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Since 2017, an infectious goose gout disease characterized by urate precipitation in viscera, mainly caused by novel goose astrovirus (GoAstV) infection, has emerged in the main goose-producing region of China. The current challenge in managing goose gout disease is largely due to the absence of a rapid and efficient detection method for the GoAstV pathogen. Notably, the potential application of immunosensors in detecting GoAstV has not yet been explored. Herein, a label-free PEC immunosensor was fabricated by using purchased TiO2 as the photoactive material and antibody against GoAstV P2 proteins as the specific recognition element. First, we successfully expressed the capsid spike domain P2 protein of ORF2 from GoAstV CHSH01 by using the pET prokaryotic expression system. Meanwhile, the polyclonal antibody against GoAstV capsid P2 protein was produced by purified protein. To our knowledge, this is the first establishment and preliminary application of the label-free photoelectrochemical immunosensor method in the detection of AstV. The PEC immunosensor had a linear range of 1.83 fg mL−1 to 3.02 ng mL−1, and the limit of detection (LOD) was as low as 0.61 fg mL−1. This immunosensor exhibited high sensitivity, great specificity, and good stability in detecting GoAstV P2 proteins. To evaluate the practical application of the immunosensor in real-world sample detection, allantoic fluid from goose embryos was collected as test samples. The results indicated that of the eight positive samples, one false negative result was detected, while both negative samples were accurately detected, suggesting that the constructed PEC immunosensor had good applicability and practical application value, providing a platform for the qualitative detection of GoAstV. [ABSTRACT FROM AUTHOR]

Continued urban expansion (UE) has long been regarded as a huge challenge for climate change mitigation. However, much less is known about how UE affects carbon emissions (CEs), especially in the urban agglomerations of the Yellow River Basin (UAYRB), China. In this regard, this study introduced kernel density analysis, the Gini coefficient, and Markov chains to reveal the UE patterns and carbon emissions intensity (CEI) in the UAYRB at the county level, and explored the spatial heterogeneity of the impact of UE on CEI with the geographically and temporally weighted regression model. The results show that both CEI and UE in the UAYRB showed a steady growing trend during the study period. The kernel density of CEI and UE revealed that CEI in the UAYRB was weakening, while the UE rate continuously slowed down. The Gini coefficients of both CEI and UE in the UAYRB region were at high levels, indicating obvious spatial imbalance. The Markov transfer probability matrix for CEI with a time span of five years showed that CEI growth will still occur over the next five years, while that of UE was more obvious. Meanwhile, counties with a regression coefficient of UE on CEI higher than 0 covered the majority, and the distribution pattern remained quite stable. The regression coefficients of different urban landscape metrics on CEI in the UAYRB varied greatly; except for the landscape shape index, the regression coefficients of the aggregation index, interspersion and juxtaposition index, and patch density overall remained positive. These findings can advance the policy enlightenment of the high-quality development of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

China, one of the most populous countries in the world, has suffered the highest number of natural disaster-related deaths from fire. On local scales, the main causes of urban fires are anthropogenic in nature. Yet, on regional to national scales, little is known about the indicators of large-scale co-varying urban fire activity in China. Here, we present the China Fire History Atlas (CFHA), which is based on 19   947 documentary records and represents fires in urban areas of China over the twentieth century (1901–1994). We found that temperature variability is a key indicator of urban fire activity in China, with warmer temperatures being correlated with more urban fires, and that this fire–temperature relationship is seasonally and regionally explicit. In the early twentieth century, however, the fire–temperature relationship was overruled by war-related fires in large urban areas. We further used the fire–temperature relationship and multiple emissions scenarios to project fire activity across China into the twenty-first century. Our projections show a distinct increase in future urban fire activity and fire-related economic loss. Our findings provide insights into fire–climate relationships in China for densely-populated areas and on policy-relevant time scales and they contribute spatial coverage to efforts to improve global fire models. [ABSTRACT FROM AUTHOR]

Surface fine particulate matter (PM 2.5) pollution can be enhanced by feedback processes induced by aerosol–radiation interactions (ARIs) and aerosol–cloud interactions (ACIs). Many previous studies have reported enhanced PM 2.5 concentrations induced by ARIs and ACIs for episodic events in China. However, few studies have examined the changes in the ARI- and ACI-induced PM 2.5 enhancements over a long period, though the anthropogenic emissions have changed substantially in the last decade. In this study, we quantify the ARI- and ACI-induced PM 2.5 changes for 2013–2021 under different meteorology and emission scenarios using the Weather Research and Forecasting model with Chemistry (WRF-Chem), and we investigate the driving factors behind the changes. Our results show that, in January 2013, when China suffered from the worst PM 2.5 pollution, the PM 2.5 enhancement induced by ARIs in eastern China (5.59 µg m -3) was larger than that induced by ACIs (3.96 µg m -3). However, the ACI-induced PM 2.5 enhancement showed a significantly smaller decrease ratio (51 %) than the ARI-induced enhancement (75 %) for 2013–2021, making ACIs more important for enhancing PM 2.5 concentrations in January 2021. Our analyses suggest that the anthropogenic emission reductions played a key role in this shift. Owing to only anthropogenic emission reductions, the ACI-induced PM 2.5 enhancement decreased by 43 % in January, which was lower than the decrease ratio of the ARI-induced enhancement (57 %). The relative change in ARI- and ACI-induced PM 2.5 enhancement in July was similar to the pattern observed in January, caused by anthropogenic emission reductions. The primary reason for this phenomenon is that the decrease in ambient PM 2.5 for 2013–2021 caused a disproportionately small decrease in the liquid water path (LWP) and an increase in the cloud effective radius (Re) under the condition of high PM 2.5 concentrations. Therefore, the surface solar radiation attenuation (and, hence, the boundary layer height reduction) caused by ACIs decreased slower than that caused by ARIs. Moreover, the lower decrease ratio of the ACI-induced PM 2.5 enhancement was dominated by the lower decrease ratio of ACI-induced secondary PM 2.5 component enhancement, which was additionally caused by the smaller decrease ratio of the air temperature reduction and the relative humidity (RH) increase. Our findings indicate that, with the decrease in ambient PM 2.5 , the ACI-induced PM 2.5 enhancement inevitably becomes more important. This needs to be considered in the formulation of control policies to meet the national PM 2.5 air quality standard. [ABSTRACT FROM AUTHOR]

Quantifying the full-volatility organic emissions from cooking sources is important for understanding the causes of organic aerosol pollution. However, existing national cooking emission inventories in China fail to cover full-volatility organics and have large biases in estimating emissions and their spatial distribution. Here, we develop the first emission inventory of full-volatility organics from cooking in China, which covers emissions from individual commercial restaurants as well as residential kitchens and canteens. In our emission estimates, we use cuisine-specific full-volatility emission factors and provincial policy-driven purification facility installation proportions, which allows us to consider the significant impact of diverse dietary preferences and policy changes on China's cooking emissions. The 2021 emissions of volatile organic compounds (VOCs), intermediate-volatility organic compounds (IVOCs), semi-volatile organic compounds (SVOCs), and organic compounds with even lower volatility (xLVOCs) from cooking in China are 561 (317–891, 95 % confidence interval) kt yr -1 , 241 (135–374) kt yr -1 , 176 (95.8–290) kt yr -1 , and 13.1 (7.36–21.0) kt yr -1 , respectively. The IVOC and SVOC emissions from cooking account for 9 %–21 % and 31 %–62 % of the total emissions from all sources in the five most densely populated cities in China. Among all cooking types, commercial cooking dominates the emissions, contributing 54.5 %, 66.2 %, 68.5 %, and 46.7 % to the VOC, IVOC, SVOC, and xLVOC emissions, respectively. Sichuan–Hunan cuisine contributes the most to total cooking emissions among all commercial cuisines. Residential cooking emissions are also important, accounting for 22.2 %–47.1 % of the cooking organic emissions across the four volatility ranges, whereas canteens make minor contributions to each volatility range (<10%). In terms of spatial distribution, emission hotspots mainly occur in densely populated areas and regions with oily and spicy dietary preferences. From 2015 to 2021, national organic emissions from cooking increased by 25.2 % because of the rapid growth of the catering industry, despite being partly offset by the increased installation of purification facilities. Future control measures need to further promote the purification facilities in commercial restaurants and improve their removal efficiency as well as reduce emissions from residential cooking. Our dataset and generalizable methodology serve as valuable resources for evaluating the air quality, climate, and health impacts of cooking sources, and help to formulate effective emission control policies. Our national, multi-year, high-spatial-resolution dataset can be accessed from 10.6084/m9.figshare.23537673 (Li et al., 2023). [ABSTRACT FROM AUTHOR]

