Heavy metal concentrations of agricultural soils and vegetables from Dongguan, Guangdong

A total of 118 of agricultural soil and 43 of vegetable samples were collected from Dongguan City, Guangdong, China. The spatial distribution, sources, accumulation characteristics and potential risk of heavy metals in the agricultural soils and vegetables were depicted in details by three different approaches, including total contents of eight metal elements in soils and vegetables, GIS maps and multivariate analysis of heavy metals in soils in the study. The results show that there are higher accumulation of heavy metals such as Cu, Zn, Ni, Pb, Cd and Hg in agricultural soils, and the contents of Pb （65.38 mg kg^-1） and Hg （0.24 mg kg^-1） are 1.82 and 2.82 times of the background contents of the corresponding heavy metals in soils of Guangdong Province, respectively. There are about 3.4% of Cu, 5.9% of Ni, 1.7% of Cd and 28% of Hg in all collected soil samples from all investigated sites which have overran the contents for heavy metals of the China Environmental Quality Standard for Soils （GB15618-1995, Grade Ⅱ）. The pollution characteristics of multi-metals in soils are mainly reflected by Hg. There are different sources to eight metal elements in soils, Cu, Zn, Ni Cr and As are predominantly derived from parent materials, and Pb, Hg and Cd are affected by anthropogenic activities. The spatial distribution shows that the Cu, Zn, Ni, Cr, Pb, As and Hg contents of agricultural soils are high in the west and low in the east, and Cd contents are high in the northwest, southeast and low in the southwest in Dongguan. The ratios of vegetable samples which Ni, Pb and As concentrations higher than the Maximum Levels of Contaminants in Foods （GB2762-2005） are 4.7%, 16.3% and 48.8%, respectively. The order of bio-concentration factors （BCF） of heavy metals in vegetables is Cd 〉 Zn 〉 Cu 〉 As 〉 Ni 〉 Hg 〉 Cr 〉 Pb. It is necessary to focus on potential risk of heavy metals for food safety and human＇s health from agricultural soils and vegetables in Dongguan City, Guangdong Province.

CHARACTERISTICS OF BOUNDARY LAYER AND ITS EFFECTS ON ATMOSPHERIC AEROSOL CONCENTRATIONS IN DONGGUAN, GUANGDONG

The structure of atmospheric boundary layer determines the ability of atmospheric dispersion and has an essential impact on airborne aerosols.In this paper,the data of a radio sounding experiment held in Dongguan National Meteorological Observation Station,which is in a coastal city in Pearl River Delta,as well as the data of atmospheric aerosols,were utilized in order to analyze the characteristics of atmospheric boundary layer and its effects on surface aerosol concentrations.The results are showed at follows:the local circulations,associated with dominant winds,made complex structures of atmospheric layers,as the cold air and systematic winds weakened in the end of a cold air event.Weakened wind shears and inversion layers,especially a strong near-surface inversion layer,remarkably diminished the atmospheric diffusion abilities and facilitated an especially high concentration of surface aerosols.The convergence line or weak shear line of sea breeze in the ground level helps weaken the atmospheric diffusion abilities and results in atmospheric aerosols accumulation.

A potential giant gallium deposit hosted in the tailing dam of the Fankou Zn-Pb deposit in northern Guangdong Province, South China

1.Objective The Fankou giant zinc(Zn)-lead(Pb)deposit in Guangdong Province is well-known for its huge reserves of over 10 Mt(million ton)Zn+Pb metals and high ore-grade with Zn+Pb exceeding 15%(Guangdong Fankou Deposit Investigation Group,1980;Zhu XY et al.,2017).After 60 years of exploration and exploitation,the deposit has accumulated millions of tons of tailings.One interesting question is that what components are hosted in these tailings,and whether some key and critical metals such as gallium and germanium are extremely enriched and worth further comprehensive utilization.This motivated us to conduct an integrated set of field investigation,sampling,major-trace element analyses and reserve assessments about the Fankou tailings.In this contribution,we discover that the tailings contain a variety of metal elements such as zinc,lead and gallium with comprehensive utilization potential.These data can act as a scientific guidance for further exploration and utilization of the Fankou tailings,and aid to enhance the utilization efficiency of the key mineral resource in China.Our study also provide demonstration for future green mine construction in China.

