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Unsustainable overexploitation of groundwater for agricultural irrigation has led to rapid groundwater depletion and severe environmental damage in the semi-arid Hebei Plain of China. Field experiments have recommended annual winter fallowing (i.e., forgoing winter wheat production) as the most effective way to replenish groundwater. However, adopting the recommendation across the Hebei Plain would lead to a significant reduction in total wheat production. This research aims to find the most favorable water-sustainable cropping systems for different localities in the Hebei Plain, which at the regional aggregation level maintains the uppermost overall levels of wheat and grain production respectively. Our simulations indicate that in the Hebei Plain, an optimal allocation of a wheat-early maize relay intercropping system and an early maize-winter fallow cropping system across the Hebei Plain could lead to significant water savings while minimizing grain production losses to around 11%. Compared to the prevailing wheat and summer maize cropping system , to prevent a drop in the water table, 39% of the current wheat cropping land would need to be fallowed in winter, reducing irrigation water use by 2639 × 106 m3. Replacing the prevailing wheat and summer maize cropping system with our optimized allocation system could lead to a 36% increase in total maize production and 39% decrease in total wheat production, resulting in total agricultural irrigation water savings of 2322 × 106 m3 and a total grain production reduction by 11%. The findings indicate the potential benefits of our cropping system adaptation method to meet the challenge of recovering local groundwater level with the least possible reduction of wheat and total grain production in the Hebei Plain. • The current practice of overexploiting groundwater in the Hebei Plan is unsustainable • We search for the desired water-sustainable cropping systems across localities in the Plain • Minimizing the reduction of wheat production and recovering water table • The crop allocation procedure and findings enrich the literature and inform policy makers [ABSTRACT FROM AUTHOR]

The global food trade network (FTN) plays a critical role in ensuring food security. Given the increasing scale and complexity of trade, understanding the inherent dynamics and potential vulnerabilities of FTN becomes an urgent concern. Here, this study employed complex network method to investigate the structure, dynamics, and vulnerabilities of the trade networks associated with four main food crops (rice, maize, wheat, and soybeans) over the period 2000 to 2019. Our results show that the FTN has features consistent with both scale-free and small-world networks. A small percentage of 10% of major food producing countries trade with a significant proportion of 80% of all countries within the network. In the examined period, FTN has experienced remarkable changes, emerging economies such as China, India, Brazil and Russia have become more important, offsetting the historical dominance of nations such as the United States, Canada and Australia. In addition, many countries become increasingly reliant on food imports, the number of their trading partners within the FTN is decreasing, highlights potential increasing vulnerabilities. Simulation analysis also show that disruptions affecting about 5% of nations could seriously destabilize the FTN, which would be a cautionary tale for the stability of future food systems. This research provides policymakers with a fundamental perspective on mitigating potential risks in global FTN. [ABSTRACT FROM AUTHOR]

Insufficient precipitation and continuous over-exploitation of groundwater for agricultural irrigation led to rapid drop of groundwater table in a large part of the North China Plain (NCP), the bread basket of China. It has become widely acknowledged that current practice of winter wheat-summer maize sequential cropping system (WM-S) in the NCP will have to come to an end as soon as possible. Great research efforts have been made at the local level via both field experiments and model simulations to construct groundwater neutral cropping systems but virtually all such constructs show a substantial penalty on total output per unit of land per year. In this research, we propose a strategy to meet the double challenge of maintaining regional grain production level and recovering local groundwater table: 1) Widely adopt winter fallow and early-sowing summer maize monocropping (E-M) in water scarce part of the region to enable groundwater recovery; 2) replace WM-S by wheat-maize relay intercropping system (WM-R) in the water richer part of the NCP to increase grain production so as to compensate yield losses in the water scarce part of the region. Our simulations using DSSAT 4.6 at the site level show that both yield and water productivity of E-M are 33.7% and 41.8% higher than those of existing summer maize, with less than 20% of increase in water requirement. In comparison with spring maize, E-M requires 62.4% less irrigation water, with a yield penalty of only 4.52%. At the regional scale, the simulations targeting at maximizing groundwater saving in water scarce area subject to maintaining the current level of regional total output indicate that about 20.45% of the wheat planting area can be put on fallow in winter, most of which is located in the driest regions of the NCP. This can result in a large amount of groundwater saving at 5.62 × 10 9 m 3 and a substitution of wheat by maize at 24.3% of the total wheat output. These findings provide new rooms for the relevant policy makers and stakeholders to address the urgent groundwater recovering issues in the northern NCP without compromising the level of food grain production of the region. [ABSTRACT FROM AUTHOR]