Pregnant women with low vitamin D levels tend to have poor clinical outcomes. Meteorological factors were associated with vitamin D. Here, we aimed to study the current status of 25-Hydroxy vitamin D (25(OH)D) concentrations in pregnant women in Kunshan city and investigate the meteorological factors associated with 25(OH)D levels under different seasons. The correlation between meteorological factors and 25(OH)D levels was estimated by cross-correlation analysis and multivariate logistic regression. A restrictive cubic spline method was used to estimate the non-linear relationship. From 2015 to 2020, a total of 22,090 pregnant women were enrolled in this study. Pregnant women with 25(OH)D concentrations below 50 nmol/l represent 65.85% of the total study population. There is a positive correlation between temperature and 25(OH)D. And there is a protective effect of the higher temperature on vitamin D deficiency. However, in the subgroup analysis, we found that in autumn, high temperatures above 30 °C may lead to a decrease in 25(OH)D levels. This study shows that vitamin D deficiency in pregnant women may widespread in eastern China. There is a potential inverted U-shaped relationship between temperature and 25(OH)D levels, which has implications for understanding of vitamin D changes under different seasons. [ABSTRACT FROM AUTHOR]

Background: Porcine circovirus type 2 (PCV2) has caused great economic losses in the global pig industry. There have been published records of wild rats acting as the reservoirs of PCV2 (only PCV2a and PCV2b), but almost all of which were related to the PCV2-infected swine herds. Results: In this study, we carried out the detection, amplification, and characterization of novel PCV2 strains in wild rats that were captured far from pig farms. Nested PCR assay demonstrated that the kidney, heart, lung, liver, pancreas, and large and small intestines of rats were screened positive for PCV2. We subsequently sequenced two full genomes of PCV2 in positive sample pools, designated as js2021-Rt001 and js2021-Rt002. Genome sequence analysis indicated that they had the highest similarity to nucleotide sequences of porcine-origin PCV2 isolates in Vietnam. Phylogenetically, js2021-Rt001 and js2021-Rt002 were a part of the PCV2d genotype cluster, which is a predominant genotype circulating worldwide in recent years. The antibody recognition regions, immunodominant decoy epitope, and heparin sulfate binding motif of the two complete genome sequences coincided with those previously reported. Conclusions: Our research reported the genomic characterization of two novel PCV2 strains (js2021-Rt001 and js2021-Rt002) and provided the first supported evidence that PCV2d could naturally infect wild rats in China. However, whether the newly identified strains have potential for circulating in nature in vertical and horizontal transmission or inter-species jumping between rats and pigs needs further research. [ABSTRACT FROM AUTHOR]

Rapid industrialization has led to a dramatic increase in air pollution. In China, the factors driving the abundance and composition of smog, particularly fine particulate matter, remain poorly understood, and short-term air pollution data are available from few air quality monitoring networks. Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), chemical elements (Mg, Al, Si, S, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Tl, Pb, Bi) were analyzed in Quercus mongolica Fisch. ex Ledeb. tree rings from Harbin, China, in latewood at 5-year resolution over the period 1965–2020. The temporal trend of some elements was influenced by physiological factors, by environmental factors such as pollution, or influenced by both. Mg, K, Zn, Cu, Ni, Pb, As, Sr and Tl showed changes in pollution levels over time. The signal of K, Zn, Ni, Cu and Pb in trees from Harbin statistically did not differ from those at the control site after the 2000s. Our analysis confirmed the success of the undertaken emission reduction measures, which lead to an improvement in China's urban air quality after 2010. However, As increased from 2000 to 2020 in Harbin which is consistent with rising As concentrations in China. Our study proved that dendrochemistry is a reliable tool to monitor the long-term history of pollution and to contribute to extending instrumental records of pollution back in time. [ABSTRACT FROM AUTHOR]

Global aging is getting worse, especially in China, a country with a large population. It is urgently needed to plan the site of new urban elderly care facilities for an aging society. Based on point of interest data and machine learning algorithms, we established a site selection model of urban elderly care facilities for Wuhan in China and selected potential optimal sites for new urban elderly care facilities. We found that 2059 of the 31,390 grids with a resolution of 500 m × 500 m of Wuhan are priority layout grids for new urban elderly care facilities. A total of 635 priority grids were further selected based on the agglomeration degree of the aging population in each street. They are mainly distributed in the areas with a concentrated aging population within the Second Ring Road around the urban centers. Additionally, some outer suburban streets with a relatively high aging degree also require immediate facility construction. The point of interest data and machine learning algorithms to select the location of urban elderly care facilities can optimize their overall configuration and avoid the subjectivity of site selection to some degree, provide empirical support for how to achieve a good configuration of "population–facilities" in space, and continuously improve the science of the spatial allocation of elderly care facilities. [ABSTRACT FROM AUTHOR]

Maize (Zea may L.)–soybean [Glycine max (L.) Merr.] intercropping is popular in many countries because of its high productivity. However, no studies have explored maize–soybean intercropping via bibliometric methods. Taking the Web of Science database, the visualization applications of CiteSpace and VOSviewer were used to visually analyze the literature related to research in the field of maize–soybean intercropping, with the aim of studying keyword hotspots and evolving trends, and analyzing the future research directions. The results showed that the annual number of publications on maize–soybean intercropping showed rapid growth from 2010 to 2021. The top three publishing countries were China, the United States, and India, and the top three institutions were Sichuan Agricultural University, the Ministry of Agriculture and Rural Affairs of China, and China Agricultural University. Th three most popular journals were Field Crops Research, Agronomy Journal, and Indian Journal of Agronomy. Agronomy, multidisciplinary agriculture and plant science were the most popular research categories. A keyword analysis indicated that "maize" was the most popular study area. Crop root coupling processes, biological nitrogen fixation, efficient utilization of resources, carbon sequestration and emission reduction, microbial communities, and interspecific relationships are the current hot research topics. This study review and analyzed the current research hotspots and future research trends to provide an important reference for scientists to better respond to food security issues. Core Ideas: There has been a rapid increase in maize–soybean intercropping research.China, Chinese institutions, and Chinese scholars have conducted much of this research.Maize–soybean intercropping has shown an interdisciplinary distribution.Keywords showed the heterogeneity in maize–soybean intercropping publications across years. [ABSTRACT FROM AUTHOR]