Scale effect of coastal landscape pattern stability and driving forces:a case study of Guangdong Province,China

The long-term dynamic evolution and underlying mechanisms of coastal landscape pattern stability,driven by strong anthropogenic interference and consequently climate change,are topics of major interest in national and international scientific research.Guangdong Province,located in southeastern China,has been undergoing rapid urbanization over several decades.In this study,we quantitatively determined the scale threshold characteristics of coastal landscape pattern stability in Guangdong Province,from the dual perspective of spatial heterogeneity and spatial autocorrelation.An analysis of the spatiotemporal evolution of the coastal landscape was conducted after the optical scale was determined.Then,we applied the geodetector statistical method to quantitatively explore the mechanisms underlying coastal landscape pattern stability.Based on the inflection point of landscape metrics and the maximum value of the MoranⅠindex,the optimal scale for analyzing coastal landscape pattern stability in Guangdong Province was 240 m×240 m.Within the past several decades,coastal landscape pattern stability increased slightly and then decreased,with a turning point around 2005.The most significant variations in coastal landscape pattern stability were observed in the transition zone of rural-urban expansion.A q-statistics analysis showed that the explanatory power of paired factors was greater than that of a single driving factor;the paired factors with the greatest impact on coastal landscape pattern stability in Guangdong Province were the change in gross industrial output and change in average annual precipitation from 2010 to 2015,based on a q value of 0.604.These results will contribute to future efforts to achieve sustainable coastal development and provide a scientific basis and technical support for the rational planning and utilization of resources in large estuarine areas,including marine disaster prevention and seawall ecological restoration.

Mechanism of Guangdong Shenqu in regulating intestinal flora in mice with food stagnation and internal heat based on 16S rDNA sequencing

Objective:To investigate the effect of Guangdong Shenqu(GSQ)on intestinal flora structure in mice with food stagnation through 16S rDNA sequencing.Methods: Mice were randomly assigned to control,model,GSQ low-dose(GSQL),GSQ medium-dose(GSQM),GSQ high-dose(GSQH),and lacidophilin tablets(LAB)groups,with each group containing 10 mice.A food stagnation and internal heat mouse model was established through intragastric administration of a mixture of beeswax and olive oil(1:15).The control group was administered normal saline,and the model group was administered beeswax and olive oil to maintain a state.The GSQL(2 g/kg),GSQM(4 g/kg),GSQH(8 g/kg),and LAB groups(0.625 g/kg)were administered corresponding drugs for 5 d.After administration,16S rDNA sequencing was performed to assess gut microbiota in mouse fecal samples.Results: The model group exhibited significant intestinal flora changes.Following GSQ administration,the abundance and diversity index of the intestinal flora increased significantly,the number of bacterial species was regulated,andαandβdiversity were improved.GSQ administration increased the abundance of probiotics,including Clostridia,Lachnospirales,and Lactobacillus,whereas the abundance of conditional pathogenic bacteria,such as Allobaculum,Erysipelotrichaceae,and Bacteroides decreased.Functional prediction analysis indicated that the pathogenesis of food stagnation and GSQ intervention were primarily associated with carbohydrate,lipid,and amino acid metabolism,among other metabolic pathways.Conclusion: The digestive mechanism of GSQ may be attributed to its role in restoring diversity and abundance within the intestinal flora,thereby improving the composition and structure of the intestinal flora in mice and subsequently influencing the regulation of metabolic pathways.

Zhongshan:Rising Dragon of Guangdong

My journey to Zhongshan City in Guangdong Province alongside experts,foreign correspondents,and local Chinese journalists proved to be an enlightening exploration of the intricacies of China’s development,especially within its smaller cities.While a brief five-day sojourn wasn’t sufficient for intimacy with the city’s entirety,the immersion into Zhongshan’s cultural,historical,and modern facets,including Zhongshan Museum,urban planning zones,business hubs,an industrial park,ancient villages,Dr.Sun Yat-sen Museum,and a monumental bridge project,left me with the impression that the city is awakening like a dragon ascending from the heart of Guangdong.

