carbon emissions and carbon fixation of urban tourism in the past ten years were compared. The results show that (1) tourism carbon emissions in the Yellow River Basin are generally on the rise, along with a distribution characteristic of downstream > middle reaches > upstream with obvious characteristics of urban agglomeration centrality within the basin; (2) the carbon carrying capacity of tourism is higher than that of tourism. The growth of carbon emissions is relatively slow, showing a spatial distribution pattern of high in the west and low in the east, which is mainly related to the geographical environment and economic development of the city; (3) the tourism carbon emissions and tourism carbon carrying capacity in the upstream areas can basically maintain a balance, but in the middle and lower reaches of the region, they show a carbon surplus. There is a significant positive spatial correlation in urban net tourism carbon emissions, and the clusters are mainly H-H and L-L.