Promoting potato as staple food can reduce the carbon–land–water impacts of crops in China

Transitioning to healthy and sustainable diets has higher environmental and affordability trade-offs for emerging and developing economies

Switching to alternative global diets offers established benefits, but the challenges and opportunities for individual countries during and after the transition remain unassessed. In this study, we project changes in water use, dietary quality, and food affordability under four dietary scenarios (including Mediterranean diet, the EAT-Lancet diet, the Healthy US-Style diet, and Vegetarian diet), assessing the potential implications at the country level from 2020 to 2070. Here, we show that by 2070, transitioning to healthy and sustainable diets can improve dietary quality by 30.29 - 45.43%, with all countries reducing water use (1.21 - 14.73%) and increasing food affordability (9.29 - 63.23%). However, in the initial phases, increased food demand escalated water use and worsened food affordability, especially in emerging and developing economies, with the maximum average deterioration being 2.62% and 13.06%, respectively. These highlight the need for long-term planning and financial support to ensure successful global transitions.

Localized nutrient management practices enhance the environmental-economic sustainability in potato production of China

Potatoes, as the fourth most important staple crop in China, play a crucial role in ensuring national food security. However, potato production is heavily reliant on inputs such as fertilizers and pesticides, leading to significant environmental challenges that compromise the sustainability of this production. A systematic evaluation of the current state of potato production sustainability in China and its potential for improvement is an urgent scientific issue that needs to be addressed. This study employs emergy sustainability index (ESI), energy return on investment (EROI), energy efficiency cost (EEC), and energy exchange ratio (EnER) methods to assess the environmental and economic aspects of potato production at the county level in China. Results indicate that, in 2015, the average ESI, EROI, EEC, and EnER for potato production in China were 1.37 (0.1-5.4), 2.21 (0.18-7.44), 0.06 (0.01-0.48) $/MJ, and 13.52 (2.68-112.40) MJ/$, respectively, with considerable spatial heterogeneity at the county level. Regions with higher sustainability in potato production are primarily concentrated in the northwest, which is also China's main potato-growing area. The random forest analysis identified yield, phosphorus, and nitrogen fertilizers as key factors influencing the sustainability of potato production. Regionally differentiated fertilizer management strategies led to a 43% and 35% increase in ESI and EROI, respectively, while EEC and EnER decreased by 50% and 47%. This study systematically explores the relationship between the environmental and economic dimensions of potato production from an energy perspective and proposes optimized management strategies for synergistic environmental-economic development. It provides methodological support and scientific guidance for promoting sustainable potato production and offers insights for global potato sustainability systems.

What is a sustainable diet in the Norwegian context?

INTRODUCTION

Sustainable diets promote health and wellbeing and have low environmental impact. They should be accessible, affordable, safe, equitable and culturally acceptable. Translating these general principles into Norwegian-specific dietary recommendations is essential, as foods beneficial for health tend to also be environmentally sustainable. Following the dietary recommendations is an important step towards sustainability.

AIM

To identify challenges and potential solutions for transitioning towards more sustainable diets in Norway.

METHODS

We used scientific articles, reports, policy documents, and statistics on Norwegian food production and consumption to discuss a sustainable diet in a Norwegian context.

RESULTS AND DISCUSSION

There is a large gap between dietary guidelines and actual consumption. More than 60% of the calories in the Norwegian diet are based on imported foods and feed. Changing people's diet is identified as central in transforming the food system to become more sustainable, as is prioritizing the use of local resources. Good animal health and welfare are also fundamental premises for a sustainable food system.

CONCLUSIONS

Transitioning to a more sustainable diet requires comprehensive efforts at multiple levels. There is considerable room for action to increase the use of Norwegian resources in a sustainable and responsible way. Potential strategies include reducing meat intake in favour of plant-based foods and fish, consuming more local products, decreasing food waste and supporting agricultural practices that promote environmental and social sustainability. A more sustainable diet may also lead to significantly increased self-sufficiency and food security in Norway.

Growing contribution to radiative forcing from China's on-farm nitrous oxide emissions requires more attention

Agricultural systems are important emission sources of non-CO2 greenhouse gases (GHGs), including the relatively short-lived GHG methane (CH4). As a pivotal emitter, China's CH4 emissions have received wide attention. For the first time, this study applied an indicator of radiative forcing-based climate footprint (RFCF) to compare the climate impacts of China's on-farm non-CO2 GHG emissions including CH4 and nitrous oxide (N2O). We found that, with short atmospheric lifetime, CH4's contribution to RFCF has plateaued in 2011 at 3.37 mW m-2 and achieved the goal of net zero increase to radiative forcing (RF) in 2017. However, the long-lived N2O emissions form an increasingly important proportion of the total RFCF at China's farm gate over time. The contribution from CH4 emissions to the total global on-farm RFCF experienced a downward trend, while that from N2O emissions has been trending upward during 1961-2021. It indicates the need of more attention on the long-lived climate forcer N2O in China. The RFCF indicator informs about whether progress is being made toward RF stabilization. It is recommended to widely apply the RFCF approach to re-examine and inform climate actions in China's agricultural systems as well as sectors with substantial biogenic CH4 emissions.