Simple Summary: Desert plants are the main body of species diversity in desert ecosystems and often employ different strategies to adapt to their surrounding environment. In this study, the water conduction strategies of Zygophyllaceae plants along the drought gradient were discussed by dissecting the roots of Zygophyllaceae plants based on their vessel characteristic parameters. The results show that: (1) With the aggravation of drought stress, the water use strategy of Zygophyllaceae plants' roots changed from safety priority to efficiency priority. (2) The root age of Zygophyllaceae plants increased with temperature, and the growth rate showed a downward trend. (3) Altitude mainly influenced plant growth by affecting the temperature and precipitation of arid habitats. The root xylem anatomical characteristics and life history strategies of Zygophyllaceae plants elaborated in the present study may provide a scientific basis for the ecological restoration of vegetation in arid and semi-arid areas of China. Desert plants are the main component of species diversity in desert ecosystems, and studying the anatomy and function of desert plant xylem is of great significance for understanding climate sensitivity and adaptation mechanisms to arid ecosystems. In this study, 11 sampling points were selected in the region starting from the Loess Plateau to the Jungar Basin, the taproot anatomy materials of 9 samples of Zygophyllaceae plants were collected, and the water conduction strategies and spatial distribution characteristics of these species were analyzed. The age, growth rate, vessel number, vessel fraction, vessel area within a fixed measurement range (TVA), MVA, water conductivity (TKp, MKp) and vessel diameter ranged between 1 and 27 years, 43.67 and 678.10 μm/year, 20 and 1952, 4.43 and 26.58%, 8009.62 and 192069.12 μm², 27.63 and 2164.33 μm², 0.417 and 364.97 kg m−1 MPa−1 s−1, 0.000624 and 7.60 kg m−1 Mpa−1 s−1, and 5.57 and 73.87 μm, respectively. The number of root vessels (R = 0.27, p > 0.05) of Zygophyllaceae plants decreased with the decrease in precipitation, and the average vessel area (R = −0.28, p > 0.05) and hydraulic diameter (R = −0.29, p > 0.05) showed an upward trend. This shows that the water hydraulic efficiency priority strategy may be adopted in the root system of Zygophyllaceae plants in severe drought stress condition, and the water hydraulic safety priority strategy may be used in mild drought stress conditions. With the increase in temperature, the root age of Zygophyllaceae plants showed an increasing trend, and the growth rate showed a downward trend, indicating that the radial growth of the roots of Zygophyllaceae plants is mainly affected by temperature. Altitude influences plant growth by affecting temperature and precipitation in arid habitats. The findings of the present study on root xylem anatomical characteristics and life history strategies provides a scientific basis for the ecological restoration of vegetation in arid and semi-arid areas of China. [ABSTRACT FROM AUTHOR]

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Of all forest biomes, boreal forests are experiencing the most significant warming. Drought caused by warming has a dramatic impact on species in boreal forests. However, little is known about whether the growth of trees and shrubs in boreal forests responds consistently to warming and drought. We obtained the tree-ring width data of 308 trees (Larix gmelinii and Pinus sylvestris var. mongolica) and 133 shrubs (Pinus pumila) from 26 sites in northeastern China. According to the climate data from 1950 to 2014, we determined three extreme drought years (1954, 1967, and 2008). The response difference of radial growth of trees and shrubs in boreal forests to drought was compared using resilience index, moving correlation and response analysis. The results showed that high temperature (mean and maximum temperature) in previous and current growing seasons promoted the growth of P. pumila , but inhibited the growth of trees. On the contrary, wetter conditions (higher PDSI) promoted tree growth but were not conducive to P. pumila growth in high latitudes. Moving correlation analysis showed similar results. In addition, water deficit was more likely to inhibit P. pumila growth in low latitudes. The drought resistance of P. pumila was stronger than that of L. gmelinii and P. sylvestris var. mongolica. Therefore, the growth loss and recovery time of P. pumila during drought was less than those of trees. We concluded that L. gmelinii and P. sylvestris var. mongolica are more prone to growth decline than P. pumila after the drought caused by climate warming. In the future climate warming, shrub growth may benefit more than trees. Our findings are of great significance in predicting the future changes in ecosystem composition and species distribution dynamics in extreme climate susceptible areas. [ABSTRACT FROM AUTHOR]

Background: Bats were identified as a natural reservoir of emerging and re-emerging infectious pathogens threatening human health and life. Methods: This study collected 21 fecal samples of Hipposideros armiger in Mengla County of Xishuangbanna Prefecture Yunnan Province to combine one pool for viral metagenomic sequencing. Results: Two nearly complete genomes of parechoviruses, BPeV11 and BPeV20, were sequenced. Genome analysis revealed that BPeV11 and BPeV20 follow a 3-3-4 genome layout: 5′ UTR-VP0-VP3-VP1-2A-2B-2C-3A-3B-3C-3D-3′ UTR. The prevalence of BPev11 and BPev20 by Nested-PCR showed that 1 of 21 fecal samples was positive. Based on amino acid identity comparison and phylogenetic analysis of P1, 2C, and 3D, BPeV11 and BPeV20 were closely related to but distinct from FPeVs. Conclusion: It was probably proposed to be a novel species in the genus Parechovirus of the family Picornaviridae. The isolation of BPev11 and BPev20 from H. armiger in China is the first complete genome of parechovirus isolations from bat feces of the genus Hipposideros. [ABSTRACT FROM AUTHOR]

Appropriate temporal and spatial scales are important prerequisites for obtaining reliable results in studies of wildlife activity patterns and interspecific interactions. The spread of camera‐trap technology has increased interest in and feasibility of studying the activity patterns and interspecific interactions of wildlife. However, such studies are often conducted at arbitrary spatial and temporal scales, and the methods used impose scale on the study rather than determining how activity and species interactions change with spatial scale. In this study, we used a wavelet‐based approach to determine the temporal and spatial scales for activity patterns and interspecific interactions on Amur leopard and their ungulate prey species that were recorded using camera traps in the main Amur leopard occurrence region in northeast China. Wavelets identified that Amur leopards were more active in spring and fall than summer, and fluctuated with periodicities of 9 and 17 days, respectively. Synchronous relationships between leopards and their prey commonly occurred in spring and fall, with a periodicity of about 20 days, indicating the appropriate seasons and temporal scales for interspecific interaction research. The influence of human activities on the activity patterns of Amur leopard or prey species often occurred over longer time periods (60–64 days). Two‐dimensional wavelet analyses showed that interactions between leopard and prey were more significant at spatial scales of 1 km2. Overall, our study provides a feasible approach to studying the temporal and spatial scales for wildlife activity patterns and interspecific interaction research using camera trap data. [ABSTRACT FROM AUTHOR]

Recent temperature rise caused by human activities has led to profound changes in the forest ecosystem. Shrubs play an important role in the boreal forest. However, it is not clear how shrub growth responds to climate change, especially whether there is a difference in the response of shrub at different altitudes to climate change. Here, we developed three ring-width chronologies of Pinus pumila along an altitudinal gradient in the Aokelidui Mountains, northeast China, then analyzed the relationship between the growth of P. pumila and climate at different altitudes. The results showed that the radial growth of P. pumila at low altitude had more prominent climate signals than those at medium and high altitude and was more sensitive to climate change. The chronological similarity was the highest in low and middle altitudes (72.5%, p < 0.01). Summer temperature had a significant negative effect on the growth of shrubs, and summer precipitation was conducive to the formation of wider rings at medium altitude. The warmer winter of the previous year favored P. pumila growth at low and medium altitudes but just the opposite at high altitudes. After rapid warming, the negative correlation between temperature and P. pumila growth in the growing season changed to a positive correlation at high altitude. On the contrary, the relationship between precipitation and P. pumila growth in the growing season changed from a positive to a negative correlation. We also found that the sensitivity of the growth of P. pumila to the Standardized Precipitation Evapotranspiration Index (SPEI) has gradually increased at medium-altitude since the 1980s. Therefore, in recent decades, the effect of moisture on the radial growth of shrub has become more and more important at medium altitudes. At the same time, the temperature rise was beneficial to the growth of P. pumila at low altitude. Our results suggest that the treeline advancement in this area is unlikely to occur in the near future since the shrub at high altitudes is not sensitive to climate warming. [ABSTRACT FROM AUTHOR]

We used viral metagenomics and next-generation sequencing to identify a novel strain of bocaparvovirus in the intestinal tract of tufted deer (Elaphodus cephalophus), tentatively named "Elaphodus cephalophus bocaparvovirus" (ECBOV). A nearly complete genome sequence of 5,354 nucleotides was obtained, which had the typical genome organization and protein motifs of a bocaparvovirus. Sequence comparisons and phylogenetic analysis revealed that ECBOV may be a new ungulate bocaparvovirus. The identification and characterization of viruses in wildlife will facilitate our understanding of genetic evolution and cross-species transmission and thus further reduce the potential threat to human and animal health. [ABSTRACT FROM AUTHOR]

