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Table of Content

    20 May 2020, Volume 56 Issue 3
    Analysis of Aerodynamic Noise Characteristics of Pantograph in High Speed Train
    YAO Yongfang, SUN Zhenxu, LIU Wen, YANG Guowei
    2020, 56(3):  385-398.  DOI: 10.13209/j.0479-8023.2020.014
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    The delayed detached eddy simulation (DDES) coupled with the acoustic finite element method (FEM) is applied to analyze aerodynamic noise characteristics of a high-speed train with a pantograph. Numerical results are presented in terms of spectrum characteristics and distributions of aerodynamic noise in near and far fields in the case of pantograph with demo in up and down situations. The influence of different modeling methods on the flow field of the pantograph is considered, and the effects of scattering and reflection of sound waves from the body and shroud panels on aerodynamic noise results are also took into account. The following interesting phenomena are drawn. 1) Under the pantograph shape and selected opening direction, the noise induced by downpantograph with dome is higher than that induced by up-pantograph with dome. 2) The noise induced by the dome has a large proportion of noise in the low frequency region below 300 Hz, while the noise induced by the pantograph has a greater influence after 300 Hz. Using the dome as the sound source face, the noise is larger in the case of up-pantograph. 3) About the directivity of the induced noise, in the horizontal plane, the front of the pantograph, the dome contributes more to the noise, and in the rear of the pantograph, the pantograph contributes more. In the upper part of the train, the noise induced by the pantograph itself is greater than the noise induced by the dome, becoming the main source of aerodynamic noise in this case.
    Synthesis of Oxalate Peroxo-uranyl Complex in situ by Photoreaction
    WEI Wenqi, LIU Chunli
    2020, 56(3):  399-405.  DOI: 10.13209/j.0479-8023.2020.016
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    [NH3(CH2)2NH3]3[(UO2)2O2(C2O4)4]·4H2O (1), [NH3(CH2)2NH2(CH2)2NH3]2[(UO2)2O2(C2O4)4]·2H2O (2) and [NH3(CH2)2NH2(CH2)2NH3]2[(UO2)2O2(C2O4)4] (3) were synthesized in situ under room temperature and laboratory lamp condition, using 1,2-diaminoethane and 2,2'-diaminodiethylamine separately as templates. Structures and properties were characterized by single-crystal X-ray diffraction, Raman spectra, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The dihedral angle of U-O2-U in 1 and 2 is 180°, which deviates from the natural angle of peroxide. The peroxide bond length of 2 and 3 is shorter than that of the reported peroxide, and the bond lenth of 2 is close to superoxide bond length. However, both valence and Raman spectra indicated that 2 and 3 are peroxide bonds.
    Microseismic Monitoring Events Classification Based on Waveform Clustering Analysis and Application
    ZHAI Shang, YU Zhichao, TAN Yuyang, HUANG Fangfei, LIU Ling, HU Tianyue, HE Chuan
    2020, 56(3):  406-416.  DOI: 10.13209/j.0479-8023.2020.018
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    Based on the difference of waveform similarity between different types of microseismic monitoring events and combined with their characteristics in occurrence location, traveling time and polarization direction etc., a method for classifying microseismic monitoring events based on waveform clustering analysis is proposed. Firstly unclassified events can be identified rapidly using conventional microseismic event detection methods, then similar events are grouped based on waveform clustering analysis, finally the types of microseismic events or noise events are determined combining the attribute characteristics. Classified microseismic events can be further used for template matching technique to finely detect similar events with low signal-to-noise ratio. Meanwhile the global optimization approach which aims to improve the accuracy of arrival time picking can be also performed by taking similar microseismic events as a whole. 