Coupling relationship and development patterns of agricultural emission reduction, carbon sequestration, and food security

In-depth exploration of the coupling relationship between agricultural emission reduction and carbon sequestration (ERCS) and food security provides an important basis for promoting sustainable low-carbon development in agriculture. This research investigates the coupling mechanisms and the current state of coordinated development of agricultural ERCS and food security using provincial panel data from 2001 to 2022 in China. The agricultural ERCS level shows an upward trend, with higher levels in the north and lower in the south; externalities are positive in the north but negative in the south. Significant dynamic interactions and spatial correlations between the agricultural ERCS and food security exist, with a local spatial agglomeration pattern of "north-south opposition". Areas of high-high agglomeration are mainly concentrated in the north, while low-low agglomeration areas are primarily in the south. High-high agglomeration areas drive growth in transitional and low-growth areas through diffusion effects. The average coupling coordination degree of provinces increased from 0.432 to 0.473, indicating more coordinated development, and with a decreasing polarization trend. The spatial distributions of the coupling coordination degree and the relative development index are higher in the north and lower in the south, with many areas showing high adjustment, low adjustment, and high antagonism, particularly in the south where the number of high antagonistic areas has decreased. Implementing differentiated development strategies between the north and the south, using spatial agglomeration characteristics to optimize regional policies, focusing on the diffusion effects of high-coupling coordination areas to drive the development of low-growth and transitional areas, and enhancing the lagged terms can promote sustainable coordinated agricultural development.

Targeted opportunities to mitigate water scarcity, inequality, and inequity embedded in international food trade for vulnerable countries

International food trade reshapes regional water scarcity through virtual water transfers (VWT), influencing water use equality and equity. This study examines eight populous yet impoverished countries in Africa and Asia, representing 30 % of the global poor population and contributing 20 % to agricultural VWT. Despite their significant role, these countries have been understudied due to a lack of data or attention. By integrating multiple datasets and models, we assess how international food trade impacts water scarcity, inequality, and inequity within these countries and identify the driving factors. Our findings reveal varied outcomes: Uganda and Ethiopia benefit from reduced water scarcity (∼40 % and ∼7 %) and improved equality and equity (∼90 % and ∼68 %), while India and Pakistan face exacerbated scarcity (∼4 % and ∼2 %) and widening inequality and inequity (∼4 % and ∼7 %). The effects are largely driven by critical trade flows of staple and cash crops like rice, sugar cane, and cotton among developing countries, propelled by comparative advantages in agricultural production, econo-geography, food demand, and water endowment between importers and exporters. Addressing these water challenges involves diversifying import channels to reduce reliance on detrimental trade flows, such as India's rice exports to Iran, while promoting beneficial flows, like Bangladesh's cotton imports from India, through trade agreements. Additionally, implementing pro-poor water policies (e.g., providing water subsidies) and water-saving techniques (e.g., adopting drip irrigation) is crucial, though caution is needed to avoid unintendedly marginalizing vulnerable groups through large-scale water projects.

Sustainable food systems under environmental footprints: The delicate balance from farm to table

In today's world, agriculture is not only about food production but also a critical factor in global environmental change, economic stability, and human health, among other aspects. With population growth and increasingly scarce resources, exploring sustainable development of food systems has become crucial. Achieving this goal requires striking a delicate balance among food security, economic development, ecological environment, and human health. Traditional approaches to sustainable agricultural development research often focus solely on singular domains, overlooking the inherent connections and interactions among environmental, socioeconomic, and health dimensions. This perspective limits our comprehensive understanding of food systems. Environmental footprint assessments can be integrated with economic, systemic, and decision models to analyze environmental, socioeconomic, and health issues within food systems. This integration accurately captures the diversity, overlap, accumulation, and heterogeneity of environmental pressures resulting from human and natural factors. Therefore, we propose an innovative conceptual framework that considers environmental, socioeconomic, and health dimensions as crucial components, with the environmental footprint indicators at its core, to link various stages from farm to table. This framework constructs an evidence gap map, integrating dispersed data and perspectives from existing literature, thus showing knowledge gaps across these domains. Such an interdisciplinary approach not only provides a more comprehensive perspective on the multidimensional complexity of sustainable food systems but also reveals potential synergies and conflicts among environmental, socioeconomic, and health domains, thereby guiding more comprehensive and cautious policy-making. Importantly, it provides direction for future research to achieve the sustainable development of food systems, emphasizing the necessity of a comprehensive, integrated research perspective, particularly in strengthening studies on composited footprints, viewing the entire farm-to-table continuum holistically. Stakeholders must collaborate and coordinate environmental, socioeconomic, and health objectives to drive the sustainable development of food systems.

Climate-adaptive crop distribution can feed food demand, improve water scarcity, and reduce greenhouse gas emissions

Optimizing crop distribution stands as a pivotal approach to climate change adaption, enhancing crop production sustainability, and has been recognized for its immense potential in ensuring food security while minimizing environmental impacts. Here, we developed a climate-adaptive framework to optimize the distribution of staple crops (i.e., wheat, maize, and rice) to meet the multi-dimensional needs of crop production in China. The framework considers the feasibility of the multiple cropping systems (harvesting more than once on a cropland a year) and adopts a multi-dimensional approach, incorporating goals related to crop production, water consumption, and greenhouse gas (GHG) emissions. By optimizing, the total irrigated area of three crops would decrease by 7.7 % accompanied by a substantial 69.8 % increase in rain-fed areas compared to the baseline in 2010. This optimized strategy resulted in a notable 10.0 % reduction in total GHG emissions and a 13.1 % decrease in irrigation water consumption while maintaining consistent crop production levels. In 2030, maintaining the existing crop distribution and relying solely on yield growth would lead to a significant maize production shortfall of 27.0 %, highlighting a looming challenge. To address this concern, strategic adjustments were made by reducing irrigated areas for wheat, rice, and maize by 2.3 %, 12.8 %, and 6.1 %, respectively, while simultaneously augmenting rain-fed areas for wheat and maize by 120.2 % and 55.9 %, respectively. These modifications ensure that production demands for all three crops are met, while yielding a 6.9 % reduction in GHG emissions and a 15.1 % reduction in irrigation water consumption. This optimization strategy offers a promising solution to alleviate severe water scarcity issues and secure a sustainable agricultural future, effectively adapting to evolving crop production demands in China.

