Addressing China's grand challenge of achieving food security while ensuring environmental sustainability

Constructing a composite index to evaluate multidimensional variations in food security over different regions

Understanding food security level on a large scale is crucial for grasping global food security and issuing timely warnings about regional food systems risks. Current regional spatiotemporal distribution and multidimensional comparisons of global food security are insufficient. Therefore, this paper proposed a weighting technique combing the subjective AHP method with the objective CRITIC method, and developed a new composite index to measure food security multidimensionally. Using the food security composite index (FSCI), this study explored the spatiotemporal evolution of food security in different dimensions at both global and regional levels, based on panel data from 2001 to 2020. The variation of FSCI remained stable in the quantity dimension across all regions, with significant improvements in economic security observed in Europe and Latin America and Caribbean, and Asia showed an upward trend in resource dimension. Compared to the global average, Europe had a pronounced advantage, whereas Sub-Saharan Africa had a significant disadvantage.

Can internet use promote farmers to adopt chemical fertilizer reduction and efficiency enhancement technology in China?-an empirical analysis based on endogenous switching probit model

This study examines the impact of internet usage on farmer's adoption behavior of fertilizer reduction and efficiency enhancement technologies in China. Based on 1,295 questionnaires in Henan Province, this study constructs a counterfactual analysis framework and used endogenous switching probit model to analyze the effects and pathways of internet usage on farmer's adoption behavior of chemical fertilizer reduction and efficiency enhancement technologies. The results indicate that. (1) The proportion of farmers adopting chemical fertilizer reduction and efficiency enhancement technologies is 60.15%, while the proportion of farmers not adopting these technologies is 39.85%. (2) Internet usage directly influences farmers' adoption of fertilizer reduction and efficiency enhancement technologies. According to counterfactual assumption analysis, if farmers who currently use the Internet were to stop using it, the probability of them adopting these technologies would decrease by 28.09%. Conversely, for farmers who do not currently use the Internet, if they were to start using it, the probability of them adopting fertilizer reduction and efficiency enhancement technologies would increase by 40.67%. (3) Internet usage indirectly influences farmers' adoption behavior through mediating pathways of expected benefits and risk perception. In addition, social networks negatively moderate the impact of internet usage on farmers' behavior of chemical fertilizer reduction and efficiency enhancement technologies.

The elite haplotype OsGATA8-H coordinates nitrogen uptake and productive tiller formation in rice

Excessive nitrogen promotes the formation of nonproductive tillers in rice, which decreases nitrogen use efficiency (NUE). Developing high-NUE rice cultivars through balancing nitrogen uptake and the formation of productive tillers remains a long-standing challenge, yet how these two processes are coordinated in rice remains elusive. Here we identify the transcription factor OsGATA8 as a key coordinator of nitrogen uptake and tiller formation in rice. OsGATA8 negatively regulates nitrogen uptake by repressing transcription of the ammonium transporter gene OsAMT3.2. Meanwhile, it promotes tiller formation by repressing the transcription of OsTCP19, a negative modulator of tillering. We identify OsGATA8-H as a high-NUE haplotype with enhanced nitrogen uptake and a higher proportion of productive tillers. The geographical distribution of OsGATA8-H and its frequency change in historical accessions suggest its adaption to the fertile soil. Overall, this study provides molecular and evolutionary insights into the regulation of NUE and facilitates the breeding of rice cultivars with higher NUE.

Development and implementation of a novel mechanized planting method for ecological restoration of aquatic environments using degradable nutrition pots

Submerged plants play a significant role in the remediation and purification of polluted water bodies. Reconstruction of submerged plants has been considered as an important ecological method to restore aquatic ecosystems. However, large-scale and efficient plantation of submerged plants in water restoration is a huge challenge. This paper proposes a novel mechanized planting method for submerged plants utilizing nutrition pots as planting units. Firstly, the details of the mechanized planting method were introduced. The mechanized planting method involves pre-planting the reproductive bodies of submerged plants in degradable nutrition pots, and then implanting them into the underwater soil through a planting device. Secondly, the interaction force between the nutrition pot and the soil was measured. It was found that the implantation force of nutrition pots increases with planting velocity. The planting force shows a significant increase trend when the water content in the soil decreases. Thirdly, the deformation of the nutrition pot was studied through simulations. It was discovered that the deformation of the nutrition pot mainly occurs at the bottom and the side walls near the bottom, and the limited deformation ensures the integrity of the nutrition pot. Finally, a planting device with a linear motion mechanism was designed, and a typical submerged plant, Vallisneria natans was tested, using agricultural paper seedling containers as the nutrition pots. It was demonstrated that the mechanized device successfully planted submerged plant nutrition pots into the soil, and the submerged plants survived and showed a clear growth trend. The mechanized planting method of submerged plants proposed in this article is expected to provide a new and friendly technology for ecological restoration of water source.

Catalyzing sustainable development: Exploring the interplay between access to clean water, sanitation, renewable energy and electricity services in shaping China's energy, economic growth, and environmental landscape

The Sustainable Development Goals (SDGs) reflect the shift in global economic conversation toward inclusive growth. The growth can promote inclusivity and widespread sharing of its advancements by concentrating on four key dimensions. (a) Equality of opportunity, (b) sharing prosperity, (3) environmental sustainability/climate adaptation, and (4) macroeconomic stability. We used the Kao cointegration test to study how certain variables are connected over a long period. The relationship between CO2 and GDP per capita, renewable energy and tourism, improved water and sanitation, and access to power all have a positive feedback effect on each other. Based on FMOLS's findings, a 1 % increase in Inclusive growth leads to a 0.342 % (Model 1) and 0.258 % (Model 3) increase in CO2 emissions. An increase of 1 percent in energy consumption per person resulted in a rise of 1.343 % in CO2 emissions in Case 1, 0.524 % in Case 2, and 0.618 % in Case 3. Increasing the tourism sector's proportion of total exports by just one percent will reduce CO2 emissions by 0.221 % (case 1) and 0.234 % (case 3). Based on CCR findings, a 1 % improvement in inclusive growth leads to a 0.403.

Engineered Sustainable Omniphobic Coatings to Control Liquid Spreading on Food-Contact Materials

The adhesion of sticky liquid foods to a contacting surface can cause many technical challenges. The food manufacturing sector is confronted with many critical issues that can be overcome with long-lasting and highly nonwettable coatings. Nanoengineered biomimetic surfaces with distinct wettability and tunable interfaces have elicited increasing interest for their potential use in addressing a broad variety of scientific and technological applications, such as antifogging, anti-icing, antifouling, antiadhesion, and anticorrosion. Although a large number of nature-inspired surfaces have emerged, food-safe nonwetted surfaces are still in their infancy, and numerous structural design aspects remain unexplored. This Review summarizes the latest scientific research regarding the key principles, fabrication methods, and applications of three important categories of nonwettable surfaces: superhydrophobic, liquid-infused slippery, and re-entrant structured surfaces. The Review is particularly focused on new insights into the antiwetting mechanisms of these nanopatterned structures and discovering efficient platform methodologies to guide their rational design when in contact with food materials. A detailed description of the current opportunities, challenges, and future scale-up possibilities of these nanoengineered surfaces in the food industry is also provided.

