Grain-producing Areas In China Research Articles

Spatiotemporal Variation Characteristics and Driving Factors of Cultivated Land NPP in the Shandong Area Around the Bohai Sea

The Bohai Rim Plain is an important grain-producing area in China. The cultivated land resources have great potential for production, but there are many influencing factors. Understanding the spatiotemporal change characteristics and driving factors of the net primary productivity （NPP） of cultivated land vegetation in this region is of great significance to improve the regional cultivated land production conditions, excavate and enhance the production capacity of cultivated land, and ensure national food security. In this study, Theil-Sen Median trend analysis, Mann-Kendall significance test, Hurst index, and other methods were used to explore the spatiotemporal change characteristics, stability, and sustainability of regional cultivated land NPP. The influence of driving factors on the spatial heterogeneity of cultivated land NPP was analyzed by using optical parameters-based geographical detectors. The results showed that： ① From 2001 to 2019, due to the expansion of construction land during industrialization and urbanization, the cumulative decrease in the area of cultivated land in the Shandong area around the Bohai Sea was 2 004.51 km2. ② During the selected research period, the interannual variation of average cultivated land NPP showed a fluctuating and increasing trend. In terms of spatial distribution, the NPP of cultivated land was bounded by the Dongying District, with the spatial heterogeneity in the north being significantly lower than that in the south. ③ The area with increasing NPP of cultivated land accounted for 88.06% of the total area of cultivated land, mainly with low and medium fluctuations. The NPP of cultivated land will maintain an overall sustained trend of increase across the region in the future. ④ The average annual relative humidity study area had the strongest explanatory power for the spatial variability of NPP in cropland, with a q-value of 0.26, followed by surface soil salinity and subsoil salinity, with q-values greater than 0.2. The interactions between the different drivers all showed either nonlinear enhancement or bifactorial enhancement. The results of this study will help to reveal the characteristics of the changes in cultivated land production capacity and its driving forces in the Bohai Sea region and also provide a theoretical basis for the ecological protection and sustainable development of the region.

Integrating Risk-Conflict assessment for constructing and optimizing ecological security patterns of Polder landscape in the Urban-Rural fringe

Jianghan Plain is an important grain-producing area in China, and the transformation of the natural environment by the long-term polder activities of the people in this area has created a characteristic polder landscape. After 2000, urbanization has led to the destruction of ecosystems in these polder landscapes, especially in sensitive areas at the urban–rural interface. ESP can help mitigate this threat by systematically identifying and connecting ecologically significant areas to enhance ecosystem stability and sustainability. In this paper, taking Dongxihu Polder as an example, we apply multi-source remote sensing data to develop LER and LUC models. Combining these with MCR model, we construct an ESP for Dongxihu Polder. The study shows that (1) the growth of LER and LUC in Dongxihu Polder is characterized by “strong dynamics, high complexity and weak protection”, which is closely related to the urban expansion of the urban–rural boundary area; (2) Watersheds, woodlands, and farmlands play an important role in controlling LERs and LUCs, so we identified 33 ecologically important source areas that are mainly concentrated in these regions; (3) In this paper, 46 ecological strategic nodes and 16 ecological corridors were extracted to construct the Dongxihu Polder ESP of “one ring, five axes, multiple points and multiple chains”, and suggested specific optimization strategies. The study provides feasible ecological management policy recommendations for the protection as well as sustainable development of Dongxihu Polder.

The adaptability and irrigation constraints analysis of the WOFOST model for grain production in the Songhua River Basin.