Toward More Realistic Estimates of Product Displacement in Life Cycle Assessment

Life-cycle assessment (LCA) is one of the most widely applied methods for sustainability assessment. A main application of LCA is to compare alternative products to identify and promote those that are more environmentally friendly. Such comparative LCA studies often rest on, explicitly or implicitly, an idealized assumption, namely, 1:1 displacement between functionally equivalent products. However, product displacement in the real world is much more complicated, affected by various factors such as the rebound effect and policy schemes. Here, we quantitatively review studies that have considered these aspects to evaluate the magnitude and distribution of realistic displacement estimates across several major product categories (biofuels, electricity, electric vehicles, and recycled products). Results show that displacement ratios concentrate around 40-60%, suggesting considerable overestimation of the benefits of alternative products if the 1:1 displacement assumption was used. Overall, there have been a small number of modeling studies on realistic product displacement and their scopes were limited. Additional research is needed to cover more product categories and geographies and improve the modeling of market and policy complexities. As such research accumulates, their displacement estimates can form a database that can be drawn upon by comparative LCA studies to more accurately determine the environmental impacts of alternative products.

Climate change exacerbates the environmental impacts of agriculture

Agriculture's global environmental impacts are widely expected to continue expanding, driven by population and economic growth and dietary changes. This Review highlights climate change as an additional amplifier of agriculture's environmental impacts, by reducing agricultural productivity, reducing the efficacy of agrochemicals, increasing soil erosion, accelerating the growth and expanding the range of crop diseases and pests, and increasing land clearing. We identify multiple pathways through which climate change intensifies agricultural greenhouse gas emissions, creating a potentially powerful climate change-reinforcing feedback loop. The challenges raised by climate change underscore the urgent need to transition to sustainable, climate-resilient agricultural systems. This requires investments that both accelerate adoption of proven solutions that provide multiple benefits, and that discover and scale new beneficial processes and food products.

Haplotype-resolved genome and mapping of freezing tolerance in the wild potato Solanum commersonii

Solanum commersonii (2n = 2x = 24, 1EBN, Endosperm Balance Number), native to the southern regions of Brazil, Uruguay, and northeastern Argentina, is the first wild potato germplasm collected by botanists and exhibits a remarkable array of traits related to disease resistance and stress tolerance. In this study, we present a high-quality haplotype-resolved genome of S. commersonii. The two identified haplotypes demonstrate chromosome sizes of 706.48 and 711.55 Mb, respectively, with corresponding chromosome anchoring rates of 94.2 and 96.9%. Additionally, the contig N50 lengths are documented at 50.87 and 45.16 Mb. The gene annotation outcomes indicate that the haplotypes encompasses a gene count of 39 799 and 40 078, respectively. The genome contiguity, completeness, and accuracy assessments collectively indicate that the current assembly has produced a high-quality genome of S. commersonii. Evolutionary analysis revealed significant positive selection acting on certain disease resistance genes, stress response genes, and environmentally adaptive genes during the evolutionary process of S. commersonii. These genes may be related to the formation of diverse and superior germplasm resources in the wild potato species S. commersonii. Furthermore, we utilized a hybrid population of S. commersonii and S. verrucosum to conduct the mapping of potato freezing tolerance genes. By combining BSA-seq analysis with traditional QTL mapping, we successfully mapped the potato freezing tolerance genes to a specific region on Chr07, spanning 1.25 Mb, with a phenotypic contribution rate of 18.81%. In short, current research provides a haplotype-resolved reference genome of the diploid wild potato species S. commersonii and establishes a foundation for further cloning and unraveling the mechanisms underlying cold tolerance in potatoes.

Climate adaptation through crop migration requires a nexus perspective for environmental sustainability in the North China Plain

Crop migration can moderate the impacts of global warming on crop production, but its feedback on the climate and environment remains unknown. Here we develop an integrated framework to capture the climate impacts and the feedback of adaptation behaviours with the land-water-energy-carbon nexus perspective and identify opportunities to achieve the synergies between climate adaptation and environmental sustainability. We apply the framework to assess wheat and maize migration in the North China Plain and show that adaptation through wheat migration could increase crop production by ~18.5% in the 2050s, but at the cost of disproportional increment in land use (~19.2%), water use (~20.2%), energy use (~19.5%) and carbon emissions (~19.9%). Irrigation and fertilization management are critical mitigation opportunities in the framework, through which wheat migration can be optimized to reduce the climatic and environmental impacts and avoid potential carbon leakage. Our work highlights the sustainable climate adaptation to mitigate negative environmental externalities.