The thermal power sector is responsible for more than 40% of China's carbon mitigation targets, making it critical in achieving carbon neutrality. However, the adoption of the "one-size-fits-all" discontinuation and "campaign-style" mitigation, driven by mandatory national regulatory constraints, has triggered pressing livelihoods and economic shocks such as electricity restrictions and shortages. To balance the carbon mitigation targets with electricity security in China, this study utilizes Morishima elasticity of substitution to identify heterogeneous production strategies for each plant under carbon neutrality. More specifically, how thermal power plants respond to carbon reduction targets. Results indicate that almost half of the thermal power plants could reconcile national targets with corporate profits, while the remaining plants could only meet national binding targets by reducing production. Additionally, about 20% of inefficient plants will opt to transfer emissions, such as increasing weakly regulated emissions, to secure revenue. The basic characteristics of thermal power plants under different production strategies are also analyzed. Finally, this study discusses how to develop electricity-carbon synergies and prevent productive speculation under the carbon neutrality transition from the perspectives of corporate production and tax deferment policy, and propose corresponding policy suggestions. [Display omitted] • Carbon neutrality target in China has unintentionally caused severe power shortage. • Heterogeneous production strategies are identified using elasticity analysis. • Nearly half of thermal plants can reconcile national targets with corporate profits. [ABSTRACT FROM AUTHOR]

Reducing inequality, eradicating poverty and achieving a carbon-neutral society are recognized as important components of the United Nations' Sustainable Development Goals. In this study, we focus on carbon and energy inequality between and within ten Latin American and Caribbean (LAC) countries. Detailed carbon and energy footprint were estimated by combining the consumption profiles (2014) in ten LAC countries with environmental extended multi-regional input-output (MRIO) analysis. Our results show significant inequality of regional total and per capita carbon and energy footprint across the studied LAC countries in 2014. The top 10% income category was responsible for 29.1% and 26.3% of the regional total carbon and energy footprint, and their per capita carbon and energy footprint were 12.2 and 7.5 times of the bottom 10% earners in that region. The average carbon footprint of studied LAC countries varied between 0.53 and 2.21 t CO 2 e/cap (ton of CO 2 equivalent, per capita), and the energy footprint ranged from 0.38 to 1.76 t SOE/cap (ton of Standard Oil Equivalent, per capita). The huge difference in total and per capita carbon emissions and energy consumption of different income groups suggests notable differences in climate change responsibility, and supports policies for achieving sustainable consumption in terms of carbon tax, renewable energy subsidy, and decarbonizing the consumption structure in different LAC countries. [ABSTRACT FROM AUTHOR]

Benggang is one of the most serious soil erosion problems in tropical and subtropical areas in southern China. Little work has been reported on the surface properties of soil colloidal particle and its influence on soil swelling of different soil layers in collapsing wall of Benggang. In this present work, the effects of sodium concentration on soil swelling, and the correlations between soil swelling rates and soil colloidal surface properties were comprehensively evaluated by carefully examining soil physicochemical properties and soil colloidal surface properties of red, sandy and detritus soil layers from a collapsing wall. Our results showed that the soil swelling rates of red, sandy and detritus soil layers all exponentially decreased with increasing initial water contents. The relationship between soil swelling rate and the thickness of shear plane showed an extremely significant negative correlation for red soil layer and no correlation for sandy and detritus soil layers. Moreover, the elevating sodium concentrations reduced the thickness of shear plane from 39.69 to 0.76 nm for red soil layer, followed from 22.56 to 0.79 nm for sandy soil layer and from 18.61 to 0.64 nm for detritus soil layer. These findings indicated that the soil particle interactions played a crucial role in the development and occurrence of Benggang. This work will be helpful in understanding the mechanisms of soil mass loss on the gully head and collapsing wall of Benggang. [ABSTRACT FROM AUTHOR]

