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China, is characterized by its remarkable ethnical diversity, which necessitates whole genome variation data from multiple populations as crucial tools for advancing population genetics and precision medical research. However, there has been a scarcity of research concentrating on the whole genome of ethnic minority groups. To fill this gap, we developed the Guizhou Multi-ethnic Genome Database (GMGD). It comprises whole genome sequencing data from 476 healthy unrelated individuals spanning 11 ethnic minorities groups in Guizhou Province, Southwest China, including Bouyei, Dong, Miao, Yi, Bai, Gelo, Zhuang, Tujia, Yao, Hui, and Sui. The GMGD database comprises more than 16.33 million variants in GRCh38 and 16.20 million variants in GRCh37. Among these, approximately 11.9% (1,956,322) of the variants in GRCh38 and 18.5% (3,009,431) of the variants in GRCh37 are entirely new and do not exist in the dbSNP database. These novel variants shed light on the genetic diversity landscape across these populations, providing valuable insights with an average coverage of 5.5 ×. This makes GMGD the largest genome-wide database encompassing the most diverse ethnic groups to date. The GMGD interactive interface facilitates researchers with multi-dimensional mutation search methods and displays population frequency differences among global populations. Furthermore, GMGD is equipped with a genotype-imputation function, enabling enhanced capabilities for low-depth genomic research or targeted region capture studies. GMGD offers unique insights into the genomic variation landscape of different ethnic groups, which are freely accessible at https://db.cngb.org/pop/gmgd/. [ABSTRACT FROM AUTHOR]

The strip structure filling mining technology is suggested in response to the environmental issues such as surface subsidence and landslides brought on by the mining of 11,071 working faces in a mine in Guizhou. The mining technology system is studied through indoor testing, numerical simulation, and engineering monitoring. According to theoretical study, the filling strip can be steadily loaded and its value doesn't exceed 10 m when the width of the filling strip and the width of the filling interval are set to be equal. According to laboratory testing, fly ash can replace some of the cement in the cement mixture as a binder to maintain strength while cutting costs. The degree of crystallization gradually distributed into the network in the filling paste of various ages corresponds to its strength when combined with the findings of scanning electron microscopy; The numerical simulation results show that the maximum subsidence of the immediate roof is reduced from 340 to 3 mm from the filling rate of 0 to 100%, the filling effect is remarkable, and the shape of the settlement curve is changed from 'U' to 'basin', then to 'W'; during the local filling mining, the settlement curve of the immediate roof presents a 'wave' shape, and the stress curve of the immediate roof in the middle of the stope is also changed. The peak tension of the coal wall falls synchronously with filling spacing on both sides of the stope. The overall vertical stress below the mountain is larger, and the vertical stress at the top of the filling body eventually shifts from a "saddle" shape to a "inverted U" shape without zero support stress. In conjunction with the plastic zone, it is discovered that the stable bearing of the "filling strip-direct roof" composite structure increases with decreasing tensile and shear damage range of the hollow roof area and both sides of the top of the "filling 3 m interval 3 m" scheme; engineering measurement also reveals that the higher the position of the survey line is, the smaller the displacement is. However, the overall displacement of the strata directly above is negligible, and the greatest displacement is only 10.9 mm, which is consistent with the numerical simulation. At the same time, the displacement beneath the mountain area is too great. [ABSTRACT FROM AUTHOR]

