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Volcanic ash interbeds in the Late Ordovician strata in South China record high-frequency volcanic activity. To assess the impact of these volcanic events on the climate and marine biological evolutionary crisis during the Late Ordovician Mass Extinction (LOME), we present high-resolution measurements of mercury (Hg) concentrations and organic carbon isotope ratios (d13Corg) in an Ordovician-Silurian sedimentary succession (Muchanggou section). The results show that high-frequency volcanic ash layers and Hg enrichments developed synchronously in the Katian graptolite P. pacificus (Lower Subzone) and T. typicus biozones and are coupled with a negative shift of ~1? in d13Corg, which reflects the perturbation of the surface carbon and mercury cycles by intense volcanic activity. Based on volcanic Hg fluxes, it is estimated that more than 1.1 × 1013 tons of CO2 were emitted by the Katian volcanic activities in South China, which interrupted the growth of the polar ice sheet and the rapid cooling of tropical oceans in the mid-Boda event. As volcanism weakened, increased weathering led to the growth of the polar ice sheet and cooling in the Hirnantian. Both regional and global biodiversity declined rapidly with the end of volcanism, which suggests that the marine ecological crisis was related to a series of disruptions in biogeochemical cycles in the post-volcanic period. [ABSTRACT FROM AUTHOR]

All current global climate models (GCMs) only utilize grid-averaged surface heat fluxes to drive the atmosphere, and thus, their subgrid horizontal variations and partitioning are absent. This can result in many simulation biases. To address this shortcoming, a novel parameterization scheme considering the subgrid variations of the sensible and latent heat fluxes to the atmosphere and the associated partitioning is developed and implemented into the National Center for Atmospheric Research (NCAR) Climate Earth System Model 1.2 (CESM1.2). The evaluations show that in addition to the improved boreal summer precipitation simulation over eastern China and the coastal areas of the Bay of Bengal, the longstanding overestimations of precipitation on the southern and eastern margins of the Tibetan Plateau (TP) in most GCMs are significantly mitigated. The improved precipitation simulation on the southern and eastern margins of the TP is from suppressed large-scale precipitation. Moisture advection for precipitation production is blocked toward the southern edge of the TP, and the intensity of the moisture transport to the eastern edge is weakened. The corrected large-scale circulation in the lower atmosphere due to the realistic simulations of the grid-scale surface radiative and heat fluxes is responsible for the change in moisture transport. In terms of global annual mean states, some improvements are obtained by the new scheme compared to the default CESM1.2 and the scheme stochastically allocating the subgrid surface heat fluxes to the atmosphere (i.e., without subgrid partitioning included). This study highlights the importance of subgrid surface energy variations and partitioning to the atmosphere in the simulation of the hydrological and energy cycles in GCMs. [ABSTRACT FROM AUTHOR]

Eucommia ulmoides is a rare tree species in China with high medicinal and gum value. Nine strains of hyphomycetous fungi were isolated from the leaf litter of E. ulmoides in Guizhou Province. Preliminary identifications based on ITS indicated that they belong to the genus Cladosporium. Morphology and phylogenetic analyses based on the internal transcribed spacer regions (ITS) of the nrDNA, the partial translation elongation factor 1-a (tef1) gene and partial of actin (act) gene confirmed that the strains represent four species, including two novel taxa, viz., Cladosporium eucommiae and C. guizhouense and two new substrate records for known species. [ABSTRACT FROM AUTHOR]

Social stratum differences lay behind the winter sports body-building activities of Chinese residents. Guided by social stratification theory this paper takes heterogeneity research as the paradigm, and carries out in-depth interviews to explore the winter sports body-building behaviors and concepts of Chinese citizens in three classes, namely, middle class (white collar), working class (blue collar), and unemployed (jobless) class. In addition, the authors explored the correlation of participation and experience of each class with economy, education, and society dimensions of snow sports culture. This paper holds that: a. Difference in economic conditions determine the level, scope, and degree of the participation of winter sports; b. The improvement of education level accelerates the socialization progress of participants, but it also increases the differentiation of individual participation and intensifies social stratification; c. The bidding and holding of Beijing Winter Olympics greatly promotes the development of winter sports in China, and forms a feature of "middle-class consumers", while the consumption of the working class and unemployed (jobless) residents is more "rational". The paradigm of social stratification and heterogeneity research helps relevant researchers to break away from the narrow perspective of finding the individual-level causality behind winter sports body-building, laying the basis for social, and sports researchers to recognize and understand the unequal social structure of winter sports participation. [ABSTRACT FROM AUTHOR]