Differential gene expression in irradiated potato tubers contributed to sprout inhibition and quality retention during a commercial scale storage

Current study is the first ever storage cum market trial of radiation processed (28 tons) of potato conducted in India at a commercial scale. The objective was to affirm the efficacy of very low dose of gamma radiation processing of potato for extended storage with retained quality and to understand the plausible mechanism at the gene modulation level for suppression of potato sprouting. Genes pertaining to abscisic acid (ABA) biosynthesis were upregulated whereas its catabolism was downregulated in irradiated potatoes. Additionally, genes related to auxin buildup were downregulated in irradiated potatoes. The change in the endogenous phytohormone contents in irradiated potato with respect to the control were found to be correlated well with the differential expression level of certain related genes. Irradiated potatoes showed retention of processing attributes including cooking and chip-making qualities, which could be attributed to the elevated expression of invertase inhibitor in these tubers. Further, quality retention in radiation treated potatoes may also be related to inhibition in the physiological changes due to sprout inhibition. Ecological and economical analysis of national and global data showed that successful adoption of radiation processing may gradually replace sprout suppressants like isopropyl N-(3-chlorophenyl) carbamate (CIPC), known to leave residue in the commodity, stabilize the wholesale annual market price, and provide a boost to the industries involved in product manufacturing.

Identifying synergistic solutions for the food-energy-water nexus via plastic film mulching cultivation

Food security, water scarcity, and excessive fossil energy use pose considerable challenges to sustainable agriculture. To understand how rain-fed farming systems on the Loess Plateau, China, reconcile yield increases with ecological conservation, we conducted an integrated evaluation based on the denitrification-decomposition (DNDC) model, agricultural statistics data using the Food-Energy-Water (FEW) nexus indicator. The results showed that maize yields with ridge-furrow plastic film mulching (PFM) were 3479, 8942, and 11,124 kg ha-1 under low (50 kg N ha-1), medium (200 kg N ha-1), and high (350 kg N ha-1) nitrogen (N) fertilizer rates, respectively, and that PFM increased yield and water use efficiency (WUE) by 110-253 % and 166-205 % compared to using no mulching (control, CK), respectively. Plastic film mulching also increased net energy (126-436 %), energy use efficiency (81-578 %), energy productivity (100-670 %), and energy profitability (126-994 %), and nitrogen fertilizer, compound fertilizer, and diesel fuel consumption by agricultural machinery were the main energy inputs. The PFM system reduced water consumption during the maize growing season and the green water footprint and gray water footprint decreased by 66-74 % and 44-68 %, respectively. The FEW nexus indicator, based on a high production at low environmental cost scenario, was greater under the PFM system and had the widest spatial distribution area at the medium-N application rate. Among the environmental factors, the nexus indicator was negatively correlated with precipitation (-0.37), air temperature (-0.36), and the aridity index (-0.36), but positively correlated with elevation (0.17). Our results suggest that the PFM system promotes resource-saving while increasing yields and moves dryland agriculture in an environmentally friendly direction, thus promoting the sustainable development of agroecosystems.

Soil Geobacteraceae are the key predictors of neurotoxic methylmercury bioaccumulation in rice

Contamination of rice by the potent neurotoxin methylmercury (MeHg) originates from microbe-mediated Hg methylation in soils. However, the high diversity of Hg methylating microorganisms in soils hinders the prediction of MeHg formation and challenges the mitigation of MeHg bioaccumulation via regulating soil microbiomes. Here we explored the roles of various cropland microbial communities in MeHg formation in the potentials leading to MeHg accumulation in rice and reveal that Geobacteraceae are the key predictors of MeHg bioaccumulation in paddy soil systems. We characterized Hg methylating microorganisms from 67 cropland ecosystems across 3,600 latitudinal kilometres. The simulations of a rice-paddy biogeochemical model show that MeHg accumulation in rice is 1.3-1.7-fold more sensitive to changes in the relative abundance of Geobacteraceae compared to Hg input, which is recognized as the primary parameter in controlling MeHg exposure. These findings open up a window to predict MeHg formation and accumulation in human food webs, enabling more efficient mitigation of risks to human health through regulations of key soil microbiomes.

Estimating the carbon footprint of Mexican food consumption based on a high-resolution environmentally extended input-output model

Increased global attention is being paid to the food-health-climate trilemma. In this study, we evaluate the climate impacts of Mexico's food consumption patterns by creating a high-resolution (262 sectors) Environmentally Extended Input-Output (EEIO) model called MXEEIO. We focus on the differences between food away from home (FAFH) and food at home (FAH) and compare Mexico's results with those of the USA. The results show that the main components of food spending in Mexico were meat, baked products, and beverages, raising concerns about their potential negative health effects if consumed excessively. Mexico's total greenhouse gas (GHG) emissions from food consumption were estimated at 149 million metric tons (MMT) in 2013, as opposed to 797 MMT for the USA. Meat and dairy products were the main contributors to Mexico's food-related GHG emissions, accounting for 57% of total emissions. Mexico spent a much smaller proportion of food-related income on FAFH than the USA (13% vs. 52%), suggesting great potential for growth as Mexico's per capita GDP continues to rise. Detailed contribution analysis shows that reducing Mexico's food-related GHG emissions would benefit most from a transition to low-carbon cattle farming, but mitigation efforts in other sectors such as crop cultivation and electricity generation are also important. Overall, our study underscores the significance of food-related GHG emissions in Mexico, especially those from meat and dairy products, and the mitigation challenges these sectors face.