    Impacts of Temporal Resolution and Spatial Information on Neural-Network-Based PM2.5 Prediction Model
    ZOU Silin, REN Xiaochen, WANG Chenggong, WEI Jun
    2020, 56(3):  417-426.  DOI: 10.13209/j.0479-8023.2020.012
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    Taking Beijing as an example and using the data of air quality monitoring stations from 2015 to 2018, the impacts of temporal resolution and spatial information on the PM2.5 concentration prediction were analyzed by a BP neural network, an LSTM network, and a CNN-LSTM hybrid model. The results show that neural network models are generally better than the multi-linear regression model. Increasing the temporal resolution of the input data can significantly improve the accuracy of the predicted daily average PM2.5 concentration. When the temporal resolution of the input data increases from one day to 6 hours, the mean absolute error of the LSTM model reduces from 27.39 μg/m3 to 20.59 μg/m3. This improvement is more obvious when the weather is significantly getting better or getting worse. The distribution of PM2.5 concentration in North China has distinct spatial and temporal characteristics. The first spatial mode is a uniformly increasing or decreasing mode, and the second one is a north/south dipole mode. The analysis shows that the concentration of PM2.5 in Beijing is related to the PM2.5 in Inner Mongolia, Hebei, and Tianjin of the previous day. The CNN-LSTM hybrid model, trained with the spatialtemporal information of PM2.5 in North China, can further improve the predictability of PM2.5 in Beijing. It further reduces the mean absolute error to 17.36 μg/m3.
    Application Research of Active Source Rayleigh Wave Multi-Mode Extraction Method Based on Vector Wavenumber Transformation Method in Near Surface Stratigraphic Structure Detection
    SU Yue, YANG Zhentao, YANG Bo, ZHAO Liang
    2020, 56(3):  427-435.  DOI: 10.13209/j.0479-8023.2020.021
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    Based on the array of the transient multi-channel analysis of surface waves (MASW), Rayleigh wave dispersion imaging methods including vector wavenumber transformation method (VWTM), phase shift, and highresolution linear Radon transform are used to carry out comparative analysis. First, the dispersion imaging results of synthetic data are compared to analyze the quality of the three methods. The VWTM is found superior to the other two in terms of resolution, accuracy of higher modes, fitting degree with theoretical dispersion curves and anti-noise property. In the actual Rayleigh wave detection, the VWTM can still has advantages in foundamental mode imaging accuracy and higher order modes imaging quality. Then the genetic algorithm is employed to invert the dispersion curves of fundamental mode and higher modes. The result is more accurate and stable when higher modes are combined in the inversion, it also performs much better in reducing non-uniqueness of inversion. The research shows that the VWTM can extract multi-mode characteristics of Rayleigh wave dispersion effectively and with high quality in field prospecting, which provides a reliable data foundation for joint inversion of multi-mode of Rayleigh wave dispersion curves. In conclusion, the VWTM combined with effective inversion method can remarkably improve the accuracy of near surface stratigraphic structure detection and has great potential in enhancing Rayleigh wave exploration capability.
    Zircon U-Pb-Lu-Hf Isotopic Characteristics and Geological Implications of Mesozoic Granites in Western Qinling
    LIU Wei, GUO Lishuang, LIAO Yanfu, ZHAO Yonghong, LIU Yulin, XIAO Yanjun
    2020, 56(3):  436-448.  DOI: 10.13209/j.0479-8023.2020.028
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    LA-ICP-MS zircon U-Pb isotopic analyses reveal that the granitoid intrusions of Zhongchuan, Baijiazhuang and Jiaochangba in Western Qinling orogeny emplaced at ages of 220±1, 216±6 and 222±6 Ma, respectively, showing that all of them belongs to Middle-Late Triassic granitoid magmatism. Whole rock geochemistry analyses indicate that the primitive mantle-normalized trace element patterns and Chondrite-normalized REE patterns of the rock samples from the three intrusions show significant similarity, for example, depletion in high field strength elements of Nb, Ti and P, and enrichment in LREE. Analyses for zircon Lu-Hf isotopes indicate that the εHf(t) values range from ?3.31 to +1.68 of the three intrusions with the two-stage model ages between 1151 and 1456 Ma. Petrogenetic studies indicate that the granitoid magmas of these Indosinian granitoid intrusions were derived mainly from the partial melting of mesoproterozoic crust material. Combined with the formation age, petrogenesis and tectonic background, these Indosinian intrusions were most likely formed in the collision process between South Qinling orogen and South China Block along Mianlue suture zone, and might be related to the subducted slab break off of South China Block.