Effects of straw returning combined with blended controlled-release urea fertilizer on crop yields, greenhouse gas emissions, and net ecosystem economic benefits: A nine-year field trial

Although straw returning combined with blended controlled-release urea fertilizer (BUFS) has been shown to improve wheat-maize rotation system productivity, their effects on greenhouse gas (GHG) emissions, carbon footprints (CF), and net ecosystem economic benefits (NEEB) are still unknown. Life cycle assessment was used to investigate a long-term (2013-2022) wheat-maize rotation experiment that included straw combined with two N fertilizer types [BUFS and (conventional urea fertilizer) CUFS] and straw-free treatments (BUF and CUF). The results showed that BUFS and CUFS treatments increased the annual yield by 13.8% and 11.5%, respectively, compared to BUF and CUF treatments. The BUFS treatment increased the yearly yield by 13.8% compared to the CUFS treatment. Since BUFS and CUFS treatments increased soil organic carbon (SOC) sink sequestration by 25.0% and 27.0% compared to BUF and CUF treatments, they reduced annual GHG emissions by 7.1% and 4.7% and CF per unit of yield (CFY) by 13.7% and 9.6%, respectively. BUFS treatment also increased SOC sink sequestration by 20.3%, reduced GHG emissions by 10.7% and CFY by 23.0% compared to CUFS treatment. It is worth noting that the BUFS and CUFS treatments increased the annual ecological costs by 41.6%, 26.9%, and health costs by 70.1% and 46.7% compared to the BUF and CUF treatments, but also increased the net yield benefits by 9.8%, 6.8%, and the soil nutrient cycling values by 29.2%, 27.3%, and finally improved the NEEB by 10.1%, 7.3%, respectively. Similar results were obtained for the BUFS treatment compared to the CUFS treatment, ultimately improving the NEEB by 23.1%. Based on assessing yield, GHG emissions, CF, and NEEB indicators, the BUFS treatment is recommended as an ideal agricultural fertilization model to promote sustainable and clean production in the wheat-maize rotation system and to protect the agroecological environment.

Farmland protection and fertilization intensity: Empirical evidence from preservation policy of Heilongjiang's black soil

The preservation of cultivated land quality stands as a vital prerequisite for ensuring food security and sustainability. In the black soil area of northeast China, a large amount of fertilizer was used to stabilize grain production in its early stages, which damaged soil structure and polluted the ecological environment. Based on the panel data of fertilization intensity of 48 districts and counties in Heilongjiang Province from 2010 to 2020, this study takes the implementation of the "Three-Year Action Plan for the Protection of Black Soil Farmland in Heilongjiang Province for the (2018-2020)" (TYAP) policy as a natural experiment, and uses the difference-in-differences (DiD) method to identify the causal effect of the policy on the local fertilization intensity. The results of the empirical study showed that the implementation of the TYAP policy significantly reduced the fertilization intensity of the black soil cultivated land implemented by the policy during the implementation period, which resulted in a decrease of 11.97% on average compared with the areas without the policy implementation. Several robustness tests provided additional confirmation of the aforementioned findings. This study further revealed that the policy mitigated fertilization intensity by fostering advancements in agricultural mechanization.

Construction of China's food security evaluation index system and spatiotemporal evolution

Food security is a vital material foundation for a nation's development and has been a topic of significant concern on the international stage in recent years. With a population exceeding 1.4 billion, China is not only a major producer but also a substantial consumer of food. Ensuring food security in China is not only a top priority for its socio-economic development but also a driving force in maintaining the stability of the global food supply chain and reducing the number of hungry people worldwide. However, a lack of comprehensive research into the Chinese food security system remains. This study addresses this gap by constructing a comprehensive evaluation framework encompassing four dimensions: food supply, accessibility, production stability, and sustainability. Utilizing the Moran's Index and generating LISA (Local Indicators of Spatial Association) maps, we analyze the spatial correlations of food security. The Dagum Gini coefficient and kernel density estimation are applied to assess heterogeneity and spatial disparities. Furthermore, this research employs the Exponential Smoothing (ETS) model to forecast food security trends. The findings reveal that the overall composite food security score exhibited fluctuations, initially increasing and reaching its peak of 0.407 in 2003, followed by a subsequent sharp decline after 2019. Spatially, food security exhibits correlations, with the Huang-Huai-Hai Plain and Northeast regions consistently showing high-high clustering. In contrast, the Western and Southern regions exhibit low-low clustering at specific periods. The Dagum Gini coefficient indicates that overall food security disparities are relatively small. However, these disparities have gradually expanded in recent years, with inter-group differences becoming predominant after 2005. As indicated by the kernel density estimation, the dynamic distribution of food security initially widens and then narrows, suggesting a shift from dispersed to concentrated data distribution. This phenomenon is accompanied by polarization and convergence trends, particularly evident after 2015. According to the ETS model, the study forecasts a substantial risk of declining food security in China over the next decade, largely influenced by the ongoing pandemic. In conclusion, this research provides a comprehensive assessment of the changing status of food security in China. It offers early warnings through predictive analysis, addressing the existing research gaps in the field of food security.

Long-term trajectory of ozone impact on maize and soybean yields in the United States: A 40-year spatial-temporal analysis

Understanding the long-term change trends of ozone-induced yield losses is crucial for formulating strategies to alleviate ozone damaging effects, aiming towards achieving the Zero Hunger Sustainable Development Goal. Despite a wealth of experimental research indicating that ozone's influence on agricultural production exhibits marked fluctuations and differs significantly across various geographical locations, previous studies using global statistical models often failed to capture this spatial-temporal variability, leading to uncertainties in ozone impact estimation. To address this issue, we conducted a comprehensive assessment of the spatial-temporal variability of ozone impacts on maize and soybean yields in the United States (1981-2021) using a geographically and temporally weighted regression (GTWR) model. Our results revealed that over the past four decades, ozone pollution has led to average yield losses of -3.5% for maize and -6.1% for soybean, translating into an annual economic loss of approximately $2.6 billion. Interestingly, despite an overall downward trend in ozone impacts on crop yields following the implementation of stringent ozone emission control measures in 1997, our study identified distinct peaks of abnormally high yield reduction rates in drought years. Significant spatial heterogeneity was detected in ozone impacts across the study area, with ozone damage hotspots located in the Southeast Region and the Mississippi River Basin for maize and soybean, respectively. Furthermore, we discovered that hydrothermal factors modulate crop responses to ozone, with maize showing an inverted U-shaped yield loss trend with temperature increases, while soybean demonstrated an upward trend. Both crops experienced amplified ozone-induced yield losses with rising precipitation. Overall, our study highlights the necessity of incorporating spatiotemporal variability into assessments of crop yield losses attributable to ozone pollution. The insights garnered from our findings can contribute to the formulation of region-specific pollutant emission policies, based on the distinct profiles of ozone-induced agricultural damage across different regions.

Food-energy-water nexus optimization brings substantial reduction of urban resource consumption and greenhouse gas emissions

Urban sustainability is a key to achieving the UN sustainable development goals (SDGs). Secure and efficient provision of food, energy, and water (FEW) resources is a critical strategy for urban sustainability. While there has been extensive discussion on the positive effects of the FEW nexus on resource efficiency and climate impacts, measuring the extent to which such synergy can benefit urban sustainability remains challenging. Here, we have developed a systematic and integrated optimization framework to explore the potential of the FEW nexus in reducing urban resource demand and greenhouse gas (GHG) emissions. Demonstrated using the Metropolis Beijing, we have identified that the optimized FEW nexus can reduce resource consumption and GHG emissions by 21.0 and 29.1%, respectively. These reductions come with increased costs compared to the siloed FEW management, but it still achieved a 16.8% reduction in economic cost compared to the business-as-usual scenario. These findings underscore the significant potential of FEW nexus management in enhancing urban resource efficiency and addressing climate impacts, while also identifying strategies to address trade-offs and increase synergies.