Isolation, Purification and Tyrosinase Inhibitory Activity of Anthocyanins and Their Novel Degradation Compounds from Solanum tuberosum L

To explore the composition of anthocyanins and expand their biological activities, anthocyanins were systematically isolated and purified from tubers of Solanum tuberosum L., and their tyrosinase inhibitory activity was investigated. In this study, two new anthocyanin degradation compounds, norpetanin (9) and 4-O-(p-coumaryl) rhamnose (10), along with 17 known anthocyanins and their derivatives, were isolated and purified from an acid-ethanolic extract of fresh purple potato tubers. Their structures were elucidated via 1D and 2D NMR and HR-ESI-MS and compared with those reported in the literature. The extracts were evaluated for anthocyanins and their derivatives using a tyrosinase inhibitor screening kit and molecular docking technology, and the results showed that petanin, norpetanin, 4-O-(p-coumaryl) rhamnose, and lyciruthephenylpropanoid D/E possessed tyrosinase inhibitory activity, with 50% inhibiting concentration (IC50) values of 122.37 ± 8.03, 115.53 ± 7.51, 335.03 ± 12.99, and 156.27 ± 11.22 μM (Mean ± SEM, n = 3), respectively. Furthermore, petanin was validated against melanogenesis in zebrafish; it was found that it could significantly inhibit melanin pigmentation (p < 0.001), and the inhibition rate of melanin was 17% compared with the normal group. This finding may provide potential treatments for diseases with abnormal melanin production, and high-quality raw materials for whitening cosmetics.

Sustainable Blue Foods from Rice-Animal Coculture Systems

Global interest grows in blue foods as part of sustainable diets, but little is known about the potential and environmental performance of blue foods from rice-animal coculture systems. Here, we compiled a large experimental database and conducted a comprehensive life cycle assessment to estimate the impacts of scaling up rice-fish and rice-crayfish systems in China. We find that a large amount of protein can be produced from the coculture systems, equivalent to ∼20% of freshwater aquaculture and ∼70% of marine wild capture projected in 2030. Because of the ecological benefits created by the symbiotic relationships, cocultured fish and crayfish are estimated to be carbon-negative (-9.8 and -4.7 kg of CO2e per 100 g of protein, respectively). When promoted at scale to displace red meat, they can save up to ∼98 million tons of greenhouse gases and up to ∼13 million hectares of farmland, equivalent to ∼44% of China's total rice acreage. These results suggest that rice-animal coculture systems can be an important source of blue foods and contribute to a sustainable dietary shift, while reducing the environmental footprints of rice production. To harvest these benefits, robust policy supports are required to guide the sustainable development of coculture systems and promote healthy and sustainable dietary change.

Water pollution scenarios and response options for China

China has formulated several policies to alleviate the water pollution load, but few studies have quantitatively analyzed their impacts on future water pollution loads in China. Based on grey water footprint (GWF) assessment and scenario simulation, we analyze the water pollution (including COD, NH3-N, TN and TP) in China from 2021 to 2035 under different scenarios for three areas: consumption-side, production-side and terminal treatment. We find that under the current policy scenario, the GWF of COD, NH3-N, TN, and TP in China could be reduced by 15.0 % to 39.9 %; the most effective measures for GWF reduction are diet structure change (in the consumption-side area), and the wastewater treatment rate and livestock manure utilization improvement (in the terminal treatment area). However, the GWF will still increase in 8 provinces, indicating that the current implemented policy is not universally effective in reducing GWF across all provinces. Under the technical improvement scenario, the GWF of the four pollutants will decrease by 54.9 %-71.1 % via improvements in the current measures related to current policies and new measures in the production-side area and the terminal treatment area; thus, GWF reduction is possible in all 31 provinces. However, some policies face significant challenges in achieving full implementation, and certain policies are only applicable to a subset of provinces. Our detailed analysis of future water pollution scenarios and response options to reduce pollution loads can help to inform the protection of freshwater resources in China and quantitatively assess the effectiveness of policies in other fields.

Dietary shifts drive the slowdown of declining methylmercury related health risk in China

Chinese population suffers severe health risk from dietary methylmercury (MeHg) exposure. However, the temporal change of such risk and socioeconomic driving factors remain unknown. This study investigates this issue by compiling time-series inventory of China's MeHg-related health risk at the provincial scale and revealing critical socioeconomic influencing factors through structural decomposition analysis. Results show that the per-fetus IQ decrements from dietary MeHg exposure have declined by 60% nationally during 2004-2019. Such decline results from the joint effects of dietary shifts (contributing 44%) and the decrease of MeHg concentrations in foods consumed (contributing 56%). However, the declining trend has slowed down since 2014 and even leveled off after 2016, which is mainly affected by dietary pattern changes. Especially, the increased intake level and proportion of fishes in underdeveloped provinces of China have dominated the slowdown of declining trend after 2016. Moreover, the affluence and education levels have significantly negative associations with per-fetus IQ decrements. Rich and well-educated people have higher ability of risk perception, which indicates the importance of rational consumption patterns. Our findings can help develop socioeconomic regulatory policies on reducing per-fetus IQ decrements from dietary MeHg exposure in China.

Enhanced food system efficiency is the key to China's 2060 carbon neutrality target

Bioenergy with carbon capture and storage, among other negative-emission technologies, is required for China to achieve carbon neutrality-yet it may hinder land-based Sustainable Development Goals. Using modelling and scenario analysis, we investigate how to mitigate the potential adverse impacts on the food system of ambitious bioenergy deployment in China and its trading partners. We find that producing bioenergy domestically while sticking to the food self-sufficiency ratio redlines would lower China's daily per capita calorie intake by 8% and increase domestic food prices by 23% by 2060. Removing China's food self-sufficiency ratio restrictions could halve the domestic food dilemma but risks transferring environmental burdens to other countries, whereas halving food loss and waste, shifting to healthier diets and narrowing crop yield gaps could effectively mitigate these external effects. Our results show that simultaneously achieving carbon neutrality, food security and global sustainability requires a careful combination of these measures.

