The flat terrain in the plain areas of Beijing, China makes the land easily accessible for cultivation and farming, providing vast opportunities for agricultural development. Meanwhile, these areas ...are also crucial for urban construction and economic growth. Soil type mapping plays a key role in understanding soil characteristics and guiding land management practices. However, accurately mapping soil types in plain regions can be challenging due to their low spatial variability and diverse land use types. Although land cover changes due to phenomena such as urbanization, agricultural expansion, and conversion of natural vegetation can significantly affect soil properties and distribution patterns, their impacts on soil type mapping remain unclear. This study investigated the impacts of land cover changes in plain areas on the accuracy of soil type mapping, hoping to provide effective assistance for soil type mapping in plain areas by analyzing their coupling relationship. Focusing on the 20 year land cover changes in Tongzhou District, this study utilizes a unified approach that combines expert knowledge, mixed sampling methods, and RF mapping techniques, while incorporating environmental covariates that have minimal period influence and synergistically using NDVI and land cover data from the same year. Transition matrices are used to reveal land cover changes, confusion matrices, and their derived indicators to analyze changes in soil type mapping accuracy, and coupling analysis is conducted between soil type change areas and land cover change areas. The results show that Tongzhou District has experienced rapid development over the past 20 years, with the area of construction land nearly doubling. Additionally, 29% of arable land has been converted into construction land, resulting in an increase in the accuracy of the soil map from 58.99% to 66.91% over the 20 year period. The soil type change area during this period accounts for 16.5% of the total area, with 51.9% of the changed areas overlapping with land cover change areas. These overlapping regions are predominantly influenced by human activities. In terms of cultivated land types in the study area, the quantity of arable land has decreased by approximately 29% over 20 years, while the proportion of Sandy loam calcareous fluvo-aquic soil and Light loam calcareous fluvo-aquic soil, which constitute nearly half of the soil type, has increased. These data demonstrate the coupling relationship between land cover changes and soil type variations. It is evident that improving the extent of land use in plain areas enhances the credibility of soil type mapping. Meanwhile, human activities impact land cover, which, in turn, affects and reflects changes in the soil type.
As global industrialization and its associated anthropogenic activities rapidly increase, so too does the areal extent of human-altered soils. The soil classification framework must incorporate the ...classification schemes of these disturbed soils in order to remediate land. Soil Taxonomy (ST) and the World Reference Base for Soil Resources (WRB) are the most widely used soil classification systems in the world. In this study, 15 typical anthropogenic soil profiles with engineering and technical characteristics from China were selected for a classification study. The aim of this study was to clarify the classifications of these soil profiles in the ST, WRB, Chinese Soil Taxonomy (CST), and Geogenetic Soil Classification of China (GSCC), and make references accordingly. The results showed that the WRB can classify these soils as Technosols in the first level. ST can classify most of these soils as subgroups within the different great groups under Entisols, as well as the Human-Altered and Human-Transported Material classes within the soil family differentiae. For Chinese soil classification schemes, there is a large loophole in the CST regarding the classification of anthropogenic soils. Many anthropogenic soils cannot reflect these soils’ artificial and technical naming characteristics. For the CST, revised proposals based on the WRB and ST were proposed. Based on the artificial disturbance of soil layers, a manufactured layer was added to the diagnostic basis. The Artificalic Anthrosols suborder was added, and it can be divided into the Transporti-Artificalic Anthrosols and Alteri-Artificalic Anthrosols groups. The subgroups were defined by their levels of contamination, imperviousness, and artifact content. The “T” layer symbol was added to soil profile descriptions to reflect a specific layer about technology, such as A, E, B, and C, to reflect the main genetic horizons. This revised classification system is proposed for inclusion in the revised CST to account for the very large and expanding extent of disturbed soils in China and to remain current with other global soil taxonomy systems.
Assessing farmland suitability is a crucial step towards the rational utilization of land resources and ensuring sustainable agricultural development. Despite China's position as a major producer and ...consumer of agricultural products, a comprehensive map of farmland suitability based on crop suitability has yet to be produced. Additionally, significant changes have occurred in China's agricultural production space over the past few decades, and research on the correlation between these changes and farmland suitability is lacking, posing a serious threat to agricultural security and sustainable land use.
This study aims to investigate the spatial suitability of six crops, namely rice, wheat, maize, soybean, rape, and cotton, and to determine the corresponding range of farmland suitability. Additionally, this research aims to analyze the degree of matching between land cover and farmland suitability in both current and long-term time series to identify inappropriate land use and the potential for flexible farmland allocation.
