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The ecologically fragile agro-pastoral ecotone in northern China is characterized by relatively poor arable land quality. Yunzhou District in Datong City, which is situated within this transitional zone, boasts over 600 years of Hemerocallis citrina Baroni cultivation. Exploring the effects of soil physicochemical properties on daylily yield and related agronomic traits is essential for enhancing the ecological and economic value of dominant crops in ecologically fragile areas. Therefore, in this study, we focused on the daylily, a characteristic cash crop that is grown in the agro-pastoral ecotone in Yunzhou District. Physicochemical property measurement and yield estimation were performed using soil samples collected from 37 sites, with Spearman's correlation analysis, one-way analysis of variance with multiple comparisons, path analysis, and stepwise regression analysis used to analyze the generated data. The results showed the following: (1) The pathway analysis of daylily yield with each agronomic trait showed that the BN and PH directly affected the yield of daylily with direct pathway coefficients of 0.844 and 0.7, respectively, whereas the SN indirectly affected the yield of daylily through the BD and PH, with indirect pathway coefficients of 0.827 and 0.566, respectively. (2) A total of four principal components were extracted for the soil factors, of which SMC, ST and BD had large loadings on PC1; OM, TN and pH had large loadings on PC2; AK had large loadings on PC3; and AP had large loadings on PC4. (3) From the principal component regression and stepwise regression, it can be seen that SMC is the most critical factor affecting the yield of daylily, as well as the related agronomic traits, and the results also show that yield prediction was affected by OM, ST, and AK, while BN was influenced by OM and ST, and SN and PH were influenced by AP. Comparing the goodness of fit and significance of the two models, it can be concluded that the stepwise regression model is the optimal model for this study. [ABSTRACT FROM AUTHOR]

The farming–pastoral ecotone in northern China is an ecologically vulnerable area with low-quality arable land, and cash crops are an important economic source for local farmers. Although local governments have introduced supportive policies, there are still several factors that hinder the implementation of the policies: there is a lack of sufficient research on the distribution of specialty crops, and the driving factors for agricultural planting structure adjustment are not yet clear. In this study, the specialty cash crop of the daylily planting industry in Yunzhou District, in the Farming–Pastoral Ecotone in northern China, was selected as the research object. Field surveys were conducted to collect sample points and village-level survey data, which were further combined with Sentinel-1 and Sentinel-2 data, and vegetation indices. Support vector machine (SVM) and random forest (RF) classifiers were utilized to identify daylilies and compare the accuracy using different combinations of input data. Furthermore, the classification results were counted by village, and spatial autocorrelation was used to analyze the spatial distribution pattern of daylilies. Finally, in conjunction with the village-level survey data, Spearman correlation analysis, multiple regression trees (MRT), and random forests were employed to explore the driving factors of daylily cultivation. The results indicate that using an RF classification tree of 300 resulted in the optimal method, as it achieved the highest accuracy for crop classification. The overall accuracy and daylily classification accuracy were 94.6% and 94.75%, respectively. Daylily distributions were mainly concentrated near the Sanggan River, urban areas, and the tourism industry. The distribution area of daylilies in each village was concentrated in 13.4–38.8 hm2. Spatial clustering showed more aggregation of low–low and high–high types. Labor force and daylily yield were identified as the most significant influencing factors. Further analysis of the different regions revealed the importance of industry support policies and technical training. This study provides data to support the distribution of specialty crops in Yunzhou District and a technical basis for adjusting agricultural planting structures. [ABSTRACT FROM AUTHOR]

Bathyarchaeia (formerly Bathyarchaeota) is a group of highly abundant archaeal communities that play important roles in global biogeochemical cycling. Bathyarchaeia is predominantly found in sediments and hot springs. However, their presence in arable soils is relatively limited. In this study, we aimed to investigate the spatial distributions and diversity of Bathyarchaeia in paddy soils across eastern China, which is a major rice production region. The relative abundance of Bathyarchaeia among total archaea ranged from 3 to 68% in paddy soils, and Bathy-6 was the dominant subgroup among the Bathyarchaeia (70–80% of all sequences). Bathyarchaeia showed higher migration ability and wider niche width based on the neutral and null model simulations. Bathy-6 was primarily assembled by deterministic processes. Soil pH and C/N ratio were identified as key factors influencing the Bathyarchaeia composition, whereas C/N ratio and mean annual temperature influenced the relative abundance of Bathyarchaeia. Network analysis showed that specific Bathyarchaeia taxa occupied keystone positions in the archaeal community and co-occurred with some methanogenic archaea, including Methanosarcina and Methanobacteria, and ammonia-oxidizing archaea belonging to Nitrososphaeria. This study provides important insights into the biogeography and niche differentiation of Bathyarchaeia particularly in paddy soil ecosystems. [ABSTRACT FROM AUTHOR]