The Songhua River Basin, a vital grain-producing area in China, faces challenges due to the uneven distribution of water resources and the intensive water demands of agriculture. To enhance agricultural development and effectively manage water scarcity, it is essential to identify the water-saving potential of major staple crops - corn, wheat, and rice. This study enhances the World Food Studies (WOFOST) model by refining the day of year for the developmental vegetative stage (DVS), thereby improving the representation of phenological stages for spring maize, spring wheat, and rice within the model. This refinement offers a detailed analysis of the potential and rainfed yields. The results from the modified WOFOST model show promising simulation outcomes for the biomass and yield of maize, wheat, and rice, with Nash-Sutcliffe efficiency (NS) and index of agreement (IoA) values all exceeding 0.7. An analysis of photothermal potential yields (Yp) and rainfed yields (Yr) revealed minimal differences in yields for spring maize and rice across various rainfall frequencies. Specifically, the average photothermal utilization rates (LTs) are 93.57% for maize and 85.25% for rice. In contrast, the rainfed yield for wheat is lower than its photothermal yield, with an LT of 43.66%. These findings suggest that in the Songhua River Basin, maize and rice offer greater potential for water conservation compared to wheat. It is recommended to judiciously reduce irrigation during the growing seasons of spring maize and rice to help alleviate agricultural water use pressures. © 2024 Society of Chemical Industry.

Coupling and Coordination Analysis of Digital Economy and Green Agricultural Development: Evidence from Major Grain Producing Areas in China

Analyzing the coupled coordination of the digital economy (DE) and agricultural green development (AGD) and exploring the main influencing factors affecting their coupled coordination are key to achieving high-quality and sustainable development in agriculture. These measures are also crucial for achieving the United Nations’ Sustainable Development Goals (SDGs). In this study, we constructed a comprehensive evaluation system including two subsystems, DE and AGD, and firstly measured the development of DE and AGD and their trends in 13 provinces in China’s main grain-producing areas during the decade from 2012 to 2021 using EW-TOPSIS. Secondly, the coupling coordination development (CCD) model was used to analyze the static results and dynamic evolution process of CCD of the DE and AGD subsystems in the study area. Finally, the gray correlation degree (GCD) model was used to identify the main influencing factors in the interaction between the two systems in 2012 and 2021. The results show the following: (1) The development levels of DE and AGD generally rose during the study period, but the development level gap between regions was obvious, and the development of DE relatively lagged behind. (2) The level of CCD increased year by year, and the overall process changed from “uncoordinated” to “coordinated”. (3) At the beginning of the study period, the development achievements of DE had a great impact on the process of AGD. The application of advanced agricultural technology in the AGD system and the process of agricultural industry upgrading had a profound impact on the development of DE. However, a decade later, the main factors had changed. This paper analyzes the results of the above empirical study in time and space, aiming to provide policymakers with new working ideas to achieve the SDGs.

Construction of Cultivated Land Ecological Network Based on Supply and Demand of Ecosystem Services and MCR Model: A Case Study of Shandong Province, China

The research on the ecological protection of cultivated land has gradually become a focus and frontier of cultivated land protection. Constructing an ecological network of a cultivated land system is important to improve the effect of cultivated land ecological protection. In this study, the supply-demand ratio of five ecosystem services was calculated from 2000 to 2020 in Shandong Province, a major grain-producing area in China. The morphological spatial pattern analysis (MSPA) model was used to construct the minimum cumulative resistance (MCR) model. The conclusions of the study are as follows: (1) the areas with a higher supply and demand ratio of various ecosystem services of cultivated land in Shandong Province are distributed in southern and southwestern areas. (2) The ecological source of cultivated land in Shandong Province has decreased by about 7000 km2 from 2000 to 2020, and the fragmentation trend is obvious. (3) The total length of the ecological corridors is 798.5 km2. The majority of these corridors are located in central and southern Shandong. The ideas and conclusions of this study are important for the formulation of ecological protection policies for regional cultivated land systems.