In this study, we applied the optimized maximum entropy (MaxEnt) model to simulate the spatial distribution of crop suitability by integrating six crop occurrence records and environmental variables. The land suitability space was determined by computing the suitability results for all six crops using the maximum-value compositing algorithm.
The optimized MaxEnt model significantly enhanced the model's performance and transferability. Environmental variables influenced the proportion of suitable area for the six crops, with soybean > rape > maize > wheat > rice > cotton in descending order. In China, 64.96% of the land was suitable for cultivation, with 22.64% being highly suitable. In 2020, the farmland areas that were highly suitable, moderately suitable, poorly suitable, and unsuitable for crop cultivation accounted for 72.02%, 21.51%, 4.25%, and 2.22% of the total farmland area, respectively. The current farmland area that was highly suitable reached 135.93 million ha, which was sufficient to meet China's cultivated land preservation goal of 1.8 billion mu (120 million hectares). Of the woodland, grassland, and unused land, 28.64 million ha, 24.53 million ha, and 2.38 million ha, respectively, were found to be highly suitable for conversion into cropland. Over the past 21 years, built-up land has occupied 8.39 million ha of cropland, 86.65% of which was high-suitability cropland. In addition, 1.35 million ha of unused land were converted to farmland, with 69.80%, 17.32%, and 9.11% being highly suitable, moderately suitable, and poorly suitable for crop cultivation, respectively, while 3.77% of the converted unused land was unsuitable for planting.
The optimized MaxEnt model shows significant potential for predicting the distribution of crop suitability. Crop suitability is determined by a combination of climatic, topographic, geological, pedological, and hydrological factors. Currently, the distribution of cropland in China matches well with its suitability, and there is still sufficient suitable land available for agricultural production. However, the implementation of the "Farmland Balance Policy" has not effectively curbed the loss of high-quality farmland, and the available reserve resources for cultivation are becoming scarce.
The crop suitability spatial analysis in our study may assist farmers in adjusting their crop cultivation strategies, and the farmland suitability spatial analysis may aid managers in reconciling conflicts between farmland protection and economic development to ensure sufficient land is available for agricultural production.
•Crop suitability covering grain, oil and fiber were predicted using the optimized MaxEnt.•Crop suitability is influenced by a combination of climatic, geomorphological, geological, soil and hydrological factors.•China has abundant suitable land available for agricultural production.•China is facing the threat of highly suitable farmland being occupied and low-suitable marginal land being developed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Earthworms are important soil organisms that play critical roles in ecosystem material cycling and energy flows. Discovering and predicting the distribution of earthworm habitats is critical for ...managing biodiversity conservation projects and improving ecosystem health. However, earthworm data are challenging to obtain, and studies on the distribution of earthworms and factors affecting this have mainly been conducted in fields at a small scale; the spatial distribution of earthworms throughout China remains unclear. Species distribution models have been effectively used in macro-scale species suitability distribution studies; however, they have certain limitations. Thus, here, we optimized the maximum entropy model (MaxEnt) to achieve low complexity and high transferability, and the model was capable of predicting the potential distribution of earthworms in China. Modeling was based on the use of a developed database containing 286 earthworm occurrence records and 31 environmental variables (19 climatic, 9 soil, and 3 topographic variables). Results show that earthworm distribution is mainly controlled by the following environmental variables (with corresponding contribution rates): minimum temperature of the coldest month (18.47%), digital elevation model (17.65%), coarse fragments (16.72%), soil organic carbon (9.65%), soil type (7.53%), mean diurnal range (5.35%), and soil thickness (5.05%). The variables with the strongest influence on distribution are climate followed by landforms and soils. The relationship between the effect of environmental variables and earthworm distribution is not simple and linear, and each element has a certain threshold range. Only 50.67% of the total land area of China provides a suitable habitat for earthworms, and there are remarkable spatial differences. Of the various ecosystems, woodland ecosystems provide most of the suitable habitats, followed by cropland and grassland ecosystems, which together account for 45.74% of the land area. This study can be used as a reference for understanding and assessing ecosystem health, sustainability, and for enabling biodiversity conservation.