Background In 2016, the first global viral hepatitis elimination targets were endorsed. An estimated one-third of the world's population of individuals with chronic hepatitis B virus (HBV) infection live in China and liver cancer is the sixth leading cause of mortality, but coverage of first-line antiviral treatment was low. In 2015, China was one of the first countries to initiate a consultative process for a renewed approach to viral hepatitis. We present the investment case for the scale-up of a comprehensive package of HBV interventions. Methods A dynamic simulation model of HBV was developed and used to simulate the Chinese HBV epidemic. We evaluated the impact, costs, and return on investment of a comprehensive package of prevention and treatment interventions from a societal perspective, incorporating costs of management of end-stage liver disease and lost productivity costs. Results Despite the successes of historical vaccination scale-up since 1992, there will be a projected 60 million people still living with HBV in 2030 and 10 million HBV-related deaths, including 5.7 million HBV-related cancer deaths between 2015 and 2030. This could be reduced by 2.1 million by highly active case-finding and optimal antiviral treatment regimens. The package of interventions is likely to have a positive return on investment to society of US$1.57 per US dollar invested. Conclusions Increases in HBV-related deaths for the next few decades pose a major public health threat in China. Active case-finding and access to optimal antiviral treatment are required to mitigate this risk. This investment case approach provides a real-world example of how applied modeling can support national dialog and inform policy planning. [ABSTRACT FROM AUTHOR]

Historical temperature reconstructions enable us to understand the long-term thermal variation feature of a region. We developed a tree-ring width chronology of the coniferous species Tsuga dumosa (D. Don) Eichler (Himalayan Hemlock) growing in the northern Gaoligong Mountains, northwestern Yunnan province of China. The climate-tree growth relationship analysis indicated that summer mean temperature was the main limiting factor of the radial growth of Himalayan Hemlock. Accordingly, using a linear regression model, we reconstructed the historical summer mean temperature time series spanning A.D. 1720–2005, which could account for 35.56% of the observedtemperature variance. Based on the reconstruction, the most obvious warme periods were identified as 1715–1730s, 1900–1910, 1920–1940 and 1980–2005, while the main cold episodes were 1740s–1750s, 1810s–1830s, 1910s–1920s and 1940s–1970s. Wavelet and correlation analyses indicated the existence of several interannual (2–4 years and 5.5 years) and decadal (8–12years) cycles in the variation of summer mean temperature, which probably related to El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and solar activity. [ABSTRACT FROM AUTHOR]

The aim of the current study was to track the composition, spatial and temporal distribution charactistics of triazine herbicides in arable soils and corns in typical agricultural regions of Liaoning Province, China. All samples were analyzed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Twelve kinds of triazine herbicides were found including atrazine, simazine, prometryn, propazine, ametryn, metribuzin, simetryn, aziprotryne, cyanizine, atrazine-desethyl, atrazine-desisopropyl and atrazine-desethyl-desisopropyl in the soil samples, of which atrazine, simazine, prometryn, atrazine-desethyl and atrazine-desethyl-desisopropyl were proved to be the predominant species with a high incidence though relatively low contamination level. The maximum concentration of atrazine in the soils was 73.80 µg·kg−1. Five kinds of triazine herbicides were found in corns in the region including atrazine, simazine, prometryn, atrazine-desethyl and atrazine-desethyl-desisopropyl with the detection rate 96.4%, 17.8%, 14.3%, 60.7% and 46.4%, respectively. The maximum contaminant level of atrazine in corns was 12.52 µg·kg−1, which is lower than that regulated in the National Standard of the People's Republic of China (GB2763-2012). [ABSTRACT FROM AUTHOR]

We developed a tree ring-width chronology of Abies georgei at the timber line in the Big Snow Mountain Scenic Area in northwestern Yunnan, China. The climate-tree growth response analysis indicated that temperature was the predominant regulator of A. georgei growth in this region. An annual mean minimum temperature (AMMT) reconstruction spanning A.D. 1837–2016 was developed with a linear regression model (y = 1.0x − 6e − 5) that accounted for 50.7% of the actual temperature variance during the common period (1960–2016). Based on the reconstructed temperature series, the warmer periods were 1840–1845, 1855–1865, 1880–1895, 1945–1965, and from 1995 until the present day, and the cold periods were 1870–1880, 1900–1930, and 1966–1980. By comparing our results with other regional tree ring records from surrounding areas, a distinctive amount of common warm and cold periods were found, indicating the reliability of our temperature reconstruction and suggesting that the climate in the study area was part of a large-scale climate system. [ABSTRACT FROM AUTHOR]

A complete genome sequence of human papillomaviruses (HPV) named as HPV-ujs-21015 was determined by viral metagenomic and PCR methods. The complete genome is 7354 bp in length with GC content of 41.7%, of which the genome was predicted to contain six ORFs (Open Reading Frame, ORF) coding for four early proteins (E7, E1, E4, and E2) and two late proteins (L1 and L2). Phylogenetic analysis based on the complete genome and the L1 protein showed that HPV-ujs-21015 belongs to a type 214 member within genus Gamma-6 papillomavirus. It is the first complete genome of Gamma-6 papillomavirus discovered from pregnant women in China. [ABSTRACT FROM AUTHOR]

The virome in genital tract secretion samples collected from 80 dairy cattle in Shanghai, China, was characterized. Viruses detected included members of the families Papillomaviridae, Polyomaviridae, Hepeviridae, Parvoviridae, Astroviridae, Picornaviridae, and Picobirnaviridae. A member of a new species within the genus Dyoxipapillomavirus and six circular Rep-encoding single-stranded DNA (ssDNA) (CRESS-DNA) viral genomes were fully sequenced and phylogenetically analyzed. The prevalence of bovine polyomaviruses 1 and 2 was measured by PCR to be 10% (8/80) and 6.25% (5/80), respectively. PCR screening also indicated that the novel papillomavirus ujs-21015 and bovine herpesvirus 6 were present in three and two out of the 80 samples, respectively. [ABSTRACT FROM AUTHOR]

We present a 260-year annual Palmer drought severity index (PDSI) reconstruction based on a tree-ring width chronology of Scots pine (Pinus sylvestris var. mongolica) from four sample sites in the central Daxing'an Mountains, northeast China. The reconstruction equation explained 38.2% of the variance of annual PDSI in the calibration period from 1911 to 2010. Our reconstruction confirmed the local historical documents and other nearby hydroclimate reconstructions. Drought in the 1920s-1930s was more severe in the Daxing'an Mountains than in the surrounding areas. A slight moisture increase was identified in the study area, while a warm-dry pattern was found in the west-central Mongolian Plateau (mildly drier) and its transition zones: the west-central Mongolian Plateau (severely drier). Overall, the variation of drought in the Daxing'an Mountains and its relationship with surrounding areas may be affected by the Pacific or Atlantic oscillations (e.g., ENSO, PDO, AMO, NAO and SNAO), which can affect the Asian monsoon, change the local temperature and precipitation, and lead to drought. [ABSTRACT FROM AUTHOR]

In recent years, the continuous development of metagenomics has revealed that in addition to the digestive tract, some viruses are also common in mammalian blood. To explore and monitor potential novel viruses, in April 2015, a blood sample was collected from a healthy captive giant panda at the Chengdu Research Base of Giant Panda Breeding in Sichuan Province, China. The genomes of 25 different anelloviruses containing the complete ORF1 region have been identified. The BLASTp results showed that the amino acid sequence identity of these viruses with the best match in GenBank ranged from 27.15% to 41.29%. Based on phylogenetic analysis and SDT (Species Demarcation Tool) analysis of the complete ORF1 regions of these 25 viruses, these sequences were deduced to represent one or several novel virus genera or species. This virological study has increased our understanding of the diversity of anelloviruses in the blood of giant pandas, but further laboratory analysis is needed to verify its possible pathogenicity. • Metagenomics reveals viruses in healthy mammalian blood, including giant pandas. • Blood from captive pandas discovered 25 anelloviruses, suggesting new virus possibilities through phylogenetic analysis. • Phylogenetic analysis suggests that these viruses may represent one or several novel virus genera or species. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides and polychlorinated biphenyls in surface soils of Changbai Mountain, Northeastern China, have been quantified by gas chromatography with electron capture detector and the altitude distributions and possible pollution sources were analyzed. The concentrations of ∑HCHs, ∑DDTs and ∑PCBs were in the range of 3.09-25.6, 0.96-19.4 and 7.32-26.1 ng/g dw, respectively. The concentration of α-HCH, β-HCH, p,p′-DDT, p,p′-DDE, PCB 101, 138, 153, and 180 showed increasing trends with altitude. ∑PCBs in surface soils of Changbai Mountain were significantly higher than that in Chinese background areas. The concentration of lower volatile PCB isomers showed positive correlation with altitude. These pollutants may originate from the adjacent industrial and agricultural areas via atmospheric transport and cold-trapping effect through wet precipitation. Additional, DDTs may cause a certain potential ecological risks on birds and soil organisms and the usage of lindane in the adjacent areas cannot be excluded in Changbai Mountain. [ABSTRACT FROM AUTHOR]