Spatiotemporal Changes and the Prediction of Drought Characteristics in a Major Grain-Producing Area of China

Understanding variations in drought characteristics is of great importance for water resource planning and agriculture risk management. Despite increasing interest in exploring spatiotemporal drought patterns, long-term drought event characteristics and their future changes are unclear in major grain-producing areas in China. In this study, we applied Run theory, Sen’s slope, the modified Mann–Kendall method, wavelet analysis, and three machine learning models to systematically examine drought variation patterns, their future trends, and agricultural exposure in Henan Province, China, from 1961 to 2019. The results indicated that the SPEI-12 showed a significant increase at a rate of 0.0017/month during 1961–1999, but this has gradually changed to a drying trend since the 21st century. Drought event characteristics shifted markedly during these two periods, with drought duration and severity gradually shifting from east to west. The BO-LSTM model performed better than the LSTM and BP models, indicating that the drought frequency, higher drought duration, and drought peak would greatly increase 1.28–3.40-fold and cropland exposure is predicted to increase 1.61-fold in the near future compared to the first two decades of the 21st century. This finding not only helps developing meteorological drought predicting models, but also provides the scientific groundwork for drought disaster prevention and mitigation in Henan Province.

Incorporating carbon sequestration toward a water-energy-food-carbon planning with uncertainties

Water-energy-food nexus (WEFN) is the core content in the United Nations 2030 Agenda for Sustainable Development. However, the value of soil and crops' carbon sink function has not yet been fully considered in the managment practices of WEFN system. Here, we developed a water-energy-food-carbon nexus (WEFCN) planning framework that incorporates carbon sequestration and multiple mathematical optimization methods into the practical WEFN management for Henan Province, which is one of major grain-producing areas in China. Uncertainties from multiple objectives, scenarios, and different stakeholder interests are captured. We found that wheat has the largest carbon sequestration, followed by corn and oil-bearing crops, while other crops have implicit carbon sequestration. Since chemical fertilizer produces the most carbon emissions, the usage of chemical fertilizer needs to be reasonably controlled. Overall, the proposed framework supports optimal decision-making for regional-scale WEFCN management and further unlocks the hidden value of agricultural carbon mitigation.

Comparative Analysis of the Evolutionary Characteristics and Influencing Factors of Land and Water Resource Systems in Major Grain-Producing Areas

In the process of rapid advancement of agricultural production, the dynamic evolution characteristics of land and water resources in the main grain-producing areas and the influencing factors are less studied. This study takes Heilongjiang Province, the main grain-producing area in China, as an example, constructs an index system from three functions: production, life, and ecology, uses information entropy to determine the weights and importance of each index, uses the rate of change of the index to determine the basic data of the dynamic development of the system, combines the weights to determine the dynamic evolution characteristics, and compares and analyzes them with the static evolution characteristics determined by the actual data. The results showed that there were differences in the important indicators under different conditions, and the important indicators under static and dynamic conditions were the proportion of the tertiary industry to GDP(A7) and GDP per unit area(A8), with importance weights of 7.45% and 8.0%, respectively. The static evolution index of the land and water resource system increased slowly from 0.16 to 0.91, while the dynamic evolution index fluctuated and declined from 0.58 to 0.34, indicating that the ability of the land and water resource system in the study area to maximize comprehensive benefits is constantly weakening. Managers can pre-control the development speed of the important indicators under dynamic conditions and promote the sustainable development of the land and water resource system.

Estimation of the Total Soil Nitrogen Based on a Differential Evolution Algorithm from ZY1-02D Hyperspectral Satellite Imagery