Summary: Autotrophic carbon dioxide (CO2) fixation by microbes is ubiquitous in the environment and potentially contributes to the soil organic carbon (SOC) pool. However, the multiple autotrophic pathways of microbial carbon assimilation and fixation in paddy soils remain poorly characterized. In this study, we combine metagenomic analysis with 14C‐labelling to investigate all known autotrophic pathways and CO2 assimilation mechanisms in five typical paddy soils from southern China. Marker genes of six autotrophic pathways are detected in all soil samples, which are dominated by the cbbL genes (67%–82%) coding the ribulose‐bisphosphate carboxylase large chain in the Calvin cycle. These marker genes are associated with a broad range of phototrophic and chemotrophic genera. Significant amounts of 14C‐CO2 are assimilated into SOC (74.3–175.8 mg 14C kg−1) and microbial biomass (5.2–24.1 mg 14C kg−1) after 45 days incubation, where more than 70% of 14C‐SOC was concentrated in the relatively stable humin fractions. These results show that paddy soil microbes contain the genetic potential for autotrophic carbon fixation spreading over broad taxonomic ranges, and can incorporate atmospheric carbon into organic components, which ultimately contribute to the stable SOC pool. [ABSTRACT FROM AUTHOR]

Nitrite reduction is regulated by nitrite reductase encoded by nirK and nirS genes. This study aimed to investigate the abundance and composition of nirK- and nirS-containing denitrifiers in response to Spartina alterniflora invasion at the Jiulong River estuary, China. The sediment samples (depth: 0–5.0 and 5.1–20 cm) were collected from 3 vegetation zones, 1 dominated by the exotic plant S.alterniflora, 1 dominated by the native plant Kandelia candel, and 1 dominated by the native plant Cyperus malaccensis, and from an unvegetated flat zone. nirK- and nirS-containing denitrifier population sizes were lower in the invaded and nonvegetated zones than in those dominated by native K.candel and C.malaccensis, which were impacted by depth – vegetation species interaction. The ratios of nirS to nirK abundance ranged from 42.10 to 677.27, with the lowest ratio found for the upper layer in the invaded zone. The nirK-containing denitrifier compositions showed a 35% similarity between invaded zone and others. Most of the sequences of nirK genes recovered from the S.alterniflora zone were specific and distinct from those of nirK genes recovered from other vegetation types; nirS genes in the invaded zone were highly divergent. These results reveal that S.alterniflora invasion has a significant effect on the abundance and composition of both nirK- and nirS-containing denitrifiers, and nirS-containing denitrifiers were less responsive to invasion than nirK-containing denitrifiers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon storage, habitat quality, soil retention, and water yield in the agro-pastoral ecotone of northern China are in an increasing phase from 2000 to 2020. • Diverse ES bundles shift over time, revealing intricate spatiotemporal dynamics. • Socio-ecological drivers shape consistent yet scale-dependent ES patterns. • Propose ecological management strategies at different spatial scales based on ecosystem service bundles. To achieve regional ecological management and sustainable socio-economic development, it is essential to comprehend the intricate and interdependent relationships among various ecosystem services. The Agro-pastoral ecotone of northern China is a typical ecologically vulnerable area. There is limited research on managing multiple ecosystem services to maximize supply based on understanding the complex relationships among ecosystem services. This study used the InVEST model to quantify habitat quality (HQ), soil conservation (SC), carbon sequestration (CS), and water yield (WY) in the Agro-pastoral ecotone of northern China in 2000, 2010, and 2020 at the 5 km grid and county scales. Their trade-off and synergistic effects were explored using Spearman correlation analysis and the Geographically Weighted Regression (GWR) model. In addition, self-organizing mapping was employed to identify ecosystem service bundles at two scales, whereas the geodetector was employed to determine the primary social-ecological drivers of ES. Finally, management strategies are proposed based on the research results to promote regional ecological sustainability. The results indicate that: (1) The four ESs exhibited an increasing trend during the study period. Except for WY, the other three ES demonstrated a similar spatial distribution while remaining relatively stable over time; (2) there is a synergistic effect between CS, HQ, and SC, whereas WY-related ES show trade-off effects; (3) six ES bundles were identified at the 5 km grid scale, and four ES bundles were identified at the county scale; (4) precipitation is a major driving factor for WY and an important driving factor for CS, HQ, and SC. In summary, natural factors have a greater impact on ES than socio-economic factors. Based on the differences in ecosystem service bundles and drivers at different scales, and in conjunction with China's existing environmental policies, corresponding ecological management strategies were proposed, potentially providing a reference for sustainable development of the Agro-pastoral ecotone in northern China. [ABSTRACT FROM AUTHOR]