Soil wind erosion is one of the critical drivers of land degradation in the black soil region of northeastern China. In this study, 137Cs background value and soil wind erosion rate was studied by using 137Cs nuclide tracing technique in the black soil region of northeastern China, and wind erosion characteristics such as background value and soil erosion rate over the years were clarified, which has guiding significance for soil and water conservation and agricultural sustainable development in the black soil region of northeast China. The mean area activity of the Hilltop area was 1541 Bq·m-2, which was lower than the background value of 1879.7 Bq·m-2 in the study area. At the top of the hill, soil erosion occurred to some extent. The 137Cs profile has distributional characteristics that can be divided into three categories. Most of the 137Cs area activity in Hilltop area is evenly distributed in 0-15 cm, and the 137Cs area activity below 15 cm decreased gradually until it disappeared. The spatial difference of wind erosion rate is significant in the study area, mainly between 7.17-10.13 t·hm-2a-1. The average wind erosion rate of hilltops with different tillage quality depths has little difference. The average wind erosion rate is 8.60 t·hm-2a-1, which belongs to mild erosion. However, its erosion rate is higher than the tolerable soil loss of 2 t·hm-2a-1 in the black soil region of northeast China. As a result, soil erosion control in the black soil region of northeast China still requires attention. [ABSTRACT FROM AUTHOR]

Poor soil physical properties, serious salinization and low soil nutrients are the limiting factors for crop yield in saline-sodic soil. Long-term cattle manure application is an important measure that can affect the physicochemical properties and increase the maize yield of saline-sodic soil. This experiment included five treatments according to the history of cattle manure application: a control treatment with no cattle manure (CK) and treatments with cattle manure application for 14 years (14 a), 17 years (17 a), 20 years (20 a), and 25 years (25 a). The results indicated that compared with the CK treatment, longterm cattle manure application to saline-sodic soil resulted in significant increases in soil organic matter (SOM), soil total nitrogen (TN) and available nutrients at the 0-20 cm and 20-40 cm depths (p<0.05). The soil physical properties improved significantly, and cattle manure application significantly decreased the soil bulk density (ρb) and soil density (ρd) and increased the soil total porosity (ft) and water-holding capacity (WHC). With the number of years of cattle manure application, the soil pH, electrical conductivity (EC), exchangeable sodium percentage (ESP) and sodium adsorption ratio (SAR1:5) decreased significantly, and the maize yield gradually increased over time from 8690 kg/hm² in the CK treatment to 14 690 kg/hm² in the 25a treatment. There were significant differences among all treatments (p<0.05). The results showed that long-term cattle manure application decreased the soil ρb and saline-alkaline properties, which was the main factor that affected the maize yield in the saline-sodic soil, especially for soil ρb. [ABSTRACT FROM AUTHOR]

A new species, Achalinus sheni sp. nov., from central Hunan Province is described, based on the results of molecular systematics and morphological characters according to five specimens. Our molecular phylogeny inferred from the mitochondrial CO1 gene fragment revealed that this new species is most closely related to A. yunkaiensis, but a considerable amount of genetic divergence exists between them (p-distance ranging from 5.8% to 6.4%) and much distinct genetic divergence exists compared with other known Achalinus species (p-distance ranging from 10.4% to 15.8%), supporting its validity. Morphologically, it can be distinguished from its congeners by: (1) dorsal scales strongly keeled, 23 rows throughout the body, the outmost row smooth and significantly enlarged; (2) tail relatively short, TaL/TL 0.183 ~ 0.224; (3) the suture between internasals subequal to the suture between prefrontals; (4) loreal one, subrectangular, LorH/LorL 0.53 ~ 0.57; (5) ventrals 161-170, anal entire, subcaudals 55-61, not paired; (6) the length of supraocular equal to or longer than the length of upper anterior temporal; and (7) vertebral line inconspicuous and subcaudal streak absent. Currently, 27 species of Achalinus are known in the world, amongst which 20 species are distributed in China. Moreover, a key to species of the genus Achalinus is provided in this study. [ABSTRACT FROM AUTHOR]

In this study, the fast response of East Asian summer precipitation to COVID-19–induced aerosol emission reductions is examined using the Community Earth System Model, version 2.2 (CESM2.2). The emission reductions decreased aerosol optical depth and cloud cover over northern China in June 2020. The troposphere became warmer, strengthening the land–sea thermal contrast and anomalous southerly winds. The subtropical westerly jet accelerated and shifted southward, favoring low-level convergence, upward air motions, and subsequent condensational heating over the Yangtze River basin (YRB). The feedback of condensational heating in return strengthened the convergence and ascent. The western North Pacific subtropical high was intensified, which further enhanced the moisture advection and convergence over the YRB. Both the enhanced moisture convergence and ascent increased precipitation over the YRB during June 2020. Furthermore, local and remote emission reductions show different impacts on convection and moisture transport over the YRB. The emission reductions over China caused stronger convective precipitation (1.15 vs 0.63 mm day-1 ) but weaker larger-scale precipitation (1.17 vs 2.24 mm day-1 ) than the emission reductions outside China. In addition to the emission reductions, the sea surface temperature (SST) anomalies in 2020 also play an important role in increasing precipitation over the YRB, contributing about 42.8%. The relative contribution of SST anomalies also increases under the COVID-19–induced emission scenario. [ABSTRACT FROM AUTHOR]