Precise fertilizer application in agriculture requires accurate and dependable measurements of the soil total nitrogen (TN) concentration. Henan Province is one of the most important grain-producing areas in China. In order to promote the development of precision agriculture in Henan Province, this study took the high-standard basic farmland construction area in central Henan Province as the research area. Using single-phase images acquired from the ZY1-02D satellite hyperspectral sensor on 28 January 2021 (with a spatial resolution of 30 m × 30 m, a spectral range that covered 400–2500 nm, and a revisit period of 3 days) for spectral reflectance transformation and feature spectral band extraction. Based on multiple representation models, such as multiple linear regression, partial least squares regression, and support vector machine (SVM), all bands, feature bands, feature band combinations, and differential evolution (DE) algorithms were used to extract the secondary characteristic variables of the combination of characteristic bands, which were used as model inputs to estimate the content of TN in the study area. It was found that (1) the spectral reflectance transformation could help to improve the accuracy of prediction by reducing the interference from noise in the model, but the optimal spectral transformation method differed between different models and even between the training and test sets of the same model; (2) the estimation accuracy of the TN content model based on the minimum shrinkage and feature selection operator of the feature band was usually better than that of the full band, the feature combination band contained more effective information related to the TN content, and the combination of the DE algorithm and the SVM model achieved a better estimation accuracy for secondary feature extraction and TN content estimation of the feature combination band; and (3) ZY1-02D hyperspectral satellite data have the potential for the dynamic and non-destructive monitoring of regional TN content.

Quantitative Assessment of Horizontal Ecological Compensation for Cultivated Land Based on an Improved Ecological Footprint Model: A Case Study of Jiangxi Province, China.

Cultivated land horizontal ecological compensation is an essential means of reconciling agricultural ecosystem protection and regional economic development. It is important to design a horizontal ecological compensation standard for cultivated land. Unfortunately, there are some defects in the existing quantitative assessments of horizontal cultivated land ecological compensation. In order to raise the accuracy of ecological compensation amounts, this study established an improved ecological footprint model based on the ecosystem service function, focused on estimating the value of ecosystem service function, ecological footprint, ecological carrying capacity, ecological balance index and ecological compensation values of cultivated land in all cities of Jiangxi province. It then analyzed the rationality of ecological compensation amounts in Jiangxi province, which is one of the 13 provinces of major grain-producing areas in China. The results show the following: (1) The total value of soil conservation service function, carbon sequestration and oxygen release service function and ecosystem service function in Jiangxi province showed a spatial distribution trend of "gradually increasing around Poyang Lake Basin". (2) The cultivated land ecological deficit areas in Jiangxi province are Nanchang City, Jiujiang City and Pingxiang City; ecological surplus areas are Yichun City, Ji'an City and eight other cities; and there is an obvious "Spatial Agglomeration" phenomenon in ecological deficit and ecological surplus areas where ecological deficit areas are mainly concentrated in the northwest region of Jiangxi. (3) The amount needed to attain fair ecological compensation for cultivated land is 5.2 times the payment amount for cultivated land; this indicated there is larger arable land, a favorable condition for agricultural cultivation, and better supply capacity of ecosystem services in most of the cities of Jiangxi. (4) The compensation amount for cultivated land ecological surplus areas in Jiangxi province is generally higher than the cost of ecological protection, and its proportion in GDP, fiscal revenue and agriculture-related expenditure is significantly higher than that in ecological deficit areas; this indicated that the compensation value of cultivated land could play the driving role in the protective behavior for cultivated land. The results provide a theoretical and methodological reference for the construction of horizontal ecological compensation standards for cultivated land.

Coupling coordination analysis and spatiotemporal heterogeneity of the agricultural eco-economic system in the main grain-producing areas of Jilin Province.

Jilin is a major agricultural province and an important grain-producing area in China. Under the requirements of ensuring national grain security and green development for regional agriculture, the coordinated development of agricultural ecology and the economy in grain-producing areas is a crucial issue. Sixteen major grain-producing counties in Jilin Province were selected and a comprehensive evaluation index of the agricultural eco-economic system was established to analyze the relationship between the two subsystems in the main grain-producing areas from 2004 to 2018. The study aimed to determine the relationship between agricultural ecology and the economy in the grain-producing areas of Jilin and how to promote high-quality development of the agricultural system according to the local conditions. The results showed that (1) the coupling coordination degree (CCD) in the main grain-producing areas was steadily improved during the study period and was closely related to the impact of agricultural policies; (2) the CCD of the central area was less than that of the west, mainly because the agricultural ecological development lagged far behind the economy; (3) agricultural modernization, environmental protection, and increasing grain added value were important ways to promote CCD development in the grain-producing areas. This study emphasized the importance of the coordinated development of agricultural ecology and the economy and provides an important reference for formulating regionally differentiated development strategies and achieving sustainable agriculture in main grain-producing areas.