Research on the Digital Transformation of the Whole Industry Chain of Guangdong Supply and Marketing Cooperative

Guangdong Supply and Marketing Cooperative serves as an important institution for the“Three Rural Areas”in the Guangdong-Hong Kong-Macao Greater Bay Area.Its digital transformation and optimization serve as powerful supports for rural revitalization.This paper systematically reviews the main practices and effectiveness of the digital transformation within the Guangdong Supply and Marketing Cooperative.It also analyzes the current development dilemmas faced in the construction of digital supply and marketing.Additionally,it proposes targeted solutions,including building a big data resource base,optimizing the digital supply and marketing cloud platform,developing digital publictype agricultural social service applications,establishing a new model of rural e-commerce,enhancing the traceability management system for agricultural products,and strengthening the construction of the digital human resources system.These proposals aim to further promote the strategy for revitalizing the countryside.

Application of Traditional Chinese Culture in Cross-Cultural English Education:A Case Study of the Maritime Silk Road in Guangdong Province

The phenomenon of aphasia in Chinese culture is serious.The existing English teaching materials emphasize too much Western culture education and lack traditional Chinese cultural elements.Therefore,this paper takes the Guangdong Maritime Silk Road as an example to study the specific application of traditional Chinese culture in cross-cultural English education.This paper first summarizes the significance of cross-cultural integration into college English education and then points out the serious phenomenon of Chinese cultural aphasia.Next,the paper focuses on English education,using English textbooks as a starting point to explore and integrate strategies related to excellent traditional Chinese culture from the Guangdong Maritime Silk Road.By integrating traditional Chinese culture into business English classes(with the Guangdong Maritime Silk Road as an example),the study explores the influence of such cultural integration on students’cross-cultural communication skills,cultural identity,and learning effects.The results showed that the P value of the experimental group and the control group was<0.05,that is,cultural integration had a positive effect on improving the effect of cross-cultural English education.The overall scores and cultural confidence of the experimental group are higher than those of the control group,which proves that cross-cultural teaching has a positive effect on the improvement of students’scores.

Quantitative Research on Ecological Compensation among Every City of Guangdong Province Based on Ecological Footprint and Ecological Carrying Capacity

Based on the relative theories and methods of ecological footprint and ecological carrying capacity,and according to practical conditions of Guangdong Province,this paper tried to put forward the determinant standard for ecological compensation through calculating the ecological footprint and ecological carrying capacity of every city in Guangdong Province. The results indicated that the ecological footprint of each city was in the status of deficit and the deficit level decreased gradually from developed regions of Pearl River Delta to the outlying regions. The cities which belonged to development areas of Pearl River Delta needed to pay ecological compensation,such as Guangzhou and Shenzhen and so on. In contrast,the cities which accepted compensation were underdeveloped areas,such as Heyuan and Jieyuan and so on.

Prevention and Utilization of Invasive Plants of Agriculture and Forestry in Guangdong Province

Guangdong has become a major＂window＂ for invasive plants, and the largest zone, where cross-border and intercontinental migration frequencies reach the peak. The invasive plants in Guangdong are dominated by Mikania micrantha, Eichhornia crassipes, Alternanthera philoxeroides, Eupatorium odoratum, and Wedelia trilobata. It is an important way for treating the invasive plants by exploring the prevention methods and making ful use of the characteristics of the invasive plants, and it is of great significance to prevent and utilize alien species in a scientific and effective way in order to control the invasive plants with minimal cost.