Balancing potato yield, soil nutrient supply, and nitrous oxide emissions: An analysis of nitrogen application trade-offs

Potato has been promoted as a national key staple food to alleviate pressure on food security in China. Appropriate nitrogen (N) application rate is prerequisite and is crucial for increasing yield, improving fertilizer efficiency, and reducing N losses. In the present study, we determined the optimum N application rates by analyzing field trial data from the main potato producing areas of China between 2004 and 2020. We considered the equilibrium relationships between potato yield, N uptake, partial N balance (PNB), and N2O emission under different soil indigenous N supply (INS) scenarios. The results showed that N rate, INS, and their interactions all significantly affect potato yield and nutrient uptake increment. On average, N application increased potato yield and N uptake by 29.5 % and 56.7 %, respectively. The relationship between N rate and yield increment was linear-plateau, while the relationship between N rate and N uptake increment was linear-linear. Soil INS accounted for 63.5 % of total potato N requirement. Potato yield increment and nutrient uptake increment were exponentially negatively correlated with INS and had a significant parabolic-nonlinear relationship with the interaction of N fertilizer application rate and INS. PNB was negatively correlated with fertilizer N supply intensity as a power function. Based on our analysis, a N application rate of 166 kg N ha-1 was found to be sufficient when the target yield was <34 t ha-1. However, when the target yield reached 40, 50 and 60 t ha-1, the recommended N application rate increased to 182, 211, and 254 kg N ha-1, respectively, while ensuring N2O emissions low with an emission factor of 0.2 %. Our findings will help guide potato farming toward cleaner production without compromising environmental benefit.

Towards sustainable management of agricultural resources: A framework to assess the relationship between water, soil, economic factors, and grain production

As the requirements for environmental protection and high-efficiency economies increase, grain production (GP) across the globe faces more stringent ecological constraints and economic pressure. Understanding the relationships between natural resources and economic and agricultural factors in grain-producing regions is paramount for ensuring global food security. This paper proposes a methodological framework to explore the relationships between water and soil resources (WSRs), economic input factors (EIFs), and GP. We employed the northeast region of China as a case study to advance our understanding of the factors driving the development of grain-producing capacity. We first constructed and calculated the region's water and soil comprehensive index (WSCI) to describe water-soil properties. We then used hotspot analysis to explore the spatial agglomeration characteristics of WSRs, EIFs, and GP. Finally, we used threshold regression analysis to understand the effects of EIFs and GP with the WSCI as the threshold variable. With the improvement of the WSCI, the positive impact of fertilizer and irrigation on GP shows a U-shaped curve in elasticity coefficients. The positive effect of agricultural machinery on GP decreases significantly, and the impact of labor input on GP is insignificant. These results provide new insights into the relationship between WSRs, EIFs, and GP and a reference for improving GP efficiency globally. This work thus contributes to advancing our capabilities to enable food security while considering aspects of sustainable agriculture in important grain-producing regions across the globe.

Sustainable poverty reduction models for the coordinated development of the social economy and environment in China

Sustainable development in impoverished areas is still a global challenge owing to trade-offs between development and conservation. There are large poverty-stricken areas (PSAs) in China, which overlap highly with ecologically sensitive areas. China has made great efforts to alleviate poverty over the years. The coordinated relationship between the social economy and the environment in PSAs, however, remains under-recognized. This study developed a county-level index system encompassing the socioeconomic and environmental sectors of China's PSAs. The integrated indexes of the two sectors were developed to reveal the spatial-temporal socioeconomic and environmental patterns and coupling coordination degree (CCD) levels were calculated to assess the coordinated relationships between them. The CCD indicated the increasingly coordinated development of socioeconomic and environmental conditions in China's PSAs from 2000 to 2020. Meanwhile, although the socioeconomic index achieved considerable growth with a growth rate of 58.4%, the environmental index was mildly improved with a growth rate of 19.6%, instead of a reduction. PSAs still have a large gap in socioeconomic development compared to non-poor areas; however, PSAs perform better in environmental index. Overall, the increased coordinated development between the social economy and the environment from 2000 to 2020 can be attributed to China's long-term, large-scale, and targeted interventions in poverty reduction and environmental conservation. Further, benefiting from the geodiversity of China, we identified four poverty reduction models which include advantageously, sustained, periodic, and limited effective models, on the basis of CCD change patterns. The four models can provide valuable experience for the rest of the world in tackling similar trade-offs of poverty reduction and environmental challenges.

Food security and overuse of agrochemicals: evidence from China's major grain-producing areas policy

China's major grain-producing areas (MGPA) policy is the core policy to ensure national food security. While achieving long-term stable growth of grain production, assessing the impact of MGPA policy on agrochemical application has important practical significance in sustainable agricultural development and environmental protection. Based on panel data of 31 provinces in China from 1997 to 2020 and taking the MGPA policy introduced in 2004 as a quasi-natural experiment, we construct a difference-in-difference (DID) model to evaluate the overall impact and dynamic effect of MGPA policy. It is found that the MGPA policy do not exacerbate chemical overuse as a whole, but significantly reduce the fertilizer use by 11% and the pesticide use by 6%. Using the event study to decompose the policy effect year by year, we find that the MGPA policy significantly increased the fertilizer and pesticide use in a short period of time. Its influence on the application amount of two chemicals began to turn negative until the fourth and sixth years of the policy implementation and became more and more obvious. We conclude the intermediate paths of MGPA policy to change planting structure, deepen agricultural division of labor, and reduce the use of agrochemicals, which were verified by the intermediary effect model. From the perspective of provincial differences, MGPA policy reduced chemical use more in provinces with large output contribution and northern provinces. In addition, the MGPA policy has reduced the amount of fertilizer application in major rice-growing provinces, but not the amount of pesticide application. Our research can provide implications for other developing countries and emerging economies where agricultural production is highly dependent on chemicals and has green agricultural transition plans.

Impact assessment of surface ozone exposure on crop yields at three tropical stations over India

Surface ozone is a damaging pollutant for crops and ecosystems, and the ozone-induced crop losses over India remain uncertain and a topic of debate due to a lack of sufficient observations and uncertainties involved in the modeled results. In this study, we have used the observational data from MAPAN (Modelling Air Pollution And Networking) for the first time to estimate the relative yield losses, crop production losses, and economic losses for the two major crops (wheat and rice). The detailed estimation has been done focusing on three individual suburban sites over India (Patiala, Tezpur, and Delhi) and compared with other related studies over the Indian region. We have used the concentration-based metric (M7, 7-h average from 09:00 to 15:59 h) along with the cumulative ozone exposure indices (AOT40, accumulated exposure over a threshold of 40 ppb) and applied the exposure-response (E-R) functions for the calculation of the crop losses. Our study shows that the yearly crop losses can reach the level of 12.4-40.8% and 2.0-11.1% for the wheat and rice crops, respectively, at certain places like Patiala in India. The annual economic loss can be as high as $4.6 million and $0.7 million for wheat and rice crops, respectively, even at individual locations in India. Our estimated %RYL (relative yield loss) lies in the range of 0.3 + /0.6 times the recent regional model estimates which use only the AOT40 metric. Region-specific E-R functions based on factors suitable for the Indian region needs to be developed.

Sustainable decontamination of heavy metal in wastewater and soil with novel rectangular wave asymmetrical alternative current electrochemistry

A new concept of removal and recovery of heavy metals and simultaneous regeneration and reuse of ethylenediamine-tetraacetic acid (EDTA) in soil washing effluent containing metal-EDTA complexes is proposed, which is used to remediate heavy metal contaminated soil. To achieve this goal, soil washing approach coupled with rectangular wave asymmetrical alternative current electrochemistry (RW-ACE) equipped with amidoxime-functionalized electrodes (Ami-CF) is employed. With high hydrophilicity and strong binding affinity, Ami-CF could specifically compete for heavy metals over EDTA under electric field. RW-ACE system is found successfully to achieve the non-destructive decomplexation of heavy metal-EDTA, and then regenerate EDTA for highly recycling, which saves as high as 98.9 % EDTA consumption compared with conventional washing method. Moreover, more than 90% of heavy metals are recovered and deposited on the electrode with a majority of them existed as zero-valence state as evidenced by XPS. The RW-ACE method is universal for various heavy metals such as Cu²⁺, Zn²⁺, Cd²⁺, and Pb²⁺ in an authentic contaminated soil, and the loss of soil nutrient is very limited. Along with long-term assessment and operation cost estimation, the RW-ACE method is a sustainable remediation approach for the heavy metal polluted wastewater and soils, and easily scaled up for field practice.