The Guizhou Province is located in karst mountainous area, so it is very important for the future layout and planning of the city to study the underground geological structure of the city based on seismic detection technology. In this paper, taking the underground active fault detection in the Liupanshui City, Guizhou Province, China as an example, a set of appropriate evaluation techniques for the accurate spatial location, structural characteristics and latest activities of the fault suit for mountainous area are proposed. Through pre-stack noise suppression, amplitude fidelity and consistency processing, and multiple iterative analysis of velocity residual statics, the resolution of the geological structure of the underground rock has been significantly improved. Based on the detailed interpretation of the shallow seismic data and the regional geological analysis, it is concluded that the main fault strike of the Weining – Shuicheng section of the Weining - Shuicheng fault is NW, mainly normal fault, the dip direction is mainly southwest, partly northeast and the dip angle is 60-70°. The strata of the two fault plates are strongly compressed and broken, and the limestone and dolomite are generally recrystallized, and calcite veins and masses can be seen. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare health preferences for EQ-5D-5L health states between urban and rural populations in China. Methods: This study used pooled secondary data from two EQ-5D-5L valuation studies. Participants were recruited from Guizhou province and Chongqing municipality, China using quota sampling. Each participant was interviewed face-to-face to value a set of 15 or 16 out of 30 EQ-5D-5L health states using time trade-off (TTO) methods including composite TTO and other two variants. Regression analysis was used to compare health state preferences between urban and rural participants. Results: A total of 597 participants (urban: 55.44%; rural: 44.56%) completed the valuation interviews. Both univariate and multivariable linear regression analyses showed that rural participants tended to value health states lower than urban participants regardless of severity of health states. The unadjusted and adjusted overall mean differences between the two groups were − 0.041 (95% confidence interval [CI] − 0.077, − 0.004, p-value = 0.031) and − 0.040 (95% CI − 0.078, − 0.002, p-value = 0.038), respectively. Predictions for the 3125 health states based on rural participants' health preferences were lower than those based on urban participants' health preferences. Conclusion: There were small, yet statistically significant, differences in EQ-5D-5L health states preferences between urban and rural populations in China. Future study aiming at establishing a national value set should pay more attention to the sample representativeness. [ABSTRACT FROM AUTHOR]

Studying the dynamics of plant populations is crucial to the conservation and management of endangered plants. The diameter at breast height (DBH), tree height, crown width, and environmental factors of a total of 15 plots in five populations in Guizhou Province, China were measured in this study. The method of substituting diameter at breast height for age was used to divide the population into 7 age classes. The age structure, static life table, and relationship between the population characteristics and environmental factors of the Litsea coreana Levl. var. sinensis population were studied. Moreover, the time series model was used to predict the population dynamics. Results showed that the age structure of population in Zhengan County (Population ZA) had an inverted J-shape with abundant seedlings and insufficient middle-aged and elderly individuals. The age structures of populations in Daozhen County (Population DZ), Kaiyang County (KY), Meitan County (Population MT), and Xishui County (Population XS) were spindle-shaped with few young individuals and many middle-aged and elderly individuals. The mortality rate of each population fluctuated with the increase in age class, and the populations were extremely unstable. The survival curve was close to the Deevey III type, and the degree of deviation was related to the lack of young individuals. After the age stages II, IV, and VI, the number of aged plants in the different populations initially increased then decreased, and population stability was difficult to maintain. Redundancy analysis showed that the DBH, tree height and crown width of the population decreased with the increase of annual mean temperature, and the population density was restricted by soil nutrient conditions to a certain extent. The results of this work provide scientific basis for the conservation and sustainable utilization of natural populations of L. coreana var. sinensis in Guizhou Province, China. [ABSTRACT FROM AUTHOR]

In the present study, the concentration and accumulation abilities of five heavy metals (Cd, Hg, As, Pb, Cr) in rice were assessed and their human health risk to local citizens had been evaluated. Soil and rice samples (125 samples) were collected from Guiyang (GY), Qiannan (QN), Bijie (BJ), Tongren (TR), and Zunyi (ZY) in Guizhou Province. Heavy metals were measured by inductively coupled plasma–mass spectrometry (ICP-MS) after microwave digestion. The mean concentrations of Cd, Hg, As, Pb, and Cr were 0.58, 0.65, 12.31, 38.70, and 87.30 mg/kg in soil and were 0.05, 0.005, 0.11, 0.07, and 0.34 mg/kg in rice, respectively. The bioconcentration factors (BCF) decreased with the order Cd > Hg > As > Cr > Pb. Non-carcinogenic risk in this study was evaluated using the method of the hazard quotient (HQ) and hazard index (HI). The mean HQ values for Cd, Hg, Pb, and Cr were all lower than the standard limit (1.0) for children and adults, except As with the mean HQ for children of 2.79. The mean HI values for children and adults were 4.22 and 1.42, which exceeded 1.0. The mean carcinogenic risk (CR) values of As and Pb for children and adults were higher than the upper limit of the acceptable range (1 × 10−4) established by the United States Environmental Protection Agency (USEPA). In a conclusion, the non-carcinogenic and carcinogenic risks induced by heavy metals for children were higher than that for adults. This study revealed that consumption of rice in study areas may pose potential non-carcinogenic and carcinogenic risks to humans, and As was the largest contributor. [ABSTRACT FROM AUTHOR]