禽流感病毒A/Goose/Guangdong/3/96(H5N1)NA基因克隆及序列分析

采用RT_PCR技术扩增了禽流感病毒A/Goose/Guangdong/ 3/ 96 (H5N1) (GD3/ 96 )NA基因 ,并对其进行了克隆与测序 ,该苷酸序列测定结果表明 :NA基因全长为 1410bp ,共编码 46 9个氨基酸。其序列与A/Hongkong/ 15 6 / 97(H5N1)、A/Chicken/HongKong/ 2 2 0 / 97(H5N1)、A/Goose/Guangdong/ 1/ 96 (H5N1)及A/teal/Hongkong/W312 / 97(H6N1)分离株核苷酸序列的同源性在88.4%～ 99.0 %之间 ,其相应氨基酸序列的同源性在 89.8%～ 99.2 %之间。氨基酸序列与香港流感分离株氨基酸序列相比 ,在茎部没有出现 19个氨基酸残基的缺失 。

Present status and conservation strategies of mangrove resource in Guangdong, P. R. China

According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.

Soil Environmental Quality Evaluation for Wasteland of Coalmine Tailing Polluted by Heavy Metals in Mingshan of Guangdong

ln order to appraise scientifical y the heavy metal contamination in waste-land of coalmine tailing in Mingshan of Guangdong, the 5 soil samples in wasteland of coalmine tailing were col ected in November 2010 to March 2011. The 7 heavy metals content in the contaminated soil was measured by atomic absorption spec-trophotometry. The results showed the pH of the wasteland soil ranged from 2.87 to 6.16, and the soil was relatively infertile. The soil was mainly pol uted by Cd and Mn. The Cd content in wasteland soil ranged from 0.759 mg/kg to 3.109 mg/kg with an average content of 2.052 mg/kg, which was much higher than the standard content. The Mn content ranged from 387.057 to 488.660 mg/kg with an average content of 421.215 mg/kg, which was much higher than the standard content. The Nemerow integrated pol ution indexes showed the sample 1, sample 4 and sample 5 were of heavy pol ution, and sample 2 and sample 3 were of moderate pol ution.

Analysis on the Landscape Fragmentation in Dongguan

The analysis of the landscape fragmentation in Dongguan could promote the sustainable development of its eco-environment,society and economy.Guided by the theory of landscape ecology,various landscape indices,including patch number,mean patch area,fragmentation index,fractal dimensions,boundary density,patch density,landscape diversity,landscape dominance and landscape fragmentation were selected to analyze the evolution features of landscape fragmentation in Dongguan.The research results revealed that the construction land kept intruding and assimilating farmland and natural landscape,the landscape patch number of study area was on the increase and the mean patch area reduced fast,so the landscape fragmentation degree of Dongguan was aggravated.After 1995,the land use speed slowed down,which indicated the study area started to focus on holistic development of city after drastic expansion.

THE "DIALOGUE" BETWEEN THE FIFTEENTH NATIONAL CONGRESS OF OCP AND GUANGDONG CUSTOMS——Interviewing Liu Wenjie, representative of the Congress, director of Guangdong Customs Branch Office, Director of Guangzhou Customs

The Fifteenth Natlonal Con-gress,a very important andgrand trans—century meeting inthe history Of CCP,was inaugu-rated in Beijing on September 12,1997. Guangdong Customs have sentrepresentatives to attend the Party’sCongress for the first time in his-tory.Among the two representa-tives is Liu Wenjie,director ofGuangdong CUStoms Branch Of-fice and of Guangzhou Customs.On September 23 after conclusionof the Coilgress,this reporter inte-Viewed directory Liu Wenjie in