    Analysis of Characteristics of Tight Sandstone Reservoir with Porous-Fissure Dual Medium in Toutunhe Formation of Sikeshu Sag
    YUAN Bo, DONG Xuemei, GUAN Xutong, ZHOU Tianqi, WANG Xinqiang, WEI Lingyun, ZHAO Jinyong, FENG Geng, WU Chaodong
    2020, 56(3):  449-459.  DOI: 10.13209/j.0479-8023.2020.011
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    Synthesizing core, outcrop, drilling data, the sedimentary environment was reconstructed. The petrography analysis, reservoir space category summary, diagenesis recovery and controlling factors of the reservoir analysis were conducted. The tight sandstone reservoir with dual medium in Toutunhe formation fractures of Sikeshu sag has the characteristics of “three low one weak” of low component maturity, low shale content and lower cement content. The pore type is mainly composed of remaining intergranular pores and a few intragranular pores and fissure types mainly consist of bedding fissures and diagenetic fissure. The principal elements controlling the tight sandstone reservoir property of in Toutunhe formation fractures of Sikeshu sag are depositional environment, burial process, compaction and tectonism. The tight sandstone reservoir with braided river delta front subfacies that developed in the Gaoquan anticline and West Lake anticline has favorable prospect for exploration. The coarse sandstones with a small amount of plastic grain content possesses better reservoir quality. The reservoir is mainly controlled by compaction. Denudation pore increasing and cementation hole reduction is limited. Fissures improve reservoir properties effectively.
    A Study of Pollutant Loads Variations in Shenzhen River Estuary in Recent Decade
    YU Yi, SONG Fang, ZHAO Zhijie, QIN Huapeng, DUAN Yujie, YAO Lijuan, WANG Zhengjun
    2020, 56(3):  460-470.  DOI: 10.13209/j.0479-8023.2020.015
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    This study applies a LOADEST model to hydrology and water quality data from 2008 to 2017 to examine the variation of pollutant loads in Shenzhen River estuary. These investigated pollutants include COD, NH3-N, TN and TP. The result from the LOADEST model, alone with situation of both precipitation and wastewater treatment plants, are used to analyze both natural and artificial impacts on the pollutants. The research concludes the following statements. 1) The net pollutant loads in Shenzhen River decreased significantly from 2008 to 2017, but still not enough to reach level V for river water quality standard (GB3838–2002). 2) The seasonal variations of net pollutant loads reduced from 2008 to 2017. 3) There is a strong correlation between precipitation and COD net load, which indicates that this pollutant is mainly originated from non-point sources. Precipitation and NH3-N, TN and TP net loads have weak correlations, which means that point sources are the main contributors of these pollutants. 4) There is a negative correlation between net pollutant loads and the amount of treated wastewater. This illustrates the enhanced capacity of waste water treatment plants, as well as the improved quality of discharged treated water will contribute to better water quality in Shenzhen River.