Determining urban‒rural coordinated development in major grain-producing areas based on urbanization and cultivated land use efficiency coordination level: A case study in Hunan Province, China

Urbanization and cultivated land use coordination is the key to urban‒rural coordinated development, especially in the major grain-producing areas in China, but it is rarely examined. A coordination framework of urbanization and cultivated land use efficiency systematically clarified how to achieve Urbanization and cultivated land use coordination. Taking Hunan Province as an example, this study explored the spatiotemporal evolution of the level of Urbanization and cultivated land use coordination from 2000 to 2018 at the county level, identified current types of Urbanization and cultivated land use coordination and discussed the key optimization measures for different types. The results showed that 1) urban‒rural coordinated development, abstractly represented by the Urbanization and cultivated land use coordination in major grain-producing areas, depends on the intensity of interactions and the level of integration of urbanization and cultivated land use systems. 2) From 2000 to 2018, the level of Urbanization and cultivated land use coordination in Hunan changed from serious maladjustment to great maladjustment to coordination. 3) The current Urbanization and cultivated land use coordination pattern in Hunan Province has a strong spatial differentiation, which can be divided into eight subregions. The key to the coordinated development of each type is to accelerate the flow of elements through deepening reform and innovation mechanisms to complement the shortcomings of development. This study will provide a scientific reference for the effective implementation of regional coordinated development strategies in major food-producing regions.

A Study on Spatial-Temporal Differentiation and Influencing Factors of Agricultural Water Footprint in the Main Grain-Producing Areas in China

It is an urgent scientific issue to explore the spatial and temporal differentiation and impact indicators of the agricultural water footprint in major grain-producing areas. Therefore, this study tries to use the water footprint theory to implement top-down calculation of the agricultural water footprint in major grain-producing regions from 2000 to 2019 and investigate the various impacts on the agricultural water footprint under the influence of spatial-temporal effects using spatial autocorrelation and the spatial Dubin model. The results indicate that from 2000 to 2019, the overall agricultural water footprint of China showed a fluctuating downward trend in an inverted N shape and demonstrated high–high and low–low spatial aggregation characteristics. There are notable characteristics, including high spatial dependence, spatial barriers, and path locking of the agricultural water footprint in most provinces and regions of the main grain-producing areas. Policy factors, water-saving technologies, social development, economic development, and industrial structure adjustment are all significantly and negatively correlated with the increase in the agricultural water footprint, while agricultural production and natural factors have a significant positive relationship with the agricultural water footprint. The spatial spillover effect of water-saving technologies, industrial restructuring, agricultural production, and natural factors is powerful. Therefore, a rationally optimized industrial structure, strengthened regional linkage of water resources management and control, and the promotion of efficient water infrastructure technology are important ways to inhibit the agricultural water footprint.

Distribution Characteristics and Formation Mechanisms of Highly Mineralized Groundwater in the Hetao Plain, Inner Mongolia