Cancer incidence and mortality in Guangdong province,2012

Objective： To estimate the cancer incidence and mortality in 2012 in Guangdong province by analyzing the cancer data of selected population-based cancer registries in Guangdong province in 2012. Methods： Eight of nine population-based cancer registries submitted cancer data to the Guangdong Provincial Centre for Disease Control and Prevention （Guangdong CDC）, whose data met the data quality criteria were included for analysis. The statistics of selected registries, stratified by areas, gender, age and cancer types, were used to estimate the cancer incidence and mortality in 2012 in Guangdong province according to the population data in Guangdong province. Segi＇s population and the national census population in 2000 were used for calculating the age-standardized rates （ASR）. Results： A total of 15,084,942 people, accounted for 17.47% of all population in Guangdong province, were covered in 8 selected population-based cancer registries in 2012. The percentage of cases morphologically verified （MV%） and the percentage of death certificate-only cases （DCO%） were 72.84% and 0.87%, respectively, and the mortality/incidence （M/I） ratio was 0.56. It was estimated that there were 211,300 new cancer cases and 117,300 cancer deaths. The incidence crude rate （CR）, the ASR by Chinese standard population （ASRC） and by world standard population （ASRW）, and the accumulated rate （AR） （0-74 years） were 250.20/100,000 （265.39/100,000 in males, 234.29/100,000 in females）, 207.04/100,000, 201.34/100,000 and 22.91%, respectively, in Guangdong province in 2012. The incidence CR and ASRC were 267.25/100,000 and 221.43/100,000 in urban areas, and 215.51/100,000 and 178.77/100,000 in rural areas, respectively. The death CR, ASRC, ASRW and AR （0-74 years） were 148.44/100,000 （190.95/100,000 in males, 105.06/100,000 in females）, 103.73/100,000, 102.44/100,000 and 11.68%, respectively, in Guangdong province in 2012. The death CR and ASRC were 164.57/100,000 and 105.46/100,000 in urban areas, and 124.63/100,000 and 99.97/100,000 in rural areas, respectively. Top 5 cancers were lung cancer, liver cancer, female breast cancer, colon cancer and nasopharyngeal cancers （NPC）, and top 5 death cancers were lung cancer, liver cancer, colon cancer, stomach cancer, and NPC in Guangdong province in 2012. Conclusions： Lung cancer, liver cancer, female breast cancer, colon cancer and NPC were the major economic cancer burdens and health concerns in Guangdong province in 2012. Early prevention, diagnosis and treatment of different cancers, survival quality improvement and cancer burden reduction, are important issues we faced in cancer control and prevention.

Geochemical Characteristics and Genesis of the Luxi-Xianrenzhang Diabase Dikes in Xiazhuang Uranium Orefield, Northern Guangdong Province

The Luxi-Xianrenzhang diabase dikes were emplaced into the eastern part of the Guidong composite granitoids in northern Guangdong Province at the end of the Early Cretaceous. They show tholeiitic features, enrichment in large ion lithophile elements, slight enrichment in light rare earth elements, depletion in Zr and Hf, and basically no depletion in Nb and Ta and no Eu anomaly. They are similar to intraplate basalt in terms of trace element characteristics. They have high εNd（t） values （3.6-4.9）, initial ^87Sr/^86Sr ratios （0.70530-70641） and δ^18O values and Dupal anomaly of Pb isotope compositions. Their Sr-Nd, Pb-Sr, Pb-Nd and Pb-Pb isotopes plot between DMM and EMII, with Pb similar to EMII, Nd relatively close to DMM and Sr in between. This profile suggests that the diabase dikes studied were derived from partial melting of a mantle source that had been subjected to metasomatism by fluids originated from a subduction zone under a tectonic environment of crustal extension and lithosphere thinning in the late Yanshanian.

Spatial distribution of heavy metals of agricultural soils in Dongguan, China

Distribution and speciation of heavy metals of agricultural soils(85 surface soil samples and 4 soil profiles) in Dongguan were investigated, while total Cr, Cu, Ni, Pb, Zn(abbreviated as Cr, Cu, Ni, Pb, Zn) and available Cu, Zn(Av-Cu, Av-Zn) were analyzed by a flame absorption spectrophotometer(AAS), and total Cd(Cd) was analyzed using graphite furnace AAS. The content of Cd, Cu and Ni was partially much more than the second grade of GB15618-1995 even though the mean contents of all heavy metal were less than the threshold value of the second grade and only the mean content of Pb was more than the value of national background. Results of descriptive statistic showed that the mean content of heavy metals should depend on land utilization and spatial location at some extent. The heavy metal contents were higher in the Southwest and Northwest than in the Central. In addition, the mean contents of Zn and Pb in Dongguan paddy soils were significantly higher than those of Pearl River Delta(PRD) and Taihu Lake region(TLR). Correlation analyses indicated that there existed significant correlation between Cr and Ni in orchard soils, and among Zn, Cd and Cu, between Av-Cu and Cu, between Av-Zn and Cr, Ni, pH value in vegetable soils, and a weak relationship between Cd, Cu and Pb, between Av-Zn and Zn. Principal component analyses(PCA) showed that the order of importance should be Zn>Pb>Cr>Ni>Cu.