    Effects of Grazing Exclusion on the Vegetation Community Composition and the Community Stability of Dry Steppe and Mountain Steppe Ecosystems in Mongolia
    LIAO Hanru, Indree Tuvshintogtokh, GUO Tong, ZHAO Jingxue
    2020, 56(3):  471-478.  DOI: 10.13209/j.0479-8023.2020.017
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    Two types of typical steppe ecosystems in Mongolia (dry steppe and mountain steppe) with two treatments (enclosure and grazing) were studied to analyze the vegetation cover from 2013 to 2018. The plant species of the community were divided into five functional groups: forbs, artemisia, legumes, grasses and sedges. The Gordon stability index was used to evaluate the effect of enclosure on the community stability. Here are the results. 1) Enclosure significantly increased the coverage of forbs in the dry steppe, while reduced the coverage of artemisia and gramineous groups. The effects had no obvious variations among years. For the mountain steppe, enclosure slightly affected the coverage of different functional groups. 2) Enclosure increased the stability of the dry steppe while little influenced the stability of the mountain steppe. 3) The Gordon stability index had a significantly positive relation with the cover ratio of dominant species to the communities. The ratio in the dry steppe was higher than that in the mountain steppe, leading to a higher community stability of the dry steppe. Before the enclosure management in grasslands, we should fully consider local environmental conditions and the potential impact of enclosure on the plant community and the ecosystem. At the same time, grazing rest, rotational grazing, seasonal grazing and other measures should be supplemented to improve the use value of grassland ecosystem services.
    Landscape Pattern Characteristics of Land Use along the Wide Reaches of the Lower Yellow River
    CHENG Shupeng, SUN Yuhang, JIANG Hanlin, ZHAO Zhijie, LI Zhenshan, XUE An
    2020, 56(3):  479-490.  DOI: 10.13209/j.0479-8023.2020.022
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    Based on the 15 m×15 m spatial distribution raster data of 11 types of land use in 2015 and the landscape pattern index, the landscape pattern characteristics of land use in the counties, floodplains and flood detention areas along the wide reaches of the Lower Yellow River, and gradient characteristics of the landscape patterns of land use in the 18 2km-buffer zones on both sides, are compared and analyzed. The results show that the dry farmland is the dominant landscape within the counties along the wide reaches, followed by the rural residential land, and they account for more than 80% of the total area of the counties. The paddy fields and the other categories of waters have a certain scale and the scale of the grassland is small. Influenced by factors such as functional orientation and natural conditions, there are obvious spatial differences in land use landscape patterns in the counties, floodplains and flood detention areas along the wide reaches of the Lower Yellow River. There are large-scale and densely-distributed construction land in the extra-floodplains area of the counties, the landscape fragmentation of which is high and the patch shape is complex. The landscape diversity of the Dongping Lake flood detention area is high, showing a complex ecological landscape with waters as the main body, and in the other two flood detention areas, the scale of woodland and grassland is small, the patch density and the landscape heterogeneity is low. The overall landscape fragmentation in the wide reaches’ floodplains is lower than that in the extra-floodplains area, the landscape diversity of the wandering reaches’ floodplains is relatively high, and the construction land is relatively large. Within 6 km of the two sides of the wide reaches, the paddy fields and the other categories of waters are large in scale and densely distributed, the scale of the urban land is small, and the overall landscape diversity in this region is high and relatively fragmented; the transition region is from about 6 km to 18 km; the landscape patterns tends to be stable over 20 km away.
    Impacts of Field Management Measures and Soil Erosion on Greenhouse Gases Fluxes of the Farmland
    CHEN Jinfeng, YUE Yao
    2020, 56(3):  491-499.  DOI: 10.13209/j.0479-8023.2020.023
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    In order to explore the impact of field management measures and soil erosion on greenhouse gases (GHGs) fluxes, the Yucheng Experimental Station of the Chinese Academy of Sciences was selected as the research area. By collecting data of meteorology, soil and field management measures, we estimated CO2 and N2O fluxes under different intensities of nitrogen application, fertilization depths, and soil erosion rate, using DNDC model. Compared with observed data, DNDC model performed well in simulating CO2 and N2O fluxes. As the intensity of nitrogen application increased, the N2O flux also increased linearly from 1.06 mg/(m2·d) to 2.88 mg/(m2·d). The NEE also gradually increased from 1.38 g/(m2·d) to 2.07 g/(m2·d), but the increasing trend gradually slowed down. With the fertilization depth changing from 5 cm to 20 cm, the N2O flux decreased from 2.88 mg/(m2·d) to 0.68 mg/(m2·d). Moreover, when the fertilization depth increased from 0.2 cm to 20 cm, the NEE gradually increased from 1.79 g/(m2·d) to 2.32 g/(m2·d), but the increasing trend also slowed down. Under the impact of soil erosion, the NEE and the N2O flux increased by 11% and 4%, respectively. This study helps to complete the national inventories of GHGs emission, and provides basis for the policy-making of GHGs management in farmland.