• Multi-level household emission patterns are recognized by machine learning models. • Demographic structure, age and appliances are key factors to vary emission levels. • Customized emission reduction paths are proposed to guide energy-saving behaviours. • Household appliance usage obtains the largest reduction potential to mitigate emissions. Given by the ambitious GHG mitigation targets set by governments worldwide, household is playing an increasingly important role for reaching listed reduction goals. Consequently, a deep understanding of its emission patterns and the corresponding driving factors are of great importance for exploring the untapped potential of household. However, how to accurately capture household emission features still demand further support from both data and method development. To bridge this knowledge gap, we try to use machine learning technology, which is well linked to the micro-level household survey data, to identify key determinants that could explain the household home-energy consumption and associated emissions. Here, we investigate the household CO 2 emissions based on a representative survey which covers 31,133 households in Japan. Six types of machine learning process are employed to find key factors determining to different household emission patterns. Results show that demographic structure, average age and electricity-intensive appliances (electric water heaters, electric heaters, etc.) are most significant driving factors that explain differences in household emissions. Results also further verified that differences in driving factors can be observed in identifying various household emission patterns. The results of study provide vital information for the customized decarbonization pathways for households, as well as discussing further energy-saving behaviours from data-oriented method. [ABSTRACT FROM AUTHOR]

In remote areas, people experiencing persistent poverty still face challenges related to energy shortages and air pollution. Due to the escalating global climate change crisis, herding communities in the Qinghai–Tibetan Plateau remain vulnerable to significant threats related to energy security and accessibility. These communities are vulnerable because they occupy underdeveloped regions and depend heavily on traditional energy sources. To explore this issue, we conducted a comprehensive questionnaire-based survey involving 473 herders across 13 counties on the Qinghai–Tibetan Plateau. The findings revealed that per capita energy consumption in herder households averaged 2021.793 kgce/year. Noncommercial energy sources constituted a substantial 61.66%, with the predominant one being cow dung, and refrigerators are the highest energy consumption household appliances. By applying geographically weighted regression (GWR), we examined seven key natural and socio-economic factors influencing solid energy use. These factors included annual per capita household income, the highest level of education, indoor and outdoor oxygen concentrations, the labor force population, housing size, and altitude. Notably, the first three variables exhibited negative correlations, while the rest demonstrated positive correlations. The impact of oxygen concentrations on household energy consumption was particularly significant, as demonstrated by the notable correlation. In this study, we elucidated the intricate structure and determinants of energy consumption structure within herders. [ABSTRACT FROM AUTHOR]

Highlights • Northeast China is the center of maize production in the country. • Assess varying impacts of drought across different maize growth stages in Northeast China. • Probability of extreme events in irrigation water shortage will increase in the future. • Irrigation infrastructure and efficient irrigation scheme and technologies are of great importance. Abstract Northeast Farming Region of China (NFR) produces about one-third of the national maize output. Shortage of crop irrigation water is one of the main threat to the stable level of maize production in the NFR. Previous studies on the sensitivity of maize production to drought are typically based on field experiments and treat the maize growing season as a whole, with rare attention to the varying impacts of drought across different maize growth stages. Given the importance of NFR on China's food security, it is crucial to optimize the irrigation schedule to mitigate the adverse effects of drought. In this study, we employ Agro-ecological Zone (AEZ) model to investigate how climate change affects irrigation water requirement (IWR) of maize during different growth stages and under different climate change scenarios. Results indicate that the NFR would experience a substantial increase in the probability of extremely shortage of crop irrigation water under future climate change. The ensemble simulation under future climate projections indicates more frequent demands for irrigation with substantially increased amount in the mid-season stage (G3) when maize is more sensitive to water deficit compared with other stages. These findings indicate that earlier planning of irrigation infrastructure and development of more efficient irrigation scheme and technologies is of great importance to secure maize production in the region. [ABSTRACT FROM AUTHOR]