Landslides are one of the common geological disasters in Southwest China. Monitoring the formation and occurrence of landslides and developing prevention strategies are important issues of general interest to scholars in the field of geological disasters. At 8:41 p.m. on July 23, 2019, a destructive rainfall-triggered landslide occurred in Jichang of Shuicheng county, Guizhou province, Southwest China. The location and extent, sliding direction, and other relevant information of this landslide were obtained by visual interpretation from processed multitemporal images captured by unmanned aerial vehicles with real-time kinematics and optical image of the Chinese High-resolution Earth Observation Satellite II. The combination of imaging and pre-landslide and post-landslide images obtained through multisource remote sensing was employed to analyze the landslide characteristics in this work. Geometric correction, atmospheric correction, and orthorectification were applied to the images based on a 1:10,000 topographic map. The landslide volume was estimated from between pre-landslide and post-landslide digital elevation models. The findings showed that the projection area of the landslide was 32.0 × 104 m2. This landslide had a total runout distance of 1350 m along a vertical distance of approximately 499 m, and the total duration of the landslide was 60 s with an average velocity of 22.5 m/s. The landslide involved slope failure of approximately 1.8 million m3. An unspoiled mound with a surface area of 2.07 × 104 m2 was detected in the middle and lower parts of the Jichang landslide. The landslide could be characterized by a long runout and high position, induced mostly due to heavy rainfall and comprehensive disasters involving landslide and rock-debris flow. There is a potential failure risk of this landslide, and it is recommended to strengthen the precaution system employed for slope observation and mass prevention, so as to protect the lives and properties of residents. [ABSTRACT FROM AUTHOR]

The odd-pinnately compound leaves of short pod-branch surrounding the fruit growth of Roxburgh rose (Rosa roxburghii Tratt.) are the source organ of photosynthesis, and the photosynthetic capacity of leaves is an important factor determining the yield. To analyze the relationship between the distribution of palisade cells in different leaf positions and photosynthesis in the flowering and fruiting stage, the microstructure, photosynthetic physiology, and gas exchange parameters of each leaf position were measured. The leaves located in the middle of short pod-branches were rich in columnar cells and showed higher chlorophyll content and, thus, higher light absorption by the leaves than other leaf positions, which conducted to enhanced photosynthesis and outstanding photosynthetic capacity under sufficient light environment. Yet, the first leaf was immature, and the differentiation of mesophyll cells was not completed, which resulted in a weakening of photosynthesis per unit leaf area under adiquate light environment. The lower leaves of short pod-branches showed smaller leaf area and looser spongy mesophyll in an environment with light blocking, which resulted in insufficient photosynthetic capacity. Our findings indicate that the photosynthetic conversion ability of the middle leaf of short pod branch is the most prominent. Therefore, regulating leaf mesophyll cells distribution according to leaf position is essential for effective leaf photosynthesis at the flowering and fruit stage in Roxburgh rose. [ABSTRACT FROM AUTHOR]