    Diversity of Antibiotic Resistance Genes in Water Source Areas of the Middle Route of the South-to-North Water Transfer Project
    PAN Rui, LIU Shufeng, WANG Jiawen, NI Jinren
    2020, 56(3):  500-508.  DOI: 10.13209/j.0479-8023.2020.024
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    In order to study the pollution status and regularity of antibiotic resistance genes (ARGs), highthroughput sequencing methods were used to analyze the diversity of ARGs along Danjiangkou Reservoir and Hanjiang River in spring and autumn of 2014. 21 and 19 types of ARGs were detected in spring and autumn samples respectively. Among them, 9 types of ARGs were the main types of ARGs content. Bacitracin was the most important ARGs in water, while β-lactam accounted for the highest proportion in the Taocha sampling sites of Danjiangkou Reservoir. The composition difference of ARGs among sampling sites in Water_Autumn samples was smaller than that in spring. NMDS and ANOSIM analysis showed significant seasonal differences in the composition of ARGs. Trimethoprim, polymyxin and multidrug were ARGs which had significant seasonal differences. Correlation analysis found 13 types of ARGs with significantly strong correlations with each other, and the most relevant ARGs were likely to coexist in the same microorganism. In addition, tetracycline and aminoglycoside may be useful as indicators for predicting the relative abundance of ARGs coexisting in the water source region. This study could provide reference for water quality protection and ARGs pollution prevention and management in drinking water source areas.
    Community Characteristics of Dominant Archaea before and after the Danjiangkou Dam
    LIN Yaxuan, DANG Chenyuan, ZHONG Sining, WANG Jiawen, ZHENG Tong, NI Jinren
    2020, 56(3):  509-517.  DOI: 10.13209/j.0479-8023.2020.034
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    The 16S rRNA Illumina Miseq high-throughput sequencing technology was used to analyze the species composition of archaea in the Danjiangkou reservoir area and the downstream Hanjiang River. The structure of ammonia-oxidizing archaea (AOA) and methanogenic archaea that dominated the water and sediments in the upstream and downstream dam was analyzed. The results showed that the structure of the dominant species was affected by the samples difference, which could be explained by the aerobic preference of the ammonia-oxidizing archaea and the anaerobic properties of the methanogenic archaea. According to the network analysis, there was a significant correlation between the ammonia-oxidizing archaea and the methanogenic archaea in the upstream of the Danjiangkou reservoir. Because of the operation of the Danjiangkou reservoir, the abundance of ammoniaoxidizing archaea in the water and sediments of downstream of the dam was reduced, and the abundance of methanogenic archaea in the sediments was relatively high. The relation between them was not obvious.
    Using Mobile Phone Data to Estimate the Temporal-Spatial Distribution and Socioeconomic Attributes of Population in Megacities: A Case Study of Beijing
    HAI Xiaodong, LIU Yunshu, ZHAO Pengjun, ZHANG Hui
    2020, 56(3):  518-530.  DOI: 10.13209/j.0479-8023.2020.035
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    This study proposes a technique to identify the temporal-spatial distribution and socioeconomic attributes of population by using mobile phone data. This technique has a fine geographic scale, which is called as Spatial Pattern Unit. The study uses Beijing as a case and conducts an empirical application of the technique. Firstly, it investigates the temporal-spatial distribution of population in Beijing by using multiple data sources, including mobile phone data, travel survey data and heat map data. Secondly, it classifies the spatial pattern unit into different categories in terms of socioeconomic attributes of population and travel behavior features. Thirdly, it applies machine learning approach to estimate socioeconomic attributes of population for all spatial pattern units. Finally, it compares and verifies the results of analysis. The approaches and findings would be valuable to monitoring population distribution, locating business services and planning urban infrastructure.