ABSTRACT High-resolution tree-ring records covering past centuries in the western Sichuan Plateau of China are scarce, yet essential for developing a complete understanding of the regional patterns of climate change for the Tibetan plateau. This paper presents a temperature reconstruction for the Wolong Natural Reserve of the western Sichuan Plateau based on a tree-ring width chronology of a cypress species ( Sabina saltuaria) endemic to the Tibetan plateau. The annual (prior October to current September) temperature reconstruction, which spans from 1840 to 2011, was developed using a linear regression model. The reconstruction explains 54.1% of the actual temperature variance during the calibration period from 1956 to 2010. The noteworthy warming periods of the reconstruction occurred between 1864-1882 and 1927-1960, while the most pronounced cold episodes were found between 1886-1926, 1788-1822, and 1961-1996. Spectral analysis revealed the existence of multi-decadal, decadal, and annual cycles that might correspond to the related cycles of Atlantic Multidecadal Oscillation, solar activity, and ENSO-type variability, respectively. [ABSTRACT FROM AUTHOR]

Recombination is a well-known phenomenon for enteroviruses. In the present study, a novel recombinant HEV-B strain (ChZJ-1) was found in a 2-year-old child with diarrhea in Zhenjiang, China. The whole genome of ChZJ-1 was determined. Recombination and phylogenetic analysis revealed that ChZJ-1 might have been produced by recombination between coxsackievirus B5 and echovirus 18. [ABSTRACT FROM AUTHOR]

The levels of DDTs, HCHs and PCBs in topsoil, cereal and irrigation water from typical industrial and agricultural areas of Jilin Province in Northeastern China were evaluated by using gas chromatography coupled with an electron capture detector. The amount of ∑OCPs and ∑PCBs found in topsoils ranged from 24.7 to 98.0 and 17.2 to 98.7 ng g, respectively. The geometric means of ∑HCHs, ∑DDTs and ∑PCBs in rice stem samples were 28.9, 32.4 and 49.0 ng g, respectively. The average level of total OCPs concentration in rice field water in Meihekou area (0.849 ng g) is higher than that in Jilin area (0.178 ng g) and all OCPs concentrations in rice field water met the water quality standards for Grade I regulated by China's national environmental quality standard of surface water. [ABSTRACT FROM AUTHOR]

The contamination level of T-2 and HT-2 toxin in cereal crops from Aba area in Sichuan Province of China was investigated by rapid liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results revealed the high incidence of T-2 and HT-2 toxin and relatively low contamination level in the samples. The incidence of HT-2 toxin was 49.74% and its average level was 3.746 μg/kg. The incidence of toxin was 11.64% and the average level was 0.565 μg/kg. The maximum of T-2 and HT-2 toxin concentration was 3.332 and 34.510 μg/kg, respectively. In addition, contaminated samples not only included homegrown products, but included external purchased rice and flour, which may be attributed to bad storage environment and sanitary conditions. [ABSTRACT FROM AUTHOR]

Abstract: Solar activity is one of the most important driving forces of the global climate and environment change. However, little is known about how this force is influencing the earth''s climate system due to short solar activity records. A tree-ring chronology of Abies georgei var. smithii at Sygera Mountain in southeast Tibet was developed and used to investigate solar activity signals by spectral, wavelet and cross-wavelet analyses. The results showed that fluctuations in tree-ring data coincided well with variations in sunspot numbers. Periodicities of 5.3–5.1, 11.2–11.1, 20.5, 73, and 204.1 years may be related to solar activity of the second harmonic of the Schwabe, Schwabe, Hale, Gleissberg, and Suess cycles. The cross-wavelet analysis between tree-ring data and sunspot numbers indicated that the cross power around the 11-year solar cycle is more significant during periods of high solar activity than low solar activity, and the significant 22-year solar cycle is also found. Cross-correlation analysis between these two series showed a significant relationship with a time lag of about 13 years and a non-stationary phase relationship. We therefore propose that solar activity modulated climatic conditions and tree growth by influencing surface temperature through variations in radiation energy and monsoonal precipitation on the Tibetan Plateau. [Copyright &y& Elsevier]

Prior research on tree line dynamics has primarily been based on field inventory data, and little is known about the potential for using remotely sensed imagery to detect change. The present study developed a new methodology by combining remote sensing and field survey data to examine dynamics of the pristine forest in the tree line area on Changbai Mountain in Northeast China over the past two decades. The new method normalized remote sensing data by using the adjacent old-growth coniferous forest (close to climax) below the tree line as the reference (assuming steady state) to eliminate various potential errors associated with different satellite sensors, atmospheric conditions and seasonal vegetation changes. Specifically, we used a ratio of normalised difference vegetation index (NDVI) between the tree line forest (birch) and the referenced old-growth coniferous forest, as well as a ratio between the interface forest against the referenced coniferous forest, to investigate growth dynamics of the tree line forest from 1977 to 1999. The interface forest is distributed between the tree line forest and non-forest zone. Compared with traditional methods using remote sensing data, the new method has higher sensitivity to tree line dynamics. We found that the tree line delineated from satellite imagery had shown no shift in the past decades. However, the NDVI ratio of tree line forest against the reference forest increased from 0.9 to 1.2 from 1977 to 1999, and the ratio of interface forest against the reference forest increased from 0.83 to 0.98, indicating that growth of the tree line forest apparently exceeded that of the reference coniferous forest and had grown denser. Field surveys also supported the conclusion from remote sensing results that the tree line forest on Changbai Mountain has grown denser in the past decades. From 1980 to 2002, basal area of the tree line forest increased 35% (from 18.8 to 25.3 m2 ha-1); at the same time the NDVI ratio increased about 33%. This study suggests that it is possible to monitor growth of the tree line forest based on multi-temporal remote sensing images. We speculate that global warming may have contributed to the observed rapid growth of the tree line forest because temperature is a major limiting factor among climatic variables in the tree line forest and effect from other factors, such as fire, harvesting and snow and wind damage, were not evident in this protected area in the past decades. [ABSTRACT FROM AUTHOR]

(1) Background: Water transport systems play an important role in maintaining plant growth and development. The plasticity responses of the xylem anatomical traits of different species to the environment are different. Studies have shown that there are annual growth rings in the secondary root xylem of perennial herbaceous species. Studies on xylem anatomical traits, however, have mainly focused on woody species, with little attention given to herbaceous species. (2) Methods: We set 14 sampling sites along a rainfall gradient in arid and semiarid regions, and collected the main roots of native (Potentilla) and non-native (Medicago) perennial forbs. The xylem anatomical traits of the plant roots were obtained by paraffin section, and the relationships between the xylem traits of forbs were analyzed by a Pearson correlation. (3) Results: In the fixed measurement area (850 μm × 850 μm), the vessel number (NV) of Potentilla species was higher than that of Medicago species, while the hydraulic diameter (Dh) and mean vessel area (MVA) of Potentilla species were lower than those of Medicago species. With the increase in precipitation along the rainfall gradient, the Dh (R2 = 0.403, p = 0.03) and MVA (R2 = 0.489, p = 0.01) of Medicago species increased significantly, and NV (R2 = 0.252, p = 0.09) decreased, while the hydraulic traits of Potentilla species showed no significant trend with regard to the rainfall gradient. (4) Conclusions: The hydraulic efficiency of non-native Medicago forbs was higher than that of native Potentilla forbs, and the hydraulic safety of native Potentilla forbs was higher than that of non-native Medicago forbs. With the decrease in precipitation, the hydraulic strategies of non-native Medicago forbs changed from efficiency to safety, while native Potentilla forbs were not sensitive to variations in precipitation. [ABSTRACT FROM AUTHOR]

Based on the analysis and study of mineral composition, structure, and major and trace elements, this paper deals with element geochemical characteristics and transformation from primary ore into oxidized ore in the Erzhe gold deposit, Sichuan. Some grounds are provided to constrain the transformation of primary ore to oxidized ore. [ABSTRACT FROM AUTHOR]

Focuses on a study about the metallogenic mechanism of Tianbaoshan lead-zinc deposits found in Sichuan Province, China. Geological setting of the mineral deposits; Geological features of the ore district; Physicochemical condition of mineralization.