Genome sequence analysis provides insights into the mode of 2n egg formation in Solanum malmeanum

KEY MESSAGE

Our genomic investigation confirms the mechanism of 2n eggs formation in S. malmeanum and aid in optimizing the use of wild germplasm. Wild potatoes are a valuable source of agronomic traits. However, substantial reproductive barriers limit gene flow into cultivated species. 2n gametes are instrumental in preventing endosperm abortion caused by genetic imbalances in the endosperm. However, little is known about the molecular mechanisms underlying the formation of 2n gametes. Here, the wild species Solanum malmeanum Bitter (2x, 1EBN, endosperm balance number) was used in inter- and intrapoloid crosses with other Solanum species, with viable seeds being produced only when S. malmeanum was used as the female parent to cross the 2EBN Solanum genus and with the likely involvement of 2n gametes. Subsequently, we substantiated the formation of 2n eggs in S. malmeanum using fluorescence in situ hybridization (FISH) and genomic sequencing technology. Additionally, the transmission rate of maternal heterozygous polymorphism sites was assessed from a genomic perspective to analyze the mode of 2n egg formation in S. malmeanum × S. tuberosum and S. malmeanum × S. chacoense crosses; each cross acquired an average of 31.12% and 22.79% maternal sites, respectively. This confirmed that 2n egg formation in S. malmeanum attributed to second-division restitution (SDR) coupled with the occurrence of exchange events. The high-throughput sequencing technology used in this study has strong advantages over traditional cytological analyses. Furthermore, S. malmeanum, which has a variety of excellent traits not available from present cultivated potato genepool, has received little research attention and has successfully achieved gene flow in cultivated species in the current study. These findings will facilitate the understanding and optimization of wild germplasm utilization in potatoes.

"Water-Carbon" redistribution caused by China's interprovincial grain transportation

Water resource and carbon emission involved in grain production in mainland China are redistributed among provinces as the grain was transported in recent years. This study first calculated the water consumption and carbon emission during the growth of grain crops based on the water-carbon footprint theory, and then used the social-equity method to calculate the inter-regional grain virtual water and virtual carbon flow. Finally, the regional and national trends in water saving and carbon emission reduction were calculated based on the spatial and temporal differences in grain planting among provinces. In terms of virtual water-carbon, from 2000 to 2017, the amount of the inter-provincial grain virtual water flow increased from 717.4 × 10⁸ m³ to 1472.6 × 10⁸ m³. Heilongjiang and Guangdong are the provinces with the largest amount of grain virtual water outflow (670.9 × 10⁸ m³) and inflow (402.8 × 10⁸ m³) in 2017, respectively. And the total inter-provincial grain virtual carbon flow increased from 2362.7 × 10⁴ t CO₂e to 12,680.6 × 10⁴ t CO₂e. Grain transport leads to water saving and carbon emission reduction, the amount of water saving increased from 25.6 × 10⁸ m³ to 77.0 × 10⁸ m³ and the carbon emission reduction increased from 2.4 × 10⁴ t CO₂e to 847.4 × 10⁴ t CO₂e from 2000 to 2017. Based on research results and from the perspective of socio-hydrology combined with water saving and carbon emission reduction, the regions could optimize the integration of water saving, carbon emission reduction, and sustainable development based on coordinating the grain planting structure according to their own climatic condition, soil and water resource condition, and socioeconomic condition.

Population growth of Tetranychus truncatus (Acari: Tetranychidae) on different drought-tolerant potato cultivars

Tetranychus truncatus Ehara (Acari: Tetranychidae) has become one of the major phytophagous pests in China in recent years, and is found on a wide range of host plants. However, little information is available on the population performance of this arthropod pest on potatoes. In this study, we explored the population growth of T. truncatus on two drought-tolerant potato (Solanum tuberosum L.) cultivars under laboratory conditions using the age-stage, two-sex life table. Tetranychus truncatus completed its entire life history on both potato cultivars tested, Holland 15 and Longshu 10. There was no significant difference between two potato cultivars in developmental duration. Tetranychus truncatus had shorter adult longevity (20.61 days), adult female longevity (20.41 days), and total female longevity (33.66 days) on Longshu 10 than Holland 15 (21.16 days, 21.19 days, and 34.38 days, respectively). However, it exhibited a higher preadult survival rate, higher fecundity (F = 88.32 eggs per female), and relatively higher population parameters when reared on Longshu 10 than on Holland 15 (F = 75.70 eggs per female). Growth projection also showed that the population size of T. truncatus on Longshu 10 (expand 750-fold) was larger than that on Holland 15 (expand 273-fold) after 60 days. Our results demonstrate that the drought-sensitive potato variety, Holland 15, is relatively resistant to T. truncatus compared with the drought-tolerant variety, Longshu 10, and suggest that T. truncatus exhibited a trade-off between longevity and reproduction on both potato cultivars. Our findings provide information on population prediction, which may aid the management of this pest mite species of potatoes.