Long-term exposure to heavy metals from high geological background area may lead to varieties of diseases. Therefore, risk assessment from agricultural products in these areas was crucial to ensure the health of customers. However, the effects of geological background on distributions of heavy metals and their accumulation in plant remain unclear. This study aimed to determine the distributions of mercury (Hg), cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr) and copper (Cu) in 1036 corn and rice samples collected from 9 locations in Guizhou province and to evaluate their health risks. The concentrations of Hg, Cd, As, Pb, Cr and Cu in these two crops were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), and their health risk were estimated by the target risk quotient approaches. Results showed that the mean concentrations of Hg, Cd, As, Pb, Cr and Cu in corn and rice were 0.01, 0.07, 0.06, 0.27, 0.56 and 1.86 mg/kg which were lower than their respective maximum allowable concentrations (MAC) of 0.02, 0.20, 0.70, 0.20, 0.50 and 10.00 mg/kg except Pb and Cr. The concentrations of Cr and Cu in corn were higher than in rice while Cd, As and Pb in rice were higher than in corn. Moreover, the distributions of Hg, Cd and Cu in corn and rice samples were mainly observed from QDN located at southeast of Guizhou province while Pb, As and Cr were most detected at ZY, QXN and BJ areas, southwest zone. The hazard indices (HIs) values for corn and rice were 0.20 and 2.61. The high HIs (> 1) in rice indicated that the health risk of heavy metals in rice was relatively high and Pb was the major component that attributed to the risk, followed by Cd. These results could provide a reference for the distributions of heavy metals in agricultural products in Guizhou province under crop cultivation conditions, and to provide scientific basis for health risk assessment and ensure food safety. [ABSTRACT FROM AUTHOR]

Farmland soils that surround a historical zinc smelting area in northwestern Guizhou, China, are characterized by high levels of heavy metal accumulation. Previous studies have mainly focused on the potential risk evaluations of heavy metals in soil and crops. However, at present, the effects of amendment applications on the bioavailability of heavy metals and on microbial community in the heavily contaminated soils of the mining region are still unclear. A pot experiment was conducted to determine the effect of applying a combined amendment (e.g. lime, sepiolite, and vermicompost) on the diversity and composition of microbial community in the contaminated soil. The results showed that the contents of DTPA- and TCLP-extractable heavy metals (e.g. Cd, Pb, and Zn) decreased and that the pH, SWC, EC, and soil available nutrient (e.g. AN, AP, and AK) contents increased after the application of the combined amendment. Furthermore, application of the combined amendment decreased the diversity of soil bacterial and fungal communities and increased the relative abundances of the dominant bacterial and fungal communities such as Proteobacteria, Bacteroidetes, and Ascomycota; however, the relative abundances of Acidobacteria and Actinobacteria decreased. Redundancy analysis (RDA) and structural equation model (SEM) analysis showed that the bioavailability of heavy metals decreased and that soil physicochemical characteristics improved and had positive or negative effects on the diversity and composition of soil microbial community. [ABSTRACT FROM AUTHOR]

Smelting of nonferrous metals causes significant concerns because of its emissions of heavy metals (HMs) into surface soil, and its potential threat to human health through the food chain. To investigate the HMs concentrations in a soil-maize system, a total of 41 paired soil-maize samples were collected from a typical indigenous zinc-smelting area of northwestern Guizhou Province, China. Results showed that the concentrations of the targeted HMs in the soil were significantly higher than their corresponding background values of Guizhou Province. Results obtained of the geo-accumulation index (Igeo) and the potential ecological risk factor of an individual metal (Eri) revealed that Cd and Pb were identified as the top-priority control HMs in the study area. The mean concentrations in maize grain decreased in the order of Zn > Pb > Cu > Cd. Bio-accumulation factor (BAF) indicated a strong ability for Cd to be accumulated in the maize root. Translocation factor (TF) and Fourier transform infrared (FTIR) spectroscopy revealed that the maize root played an important role in reducing the mobilization of HMs to stem, except for Zn. Kriging interpolation results illustrated that the spatial distribution patterns of HMs in the maize grain were generally similar to those in sampled soil, and the higher concentrations for the investigated HMs were partially overlapping between soil and maize grain. The average hazard quotient (HQ) of the investigated HMs for both children and adults were all lower than the threshold value (HQ = 1). The total hazard index (HI) was 5.51E-01 and 4.24E-01 for the two population groups, respectively, implying no potential non-carcinogenic risk for local maize-consumers. Sensitivity analysis demonstrated that the oral ingestion rate (IngR) of grain was the predominated contribution to the output of the risk assessment. [ABSTRACT FROM AUTHOR]