Focuses on the quality of educational practices in China. Methods in implementing quality education; Perceptions of teachers and parents regarding the quality of education; Influence of higher authorities on the inferior quality of education; Problems in implementing genuine quality education.

Northeast China has suffered many serious droughts, with loss of agricultural production. A lack of long-term monitoring data has hindered our understanding of drought characteristics and mechanisms. The moisture-related history of the region was investigated by constructing a tree-ring cellulose δ18O chronology for the period 1752–2015 using samples collected from four Korean pine (Pinus koraiensis) trees in eastern NE China. Results indicate that tree-ring δ18O values are significantly correlated with summer (June–September) precipitation, relative humidity, and drought severity. The tree-ring δ18O chronology accounts for 50.7% of the observed variance in summer relative humidity and was used to reconstruct regional relative humidity levels back to 1752. Compared with previous reconstructions of drought-related changes in NE China, the reconstruction reveals more high- and low-frequency variability, with two drought periods during the 1750s–1820s and 1960s–2015, and a wet period during 1820–1960. Regional drying trends is mainly influenced by a weakened East Asia summer monsoon (EASM), with both drought periods being concurrent with high temperatures and a weak EASM. Together with the global warming trend, the increasing temperature and associated precipitation reduction in NE China indicates increasing likelihood of drought for the region in future. [ABSTRACT FROM AUTHOR]

• Drought in early summer mainly limited Dahurian larch growth at its southern margin. • Warming after the 1980s led to growth decline at permafrost & non-permafrost sites. • Drought in June caused intra-annual density fluctuations (IADFs) in earlywood. • Permafrost melting enhances larch growth but leads to less IADFs in boreal forests. Permafrost melting due to climate warming in recent decades has produced significant effects on forest ecosystems, especially the boreal biome at its southernmost limit in Asia. How this warming affects wood formation of trees at intra-annual resolution is unclear, yet is crucial for assessing the impact of permafrost melting on boreal forest growth. In this study, we compared the radial growth and intra-annual wood density fluctuations (IADFs) of Dahurian larch (Larix gmelinii Rupr.) at a permafrost (PF) and a non-permafrost (NPF) site at the southernmost permafrost limit in northeast China and quantified their relationships with climate factors. Drought in early summer was the main factor limiting growth of Dahurian larch. The basal area increment (BAI) of trees at both sites increased initially and then decreased in the 1980s, probably in response to warm-dry climate conditions. Earlywood IADFs (IADF-E) occurred in 14.0% and 9.3% of dated rings at the NPF and PF sites, while the frequency of latewood IADFs (IADF-L) was 6.8% and 2.7% at these two sites. The frequency of IADF-E in trees at both sites was positively and negatively related to June temperatures (and vapor pressure deficit) and precipitation, respectively, suggesting drought stress in June triggered the formation of IADF-E. The IADF-Ls were probably formed in response to warm temperatures in the late growing season. A higher BAI and a lower frequency of IADF-Es of trees at the PF site than at the NPF site indicated that permafrost melting could alleviate drought stress in early summer and promote radial growth of Dahurian larch. This greatly improved forest carbon sequestration and wood quality of some northeastern Asian boreal forests may offset to some extent the adverse effects of warming-drying climates at some sites of northeast Asia. Larch IADF-Es recorded extreme droughts in early summer, giving us a new sight for reconstructing high-frequency extreme climate events. If climate warming continues, the benefits of permafrost melting will gradually disappear and even turn negative due to warmer-dryer climate conditions. Our findings provide valuable information for boreal forest management and conservation under future global warming. [ABSTRACT FROM AUTHOR]

Limited arable land area and deteriorating soil health in smallholder farmers' fields of subtropical regions in China have led to an urgent demand for sustainable production practices with greater land productivity and nutrients use efficiency. A group of field experiments at three locations (Yaan, Lezhi and Renshou) in two consecutive years of 2012–2013 were conducted to study crop production and nutrients recovery of maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) in monocropping and additive relay intercropping systems. The results showed that the total crop yields of the 2:2 maize-to-soybean wide-narrow row spacing planting pattern (RIwn) were significantly higher than that of the 1:1 maize-to-soybean equal row spacing planting pattern (RIe), and the average land equivalent ratios (LER) of the grain yield were 1.79 and 1.49 for the RIwn and RIe, respectively. The nitrogen (N), phosphorus (P) and potassium (K) recovery efficiency calculated by the ratios of crop nutrients removed and fertilizer input indicated that the RIwn had a higher nutrients recovery than the RIe due to proper spacing between maize and soybean rows and higher soybean yield in RIwn. In terms of the amount of fertilizer applied, based on this experiment, P should be reduced in maize plantings and increased in soybean plantings to maintain the balance of soil P. Considering the higher temperatures during the soybean vegetative growth phase, N fertilizer inputs should be controlled to prevent excessive soybean growth. In addition, excess K was taken up in the crop biomass, maybe the straw should be returned to the field to maintain soil K fertility sustainable for the long term. [ABSTRACT FROM AUTHOR]

Abstract Background and aim Chronic hepatitis C is a major global health challenge. China has the world's largest burden of hepatitis C and related liver disease, with several groups having an increased risk of acquiring hepatitis C virus (HCV) infection. We undertook a systematic review in Chinese and English literature to determine the seroprevalence of anti-HCV among men who have sex with men (MSM), sex workers, people who use drugs (PWUD) and migrant workers in China. Methods We searched three Chinese databases (CNKI, Wanfang and Chongqing VIP Information) and four English databases (Pubmed, EMBASE, Global Health and CINAHL) for studies published between 2010 and 2015. Included were 89 studies for MSM, 112 for sex workers, 11 for migrant workers, 94 for people who inject drugs (PWID) and 67 for non-injectors. Random-effect models pooled estimates of anti-HCV seroprevalence in each population and a meta-regression model examined the relationship between anti-HCV seroprevalence and injecting drug use. Results The overall pooled seroprevalence of anti-HCV among MSM was 0.67% (CI 95 0.51–0.86); for sex workers 0.65% (CI 95 0.53–0.77); for migrant workers 0.48 (CI 95 0.20–0.85); for IDUs 72.41% (CI 95 68.71–75.97); among non-injectors 25.07% (CI 95 21.51%–28.80%). Our meta-regression model predicted that the seroprevalence of anti-HCV among PWID increased by 8.6% for each 10% increase seroprevalence of reporting ever having injected drugs. Conclusions Overall, seroprevalence of HCV infection is high among PWUD, especially those who inject. Lower HCV seroprevalence (<1%) was found among MSM, sex workers and migrant workers. Our estimates for IDU seroprevalence are higher than that from the national surveillance system, though estimates for other at-risk populations are similar. [ABSTRACT FROM AUTHOR]