    Indicative Significance of Tree Tracheid Size on Forest Growth and Environmental Adaptability in the Forest-Grass Ecotone of Southern Siberia
    XUE Jiaxin, LIU Hongyan, XU Chongyang, Oleg A. Anenkhonov, Denis V. Sandanov, Andrey Yu. Korolyuk, JIANG Zihan, LIU Xu, Larisa D. Balsanova, Bulat B. Naidanov
    2020, 56(3):  531-538.  DOI: 10.13209/j.0479-8023.2020.027
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    In order to study the relationship of three growth features of cell, tree and forest that indicate adaptation of trees to water deficit, we measured the tree-ring widths of 725 tree-cores sampled from sites dominated by Larix sibirica and Pinus sylvestris and then 195 of them were randomly selected to measure the tracheid size. The results show that the tracheid size is significantly correlated to the radial growth and the inter-annual variation in ring width, at both levels of the tree individual and forest community, regardless of local environment and tree species. This result suggests that small mean tracheid cells indicate low growth rate and more growth variation. The study implies that the mean tracheid size could serve as a robust indicator of tree or forest adaptation to habitat humidity for conifers in the semi-arid region and reveals the trade-off between growth adaptation and growth safety of trees by regulating tracheid size. As an important xylem trait of conifer forests, the size of tracheid is valuable for the further physiological study of drought adaptation of trees in the semi-arid region.
    Coupling Process and Decoupling Analysis of Agricultural Development and Resource-environment in Beijing
    LIU Yu, TANG Linnan, PAN Yuchun
    2020, 56(3):  539-545.  DOI: 10.13209/j.0479-8023.2020.013
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    Based on the perspective of sustainable agricultural development, this study systematically discusses the spatial-temporal evolution characteristics, coupling and decoupling process of agricultural development and resource-environment in Beijing since 2005. The results are as follows. 1) From 2005 to 2017, Beijing’s agricultural development first strengthens and then weakens. The development characteristics of economic output are similar to those of agricultural development; the indexes of agricultural social development first decreases rapidly and then slowly increases, but generally showing a weakening trend; the industrial modernization continues to improve. 2) The pressure of agricultural resources and environment strengthens first and then abates. The change trend of the resource carrying and consumption indexes are the same as that of the pressure index, and the influence on the pressure index of agricultural resources and environment is obvious; the environmental pollution index decreases year by year. 3) There has been a dynamic evolution from “the most unfavorable state→the ideal state→the relatively optimistic state” between the pressure of resources and environment and the development of agriculture in the city, with coexistence of decoupling and coupling states and the decoupling state as the main one. In the process of agricultural sustainable transformation and upgrading in future, it is necessary to emphasize the ecological development of agriculture and its multi-functional value excavation and to promote its orderly balance with resources and environment.
    Preparation of Magnetic g-C3N4-Fe3O4 Nanocomposites and the Photocatalytic Degradation of Three Quinolones in Aqueous Solution
    TAO Huchun, LIANG Hongfei, ZHANG Lijuan, DING Lingyun, ZHANG Shanfa, ZHU Lili, DENG Liping
    2020, 56(3):  546-552.  DOI: 10.13209/j.0479-8023.2020.026
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    Magnetic g-C3N4-Fe3O4 nanomaterials were prepared by using melamine and iron salts as raw materials, and the effects of different operating factors on the photocatalytic degradation of three quinolone antibiotics were investigated. The optimal conditions for the photocatalytic reactions were: initial antibiotic concentration of 3.0 mg/L, initial g-C3N4-Fe3O4 dose of 0.60 g/L, at 25℃, and pH=7. Under optimized conditions, the degradation efficiencies of Lomefloxacin, Ofloxacin and Ciprofloxacin were 83.6%, 60.9% and 99.0% after 100 min light irradiation, respectively. XRD and UV-vis analyses show that the graphite-phase g-C3N4 has strong interaction with magnetic Fe3O4, resulting in the formation of more photogenerated electron-hole pairs and enhancing the photocatalytic activity of the composite nanomaterials. After repeated recycling for 5 times, there are more than 90% of magnetic g-C3N4-Fe3O4 nanomaterials recovered, and the photocatalytic efficiency is maintained at higher than 60%.