•Earthworm-suitable habitats were predicted using optimized MaxEnt in China.•Factors influencing earthworm distribution were ranked and thresholds were analyzed.•Climate was more critical in changing earthworm habitats than topography and soil.•Area of suitable habitat for earthworms was 50.67% of the total land area.•Woodland and cropland ecosystems provide most of the suitable habitats for earthworms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cultivated land is a crucial resource for human survival and development. The sustainable use of cultivated land is the foundation for ensuring food security and maintaining social stability. The ...Chinese government has promulgated a series of policies to protect cultivated land, focusing on the quantity, quality, and health of cultivated land. However, these policies lack adequate focus on aspects such as the intensity and sustainable use of the cultivated land. Human appropriation of net primary production (HANPP) is an important method for measuring land use intensity and ecosystem sustainability. Based on the HANPP framework, this study estimated the cultivated land use intensity (CLUI) at a 1-km-scale in Heilongjiang from 2001 to 2015. Spatial autocorrelation models were used to analyse the spatio-temporal patterns and aggregation characteristics of CLUI, and correlation analysis model was used to reveal the influencing factors of CLUI in time and space. The results included the following: (1) Utilization intensity of wheat (CLUIwheat), maize (CLUImaize), and all crops (CLUIall) increased by 0.07, 0.44, and 0.26, respectively, and rice (CLUIrice) decreased by 0.07 over 15 years. However, in the long term, cultivated land with rice had a higher utilization intensity with an average of 1.54, followed by maize (1.46) and wheat (1.23), which were significantly higher than the global average CLUI (approximately 0.84). Meanwhile, crop type conversion (from wheat and corn to rice, and from corn to rice) could significantly increase CLUI. (2) CLUIall had significant spatial heterogeneity and spatial aggregation characteristics. The barycentre of high-value aggregation of CLUIall moved to the northwest, while the barycentre of low-value aggregation moved to the southwest during the study period. (3) Fertilizers, pesticides, and plastic mulch had a significant positive correlation with CLUI. Excellent natural conditions could withstand more human disturbance and had lower utilization intensity. (4) Implementing the "Storing Grain in Land and Technology" strategy and cultivated recuperation policy to solve the high utilization intensity should be a priority. Scientific cropping structure, suitable cropping system, and reasonable fossil energy input were effective means to reduce the CLUI and achieve sustainable land use. In addition, establishing CLUI monitoring networks was an effective measure to obtain CLUI dynamics in a timely manner.
•The fluctuating increasing trend of CLUIall was found in Heilongjiang during 2001–2015.•The high-value aggregation type of CLUIall was moving to the northwest.•Cultivated land with rice had higher utilization intensity and crop type conversion could significantly change the CLUI.•CLUI varied with agricultural fossil energy inputs and natural factors.•Crop-type-specific CLUI can provide scientific support for sustainable cultivated land management and policy development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Emerging evidence has suggested the association of the gut microbiome with some human diseases, including type 2 diabetes (T2D). In this study, we analyzed the gut microbiota from a cohort of healthy ...and diabetic Chinese individuals from Northern China. Pyrosequencing of the V4V5 region of 16S rRNA genes revealed a significant decrease in the gut microbiota diversity of diabetic patients as compared to healthy individuals. Butyrate-producing bacteria such as Bifidobacterium and Akkermansia were significantly decreased in diabetic patients. Furthermore, the abundance of Dorea was significantly increased in T2D individuals and negatively correlated with the abundance of butyrate-producing bacteria. The increase of Dorea could play a role in the development of T2D and has been previously overlooked. Importantly, functional analysis of the gut microbiome revealed for the first time that increased levels of butyrate production via transferases and the degradation of several amino acids due to gut microbial metabolism have strong correlations with T2D in Northern China. Moreover, the potential of gut microbiota-based classifiers to identify individuals with a high risk for T2D has been demonstrated in this study. Taken together, our findings have revealed a previously unappreciated association of the gut microbiome with T2D and have also suggested that changes in gut microbiota may be used to identify individuals at high risk for T2D.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
ABSTRACT
The coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has precipitated a global health crisis of unprecedented ...proportions. Because of its severe impact, multiple COVID-19 vaccines are being rapidly developed, approved and manufactured. Among them, mRNA vaccines are considered as ideal candidates with special advantages to meet this challenge. However, some serious adverse events have been reported after their application, significantly increasing concerns about the safety and efficacy of the vaccines and doubts about the necessity of vaccination. Although several fertility societies have announced that COVID-19 mRNA vaccines are unlikely to affect fertility, there is no denying that the current evidence is very limited, which is one of the reasons for vaccine hesitancy in the population, especially in pregnant women. Herein, we provide an in-depth discussion on the involvement of the male and female reproductive systems during SARS-CoV-2 infection or after vaccination. On one hand, despite the low risk of infection in the male reproductive system or fetus, COVID-19 could pose an enormous threat to human reproductive health. On the other hand, our review indicates that both men and women, especially pregnant women, have no fertility problems or increased adverse pregnancy outcomes after vaccination, and, in particular, the benefits of maternal antibodies transferred through the placenta outweigh any known or potential risks. Thus, in the case of the rapid spread of COVID-19, although further research is still required, especially a larger population-based longitudinal study, it is obviously a wise option to be vaccinated instead of suffering from serious adverse symptoms of virus infection.