The influences of the advancement of green technology on agricultural CO2 release reduction: A case of Chinese agricultural industry

The development of green technology (GT) may have a vital influence in decreasing carbon releases, and the linkage between the advancement of GT and CO2 releases in China's agricultural industry has not attracted enough attention. The main objectives of this study are to assess the influence of agricultural green technology advancement on efficiency enhancement, release control capabilities, agricultural energy structure, and agriculture industrial structure. This article decomposes the advancement of green technology (AGTP) in the agricultural industry in China into resource-saving green technology advancement (AEGTP) and emission reduction green technology advancement (ACGTP). At the same time, to evaluate the intermediary impact of green technology advancement, a two-step econometric model and an intermediary impact model were utilized to evaluate the panel data of 30 provinces in China from 1998 to 2018. The role of AGTP (including ACGTP and AEGTP) and CO2 release concentration has also been explored critically. The results show that (i) under the two-step measurement method, AGTP has substantial favorable impacts on agricultural energy efficiency (EF) and possesses a negative impact on agriculture industrial structure (PS) and agricultural energy structure (ES). Agricultural energy efficiency (EF) and agriculture industrial structure (PS) under AGTP will reduce CO2 release concentration, but the path of agricultural energy structure (ES) will increase CO2 release concentration. (ii) At the national level, AGTP has an immediate unfavorable influence on CO2 releases. After introducing the intermediary variables, the intermediary impact of AGTP on CO2 releases through agricultural energy efficiency (EF), agriculture industrial structure (PS), and agricultural energy structure (ES) is also significantly negative, and the direct impacts of each variable are higher than the intermediary impact. (iii) In terms of different zones, the direct impacts of AGTP are all significant. The order of significance of the direct impacts of different zones is west to central and central to eastern. The overall significance ranking of the mediating impact is ACGTP &gt; AEGTP &gt; AGTP, and the significance ranking of each index is ES &gt; EF &gt; PS. Finally, this article puts forward some policy recommendations to reduce CO2 releases.

Integrated biochar solutions can achieve carbon-neutral staple crop production

Agricultural food production is a main driver of global greenhouse gas emissions, with unclear pathways towards carbon neutrality. Here, through a comprehensive life-cycle assessment using data from China, we show that an integrated biomass pyrolysis and electricity generation system coupled with commonly applied methane and nitrogen mitigation measures can help reduce staple crops' life-cycle greenhouse gas emissions from the current 666.5 to -37.9 Tg CO₂-equivalent yr^-1. Emission reductions would be achieved primarily through carbon sequestration from biochar application to the soil, and fossil fuel displacement by bio-energy produced from pyrolysis. We estimate that this integrated system can increase crop yield by 8.3%, decrease reactive nitrogen losses by 25.5%, lower air pollutant emissions by 125-2,483 Gg yr^-1 and enhance net environmental and economic benefits by 36.2%. These results indicate that integrated biochar solutions could contribute to China's 2060 carbon neutrality objective while enhancing food security and environmental sustainability.

Bibliometrics of the nexus between food security and carbon emissions: hotspots and trends

With the growth of global food demand, agricultural carbon emissions caused by agricultural production have become a major challenge in controlling global warming. However, a systematic and visual literature review of food security and carbon emissions (FSCE) is still lacking, and there is a lack of exploration on the balanced path between ensuring food security and realizing carbon emission reduction. Based on 872 articles related to FSCE in the Web of Science (WOS) core database, this paper used CiteSpace and VOSviewer bibliometric software to analyze the relevant research focus and trends. This study found that developed countries dominated the research in this field, and the quantity, quality, and intensity of their authors, institutions, and cooperation among countries are higher than those of developing countries. Although the intensity of interdisciplinary cooperation has increased, it remains at a low level. Since 2007, the number of papers published in this field has increased significantly, and the research perspectives have diversified. Moreover, the research theme continues to expand with the core of "food security," involving the impact of climate change, crop production and food security, soil carbon sequestration, and farmers' livelihood sustainability. In addition, food production, food transportation, and food loss reduction are key paths that need to be balanced to ensure global food security and realize carbon emission reduction, and how to promote "economic growth" under the constraints of FSCE will be a future research hotspot.

Climate-smart planting for potato to balance economic return and environmental impact across China

Potato production plays an important role in safeguarding food security in China since the central government implemented the 'Potato-as-Staple-Food' policy in 2015. However, a key challenge facing China's potato production is to realize a tradeoff between economic return and environmental impact. Effective strategies for reducing carbon emission without compromising potato yield remain to be developed. This study conducted a comprehensive assessment by integrating climate, soil, crop, and agricultural input data, crop model and life cycle impact assessment model to quantify potato yields, GHG emission amounts and intensities (GHGI), and economic benefits under the conventional planting pattern (CPP), the lowest GHG emission pattern (LEP), and the highest yield pattern (HYP) across China's potato planting regions including four sub-regions, i.e., North Single planting region (NS), Central Double planting region (CD), South Winter planting region (SW), and Southwest Mixed planting region (SWM). Averaged fresh potato yield, GHG emission amount, and GHGI under the CPP were 21.7 t ha^-1, 2815.1 kg CO₂eq ha^-1, and 137.3 kg CO₂eq t^-1, respectively, in China's potato planting region. Compared with the CPP, averaged GHG emission amount and GHGI under the LEP could be decreased by 48.2 % and 51.5 % respectively while the fresh potato yield and economic benefit could be enhanced by 8.1 % and 18.5 %, respectively. For the HYP, averaged GHG emission amount and GHGI could be decreased by 24.2 % and 39.8 % respectively while the fresh potato yield and economic benefit could be enhanced by 18.7 % and 39.6 %, respectively, compared with the CPP. Across the four potato planting regions, SW had the largest potential in reducing GHG emissions owing to a high reduction amount of nitrogen application rate. Our study demonstrates that optimizing agronomic management could reduce environmental impact without compromising economic benefit and provides a scientific method for assessing crop potential to realize the climate-smart planting.