Does economic agglomeration improve agricultural green total factor productivity? Evidence from China's Yangtze river delta

Economic agglomeration plays an important role in China's social transformation process of industry feeding agriculture and urban supporting rural areas, and is one of the core weapons to promote agricultural economic growth and green and efficient development. Based on panel data of 41 cities in the Yangtze River Delta (YRD) from 2010 to 2020, this paper constructs an "environment-resource-energy-economy" agricultural input-output system, taking into account carbon emissions and surface pollution, and provides a more comprehensive accounting of agricultural green total factor productivity (AGTFP), the non-linear effects of economic agglomeration on AGTFP and shock responses were empirically analyzed using a panel threshold model and a panel vector autoregression (VAR), respectively. The findings show that: (1) during the period 2010-2020, the AGTFP in the YRD showed an overall rising trend with regional spatial agglomeration characteristics. (2) Economic agglomeration has a triple threshold effect on AGTFP, which was a weak facilitative effect in the early stage, inhibited by the siphoning effect of resource loss and arable land fragmentation in the growth stage, promoted by the radiation effect of external increasing return to scale in the form of sharing, matching and learning in the maturity stage, and finally tends to decline. (3) The shock response of economic agglomeration to AGTFP showed a continuous positive shock, peaking in the first period and then gradually converging to zero. (4) The heterogeneity analysis demonstrated that economic agglomeration has a considerable impact on boosting AGTFP in non-metropolitan areas and cities on the outskirts of YRD. In the future, China should effectively play a positive role in economic agglomeration on AGTFP and enhance the mutual coordination of economic agglomeration and agricultural green development in the process of urban cluster economic growth.

Comprehensive QTL analyses of nitrogen use efficiency in indica rice

Nitrogen-use efficiency (NUE) in rice is a complex quantitative trait involved in multiple biological processes and agronomic traits; however, the genetic basis and regulatory network of NUE remain largely unknown. We constructed a high-resolution microarray-based genetic map for 261 recombinant inbred lines derived from two indica parents. Using 2,345 bin markers, comprehensive analyses of quantitative trait loci (QTLs) of seven key agronomic traits under two different N levels were performed. A total of 11 non-redundant QTLs for effective panicle number (EPN), 7 for grain number per panicle, 13 for thousand-grain weight, 2 for seed-setting percentage, 15 for plant height, 12 for panicle length, and 6 for grain yield per plant were identified. The QTL regions were as small as 512 kb on average, and more than half spanned an interval smaller than 100 kb. Using this advantage, we identified possible candidate genes of two major EPN-related QTLs. One QTL detected under both N levels possibly encodes a DELLA protein SLR1, which is known to regulate NUE, although the natural variations of this protein have not been reported. The other QTL detected only under a high N level could encode the transcription factor OsbZIP59. We also predicted the possible candidate genes for another three of the NUE-related QTLs. Our results provide a reference for improving NUE-related QTL cloning and promote our understanding of NUE regulation in indica rice.

Exolaccase-boosted humification for agricultural applications

Globally, phenolic contaminants have posed a considerable threat to agro-ecosystems. Exolaccase-boosted humification may be an admirable strategy for phenolic detoxification by creating multifunctional humic-like products (H-LPs). Nonetheless, the potential applicability of the formed H-LPs in agricultural production is still overlooked. This review describes immobilized exolaccase-enabled humification in eliminating phenolic pollutants and producing artificial H-LPs. The similarities and differences between artificial H-LPs and natural humic substances (HSs) in chemical properties are compared. In particular, the agronomic effects of these reproducible artificial H-LPs are highlighted. On the basis of the above summary, the granulation process is employed to prepare granular humic-like organic fertilizers, which can be applied to field crops by mechanical side-deep fertilization. Finally, the challenges and perspectives of exolaccase-boosted humification for practical applications are also discussed. This review is a first step toward a more profound understanding of phenolic detoxification, soil improvement, and agricultural production by exolaccase-boosted humification.

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Exolaccase-initiated humification is conductive to phenolic detoxification

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Multiple humic-like products are created in exolaccase-boosted humification

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Similarities and differences between artificial and natural humus are disclosed

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Humic-like products can be used to sustain soil health and increase crop yield

Maps of cropping patterns in China during 2015-2021

Multiple cropping is a widespread approach for intensifying crop production through rotations of diverse crops. Maps of cropping intensity with crop descriptions are important for supporting sustainable agricultural management. As the most populated country, China ranked first in global cereal production and the percentages of multiple-cropped land are twice of the global average. However, there are no reliable updated national-scale maps of cropping patterns in China. Here we present the first recent annual 500-m MODIS-based national maps of multiple cropping systems in China using phenology-based mapping algorithms with pixel purity-based thresholds, which provide information on cropping intensity with descriptions of three staple crops (maize, paddy rice, and wheat). The produced cropping patterns maps achieved an overall accuracy of 89% based on ground truth data, and a good agreement with the statistical data (R2 ≥ 0.89). The China Cropping Pattern maps (ChinaCP) are available for public download online. Cropping patterns maps in China and other countries with finer resolutions can be produced based on Sentinel-2 Multispectral Instrument (MSI) images using the shared code.

Trends in climate, socioeconomic indices and food security in Nigeria: Current realities and challenges ahead

Food security in Nigeria is presently in dire strait owing to several factors, such as skyrocketing energy prices, climate change, and terrorism. This study is aimed at revealing the role of the aforementioned factors in shaping food affordability and availability in the country. The study used descriptive statistics and coefficients of variation and determination to ascertain the change in the trend in these factors and their correlates to food security over time. From the results of our research team, we inferred that temperature increases, political instability, rising food prices and erratic energy supply have had distressing consequences in the areas of affordability, availability and stability of food supplies. We conclude that a rapidly growing population such as Nigeria's would need crucial interventions in increasing food production, mitigating the impacts of climate change, and buffering energy supplies. Ultimately, Nigeria needs to overhaul the important components of her food systems and the respective linkages between these components in order to ensure food security for the entire population.

A New Framework of Green Transition of Cultivated Land-Use for the Coordination among the Water-Land-Food-Carbon Nexus in China

As a fundamental solution to the ecological problems of resources and environment, the Green Transition of Cultivated Land-use (GTCL) has become an inherent requirement for promoting ecological progress and implementing the food security strategy in the new era. This paper proposed a theoretical framework of GTCL and constructed a GTCL development index system based on four aspects: water, land, food and carbon; then, by applying a comprehensive evaluation model, a coupling coordination model and exploratory spatial data analysis, the development level of GTCL in China’s 31 provinces, municipalities and autonomous regions in 2000, 2005, 2010, 2015 and 2020 was evaluated and the spatial and temporal rates of change of “water, land, food and carbon” (WLFC) and their coupling coordination were finally analyzed to reveal the “water, land, food and carbon” effect of GTCL. Results showed that the systemic changes of WLFC and its coupling coordination degree of GTCL presented a spatial and temporal coincidence with a high degree of consistency; from 2000 to 2020, the overall GTCL rate in all Chinese provinces, municipalities and autonomous regions showed a “W”-shaped fluctuation uptrend. In the past five years, the development level of GTCL was higher in Northeast China, followed by Central China and North China, while South China was at a low level. In addition, WLFC showed a more obvious “W”-shaped fluctuation, with higher coupling coordination in Northeast China in good coordination and lower coordination in East China and Southwest China. Therefore, according to the results of the study, areas were divided into: benefit leading area, quality improvement area, connotation tapping potential area, ductile development area and ecological reserve area for the regulation of GTCL in all Chinese provinces, municipalities and autonomous regions.