There is unequal spatial distribution of resource endowment, population density, industrial structure, and economic development with diverse differences in labor, energy, and capital productivities in China. However, previous studies paid little attention to the determinants of CO 2 transfers embodied in electricity trade. In this study, we use both the absolute and comparative advantage theories to reveal the determinants of embodied CO 2 transfers through electricity trade within China. Results show that China's electricity sector has higher labor productivity but lower asset efficiency and energy productivity than that of mining and manufacturing sectors. The large-scale electricity trade alleviates the shortage of electricity supply in developed regions by outsourcing to the less-developed regions, reduces the unequal spatial distribution of coal and natural gas reserves, and changes CO 2 flow embodied in power grid. Econometric analysis shows that coal reserve contributes to the increase of embodied CO 2 emission, while natural gas reduces the embodied CO 2 emission. The regional differences in the opportunity cost of labor productivity of non-electricity sector are the dominant factor of the embodied CO 2 transfers through electricity trade within China, while asset efficiency and energy productivity are not significant in the regressions. Our findings could provide details about China's power grid expansion when confronting climate mitigation in the future. • Absolute and comparative advantage theories in determining the embodied CO 2 transfers through electricity trade. • Electricity sector has higher labor productivity but lower asset efficiency and energy productivity than other sectors. • The electricity trade alleviates the shortage of electricity supply in developed regions by outsourcing. • Coal reserve increases the embodied CO 2 emission, while natural gas reduces the embodied CO 2 emission. • The opportunity cost of labor productivity of non-electricity sector is the dominant factor in the embodied CO 2 transfers. [ABSTRACT FROM AUTHOR]

In recent decades, many megacities in the world have suffered from increasingly frequent heat waves. During heat waves, air-conditioners, refrigerators, and electric fans add a considerable peak demand on electrical utility grids, and on the supply side, high temperatures exert adverse effects on electricity generation, transmission, and distribution. Without pro-active planning and mitigation measures, the overloading would result in more frequent blackouts (the complete failure of electricity distribution) and brownouts (voltage reductions). To facilitate a pro-active planning, which aims to replace blackouts and brownouts by a rationing regime in selected sectors, this research proposes an integrated modeling tool which couples a regression model between daily electricity use and maximum temperature over the summer and a mixed input–output model with supply constraints. With the help of available data in Shanghai, China, we show that this tool is capable of quantitatively estimating the overall economic effects and sequential changes in carbon emissions, which a given magnitude of power rationing in a specific sector can exert across all sectors. The availability of such information would enable decision makers to plan an electricity rationing regime at the sector level to meet the double criterions of minimizing the overall economic losses and maximizing the extent of carbon emission reduction. [ABSTRACT FROM AUTHOR]

There have been increasing concerns on risks and uncertainty posed by climate change to China's future crop production. The existing assessments using popular process-based and site-specific crop growing models highlight the significant extent of climate-induced yield reduction, and thus suggest a scary downward risk for China's future food production. Surprisingly, much less attention has been paid to exploring the potential gains that may also be brought by climate change. To address this imbalance, we develop an integrated agro-climatic and ecological assessment tool that is capable of detecting the shifts of multicropping opportunities under different climate change scenarios. The application of this tool to the context of China reveals significant extension of multicropping opportunities brought in by climate change. We argue for an active adaptation to such emerging opportunities through both market and policy incentives, because the aggregate gain of such adaptation is sufficient to outweigh the loss as revealed by the existing assessments. [ABSTRACT FROM PUBLISHER]