China has been seriously affected by particulate matter (PM) and gaseous pollutants in the atmosphere. In this study, we systematically analyse the spatio-temporal patterns of PM 2.5 , PM 10 , SO 2 , CO, NO 2 , and O 3 and the associated health risks, using data collected from 1498 national air quality monitoring sites. An analysis of the averaged data from all the sites indicated that, from 2015 to 2018, annual mean concentrations of PM 2.5 , PM 10 , SO 2 and CO declined by 3.2 μg m−3, 3.7 μg m−3, 3.9 μg m−3, and 0.1 mg m−3, respectively. In contrast, those of NO 2 and O 3 increased at rates of 0.4 and 3.1 μg m−3, respectively. Except for O 3 , the annual mean concentrations of all pollutants were generally the highest in North China and lowest in the Tibetan Plateau. The concentrations were generally higher in the north of the country than in the south. In all regions of China, the pollutant concentrations were the highest in winter and lowest in summer, except for O 3 , which showed an opposite seasonal pattern. Overall, the seasonal mean concentrations of all the pollutants (except for O 3) significantly decreased between the same seasons in 2018 and 2015, whereas the seasonal mean O 3 concentrations generally significantly increased, and/or remained at stable levels in all four seasons except for winter. Diurnal variations of all pollutants (except for O 3) exhibited a bimodal pattern with peaks between 8:00 and 11:00 a.m. and 9:00 and 12:00 p.m., whereas O 3 exhibited a unimodal pattern with maximum values between 5:00 and 7:00 p.m. No significant differences in the daily mean concentrations of all pollutants were found between weekdays and weekends in all regions, except for PM 2.5 and PM 10 in Northeast China. In Northwest China and Southeast China, PM 2.5 showed stronger correlations with NO 2 relative to SO 2 , suggesting that NO x emission control may be more effective than SO 2 emission control for alleviating PM 2.5 formation. Compared with 2015, the total PM 2.5 -attributable mortality, number of respiratory and cardiovascular diseases, and incidence of chronic bronchitis decreased overall by 23.4%–26.9% in 2018. In contrast, for O 3 -attributable deaths, there was an increase of 18.9%. Our study not only improves the understanding of the spatial and temporal patterns of air pollutants in China, but also highlights that synchronous control of PM 2.5 and O 3 pollution should be implemented to achieve dual benefits in protecting human health. Image 1 • Hourly concentrations of six air pollutants were analysed at1498 sites in China. • Except O 3 and NO 2 , all the pollutants concentrations decreased annually. • O 3 peaked in the Tibetan Plateau, whereas the other pollutants in North China. • The diurnal variations of all pollutants displayed a bimodal pattern except for O 3. • O 3 pollution should be reduced to maximise the protection of human health. Our study highlights the large variability in the spatial and temporal patterns of air pollutants over China and indicates that O 3 pollution should be given greater consideration. [ABSTRACT FROM AUTHOR]

Autotrophic carbon dioxide (CO 2 ) fixation by microbes is ubiquitous in the environment and potentially contributes to the soil organic carbon (SOC) pool. However, the multiple autotrophic pathways of microbial carbon assimilation and fixation in paddy soils remain poorly characterized. In this study, we combine metagenomic analysis with 14 C-labelling to investigate all known autotrophic pathways and CO 2 assimilation mechanisms in five typical paddy soils from southern China. Marker genes of six autotrophic pathways are detected in all soil samples, which are dominated by the cbbL genes (67%-82%) coding the ribulose-bisphosphate carboxylase large chain in the Calvin cycle. These marker genes are associated with a broad range of phototrophic and chemotrophic genera. Significant amounts of 14 C-CO 2 are assimilated into SOC (74.3-175.8 mg 14 C kg -1 ) and microbial biomass (5.2-24.1 mg 14 C kg -1 ) after 45 days incubation, where more than 70% of 14 C-SOC was concentrated in the relatively stable humin fractions. These results show that paddy soil microbes contain the genetic potential for autotrophic carbon fixation spreading over broad taxonomic ranges, and can incorporate atmospheric carbon into organic components, which ultimately contribute to the stable SOC pool., (© 2020 Society for Applied Microbiology and John Wiley & Sons Ltd.)

The study was conducted to extend research on the reluctance for emotional disclosure to Chinese patients with a variety of types of cancer. A quantitative survey was conducted among 400 cancer patients in China. Statistical analysis revealed that among four confirmed factors on reluctance for emotional disclosure to physicians, no perceived need scored highest, followed by unwillingness to bother, no practical use, and fear of negative impact. Patient distress was negatively associated with no perceived need and no practical use. Patients with low family support scored significantly lower in all factors except fear of negative impact. Education and income affected the factor of no perceived need. Those patients having limited family support and limited education indicated a higher need for emotional support from their physicians and were more likely to open up to them. Cultural traits should be integrated into supportive cancer care research.