Digital Economy, Agricultural Technological Progress, and Agricultural Carbon Intensity: Evidence from China

China is the largest carbon emitter in the world, with agricultural carbon emissions accounting for 17% of China’s total carbon emissions. Agricultural carbon emission reduction has become the key to achieving the “Double Carbon” goal. At the same time, the role of the digital economy in achieving the “dual carbon” goal cannot be ignored as an important engine to boost the high-quality development of China’s economy. Therefore, this paper uses the panel data of 30 provinces in mainland China from 2011 to 2019 to construct a spatial Durbin model and a mediation effect model to explore the impact of the digital economy on agricultural carbon intensity and the mediating role of agricultural technological progress. The research results show that: (1) China’s agricultural carbon intensity fluctuated and declined during the study period, but the current agricultural carbon intensity is still at a high level; (2) The inhibitory effect of the digital economy on agricultural carbon intensity is achieved by promoting agricultural technological progress, and the intermediary role of agricultural technological progress has been verified; (3) The digital economy can significantly reduce the carbon intensity of agriculture, and this inhibition has a positive spatial spillover effect. According to the research conclusions, the government should speed up the development of internet technology and digital inclusive finance, support agricultural technology research and improve farmers’ human capital, and strengthen regional cooperation to release the contribution of digital economy space.

Spatial evolution of cultivated land in the Heilongjiang Province in China from 1980 to 2015

Sustaining cultivated land is critically important for food security, economic development, and social stability in China. China has been developing rapidly since the adoption of the Chinese Economic Reform of 1978, revealing the spatial evolution characteristics of cultivated land can provide valuable information for estimating and sustaining Chinese food security. In this study, we analyzed the spatial evolution of cultivated land from 1980 to 2015 in the Heilongjiang Province, one of the most important grain production regions in China, by combining five land-use databases, a geographic information system, and mathematical models. The results showed that cultivated land in the Heilongjiang Province increased by 33,234 km² (23%) from 1980 to 2015. The increase primarily resulted from land conversion from the forest (11,511 km²), grassland (9780 km²), and unused land (9696 km²). Additionally, cultivated land-use change's spatial characteristics differed among decadal periods. Spatial changes were stronger during 1990-2000 than in the other periods (1980-1990, 2000-2010, and 2010-2015). The landscape shape index indicated that cultivated land development had a regular changing pattern but showed a trend toward irregular development over the study period. The spatial expansion of cultivated land showed a strong directional trend, which was further found to be associated with geomorphological factors, indicating the prominent controls of abiotic factors on cultivated land expansion. This study provides an overview of the long-term spatial evolution characteristics of cultivated land and the key abiotic controls on cultivated land use change. This information can help local government policymakers effectively balance regional development, environmental protection, and food security.

Analysis on the spatio-temporal evolution and influencing factors of China's grain production

The rapid economic development and climate change have accelerated the changes in China's food production and have a potential impact on food security. In this paper, the grain sown area from 2001 to 2019 was selected to analyze the spatio-temporal evolution and driving factors of China's grain production through spatial autocorrelation analysis and geographically weighted regression. Our findings were as follows: (1) From the perspective of time characteristics, China's grain production from 2001 to 2019 experienced four stages, rapid decline, rapid growth, steady growth, and slow decline, although with an overall upward trend. (2) From the perspective of spatial characteristics, the overall spatial pattern had a significant positive correlation. The high values were mainly concentrated in Shandong, Anhui, and Jilin and moved to the northeast China as time went on. (3) In terms of influencing factors, the positive impact of agricultural labor force on the grain production gradually decreased, showing a decreasing trend from southwest to northeast. The promotion of agricultural mechanization on the grain production increased year by year, with the spatial distribution characteristics of high in the northeast and low in the southwest. Besides, the coefficient of water resources endowment was negative, showing a spatial distribution pattern of high north and low south.

Large spatial variation and stagnation of cropland gross primary production increases the challenges of sustainable grain production and food security in China

Sustainable crop grain production and food security is a grand societal challenge. Substantial investments in China's agriculture have been made in the past decades, but our knowledge on cropland gross primary production in China remains limited. Here we analyzed gross primary production (GPP), solar-induced chlorophyll fluorescence (SIF), terrestrial water storage, crop grain production, and agricultural investment and policy during 2000-2018. We found that based on croplands in 2000, approximately 52 × 10⁶ ha (~37%) had continuous increasing trends in GPP during 2000-2018, which were mainly located in northern China. GPP for 63% of croplands was stagnant, declined, or had no significant change. At the national scale, annual cropland GPP increased during 2000-2008 but became stagnant in 2009-2018, which was inconsistent with the interannual trend in the crop grain production data for 2009-2018. The spatial mismatch between crop production and water availability became worse. The major grain exporting provinces, mostly located in water-stressed regions, experienced increased water resource constraints, which posed a challenge for sustainable grain production. The stagnant cropland GPP and increasing water resource constraints highlight the urgent need for sustainable management for crop production and food security in China.

Improved economic and environmental outcomes from targeted fertilizer policy

The overuse of nitrogen (N) fertilizer for wheat is a serious problem in China, and previous studies seldom distinguish between the use of basal and topdressing N fertilizer. Data from 225 households in Jiangsu Province, China (a wheat planting area), were collected through face-to-face interviews with each head of the household. Regression models were used to study factors affecting farmers' application of basal and topdressing N fertilizers separately. Fertilizer retailers proposed fertilizer application levels that were in opposition to their concern for the environment. Farmers' concern for the environment only affected their application of topdressing N fertilizer and had no significant influence for use of total N fertilizer. The farmland area and amount of experience planting wheat had negative effects on basal N fertilizer use, but not on topdressing fertilizer. In the study area, the optimal strategy for decreasing N fertilizer application is designing policies to rent more farmlands to farmers with the most experience first. These farmers with their higher farm income would decrease basal N fertilizer use and the basal-topdressing ratio to improve N fertilizer use efficiency and then decrease the N fertilizer leaching into the environment.

Controlling Non-Grain Production Based on Cultivated Land Multifunction Assessment

The control of non-grain production (NGP) has become a great challenge for cultivated land protection in China in recent years. A control method for NGP that can coordinate the conflicts between cultivated land protection and farmers’ interest is urgently needed. Taking Tongxiang City as an example, this research proposed a solution for the control and management of NGP based on cultivated land multifunctional assessment. The GIS and AHP approach were used to assess production function via a comprehensive evaluation index. The InVEST and FMSPA models were applied to assess ecological function while, the Maxent model was applied to assess recreational function, then multifunctional comprehensive zoning was conducted through natural breakpoint method and spatial overlay analysis. Five development-oriented function zones were considered, including the core area of grain production plus areas for ecological agriculture, leisure agriculture, compound agriculture, and general farmland. Differentiated control measures for NGPs in each functional subarea are proposed considering the current NGP distribution of Tongxiang city. This research can provide a reference for subsequent improvement of land management policies and can aid the achievement of sustainable agricultural development and rural revitalization.