Five ascomycetous strains were isolated from dead branches and leaves of Salix (Salicaceae) and Osmanthus fragrans (Oleaceae), respectively. BLAST searches with ITS sequences in GenBank suggested a high degree of similarity to Botryosphaeria dothidea. To accurately identify these strains, we further analysed their morphological characteristics of asci, ascospores, all conidiophore cells and conidia. Phylogenetic relationships, based on ITS, rpb2, tef1 and tub2 gene sequences, confirmed our strains represented two novel species, which are introduced here as B. salicicola and B. osmanthuse spp. nov. [ABSTRACT FROM AUTHOR]

In this study, four new species of Phragmidium were proposed based on morphological and molecular characters. In morphology, Phragmidium rosae-roxburghii sp. nov. was distinguished to related taxa by its unique square to diamond-shaped urediniospores; Ph. rubi-coreani sp. nov. differed from Ph. barclayi and Ph. cibanum because of teliospores with fewer cells and shorter pedicels; urediniospores of Ph. potentillaefreynianae sp. nov. were bigger than Ph. duchesneae-indica; and Ph. rosae-laevigatae sp. nov. produced bigger urediniospores than Ph. jiangxiense. The phylogenetic analyses based on the combination of two loci (ITS and LSU) also supported our morphological conclusion. In the meantime, three previously known species were also described herein. [ABSTRACT FROM AUTHOR]

The surface evapotranspiration (ET) process is the key link in the interaction between land and atmosphere. However, the influence of different environmental factors on ET over transitional climate zones and the physical pattern of the interaction between multiple factors remain unclear. Therefore, based on the continuous observation data during the vegetation growing season of a typical grassland in the Semi-Arid Climate and Environment Observation of Lanzhou University (SACOL) station from 2007 to 2012, the influence pattern of multiple environmental factors on ET over China's transitional climate zone was analysed. Each environmental factor exhibited significant seasonal and interannual variations. The mean value of ET was 1.67 mm day-1. Although the maximum values of sensible heat flux and vapour pressure deficit occurred in April and June, respectively, the maximum values of other environmental factors appeared from July to August. Net radiation, soil moisture, and normalized difference vegetation index (NDVI) were the main controlling factors of ET over the grassland, with correlation coefficients of 0.54, 0.52, and 0.46, respectively. The analysis of multiple environmental factors showed that when soil moisture, wind speed, net radiation, and NDVI reached 0.2 m³ m-3, 2 m s-1, 100 W m-2, and 0.2, respectively, ET varied in contrast with vapour pressure, vapour pressure deficit, and air temperature under the influences of weather processes, land–atmosphere coupling, and drought stress. These findings deepen our understanding of the role of ET in the land–atmosphere coupling process over the transitional climate zone in China. [ABSTRACT FROM AUTHOR]

A new species of Leaf Litter Toad, Leptobrachella shimentaina sp. nov., is described from the Shimentai and Luokeng nature reserves of northern Guangdong Province, southern China. The new taxon can be distinguished from all recognized congeners by a combination of discrete morphological character state differences relating to its small body size (SVL 26.4--28.9 mm in six adult males, 30.1 and 30.7 mm in two adult females); a number of apparently fixed color pattern character differences (including eye coloration and color pattern features from dorsal, ventral, and dorsolateral surfaces of its head, body, limbs, and ventrum); the morphological and discrete characteristics of the external phenotype (the skin texture of dorsum and ventrum, the presence of supra-axillary and ventrolateral glands, the wide dermal fringes and rudimentary webbing on toes, and the uninterrupted longitudinal ridges under toes). Two samples of this new species previously were proposed as representing a new, unnamed species. We now substantiate this claim by providing diagnostic comparisons of discrete character differences. In addition, we also discuss taxonomic uncertainty surrounding the identity of two congeners, L. chishuiensis and L. purpurus, which we interpret as indicative of taxonomic inflation in the species-rich subfamily Megophryidae. [ABSTRACT FROM AUTHOR]

Nidirana guangxiensis sp. nov., a new music frog species, is proposed, based on a series of specimens collected from Mt Daming, Guangxi, southern China. The new species is close to N. yeae, N. daunchina, N. yaoica, and N. chapaensis from southwestern and south-central China and northern Indochina, while the relationships among these species remain unresolved. Nidirana guangxiensis sp. nov. can be distinguished from all known congeners by the genetic divergences in the mitochondrial 16S and COI genes, the behavior of nest construction, the advertisement call containing 6-11 rapidly repeated regular notes, and a combination of morphological characteristics. Furthermore, the Nidirana populations recorded in Guangxi are clarified in this work, providing valuable new information on the knowledge of the genus Nidirana. [ABSTRACT FROM AUTHOR]