Exposure to arsenic-contaminated air and food caused by the burning of coal in unventilated indoor stoves is a major environmental public health concern in Guizhou Province, China. The liver is one of the main target organs for coal-fired arsenic exposure; however, there is little information about the risk assessment between cumulative arsenic exposure and the prevalence of liver damage. This study first evaluated the chronic daily intake (CDI) for two exposure pathways (inhalation and ingestion) and five environmental media (i.e., indoor and outdoor air, drinking water, rice, corn, and chili peppers) in 1998, 2006, 2014, and 2017. Then, the dose-effect and dose-response relationship between hair arsenic (HA) and cumulative arsenic (CA) levels and liver damage was analyzed. The results clearly show that the CDI in 1998 was 34.9 μg·kg−1·d−1, 22.9 μg·kg−1·d−1 in 2006, 11.7 μg·kg−1·d−1 in 2014, and 6.7 μg·kg−1·d−1 in 2017 in the arsenic exposure area. All of these values were higher than the daily baseline level of 3.0 μg·kg−1·d−1 as recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), and the increased HA and CA can increase the risk of coal-fired arsenic-induced liver damage. In addition, we analyzed the possible maximum acceptable CA exposure level for coal-fired arsenic-induced liver damage using the Bayesian benchmark dose. The recommended maximum acceptable CA exposure level for liver damage caused by coal-burning arsenic is 7120 mg. This study provides scientific insight into understanding the dose-response relationship of liver damage caused by coal-burning arsenic exposure and the monitoring and prevention of arsenic poisoning. [ABSTRACT FROM AUTHOR]

A rock avalanche that destroyed 23 houses and killed 35 people occurred on 28 August 2017, Nayong, SW China. Combined with the dynamic parameters from seismic signal inversion, a discrete element model, MatDEM was used to determine the rock avalanche's kinematic behavior. Although the dynamic process obtained through inversion will be disturbed by factors, such as rockfall from the source area, by comparing the velocity of rock avalanche versus horizontal distance traveled, the best combination of parameters was selected from different values given. The dynamic process obtained by modeling was compared with the nearest seismometer frequency distribution spectrum, showing that the dynamic process is in good agreement with those parameters inverted from seismic signals. The simulation results show that the movement process lasted for nearly 40 s, with a maximum speed of 40 m/s. This model of selecting parameters contributes to explain the dynamic processes of similar rock avalanche more accurately and is of great significance to the hazard prediction in the karst area. [ABSTRACT FROM AUTHOR]

Aim to classify typical hot springs in Guizhou, China and their relevance to health. Assessing geochemical characters of typical hot springs of Guizhou and classifying through hierarchical cluster analysis, an epidemiologic study was conducted to analyze the correlation between hot spring types and health, which showed typical hot springs in Guizhou can be divided into two types, A and B. Type A is rich in fluorine, metasilicic acid, radon components and a large number of essential elements, such as Na, that the human body needs, with trace elements, such as Cr and V, that are essential or possibly essential. Type B is rich in fluorine, metasilicate, strontium components and a large number of essential elements, Ca, Mg, and S, with trace elements, Cu, Mn, Mo, Co, and Ni, that are essential or possibly essential. These hot springs' effects on the health of those bathing in them showed both types were associated with bone and joint diseases. Having bathed in hot springs during the past year was associated with skin symptoms and bone and joint symptoms, and having bathed within the past two weeks was linked to sleep quality and levels of appetite and energy. However, differences do exist between the correlation between the two types and some chronic diseases, with Type A hot springs significantly related to cardiovascular and cerebrovascular diseases and diabetes and Type B to hypertension. This classification of Guizhou's hot springs can guide the future development and use of hot spring physiotherapy. [ABSTRACT FROM AUTHOR]

Land use affects the accumulation of heavy metals in soil, which will endanger ecological safety and human health. Taking the village as an administrative unit, the ecological safety and health risks of heavy metals, namely, Cr, Cu, Zn, and Pb in soils in the Houzhai River Watershed of Guizhou Province, China, were evaluated based on land use types by the Hakanson potential ecological risk methods and human health risk model. Results showed that the spatial heterogeneity of Cu and Zn was greatly affected by primary structural factors, and Cr and Pb were interfered by both structural factors and human activities. The geo-accumulation index of the heavy metals showed a light pollution in the study area. The comprehensive potential ecological risk of heavy metal in the area was divided into three levels: slight, moderate, and intense, and it is spatially high in the northwest and low in the southeast. Both non-carcinogenic risk and carcinogenic risk of the heavy metals to the human body are not significant and are acceptable. The risks of children are higher than adults, and direct intake is the primary route of exposure in the area. The potential ecological risk and human health risk of soil heavy metals are relatively obviously affected by digital elevation data and normalized vegetation index. The study has certain reference value for the prevention and control of regional soil heavy metal risk. [ABSTRACT FROM AUTHOR]