Towards cost-effective total pollution control in Chinese industries

The cost-effectiveness of the command-and-control policy instrument in environmental regulations has been debated for a long time. The aims of this study were to quantify the magnitude of the decline in the cost-effectiveness of the Regional Total Pollution Control (RTPC) policy, which includes mandatory emission reduction goals for each province, and to determine factors affecting it. For this purpose, province-level and technology-specific marginal abatement cost curves were constructed for China's three key industries, that is, thermal power, iron and steel, and cement industries. The results show that the average decline in the cost-effectiveness in these industries based on the implementation of the RTPC policy during the 13th Five Year Plan is ∼2.55%. The magnitude of the decline slightly changes from 1.44% to 3.63% (90th percentile) when different emission reduction allocation strategies are selected for different provinces. The three main factors contributing to the decline in the cost-effectiveness are the strictness of the emission reduction goal, variance of unit abatement cost (UAC) of technology, and matching degree between the UAC and emission reduction goals based on the RTPC. The RTPC causes a relatively slight decline in the cost-effectiveness compared with the competitive market and therefore can be used for future policy design.

Closing Greenhouse Gas Emission Gaps of Staple Crops in China

China is facing the dual challenge of achieving food security and agricultural carbon neutrality. Developing spatially explicit crop emission profiles can help inform policy to mitigate agricultural greenhouse gases (GHGs), but previous life-cycle studies were conducted mostly at national and provincial levels. Here, we estimate county-level carbon footprint of China's wheat and maize production based on a nationwide survey and determine the contribution of different strategies to closing regional emission gaps. Results show that crop carbon footprint varies widely between regions, from 0.07 to 3.00 kg CO₂e kg^-1 for wheat and from 0.09 to 2.30 kg CO₂e kg^-1 for maize, with inter-county variation generally much higher than interprovince variation. Hotspots are mainly concentrated in Xinjiang and Gansu provinces, owing to intensive irrigation and high plastic mulch and fertilizer inputs. Closing the regional emission gaps would benefit mostly from increasing crop yields and nitrogen use efficiency, but increasing manure use (e.g., in Northeast, East, and Central China) and energy use efficiency (e.g., in North and Northwest China) can also make important contributions. Our county-level carbon footprint estimates improve upon previous broad-scale results and will be valuable for detailed spatial analysis and the design of localized GHG mitigation strategies in China.

Conversion sweet sorghum biomass to produce value-added products

Currently, most biotechnological products are produced from sugar- or starch-containing crops via microbial conversion, but accelerating the conflict with food supply. Thus, it has become increasingly interesting for industrial biotechnology to seek alternative non-food feedstock, such as sweet sorghum. Value-added chemical production from sweet sorghum not only alleviates dependency and conflict for traditional starch feedstocks (especially corn), but also improves efficient utilization of semi-arid agricultural land resources, especially for China. Sweet sorghum is rich in components, such as fermentable carbohydrates, insoluble lignocellulosic parts and bioactive compounds, making it more likely to produce value-added chemicals. Thus, this review highlights detailed bioconversion methods and its applications for the production of value-added products from sweet sorghum biomass. Moreover, strategies and new perspectives on improving the production economics of sweet sorghum biomass utilization are also discussed, aiming to develop a competitive sweet sorghum-based economy.

Effect of Microwave Heat Processing on Nutritional Indices, Antinutrients, and Sensory Attributes of Potato Powder-Supplemented Flatbread

This study aims at evaluating nutritional, toxicological, and sensory attributes of microwave heat-treated potato powder-supplemented unleavened flatbread. Straight-grade wheat flour (SGF) was substituted with potato powder at the rate of 2.5–10% d.w. A comparison was made for nutritional, antinutrient, and organoleptic attributes of microwave heat-treated potato powder and SGF—potato powder composite flour-based flatbreads. The results suggest processed potato powder supplementation in SGF to significantly ( $p<0.05$ ) improve ash (0.48 to 0.63 g/100 g), dietary fiber (2.15 to 2.61 g/100 g), and protein (8.33 to 9.91 g/100 g) contents of composite chapatis. Likewise, significant ( $p<0.05$ ) improvement in the concentration of microelements and trace elements was observed including Ca, Na, K, Fe, and Zn contents, which were increased from 29.7 to 33.5 mg/100 g, 2.8 to 6.3 mg/100 g, 376 to 466 mg/100 g, 3.1 to 3.4 mg/100 g, and 3.17 to 3.25 mg/100 g, respectively. Microwave heating of potato powder was observed to reduce the load of alkaloids, oxalates, tannins, and phytates of the raw potato powder at the rate of 76%, 80%, 84%, and 82%, respectively, thus anticipating a promising response to minimize toxicant load in supplemented flatbread. Supplementing potato powder in SGF elucidated significant ( $p<0.05$ ) improvement in color values, i.e., a∗ (1.89–2.32) and b∗ (10.95–13.22), and increased product hardness from 3.17 to 7.9 N. The study concludes that microwave heat-treated potato powder yield improved nutritional and safety concerns of the consumers when used alone or as a supplement for developing composite flours based on value-added products.