Cropland redistribution to marginal lands undermines environmental sustainability

Cropland redistribution to marginal land has been reported worldwide; however, the resulting impacts on environmental sustainability have not been investigated sufficiently. Here we investigated the environmental impacts of cropland redistribution in China. As a result of urbanization-induced loss of high-quality croplands in south China (∼8.5 t ha-1), croplands expanded to marginal lands in northeast (∼4.5 t ha-1) and northwest China (∼2.9 t ha-1) during 1990-2015 to pursue food security. However, the reclamation in these low-yield and ecologically vulnerable zones considerably undermined local environmental sustainability, for example increasing wind erosion (+3.47%), irrigation water consumption (+34.42%), fertilizer use (+20.02%) and decreasing natural habitats (-3.11%). Forecasts show that further reclamation in marginal lands per current policies would exacerbate environmental costs by 2050. The future cropland security risk will be remarkably intensified because of the conflict between food production and environmental sustainability. Our research suggests that globally emerging reclamation of marginal lands should be restricted and crop yield boost should be encouraged for both food security and environmental benefits.

Exogenous application of melatonin to plants, algae, and harvested products to sustain agricultural productivity and enhance nutritional and nutraceutical value: A meta-analysis

Melatonin is produced by plants, algae, and animals. Worldwide studies show diverse positive effects of exogenous melatonin on plants, edible plant products, and algae, but the potential of melatonin to enhance food and feed systems through these positive effects remains largely unexplored. Through a meta-analysis of about 25,000 observations, we show for the first time that exogenous application of melatonin significantly increases crop productivity and yields, and enhances the nutritional and nutraceutical value of edible plant products and algae by regulating diverse biological functions. We demonstrate that melatonin can improve plants, edible plant products, and algae under various current climate change scenarios, environmental pollution factors, and other stresses by about 7% to nearly 30%, on average, depending on the stressor. We also analyze various technical/methodological factors influencing the desired outcomes and identify conditions that offer optimal enhancement. We show that the positive effect of melatonin on plants and edible plant products varies among species, genera, and families, and strongly depends on the concentration of melatonin and treatment duration. The effect of melatonin is slightly lower on the monocot clade Commelinids than on the eudicot clades Asterids and Rosids. We also show that its stimulatory effect on plants depends on cultivation system, with a larger effect obtained in hydroponic systems. However, it does not depend on application stage (seed or vegetative), application route (foliage, roots, or seed), and whether the cultivation system is ex vivo or in vivo. This is the first meta-analysis examining the effects of melatonin on plants, edible plant products, and algae, and offers a scientific and technical roadmap facilitating sustainable food and feed production through the application of exogenous melatonin.

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

China has recently implemented a policy to promote potato as a national staple food and to close its large yield gaps with other countries. The carbon-land-water implications of this policy are examined here by compiling and analysing detailed city-level life-cycle inventories of China's staple crops. We find that in general potato, despite relatively low yields, has lower greenhouse gas emissions and water demand than other staple crops (maize, wheat and rice) on a per-calorie basis, but substantial regional variation exists for each crop. Integrating potato as a staple in China to meet increases in food demand and close the yield gap has the potential to reduce the total carbon-land-water impacts of staple crops by 17-25% by 2030. However, an unsuccessful integration runs the risk of global burden-shifting if the policy, for example, reduced domestic rice production and led to increased rice imports. Potential synergies between food security and environmental sustainability in China can be created by the potato policy, but greater efforts are needed to promote potato across the entire food supply chain from production to consumption.

Surface mining caused multiple ecosystem service losses in China

China's surface mining greatly supported the rapid socio-economic development; however, there was a scarcity in the systematic understanding of national changes in surface mining changes and associated ecosystem services (ESs) losses, which inevitably affected human well-being and limited sustainable ecosystem management and policy optimization. In this study, we quantified the areal changes in surface mining based on the ChinaCover database and performed further analysis of ES loss from expanded surface mining using multidimensional geospatial data from 1990 to 2015, including MODIS products, meteorological records, and statistical datasets. Our observations reveal that China's surface mining was estimated to be 4746 km² in 2015 and that Inner Mongolia had the largest surface mining area (28%). Surface mining expanded remarkably from 1990 to 2015, with an increase by 2.7 times after 2000. In particular, Inner Mongolia, Shanxi, and Qinghai had the greatest increases in surface mining area. Rapid expansion of surface mining led to obvious declines in natural habitat area, water retention, net primary productivity, and grain production, and these ES losses showed apparent spatiotemporal variations. China has taken many measures to reclaim the abandoned surface mining sites. Given the rapid expansion of surface mining and related ES loss, China should continue to perform ecological restoration for its sustainability.

Risk assessment of insect pest expansion in alpine ecosystems under climate change

BACKGROUND

Growth in insect pest populations poses a significant threat to ecosystem functions and services, societal development, and food security in alpine regions under climate change. Risk assessments are important prioritization tools for pest management, which must be used to study insect pest expansion in alpine ecosystems under global warming. We used species distribution modeling to simulate the current and future distribution probabilities of 58 insect pest species in the Qinghai Province, China, based on a comprehensive field investigation. Subsequently, general linear modeling was used to explore the relationship between the distribution probability of these species and the damage caused by them. Finally, we assessed the ecological risk of insect pest expansion across different alpine ecosystems under climate change.

RESULTS

Climate change could increase the distribution probabilities of insect pest species across different alpine ecosystems. However, the presence of insect pest species may not correspond to the damage occurrence in alpine ecosystems based on percent leaf loss, amount of stunting, and seedling death of their host species. Significant positive relationships between distribution probability and damage occurrence were found for several of the examined insect pest species. Insect pest expansion is likely to increase extensively in alpine ecosystems under increasing carbon dioxide (CO₂ ) emission scenarios.

CONCLUSION

The relationships between distribution probability and damage occurrence should be considered in species distribution modeling for risk assessment of insect pest expansion under climate change. Our study could improve the effectiveness of risk assessment of insect pest expansion under changing climate conditions. © 2021 Society of Chemical Industry.

Measurement and spatial convergence analysis of China's agricultural green development index

Based on the comprehensive evaluation system of agricultural green development index (AGDI), this paper uses entropy weight method and linear weighted sum method to measure the agricultural green development level of 31 provinces in China from 2013 to 2018. We then incorporate spatial correlation into the traditional convergence test model, study the spatial convergence of AGDI, and explore the reasons for regional differences in AGDI. The results show that the level of AGDI in China showed an overall growth trend during the sample survey period, but there were significant differences in the rate of AGDI among different regions, mainly manifested as "eastern > western > central." The AGDI shows a significant positive spatial correlation on the whole, and its overall spatial distribution is characterized by high-high agglomeration and low-low agglomeration. The provinces with higher and lower level of AGDI still maintain the original relatively concentrated distribution in geographical space. On this basis, the study examines the regional differences of AGDI and its evolution by Dagum Gini coefficient decomposition and spatial convergence. The results showed that the overall difference of AGDI showed a fluctuating downward trend. The intra-regional difference of AGDI in the western region was the largest, and that in the eastern region was the smallest. The contribution rate of intensity of transvariation among regions was the main source of the relative difference of AGDI. Meanwhile, the AGDI of the overall, eastern, central, and western regions present significant σ convergence and conditional β convergence. Except for the central region, the overall, eastern, and western regions present significant absolute β convergence. The low-level areas of AGDI have significant "catch-up effect" on the areas with high-level AGDI. Based on the above results, this paper also puts forward some policy suggestions from the perspective of cross-regional collaborative governance to improve China's agricultural green development mode and narrow the regional differences of China's agricultural green development.

Soil heavy metal pollution and food safety in China: Effects, sources and removing technology

Soil plays a fundamental role in food safety and the adverse effects of contaminants like heavy metal (loid)s on crop quality have threatened human health. Therefore, it is important to focus on the food safety and agricultural soil pollution by heavy metals, especially for China where the demand for food production is increasing. This review comprehensively introduced the current status of agricultural soil pollution by heavy metals in China, analyzed the main sources of contaminants, including the applications of pesticides and fertilizers, atmospheric deposition related to vehicle emissions and coal combustion, sewage irrigation and mining. Food safety and agricultural soil pollution by heavy metals, the removal technologies for soil remediation such as soil amendments, phytoremediation and foliar sprays were also introduced. The review can provide significant insights for policymakers, environmental engineers, and agro-technicians regarding soil contamination control and management strategies and technologies.