With the intensification of climate warming, more frequent and hotter droughts are a significant risk to forest ecosystems around the globe, including temperate biomes. To accurately predict the response of forests to drought, it is necessary to provide comprehensive information on the resilience of tree growth, its spatiotemporal changes and drivers. This information is often lacking for broadleaf species in temperate regions. To fulfill this aim, we analyzed 3177 ring-width series from 1981 trees covering 40 sites for four dominant broad-leaf tree species (Fraxinus mandshurica, Phellodendron amurense, Juglans mandshurica , and Quercus mongolica) in temperate forests in northeastern China. We quantified the resilience (resistance and recovery) of tree growth to extreme droughts. Minimum temperatures in most seasons and warm conditions and drought stress in early summer were the main factors limiting growth. Among the four tree species, Q. mongolica had the weakest growth resistance to drought and the fastest growth recovery from drought. Juglans mandshurica had a significantly (p < 0.05) higher drought resilience than F. mandshurica and P. amurense. Tree resilience presented a clear spatial pattern driven by differences in site condition and local climate. The resistance (recovery) to drought decreased (increased) with increasing latitude and longitude, and increased (decreased) with elevation. Q. mongolica exhibited a decrease in resistance and increase in recovery through time, whereas the other three tree species showed the opposite pattern. Fraxinus mandshurica, J. mandshurica , and Q. mongolica had high resistance (recovery) in warmer-wetter (colder-drier) regions. In contrast, P. amurense had reduced recovery in cold sites and low resistance in warm sites. The resistance and recovery indices of these sympatric tree species confirmed that different tree species have distinct strategies to cope with drought that is influenced by tree condition and local environment. The influence of biogeographical factors is often more important than other factors and should be considered when studying forest resilience to drought. [ABSTRACT FROM AUTHOR]

• With the succession, P limitation gradually weakened and N limitation increased. • The C: N: P of soil enzymes gradually tended to 1:1:1 in the later succession. • Moisture was the most important of the variables selected effect on EEA. • Soil nutrients decreased with the secondary succession. Extracellular enzymes are the proximate agents of organic matter decomposition, and its activity can be used as an indicator of microbial nutrient demand. The secondary succession of ecosystem will change the soil properties and microbial community structure, which will affect the nutrient cycle and stability of the ecosystem. However, the research on the changes of soil enzymes during the succession in the boreal forest ecosystems is still lack of insight. Using the method of 'space-for-time substitution', we selected four habitats (including grassland, Betula platyphylla forest, Larix gmelinii and Betula platyphylla mixed forest and Larix gmelinii forest) in Greater Khingan Mountains northeastern China to represent the secondary successional sequence of boreal forests, and studied the response mechanism of soil enzyme activities and microbial nutrient limitation to secondary succession of ecosystem after burning. The results showed that during the succession, phosphorus (P) limitation gradually weakened, nitrogen (N) limitation gradually strengthened, and the ratio of carbon (C): N: P of soil enzymes gradually tended to 1: 1: 1. With the progress of succession, C (BG, β-1,4-glucosidase; CBH, β-D-cellobiosidase), N (NAG, β-1,4-N-acetylglucosaminidase; LAP, L-leucine aminopeptidase) related enzyme activity increased and P (AP, acid phosphatase) related enzyme activity did not change significantly. During the secondary succession of ecosystem after burning, the soil microbial community maintains homeostasis, and the nutrient limitation of microorganisms largely depends on the content and stoichiometry of soil nutrients. [ABSTRACT FROM AUTHOR]

China purchases around 62% of the soybean that is traded internationally and is currently only 14.3% self-sufficient, which strains the global food supply. A key question is to what extent China can produce soybeans to meet its demand. Here we used 3 years of data for 26 soybean cultivars across 146 locations in China, combined with APSIM modeling, to quantify soybean yield spatial variations and the impact of varietal and climate changes on soybean yield potential. We further analyzed the key drivers of national soybean production and explored a potential solution to increase national soybean production with maize-soybean strip intercropping system based on data from 32 locations in the past 10 years. The results showed that the contrasting climate conditions across regions in China resulted in diverse maturity types of soybean cultivars, ranging from MG000 to MGⅧ, with grain yield ranging from 1.4 t ha−1 to 4.5 t ha−1. The key climate drivers are temperature at high latitude cool regions and radiation at low latitude hot and humid regions. The key physiological trait for increasing yield is grain number that is closely related to post-anthesis growth. There exists an obvious yield gap between potential yield and actual yield. At national level, total soybean productivity was limited by planting area due to competing maize crop. It remains difficult for soybean to replace maize due to economic competitiveness. However, maize-soybean strip intercropping offers a sustainable solution to produce an additional soybean crop with around half of the yield of a sole soybean while maintaining the current maize yield. This would enable to potentially produce additional 67.4 million tons of soybean yield each year, with minimum reduction of maize yield (land equivalent ratio of maize =0.96). Fully closing the gap between actual unit yield and potential yield level would only increase national soybean production by 8 million tons. Further increase in production rely on increasing soybean planting area is unrealistic due to the more profitable maize crop. Maize-soybean strip intercropping offers a sustainable solution to potentially produce additional 67.4 million tons of soybean yield while maintaining the current maize yield. • We used APSIM NG model to quantify the impact of varietal and climate changes on soybean yield potential. • Grain yield of soybean ranging from 1.4 t ha-1–4.5 t ha-1 across regions in China. • The key climate drivers and physiological trait for increasing soybean yield have been identified. • Maize-soybean strip intercropping would enable to potentially produce additional 67.4 million tons of soybean yield. [ABSTRACT FROM AUTHOR]

• Moisture is the main climatic factor limiting Pinus tabuliformis wood formation. • Moisture limits earlywood and latewood growth at different stages of leaf growth. • Climate-driven adjustments in tree-ring anatomy are mainly found in earlywood. • P. tabuliformis in drier areas prioritizes hydraulic safety to survive in droughts. • P. tabuliformis in wet areas enhances hydraulic efficiency to adapt to warming. Northern China is experiencing pronounced warming and drying, with potentially dire implications for the health of the region's forests. It is of the highest importance to explore the growth response mechanisms of Pinus tabuliformis Carr., the important natural conifer in northern China, to identify the appropriate forest management practices. We used the xylem anatomical traits in 11 temperate P. tabuliformis forests distributed along a transect in northern China to investigate the potential climate factors driving earlywood and latewood formation, the timing of maximum climate sensitivity, and xylem anatomical adjustments. Our results indicated that relative humidity is the main climate factor limiting P. tabuliformis growth. The water stress resulting from the increase in surface and atmospheric temperature has a significant effect on the formation of earlywood. However, only the increase in surface temperature significantly affected the formation of latewood. Earlywood formation is most sensitive to climate around the 150th day of the year, which is when P. tabuliformis grows most vigorously. The most serious impact of water stress on latewood formation occurs around the 200th day, i.e., when both temperatures and P. tabuliformis growth are at their highest. Climate-driven adjustments in tree-ring anatomical structure are found primarily in earlywood rather than in latewood. In a continuously warming climate, the adjustment of xylem anatomical structure of P. tabuliformis will balance between hydraulic efficiency and safety and differ in dry and wet areas. Frequent severe droughts in dry areas can enhance hydraulic safety and induce P. tabuliformis to form smaller lumens and thicker cell walls (higher rTSR) to survive. P. tabuliformis in wet areas can improve hydraulic efficiency by forming larger lumens and thinner cell walls (lower rTSR) to face moderate droughts. Considering more frequent droughts in the future, forest managers should pay enough attention to the moisture conditions when earlywood formation occurs. [ABSTRACT FROM AUTHOR]