As the largest artesian irrigation area in northern China, the Hetao Plain is also one of the major grain-producing areas in China. Meanwhile, there is a large amount of highly mineralized groundwater resulting in the soil salinization and desertification in this region. In addition, this study also uses the traditional hydro-geochemical methods to investigate the spatial evolution characteristics and formation mechanisms of highly mineralized groundwater. The results indicate that there is a large amount of highly mineralized groundwater (salinity > 3 g/L) in the shallow aquifer over the Hetao Plain. As far as the spatial patterns are concerned, there are significant spatial differences. In accordance with the structural, paleogeographic, landform, and hydrogeological conditions, the highly mineralized groundwater in the Hetao Plain can be divided into five zones, namely, the front fan depression, the north bank of the Yellow River, Xishanzui, Hasuhai in the Hubao Plain, and Dalad banner on the south bank of the Yellow River. Among them, the highly mineralized groundwater of Xishanzui exhibits the largest value of the salinity > 10 g/L. The main cations are Mg2+ and Na+, while the main anions are Cl− and SO42−. Moreover, the groundwater in the highly mineralized area contains a large amount of I−. According to the analysis of Piper, Gibbs diagrams of groundwater, the proportion coefficients of various components and the indication of isotope, it can be seen that most of the chemical ions in groundwater in the highly mineralized zone come from evaporation-concentration, which are mainly affected by climate, sedimentary environment, hydrogeological conditions and hydrology. The source of high mineralization in Xishanzui are different from other high mineralization regions, and the highly mineralized groundwater in Xishanzui is formed by the infestation of deep underground salt brine. These results can provide scientific basis for the rational allocation of regional water resources and the promotion of water resources development and utilization.

Value conflicts in grassroots environmental management from a network perspective: a case study of crop residue management in Harbin, China.

Open burning of crop residue is a hot issue in Asia and has attracted widespread attention. However, this attention rarely extends to the complex interactions between multi-stakeholders in the governance process, which is precisely the focus of today's environmental governance dilemma. Harbin is a major grain-producing area in China, the annual air pollution caused by the open burning of crop straw is more prominent than in other parts of China, and the conflicting relationships among multi-stakeholders are also typical. Taking Harbin as a case, this study quantifies the complex relationships among stakeholders through value demands conflicts and constructs a value conflict network in the context of straw governance. Through the analysis of the network nodes and relationships, we found that grassroots governments and farmers are the core of the conflict, while public and higher-level governments, as supervisory subjects, are marginalized. The multiple identities and value demands of the grassroots government, as well as cost and technology constraints, are the main reasons for the governance dilemma. In addition, the grassroots government in different scenario dimensions has different conflict resolution strategies, and it has a strong self-adaptation ability in the embedded value conflict network and can influence and reshape other stakeholders. These findings highlight the critical role of the grassroots government in crop residue governance, add to the research paradigm on grassroots environmental management from a multiple-stakeholder participation perspective, and provide a theoretical and methodological basis to formulate effective strategies.

First record of Aphelenchoides besseyi on foxtail millet (Setaria italica) in Henan Province of China.