Magnetic skyrmions, topological‐chiral spin textures, have potential applications in next‐generation high‐density and energy‐efficient spintronic devices for information storage and logic ...technologies. Tailoring the detailed spin textures of skyrmions is of pivotal importance for tuning skyrmion dynamics, which is one of the key factors for the design of skyrmionic devices. Here, the direct observation of parallel aligned elliptical magnetic skyrmions in Pt/Co/Ta multilayers with an oblique‐angle deposited Co layer is reported. Domain wall velocity and spin–orbit‐torque‐induced out‐of‐plane effective field analysis demonstrate that the formation of unusual elliptical skyrmions is correlated to the anisotropic effective perpendicular magnetic anisotropy energy density (Keffu) and Dzyaloshinskii–Moriya interaction (DMI) in the film plane. Structural analysis and first‐principles calculations further show that the anisotropic Keffu and DMI originate from the interfacial anisotropic strain introduced by the oblique‐angle deposition. The work provides a method to tune the spin textures of skyrmions in magnetic multilayers and, thereby, a new degree of freedom for the design of skyrmionic devices.
Néel‐type elliptical magnetic skyrmions are observed in Pt/Co/Ta multilayers with an oblique‐angle deposited Co layer. The formation of elliptical skyrmions is found to be related to the anisotropic effective perpendicular magnetic anisotropy energy density and Dzyaloshinskii–Moriya interaction in the film plane. The results provide a route to tuning the symmetry of skyrmions for related physics study and device applications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A potted soil experiment was conducted to investigate the effects of bensulfuron-methyl (BSM) residue on the growth and photosynthesis of seedlings of a local cucumber variety (Xia Feng No.1). When ...the residue of bensulfuron-methyl in soil exceeded 50μg kg-1, it significantly inhibited the growth of cucumber, chlorophyll content and photosynthetic capacity of cucumber. BSM treatment caused significant decreases in the biomass, chlorophyll content, net photosynthesis rate, stomatal conductance, and transpiration rate, photosystem II (PSII) maximum quantum yield, actual quantum yield, photochemical quenching coefficient, and electron transport rate in cucumber seedlings, but increased the minimal fluorescence yield and dark respiration rate. Moreover, comparisons of the patterns of absorbed light energy partitioning revealed that the fractions of excess and thermally dissipated energy increased with rising concentrations of the BSM residue, but the fraction of PSII photochemistry declined. The BSM residues caused reversible destruction in the PSII reaction centers and decreased the proportion of available excitation energy used in PSII photochemistry. The results suggested that rice or wheat fields sprayed with BSM will not be suitable for planting cucumbers in succession or rotation.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The molecular evolutionary dynamics that shape hantaviruses’ evolution are poorly understood even now, besides the contribution of virus-host interaction to their evolution remains an open question. ...Our study aimed to investigate these two aspects in Hantaan virus (HTNV)—the prototype of hantaviruses and an emerging zoonotic pathogen that infects humans, causing hemorrhagic fever with renal syndrome (HFRS): endemic in Far East Russia, China, and South Korea—via a comprehensive, phylogenetic-dependent codon usage analysis. We found that host- and natural reservoir-induced natural selection is the primary determinant of its biased codon choices, exceeding the mutational bias effect. The phylogenetic analysis of HTNV strains resulted in three distinct clades: South Korean, Russian, and Chinese. An effective number of codon (ENC) analysis showed a slightly biased codon usage in HTNV genomes. Nucleotide composition and RSCU analyses revealed a significant bias toward A/U nucleotides and A/U-ended codons, indicating the potential influence of mutational bias on the codon usage patterns of HTNV. Via ENC-plot, Parity Rule 2 (PR2), and neutrality plot analyses, we would conclude the presence of both mutation pressure and natural selection effect in shaping the codon usage patterns of HTNV; however, natural selection is the dominant factor influencing its codon usage bias. Codon adaptation index (CAI), Relative codon deoptimization index (RCDI), and Similarity Index (SiD) analyses uncovered the intense selection pressure from the host (Human) and natural reservoirs (Striped field mouse and Chinese white-bellied rat) in shaping HTNV biased codon choices. Our study clearly revealed the evolutionary processes in HTNV and the role of virus-host interaction in its evolution. Moreover, it opens the door for a more comprehensive codon usage analysis for all hantaviruses species to determine their molecular evolutionary dynamics and adaptability to several hosts and environments. We believe that our research will help in a better and deep understanding of HTNV evolution that will serve its future basic research and aid live attenuated vaccines design.
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