• Significant declines in radial growth of trees were found. • Growth responses of Pinus massoniana to climate varied with elevation. • Drought was the most important factor influencing radial growth. • Moisture had a stronger limiting effect on Castanopsis eyrei than on P. massoniana. Rapid warming and increasing drought intensity are exposing forest ecosystems to increasing stress, challenging silvicultural decision-making. Tree growth-climate relationships may provide valuable information on tree species' adaptive potentials. However, it is not clear how subtropical trees will respond to climate change. Here, we present a dendrochronological study on Pinus massoniana and Castanopsis eyrei growing at two elevations (400 m and 890 m) at the northern Luoxiao Mountain in China to reveal their adaptability to climate change. Results show that long-term drought caused by rapid warming and reduced precipitation after 1997 led to a significant (p < 0.05) decline trend in radial growth of trees at all sites except low elevation P. massoniana. Temperatures in almost all seasons were significantly negatively correlated with the radial growth of C. eyrei. The radial growth of P. massoniana at high elevation was significantly positively correlated with relative humidity and negatively correlated with vapor pressure deficit. The relationship between relative humidity and radial growth of P. massoniana at high elevation showed an increasing trend with time, while P. massoniana at low elevation showed the opposite. At the two elevations, the relationships between the radial growth of C. eyrei and precipitation gradually increased, and the relationships with the temperature gradually weakened. The elevation- or hillslope-related hydrothermal redistribution caused the variations in species-specific growth-climate relationships. Our results suggested that large-scale planting of P. massoniana and C. eyrei in the subtropical area of south China is not effective for wood production or carbon sequestration, and both species- or elevation-related tree growth-climate relationships should be considered in forest management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eco-efficiency of cultivated land use (EECLU) is evaluated. • Both carbon sequestration and carbon emissions are considered for measuring EECLU. • Super-efficiency SBM-DEA with undesirable output & panel data analysis are used. • Size has positive impact on the EECLU. • Shape complexity and patch fragmentation have negative impacts on the EECLU. With China's rapid urbanization and socioeconomic development, cultivated land has been experiencing continuous reduction, spatial shift, and ecological degradation in the past few decades, coupled with the decreasing and aging agricultural labor force, thus improving cultivated land utilization efficiency while minimizing associated environmental impacts is one of the major challenges facing China. This study first establishes an index system to access the eco-efficiency of cultivated land use (EECLU) considering both carbon sequestration and carbon emissions, next, employs the Super-SBM model to evaluate the spatial–temporal characteristics of EECLU, then, uses landscape metrics to describe landscape pattern dynamics of cultivated land, and finally conducts panel data analysis to investigate the relationship between landscape pattern changes and the EECLU variations. This framework was applied to Jiangsu Province, a major grain-producing area with a developed economy. The results showed that the average EECLU of the counties in rural Jiangsu from 2000 to 2020 slightly decreased, most counties were in the medium–low efficiency range (0.6–0.8), and Southern Jiangsu generally has the lowest EECLU values while Central Jiangsu has the highest. The total area and the average patch sizes of cultivated land have significantly positive impacts on EECLU, while the shape complexity and patch fragmentation have significantly negative impacts on EECLU. Therefore, comprehensive low-carbon strategies and better management and technology in the agricultural sector are needed to further improve EECLU. On the premise of protecting the total area of cultivated land, larger and more aggregated land patches should be promoted in the land consolidation process, and the cultivated land targeted for occupation or compensation should be able to simplify the overall shape of cultivated land patches. [ABSTRACT FROM AUTHOR]

• The response of growth to water stress increased with permafrost degradation. • Effect of permafrost degradation on growth is more serious on slope than in gully. • The improvement of intrinsic water-use efficiency can't prevent growth decline caused by drought stress. • In the mild degradation area, larch may benefit from prolonged growing season and increased CO 2. The degradation of permafrost caused by climate warming accelerates the infiltration and evaporation of water, destroys the hydrological system, and increases the drought stress of boreal forests. However, how climate warming and permafrost degradation affect intrinsic Water Use Efficiency (iWUE) and tree growth is not fully understood. Using tree-ring width and stable carbon isotope composition (δ13C) data, we analyzed the growth and iWUE of Larix gmelinii on slopes and gullies in three different permafrost degradation areas in Daxing'an Mountains, China. The results showed that the iWUE of L. gmelinii increased significantly in all areas from 1900 to 2015. Radial growth and the ratio of intercellular (C i) and ambient (C a) CO 2 concentration was significantly negatively correlated with temperature and positively correlated with Palmer Drought Severity Index (PDSI) in severe degradation permafrost areas. Meanwhile, radial growth (basal area increment, BAI) has decreased significantly in recent 40 years, and the decline rate of radial growth in slope topographies was higher than that in gully topographies. Growing season temperature was generally positively correlated with iWUE, but negatively correlated with the radial growth of L. gmelinii. The increase of iWUE was negatively correlated with the radial growth of L. gmelinii. The response of BAI, iWUE, and C i / C a to temperature rise and water change was weak in the mild degradation area, and radial growth still increased. In severe and moderate degradation areas, tree physiology (iWUE and C i / C a) was driven by temperature and PDSI, indicating that L. gmelinii adopted a conservative water-saving stomatal strategy, and increasing iWUE did not promote tree growth. Although the water use efficiency of L. gmelinii in the southern edge of permafrost area increased with the increase in temperature, it may face more serious drought stress and growth decline in the future. [ABSTRACT FROM AUTHOR]

Abstract: We explore the potential of tree-ring cellulose δ 18O and δ 13C records for reconstructing climate variability in the southeast Tibetan Plateau. Our sampling strategy was designed to investigate intra and inter-tree variability, and the effects of the age of tree on δ 18O variation. We show that intra-tree δ 13C and δ 18O variability is negligible, and inter-tree coherence is sufficient to build robust tree-ring δ 18O or δ 13C chronologies based on only four trees. There is no evidence of an age effect regarding δ 18O, in contrast with tree-ring width. In our warm and moist sampling site, young tree δ 13C is not clearly correlated with monthly mean meteorological data. Tree-ring δ 18O appears significantly anti-correlated with summer precipitation amount, regional cloud cover, and relative humidity. Simulations conducted with the ORCHIDEE land surface model confirm the observed contribution of relative humidity to tree cellulose δ 18O, and explain the weak correlation of δ 13C with climate by the non-linear integration linked with photosynthesis. Altogether, the tree-ring cellulose δ 18O is shown to be a promising proxy to reconstruct regional summer moisture variability prior to the instrumental period. [Copyright &y& Elsevier]

Abstract: A new insect nodavirus is isolated from Pieris rapae larvae in Wuhan city, China and tentatively designated Wuhan nodavirus (WhNV). We here report the physicochemical characterization of WhNV and determine the nucleotide sequences of its larger segment of genome, RNA1. The results show that WhNV particles are isometric, non-enveloped, with a diameter of about 29nm. The virus has a major capsid protein and a minor capsid protein with estimated molecular mass of 40 and 44kDa, respectively. WhNV RNA1 is determined to be 3149nt long, containing a 1014-amino-acid open reading frame (ORF) encoding protein A with a calculated molecular mass of 114,608Da. The protein A shows 39 and 27% identity to its homologues in Pariacoto virus (PaV) and Striped jack necrosis nervous virus (SJNNV), respectively, but shows only 24% or less identity to its homologues in other insect Nodaviruses such as Nodamura virus (NoV), Black beetle virus (BBV), Boolarra virus (BoV) and Flock house virus (FHV). Predicted domains for six RNA-dependent RNA polymerase motifs and putative ORFs (protein B) are confirmed by sequence analysis of WhNV RNA1. [Copyright &y& Elsevier]

Fast and accurate prediction of ambient ozone (O 3) formed from atmospheric photochemical processes is crucial for designing effective O 3 pollution control strategies in the context of climate change. The chemical transport model (CTM) is the fundamental tool for O 3 prediction and policy design, however, existing CTM-based approaches are computationally expensive, and resource burdens limit their usage and effectiveness in air quality management. Here we proposed a novel method (noted as DeepCTM) that using deep learning to mimic CTM simulations to improve the computational efficiency of photochemical modeling. The well-trained DeepCTM successfully reproduces CTM-simulated O 3 concentration using input features of precursor emissions, meteorological factors, and initial conditions. The advantage of the DeepCTM is its high efficiency in identifying the dominant contributors to O 3 formation and quantifying the O 3 response to variations in emissions and meteorology. The emission-meteorology-concentration linkages implied by the DeepCTM are consistent with known mechanisms of atmospheric chemistry, indicating that the DeepCTM is also scientifically reasonable. The DeepCTM application in China suggests that O 3 concentrations are strongly influenced by the initialized O 3 concentration, as well as emission and meteorological factors during daytime when O 3 is formed photochemically. The variation of meteorological factors such as short-wave radiation can also significantly modulate the O 3 chemistry. The DeepCTM developed in this study exhibits great potential for efficiently representing the complex atmospheric system and can provide policymakers with urgently needed information for designing effective control strategies to mitigate O 3 pollution. [Display omitted] • A deep learning method (DeepCTM) is proposed to mimic the O 3 simulations of CMAQ • DeepCTM shows great potentials in 7-day continual forecast of O 3 concentrations • DeepCTM exhibits high efficiency in identifying dominant contributors to O 3 formation • DeepCTM efficiently predicts O 3 response to variations in emissions and meteorology [ABSTRACT FROM AUTHOR]