    Classification of County Natural Landscape Governance Units for Wusheng
    WANG Zhifang, ZHOU Yaojin, XU Min, FU Hongpeng, WANG Sirui
    2020, 56(3):  553-560.  DOI: 10.13209/j.0479-8023.2019.080
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    Ecological regionalization research in China were focused on large scales and based on natural conditions, which is unable to provide practical suggestions for rural development. In this study, the classification of natural landscape governance unit framework was proposed in Wusheng County with cluster analysis, which may serve as the basis in planning. Three variables were considered in the analysis—30 m elevation, slope and land use, which were used in a Two Step Cluster analysis to define landscape types. According to results, Wusheng County can be divided into seven kinds of landscape governance units. The internal geographic features of the unit are similar, and the differences between the groups are significant. Three different governance modes can be defined: single town, single village and complex village. Analyzing the causes and proposing governance strategies is necessary for complex villages. The development strategy of the seven built-up areas of Wusheng are proposed.
    A Case Study on the Relationship Between Urbanization Level and Water Use Efficiency in the Pearl River Delta Urban Agglomeration
    ZENG Hui, YAN Chunhua, HUANG Wanbin, LIN Qianyun, YU Leiyu, QIU Guoyu
    2020, 56(3):  561-570.  DOI: 10.13209/j.0479-8023.2020.032
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     This study evaluates comprehensive urban development level based on the data of population change, economic optimization, social development, and water use between 2005 and 2017 in the Pearl River Delta Urban. Then an improved water footprint calculation method is used to analyze water use efficiency and urbanization level, whose relationship is quantified and verified. The study found that: 1) regarding urbanization level, the Pearl River Delta Urban Agglomeration can be divided into four grades, of which Guangzhou and Shenzhen are at a high level; 2) using water footprint calculation method, the total of the agglomeration in 2016 is 58.58 billion m3, which is significantly higher than the claimed 28.99 billion m3 in <2016 Guangdong Water Resources Bulletin>; 3) at different urbanization stages, the trend of the total water footprint varies, each showing a unique characteristics; 4) with a continuous urbanization, water use efficiency will continue to increase.
    Effect of Perceived Social Support on the Efficacy of Online Cognitive Behavioral Therapy for Social Anxiety Disorder
    WEN Xu, ZHAO Chenying, Kishimoto Tomoko, QIAN Mingyi
    2020, 56(3):  571-578.  DOI: 10.13209/j.0479-8023.2020.025
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    This study aims to investigate the relationships among perceived social support, objective social support and social anxiety, and the efficacy of perceived social support in Internet-based Cognitive Behavioral Therapy (ICBT). In study 1: 122 undergraduates was investigated in their social support and social anxiety at two time points between 2 months. The results indicated that there was a significant positive correlation between objective social support and perceived social support. The mediating effect of perceived social support was significant between objective social support and social anxiety, 95% confidence interval [–1.47, –0.09]. Study 2: 64 participants in different levels of perceived social support was assigned to ICBT with social support groups or non-social support groups. The results suggested that ICBT reduced participants’ social anxiety in both social support groups. Moreover, the level of perceived social support in social support groups significantly increased than that of non-social support groups, and the perceived social support level in both groups enhanced after intervention. The perceived social support interacted with the effect of ICBT with social support groups. For participants with low perceived social support, ICBT with social support groups exhibited the better intervention. For participants with high perceived social support, ICBT without social support groups exhibited the better intervention. The study further understands and clarifies the role of social support in social anxiety and provides a foundation and direction for future clinical practice and application.