Aphelenchoides besseyi is one of the important plant-parasitic nematodes on rice, reducing approximate 10-20% of the rice yield annually (Jones et al. 2013). Foxtail millet (Setaria italica) has been a major cereal crop in Northern China, especially in the semi-arid areas of this region, for thousands of years. In August of 2019 and 2020, a survey of nematodes on autumn grain crops was performed each year. One foxtail millet field (N34° 58' 027″ and E113° 39' 059″) in Yuanyang County of Henan Province caught our attention. Some upper leaves showed chlorosis without or with necrotic tips, and flag leaves presented crinkling and distortion, stalks were colored, earheads were vertical, glumes were brown or light black and open, and grains became thin. A total of ten samples were collected, and the nematodes were isolated from the spike pieces by shallow plate method and counted under a stereomicroscope. The average number of nematodes per earhead of foxtail millet counted up to 1738.75 ± 107.72. Morphologically, females were slender with a short stylet, an oval metacorpus with a distinct valve, a labial region slightly wider than the first body annulus and a conoid tail with a terminus bearing a star-shaped mucro with four pointed processes. The females were characterized as follows (mean ± SD; n=20): body length (L) = 668.92 ± 12.73 µm (647.38 to 689.70 µm); maximum body width (W) = 14.35 ± 1.11 µm (12.12 to 16.88 µm); L/W = 46.83 ± 2.94 (40.44 to 50.03); tail length = 38.93 ± 3.48 µm (33.41 to 45.92 µm); L/tail length = 17.31 ± 1.44 (14.47 to 19.62); and stylet length (ST) = 11.57 ± 0.57 µm (10.77 to 12.34 µm). The males had three pairs of ventrosubmedian papillae with the first one adanal, spicula curved with a slight basal process, terminus bearing four mucrones arranged variably, and the whole worm was in 'J' shape. The males could be described as follows (mean ± SD, n = 20): L = 606.66 ± 10.70 µm (586.49 to 626.37 µm); W = 13.95 ± 0.60 µm (12.71 to 14.94 µm); L/W = 43.55 ± 1.69 (40.73 to 46.43); tail length = 35.54 ± 1.93 µm (31.41 to 38.18 µm); L/tail length = 17.07 ± 0.79 (16.05 to 18.67); ST = 11.53 ± 0.56 µm (1061 to 12.76 µm). All the key morphometrics were consistent with those of A. besseyi reported from Brazil (Favoreto et al. 2018) and China (Lin et al. 2004; Ou et al. 2014). The amplifications of rDNA internal transcribed spacer (ITS) fragments generated a PCR fragment of 830 bp from a single nematode, using the primers set TW81 (5'-GTTTCCGTAGGTGAACCTGC-3') and AB28 (5'-ATATGCTTAAGTTCAGCGGGT-3') (Joyce et al. 1994). Five independent PCR experiments were conducted, and all the PCR products were purified and sequenced. Nucleotide sequence of ITS-rDNA was deposited in GenBank with Accession Number OK090549.1. The obtained ITS region sequence was more than 99% identical to those of A. besseyi reported from China (MW216945.1) and India (JF826518.1, JF826519.1 and JF826517.1). These ITS sequence results further supported that the isolated nematodes were A. besseyi. Subsequently, the species-specific primers of A. besseyi (BSF, 5'-TCGATGAAGAACGCAGTGAATT-3' and BSR, 5'-AGATCAAAAGCCAATCGAATCAT-3') were used for confirmation by PCR (Cui et al. 2010). An expected PCR fragment of 312 bp was obtained, which was consistent with those of A. besseyi reported previously. The pathogenicity of identified A. besseyi was confirmed by infection of foxtail millet (Setaria italica cv. 'Yugu33'). Foxtail millet budding seeds were sown in the pots contained 150 mL of sterile soil mixture. In two weeks, 10 seedlings were inoculated with 100 A. besseyi each, and 4 plants were non-inoculated as the control. The foxtail millet seedlings were grown in a plant-growth chamber at 25/30°C under 12 h dark/12 h light. On the average, 73.3 and 138.2 of A. besseyi were isolated from each plant at 15 and 40 days post inoculation, respectively. Both the morphological and molecular characteristics were identical with those nematodes obtained from the original samples. All the upper leaves of the inoculated plants showed chlorosis and necrosis, symptoms that were similar to those observed in the field, and neither symptom developed on the non-inoculated control plants, nor were nematodes re-isolated from the control plants. To the best of our knowledge, this is the first record of A. besseyi on foxtail millet in Henan Province of North China. Henan is one of the most important grain-producing areas in China, and A. besseyi is an important domestic quarantine nematode, which may become a severe threat to cereal production in Henan Province. Our findings will be very beneficial for A. besseyi management and further research on foxtail millet in Henan Province of North China.

Analysis on the Current Situation and Countermeasures of Food Supply Protection in Sichuan Province—Based on the “Post-Epidemic Era” Perspective

Food security means national security. Grain bears on the national economy and people's livelihood, and high-quality grain supply is the cornerstone of ensuring and maintaining social stability and development. Sichuan province is one of the 13 main grain-producing areas in China and the only one in western China. It is a major province with large population and grain consumption. Since the outbreak, the central and local governments have attached great importance to grain supply in Sichuan, and a stable grain supply system has been established in Sichuan. But at present, there are still challenges such as the decrease of sown area, shortcomings in warehousing and logistics, and prominent structural shortage of grain reserves. In view of this, suggestions are put forward to consolidate the basis of grain production, improve the system of grain purchase and storage, and strengthen market monitoring and early warning.