Environmental Correlates of Distribution of the 25 Broad-leaved Tree Species Indigenous to Guangdong Province,China

Twenty-five tree species indigenous to Guangdong Province were chosen in this study to portray their distribution patterns in relation to environmental factors. Both data of species distribution and environmental factors were tabulated based on a digitized map of Guangdong Province gridded at 0.5° latitude × 0.5° longitude. Grid-based diversity was mapped using DMAP, a distribution mapping program, and horizontal patterns were assessed using Kruskal-Wallis tests. The diversity center of the indige- nous tree species under study is located north of 23° N. These tree species exhibit significant latitudinal variation (P = 0.007 4), but no significant longitudinal difference (P = 0.052 2). Non-metric Multidimensional Scaling (NMS) identified five different ecological species groups, while Canonical Correspondence Analysis (CCA) showed the distribution of tree species along each of the five envi- ronmental gradients. An understanding of the environmental correlates of distribution patterns has great implication for the introduc- tion of the indigenous tree species for afforestation.

Late Paleozoic Fluid Systems and Their Ore-forming Effects in the Yuebei Basin,Northern Guangdong,China

Based on detailed and systematic researches of the geology of ore deposits, fluid inclusions and isotope geochemistry etc., and regarding the Late Paleozoic fluid system of the Yuebei Basin as an integrated object in this paper, we have revealed the temporo-spatial evolution law of the basin＇s fluid system and discussed its ore-forming effects by simulating and analyzing the distribution of ore-forming elements, the fluid thermodynamics and dynamics of evolution processes of this basin. The results show that Late Paleozoic ore-forming fluid systems of the Yuebei Basin include four basic types as follows. （1） The sea floor volcanic-exhalation system developed during the rapid basin slip-extension stage in the Mid-Late Devonian, which affected the Dabaoshan region. It thus formed the Dabaoshan-type Cu-Pb-Zn-Fe sea floor volcanic-exhalation sedimentary deposits. （2） The compaction fluid system developed during the stable spreading and thermal subsidence-compression stage of the basin in the Mid-Late Devonian. The range of its effects extended all over the whole basin. It resulted in filling-metasomatic deposits, such as the Hongyan-type pyrite deposits and pyrite sheet within the Fankou-type Cu-Pb-Zn-S deposits. （3） The hot water circulation system of sea floor developed during the stage of basin uplifting and micro-aulacogen from the late Late Carboniferous to Middle Carboniferous. The range of its effects covered the Fankou region. It thus formed MVT deposits, such as the main orebody of the Fankou-type Pb-Zn-S deposits. （4） The gravity fluid system developed during the stage of fold uplifting and the basin closed from Middle Triassic to Jurassic, forming groundwater hydrothermal deposits, e.g. the veinlet Pb-Zn-calcite orebodies of the Fankou-type Pb-Zn- S deposits. Migration and concentration of the ore-forming fluids were constrained by the state of temporo-spatial distribution of its fluid potential. Growth faults not only converged the fluids and drove them to move upwards, but also the fluids often crossed the faults to the edges of the basin at the bottom of these faults and the lithologic interfaces, and even migrated to the basin＇s edges from top to bottom along the faults, which may be one of the basic reasons for the stratabound deposits to cluster mainly along the contemporaneous faults on the inner border of the basin. The superposed mineralization resulting from the multi-stage activity of contemporaneous faults and ore-forming fluid systems in the basin may be one of the key factors for forming superlarge ore deposits.