To estimate carbon sequestration potential in the karst area, soil respiration in a natural recovering karst abandoned farmland in Shawan, Puding, Guizhou, southwest China was continuously and automatically monitored for more than two years. The results show that the CO2 flux of soil respiration (2.63 ± 1.89 μmol m−2 s−1) is higher in the karst area than in non-karst areas under similar conditions but that regional value (1.32 μmol m−2 s−1) is lower because of larger rock fragment coverage (~ 50 %). At the same time, the temperature sensitivity of soil respiration (Q10) in this study area is significantly higher than that of non-karst areas under similar conditions. Soil respiration has an obvious temporal variation, which is reflected in a significant exponential relationship between soil respiration and soil temperature, but the relationship between soil respiration and soil moisture is very complex. Especially, soil respiration has an obvious spatial variation, which is likely affected by different diffusion or water–rock reaction processes. [ABSTRACT FROM AUTHOR]

The placement of the Ediacaran-Cambrian boundary in deep-water realm in South China and the high-precision temporal framework for the Ediacaran-Cambrian transition in this region have not yet been completely solved. Recently, we have found two K-bentonite beds in the top of the Liuchapo Formation at the Pingyin section, Guizhou Province. It provides an opportunity for constructing the temporal framework of the transitional strata on the Yangtze Platform in South China and for determining the Ediacaran-Cambrian boundary in this area. In this study, we conducted high-precision CA-ID-TIMS U-Pb dating on zircons from the two K-bentonites. The ages of the two K-bentonites were precisely constrained at 536.40±0.47/1.1/1.2 Ma (2σ, n=7, MSWD=0.92) and 541.48±0.46/1.1/1.2 Ma (2σ, n=8, MSWD=1.3). Combining the geochronological results with organic carbon isotope data of chert in the topmost Liuchapo Formation from the section, we suggest that the EdiacaranCambrian boundary should be consistent with a significant negative organic carbon isotope excursion between the two K-bentonites. The scheme of the Ediacaran-Cambrian boundary in this study is of great significance for global correlation, and further for unravelling the information of the terminal Ediacaran-early Cambrian ocean. [ABSTRACT FROM AUTHOR]

Discussing the spatiotemporal change characteristics of slope cultivated land use transition influenced by various factors in karst trough valley area is of great importance and can help in regional food security and ecological restoration. High-resolution images (0.53 m) of 2005, 2010, and 2017 and a digital elevation model as the data source were verified through a field survey. We calculated the relevant dynamic change index and used the transfer matrix and kernel density estimation to reveal the spatial temporal transition characteristics and spatial agglomeration of slope cultivated land in the trough valley area of Guizhou Province, China. Results show that the utilization of slope cultivated land is mainly dominated by gentle and oblique slope cultivated lands. From 2005 to 2017, the dynamic degree changes of slope cultivated land show their own characteristics and differences. The transition of slope cultivated land is mainly based on rural residential land, town land, fruit land, tea land, shrubland, grassland, and forested land, the transfer space is distributed in the flat position of three trough valleys, and the change in density agglomeration during 2010–2017 is higher than that during 2005–2010. Six change modes are found in the temporal and spatial variations of slope cultivated land. The difference distribution of natural factors in elevation, hydrogeology, and soil type directly leads to the significant difference in the spatial and temporal distributions of slope cultivated land. The utilization function of slope cultivated land shows diversification with the improvement of social economy and the implementation of human policies in trough valley areas. [ABSTRACT FROM AUTHOR]