China’s Land Cover Fraction Change during 2001–2015 Based on Remote Sensed Data Fusion between MCD12 and CCI-LC

New types of remote sensed land cover datasets provide key evidence for understanding global environmental change. However, low data consistency makes understanding the changes unclear. China has become a hot spot of land cover change in the world due to climate change and a series of human measures, such as ecological engineering, land consolidation, and urbanization. However, due to the inconsistencies in interpretation of signs and thresholds, the understanding of yearly-continued land cover changes in China is still unclear. We aim to produce China’s land cover fraction dataset from 2001 to 2015 by weighted consistency analysis. We compare the Moderate-resolution Imaging Spectroradiometer land cover dataset (MCD12Q1), the Climate Change Initiative Land Cover (CCI-LC) datasets, and a new land cover fraction dataset named China-LCFMCD-CCI, produced with a 1 km resolution. The obvious increased forest areas only accounted for 4.6% of the total forest areas, and were mainly distributed in northeast China. Approximately 75.8% of the grassland and shrubland areas decreased in size, and these areas were relatively concentrated in northeast and south China. The obvious increased areas of cropland (3.7%) were equal to the obvious decreased areas (3.6%), and the increased cropland areas were in northwest China. The change in bare land was not obvious, as the obvious increased areas only accounted for 0.75% of the bare land areas. The results not only prove that the data fusion of the weighted consistency method is feasible to form a land cover fraction dataset, but also helps to fully reveal the trends in land cover fraction change in China.

Cultivated Land Change, Driving Forces and Its Impact on Landscape Pattern Changes in the Dongting Lake Basin

Comprehending the dynamic change characteristics of land use/cover and the driving factors causing the change are prerequisites for protecting land resources. This paper analyzes changes in cultivated land, the driving factors that cause them, and their tremendous impact on landscape pattern changes in the Dongting Lake Basin. For this purpose, we used mathematical statistics, buffer analysis, trend analysis, landscape pattern index, and logistic regression model to analyze the land use data of the study area from 1980 to 2018. The results show that the cultivated land showed a decreasing trend, with the total area decreased by 4.76% (or 716.13 km²) from 1980 to 2018, and the activity of mutual transformation with other land use types decreased. The spatial distribution pattern of cultivated land and landscape shows the change characteristics gradually from Dongting Lake to the surroundings. Among the driving factors of cultivated land changes, the influence of human activities was gradually increasing, while the natural factors were decreasing. The cultivated land landscape pattern index and the overall landscape pattern index have a significant positive correlation, showing relatively consistent change trend and spatial distribution characteristics. We believe that the decrease of cultivated land area has a certain relationship with the increase of landscape fragmentation in the Dongting Lake Basin. Our research is expected to provide a reference for strengthening regional cultivated land management and rational development and utilization of regional land resources.

Food production in China requires intensified measures to be consistent with national and provincial environmental boundaries

Meeting increasing food demands in an environmentally sustainable manner is a worldwide challenge. Applying life cycle analysis to different scenarios, we show that a 47-99% reduction in phosphorus emissions, nitrogen emissions, greenhouse gas emissions, bluewater consumption and cropland use is needed for China's food production in 2030 to be within national and provincial environmental boundaries. Basic strategies like improving food production efficiency, optimizing fertilizer application, reducing food loss and waste and shifting diets are currently insufficient to keep environmental impacts within national boundaries-particularly those concerning nitrogen. However, intensifying these strategies and reallocating food production from the northern to the southern provinces could keep environmental impacts within both national and provincial boundaries. We conclude that the environmental sustainability of China's food production requires radical and coordinated action by diverse stakeholders.

Bt, Not a Threat to Propylea japonica

Given the ever-increasing commercial planting of transgenic plants across the world, an evaluation of their impacts on non-target organisms is as an important part of the risk assessment process. Propylea japonica is a dominant non-target predator and pollen feeder insect that is prevalent in Bt cotton fields, and it is thus in direct contact with Bt proteins. However, the effect of Bt proteins on P. japonica has not received much attention. In this study, the effects of Cry1Ac and/or Cry2Ab proteins on P. japonica were investigated from three aspects. First, no significant differences in the diversity of the microbiota nor change in species composition and community structure were observed among Cry protein treatments. Firmicutes are the most abundant bacterial phylum present in P. japonica, followed by Proteobacteria and Actinobacteria. The most abundant genus was Staphylococcus. Second, the expression levels of the detoxification and digestion-related genes did not change significantly in any Cry protein treatment. Third, none of the Cry proteins affected the population fitness of P. japonica. These results indicated that P. japonica was not sensitive to Bt proteins, suggesting that growing Bt cotton expressing Cry1Ac and/or Cry2Ab will pose negligible risks to P. japonica.

Fingerprint characteristics and health risks of trace metals in market fish species from a large aquaculture producer in a typical arid province in Northwestern China

Concentrations of nine metals were measured in eight common cultured fish species obtained from forty-three aquatic product markets across three cities in Xinjiang province, to establish fingerprint characteristics and assess potential human health risks due to the consumption of fish. Metal levels ( μ g/kg, wet weight) in fish muscles were: 1204.88-5113.19 Al, 2.09-12.44 V, 6.10-31.86 Cr, 2368.80-8949.52 Fe, 2.01-10.26 Co, 4082.72-12785.68 Zn, 174.89-763.83 Cu, 0.33-2.24 Cd, and 5.74-9.90 Pb. Fingerprint analysis revealed that the studied fish species from the three cities exhibited a similar pattern of distribution. From the viewpoint of human health, the assessment of non-carcinogenic risk indicated no significant adverse health effects due to consumption of the assessed fish species.

Pollution characteristics and ecological risk assessment of heavy metals in paddy fields of Fujian province, China

To analyze the concentration, spatial distribution patterns, and ecological risks of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co), 272 topsoil samples (0–20 cm) were collected from paddy fields in Fujian province in July 2017. The results revealed that the mean concentration of all heavy metals exceeded the background values in Fujian province, with the mean concentration of Cd being 5.20 times higher than its background. However, these concentrations of heavy metals were lower than their corresponding national standards (GB 15618-1995). Spatially, for Cd, the high concentration areas were located mainly in southeast of Sanming city and northeast of Quanzhou city. For Pb and As, the places of highest concentration were mainly in southeast of Quanzhou city and Zhangzhou city, and the main areas of high Ni concentration were distributed southeast of Nanping city. The geo-accumulation index (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${I}_{geo}$$\end{document}Igeo) of Cd and As were indicative of moderate contaminations, and the index of Co, Cu and Cr suggested that these were practically uncontaminated. The nemerow integrated pollution index (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${P}_{n}$$\end{document}Pn) showed that the entire study area was prone to a low level of pollution, but at the county level, Yongcun county and Zhaoan county are in an warning line area of pollution. According to the potential ecological risk (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$RI$$\end{document}RI), the ecological risk belongs to the low risk of paddy fields in Fujian province. However, Cd should be given attention (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${E}_{r}$$\end{document}Er = 25.09), as it contributed to the majority of potential ecological risks in Fujian province.