Towards a Sustainable Grain Production Network: An Empirical Study from Northeast China

As an important grain-producing area in China, research on the spatial correlation network of grain production in Northeast China is of great significance to ensure food security and realize the sustainable development of grain production. Based on the data of 40 cities in Northeast China from 1999 to 2019, we used the modified gravity model and social network analysis method to explore the structural characteristics of the spatial correlation network of grain production. Then, we divided the network into four blocks—net spillover block, main beneficial block, broker block, and bidirectional spillover block—and explored the interactive relationships and spillover effects between blocks. On this basis, corresponding policy recommendations were put forward. The results are as follows. (1) The spatial correlation network of grain production in Northeast China presents a complicated development trend, but the overall tightness of the network still needs to be improved. (2) The spatial correlation network of grain production is characterized by multi-center distribution, in which important nodes not only play the role of central actors but also act as intermediaries and bridges in the network. (3) There are obvious spatial correlations and spillover effects between blocks, and it is in the agglomeration stage of the agglomeration–diffusion effect.

An Analysis of the Spatiotemporal Characteristics and Diversity of Grain Production Resource Utilization Efficiency under the Constraint of Carbon Emissions: Evidence from Major Grain-Producing Areas in China.

As the most important driving force for ensuring the effective supply of grain in the country, the production stability of the major grain-producing areas directly concerns the national security of China. In this paper, considering the “water–soil–energy–carbon” correlation, water, soil and energy resource factors, and carbon emission constraints were included in an index system, and the global common frontier boundary three-stage super-efficient EBM–GML model was used to measure the grain production resource utilization efficiency of the major grain-producing areas in China from 2000 to 2019. This paper also analyzed the static and dynamic spatiotemporal characteristics and the restrictions of utilization efficiency. The results showed that, under the measurement of the traditional data envelopment analysis model, the grain production resource utilization efficiency in the major producing areas is relatively high, but there is still room to improve by more than 20%, and grain production still has enormous growth potential. After excluding external environmental and random factors, it was found that the utilization efficiency of grain production resources in the major producing areas decreased, and the efficiency and ranking of provinces changed significantly. External factors inhibit pure technical efficiency and expand the scale efficiency. The utilization efficiency of Northeast China was much higher than that of the Huang-Huai-Hai region and the middle and upper reaches of the Yangtze River region, and its grain production resource allocation management had obvious advantages. The total factor productivity index of food production resources showed an upward trend as a whole, and its change was affected by both technological efficiency and technological progress, of which technological progress had the greater impact. Therefore, reducing the differences in the external environment of different regions while making adjustments in accordance with their own potential is an effective way to further improve the utilization efficiency of food production resources.

Temporal and spatial evolution of drought in Haihe River Basin from 1960 to 2020

The Haihe River Basin is an important grain-producing area in China. It is of great significance to explore and grasp the temporal and spatial evolution of drought for drought prevention and disaster mitigation, water security, and food security. In this study, based on the standardized precipitation evapotranspiration index (SPEI), gravity center model, standard deviation ellipse, and other methods, we analyzed the temporal and spatial evolution of drought in Haihe River Basin from 1960 to 2020. The results showed that during 1960 ∼ 2020, the frequency of drought in the Haihe River Basin had an upward trend, and light drought and moderate drought occurred frequently. Light drought was prone to occur in winter (January, February, December), and moderate drought mainly occurred in March (The first month of spring). The frequency of severe drought and extreme drought has increased significantly since 1990, and the monthly impact is spreading. The annual drought barycenters are distributed in plain areas such as Beijing, Hebei province, and showed a northeast to southwest zonal distribution in the basin, with a general trend of moving toward southwest. The monthly drought barycenters are mainly distributed in the central part of the basin around Baoding, and their migratory direction is mainly northeast and southwest.