The deposition and release of heavy metals in sediments often lead to their diffusion in lakes, especially for dispersed elements such as cadmium (Cd), which indirectly introduces pollutants into the food chain. The high rate of deposition or release of heavy metals in sediments is a problem to be solved. Southwest China is most famous in the world for the continuous distribution of karst area, for holding the largest area of bare carbonate rocks and for experiencing the strongest karst development in the world. The trace metals in 15 sites of Yelang Lake were determined by diffusive gradients in thin-films (DGT) method. The distribution and release mechanism of Cr, Ni, Cu, Cd, Zn and Pb under high geochemical backgrounds in the karst area of Guizhou Province in Southwest China were discussed. Based on the DGT concentration and pore water analysis, the distribution order of these heavy metal contents is usually upstream (SC), middle (DCB) and downstream (SW) areas of the lake, which increases during the dry season and decreases during the wet season. There was no significant difference in concentration between 0–4 and 4–8 cm depth (p < 0.05). The R values of heavy metals in the dry and wet seasons were highest with cadmium (Cd) and lowest with chromium (Cr) and lead (Pb). The results of the metal geo-accumulation index (Igeo) and the potential ecological risk index are highest on Cd and lowest on Cr. The mean concentrations of Cr, Cd, Zn, Ni (DCB, SW), Pb (SC, DCB) and Cu (SC) are between the corresponding threshold effect level and the probable effect level, and the average potential ecological risk is ranked in descending order of Cd > Pb > Zn > Cu > Ni > Cr. These three areas are at medium risk levels and the potential ecological risks increases from upstream to downstream. The deposition rate of heavy metals in Yelang Lake sediment was higher than the release rate and the ecological risk from heavy metals was relatively low. Since Cd is the main ecological risk factor in the lake, more attention needs to be given to Cd contamination in the Yelang Lake basin of the karst area. [ABSTRACT FROM AUTHOR]

The current studies had already revealed the hydrocarbons could migrate from relatively high hydrocarbon potential stratum to shallow groundwater by corrosion emission and extraction emission in karst area and further impact on human health. Then, the comprehensive experiments were used to understand the mechanism and process of hydrocarbon emission as a continuation of a long-term study on original high hydrocarbon groundwater in shallow Triassic aquifer, taking northwest Guizhou, China, as a reference. The results determined water-rock interaction that lead to the hydrocarbon emission into groundwater with salinity acting as the main driving force. Relatively high salinity promotes the rock corrosion and hydrocarbon emission in the study area. The hydrocarbon emission process varied with different strata, as the results show that the hydrocarbon uniformly distributed in T2g3 than that in T1yn4. Furthermore, the stratum with uniformly distributed hydrocarbon would likely contain high hydrocarbon groundwater, as determined by the process of sedimentation. In addition, "corrosion rate estimation method" and "mineral constituent estimation method" were firstly employed to estimate the hydrocarbon concentration in groundwater to date. Compared with the hydrocarbon concentration of local groundwater samples (0 to 0.14 mg L−1), the result of "mineral constituent estimation method" was analogous to measured value of groundwater samples in the area (0.05 to 0.50 mg L−1), indicating the concentration of hydrocarbon could be estimated by mineral constitutions of groundwater, which was related to the concentration of Ca2+ and Mg2+. Based on the methods and theories in this study, the concentration of original hydrocarbon in shallow groundwater could be estimated and help to understand the mechanism of water-rock interaction in shallow aquifer and original high hydrocarbon groundwater strategic assessment. [ABSTRACT FROM AUTHOR]

Large-scale transportation infrastructure construction in ecologically vulnerable areas such as the karst region of Southwest China requires estimation method for better project design. This research was carried out on a four-lane highway (the Guilin-Guiyang highway, G76) and a two-lane high-speed railway (the Guilin-Guiyang high-speed railway, GGHSR) in karst areas in Guizhou and Guangxi provinces. The highway and high-speed railway were constructed in the 2010s and covered by Landsat images whose multispectral information could be used for research purposes. In this study, the severity of the impact and the CO2 emissions from the G76 and GGHSR construction were evaluated. Landsat images and field meteorological measurements were applied to calculate the surface functional parameters (surface temperature and surface wetness) and heat fluxes (latent, sensible and ground heat flux) before and during the highway and high-speed railway construction; the amount of CO2 emissions during the G76 and GGHSR construction were determined by using budget sheets, which record the detail consumptions of materials and energy. The results showed that the decrease of water evaporation from the highway and high-speed railway construction can reach up to 26.4 m3 and 20.1 m3 per kilometer, which corresponds to an average decrease in the vegetation cooling effect of 18.0 MWh per day per highway kilometer and 13.7 MWh per day per high-speed railway kilometer, respectively. At the meantime, the average CO2 emission densities from the G76 and GGHSR construction can reach up to 24813.7 and 36921.1 t/km, respectively. This study implied that extensive line constructions have a significant impact on the local climate and the energy balance, and it is evident that selecting and planting appropriate plant species can compensate for the adverse effects of line constructions in karst mountain regions. [ABSTRACT FROM AUTHOR]