A dynamic model to evaluate the critical loads of heavy metals in agricultural soil

Estimation of critical load (CL) is important for soil environmental management and pollution prevention. We developed a mass balance-based dynamic critical load (DCL) model, which improved the model performance, applicability and functionality compared with the traditional one. Paddy soils in two typical fields in central south China and two scenarios were chosen as case studies. The result of case study showed that atmospheric deposition was the main source of Cd, Cu, Pb, and Zn in the soils, with percentage contributions ranging from 59.9 to 79.8%. Crop uptake, particularly the rice straw harvest, was the primary output pathway, accounting for 35.1-71.2% of the total output flux. The critical loads also known as annual input limits (I_max) of heavy metals in the paddy soils were calculated by the developed DCL model. For example, the Imax of Cd was recommended as 0.05 kg ha^-1 in the paddy soils under the default scenario for a protection period of 40 years, and that became 0.12 kg ha^-1 and 0.17 kg ha^-1 under the straw removal scenario in the two typical fields, respectively. The scenario simulation suggested that the straw removal strategy reduced the total concentrations of heavy metals (C_t) in the soils and notably increased the I_max. Meanwhile, the sensitivity analysis indicated that the changes of C_t and I_max can be controlled by adjusting the partition coefficient (K_d), plant uptake factor (PUF) and input flux. The mass balance-based DCL model provides a reference method to establish the standard for controlling heavy metal inputs to agricultural soil, this will be helpful to develop strategies for the prevention of soil contamination.

Spatially-explicit modeling and intensity analysis of China's land use change 2000-2050

Land use change affected by wide ranges of human activities is a key driver of global climate change. In the last three decades, China has experienced unprecedented land use change accompanied by increasing environmental problems. There is a pressing need to project and analyze long-term land use scenarios that are critical for land use planning and policymaking. Using GlobeLand30 data, we examined China's land use change from 2000 to 2010, and developed a novel LandCA model for scenario projections from 2020 to 2050. The observed and projected land use change (2000-2050) was analyzed in terms of the interval, category, and transition levels. Our findings show that land Exchange intensity is more than 3 times greater than land Quantity intensity from 2000 to 2050, and the overall rate of land use change will decelerate from 2010 to 2050. During 2000-2010, the loss of built-up land to other categories was 12.7% while the gain was 32.5%, with a growth rate 3.4 times larger than that during 2010-2050. The total amount of cultivated land continuously decreases but will not violate the Chinese "Cultivated Land Red-Line Restriction" by 2050. We speculate that the government's goal of 26% forest cover by 2050 may not be achieved, as a result of strict land use policies preventing the transformation from cultivated land to forests. This study contributes to new evaluations of long-term land use change in China for the government to adjust policies and regulations for sustainable development.

Large increases of paddy rice area, gross primary production, and grain production in Northeast China during 2000-2017

China is the largest rice producer and consumer in the world. Accurate estimations of paddy rice planting area and rice grain production is important for feeding the increasing population in China. However, Southern China had substantial losses in paddy rice area over the last three decades in those regions where paddy rice has traditionally been produced. Several studies have shown increased paddy rice area in Northeast China. Here we document the annual dynamics of paddy rice area, gross primary production (GPP), and grain production in Northeast China (Heilongjiang, Jilin and Liaoning provinces) during 2000-2017 using agricultural statistical data, satellite images, and model simulations. Annual maps derived from satellite images show that paddy rice area in Northeast China has increased by 3.68 million ha from 2000 to 2017, which is more than the total combined paddy rice area of North Korea, South Korea, and Japan. Approximately 82% of paddy rice pixels had an increase in annual GPP during 2000-2017. The expansion of paddy rice area slowed down substantially since 2015. Annual GPP from those paddy rice fields cultivated continuously over the 18 years were moderately higher than that from other paddy rice fields, which suggested that improved management practices could increase grain production in the region. There was a strong linear relationship between annual GPP and annual rice grain production in Northeast China by province and year, which illustrates the potential of using satellite-based data-driven model to track and assess grain production of paddy rice in the region. Northeast China is clearly an emerging rice production base and plays an increasing role in crop production and food security in China. However, many challenges for the further expansion and sustainable cultivation of paddy rice in Northeast China remain.

Genome-wide associated study identifies NAC42-activated nitrate transporter conferring high nitrogen use efficiency in rice

Over-application of nitrogen fertilizer in fields has had a negative impact on both environment and human health. Domesticated rice varieties with high nitrogen use efficiency (NUE) reduce fertilizer for sustainable agriculture. Here, we perform genome-wide association analysis of a diverse rice population displaying extreme nitrogen-related phenotypes over three successive years in the field, and identify an elite haplotype of nitrate transporter OsNPF6.1^HapB that enhances nitrate uptake and confers high NUE by increasing yield under low nitrogen supply. OsNPF6.1^HapB differs in both the protein and promoter element with natural variations, which are differentially trans-activated by OsNAC42, a NUE-related transcription factor. The rare natural allele OsNPF6.1^HapB, derived from variation in wild rice and selected for enhancing both NUE and yield, has been lost in 90.3% of rice varieties due to the increased application of fertilizer. Our discovery highlights this NAC42-NPF6.1 signaling cascade as a strategy for high NUE and yield breeding in rice.

Improving crop nitrogen use efficiency can facilitate sustainable production, however, the genetic mechanisms have not been fully revealed. Here, the authors discover the NAC42-NPF6.1 signaling cascade mainly derives from indica and wild rice and demonstrate the potential of using the allele for cultivar improvement.

Decomposition of factors affecting changes in non-CO2 greenhouse gas emission intensity of China's livestock sector based on the concept of "environment-food-economy"

The livestock sector is the main source of non-CO₂ greenhouse gas (GHG) emissions in China. Decomposing the factors that influence non-CO₂ GHG intensity in the livestock sector (LGI) serves as an important reference for the development of specific emission reduction policies. However, the difficulty lies in how to consider the relationship between emission reductions and the human food supply and economic development. In this study, a decomposition framework for the LGI in China was constructed from the concept of "environment-food-economy." The influencing factors that drove changes in LGI were interpreted at the environmental level, economic level, and scale level. Additionally, the logarithmic mean Divisia index (LMDI) method was used to quantify the contributions of these three drivers in 31 provinces across China from 1998 to 2016. The results showed that: (1) the LGI of China decreased by 80.02% during the study period. This decrease was mainly driven by the environmental and economic level factors of each province with a respective cumulative contribution of 51.96% and 34.10%. However, the scale-level factor of each province cumulatively suppressed the LGI drop by 6.04% in China. (2) For the contribution of the environmental-level factor, the top five provinces were Henan, Yunnan, Inner Mongolia, Guangxi, and Shandong. The top five provinces for the economic-level factor contribution were Henan, Sichuan, Shandong, Hebei, and Heilongjiang. (3) Under the concept of the livestock sector "environment-food-economy", improving the environmental and economic levels of the livestock sector in each province, and narrowing its inter-provincial gaps are two feasible ways that can be used to reduce China's LGI. Our research methodology is applicable to studies on the reduction of LGI in regions of different scales.

Bioaccumulation of potentially toxic elements by submerged plants and biofilms: A critical review

The accumulation of potentially toxic elements (PTEs) in aquatic ecosystems has become a global concern, as PTEs may exert a wide range of toxicological impacts on aquatic organisms. Submerged plants and the microorganisms attached to their surfaces, however, have displayed great potential as a means of coping with such pollution. Therefore, it is crucial to understand the transport pathways of PTEs across sediment and organisms as well as their accumulation mechanisms in the presence of submerged plants and their biofilms. The majority of previous studies have demonstrated that submerged plants and their biofilms are indicators of PTE pollution in the aquatic environment, yet relatively little is known about PTE accumulation in epiphytic biofilms. In this review, we describe the transport pathways of PTEs in the aquatic environment in order to offer remarkable insights into bioaccumulation mechanisms in submerged plants and their biofilms. Based on the literature cited in this review, the roles of epiphytic biofilms in bioaccumulation and as an indicator of ecosystem health are discussed.