Wolbachia is a maternally inherited intracellular bacterium (Rickettsiaceae) that infects a wide range of arthropods and nematodes, plays an influential role in host development and triggers various reproductive abnormalities. In this study it was investigated whether Wolbachia infection of the Nilaparvata lugens (Stål) species of Guizhou brown planthopper (BPH) induces cytoplasmic incompatibility (CI) and alters BPH developmental timing, longevity, and fecundity. It was shown that although Wolbachia does not induce CI in the species of BPH, its absence decreases BPH fitness. Furthermore, the cross of a Wolbachia -free female BPH and an infected male (F▽ × M) resulted in a significantly shorter pre-adult developmental period (11.15 ± 0.22), significantly reduced ovi-days (5.80 ± 0.2438), significantly shorter longevity (22.9 ± 0.38), and lower fecundity (176.28 ± 5.79b). This cross also affected a series of population parameters by increasing the finite rate (λ) (1.2903 ± 0.02) and intrinsic rate value (r) (0.2548 ± 0.01), reducing the net reproductive rate (R 0) (88.12 ± 19.9) and decreasing longevity (22.9 ± 0.38). [ABSTRACT FROM AUTHOR]

Aims: The consumption of rice grain produced in mercury (Hg) contaminated soil was identified as a major route of dietary Hg exposure. The aims were 1) to determine the most suitable concentration of Se that can lead to least Hg accumulation in rice grain in real Hg contaminated paddy field in Qingzhen, and 2) to elucidate the possible mechanism of the protection against the phytotoxicity of Hg in rice by Se. Methods: Rice plants were treated with different concentrations (0, 0.01, 0.1, 0.5, 1 and 5 μg/mL) of sodium selenite in a real paddy field in Qingzhen, Guizhou, China. The concentrations of Hg and Se in soil, stream water, rice tissues, and the seed setting rate (SSR) and thousand seed weight (TSW) were checked. The distribution and chemical forms of Hg and Se in rice root were studied by XRF and XAS. Results: Treating the rice plants with 0.5 μg/mL of sodium selenite achieved the lowest Hg accumulation in rice grain while the highest SSR and TSW. In rice root, XRF found decreased Hg uptake, and XAS found Hg-Se complexes were formed. These findings, together with the formation of biological barriers like iron plaque, could explain the decreased accumulation of Hg in rice grain at Se levels below 0.5 μg/mL. Se concentrations over 0.5 μg/mL led to increased Hg accumulation and decreased SSR and TSW, which were ascribed to the significantly increased Se accumulation in rice grain. Conclusions: This field study suggest that treatment with appropriate level of Se (0.5 μg/mL in this study) is an efficient way to reduce Hg accumulation in rice and increase rice yield and quality, thereafter to protect the health of the rice-dependent populations in Hg-contaminated area. [ABSTRACT FROM AUTHOR]

This study mainly aimed to research the CDS sequence (coding sequence), polymorphisms of exon 1, exon 2 and part of exon 8 of GFI1B in GuiZhou white goat of indigenous Chinese goat. The cDNA of GFI1B was analysed through bioinformatics which was obtained by the reverse transcription PCR (RT-PCR). The polymorphisms of GFI1B gene exons region was identified whose association with growth traits was analysed by GuiZhou white goat. The results revealed that the cDNA of GFI1B which contained a complete open reading frame (ORF) was 996 bp in full length. The accession numbers on GenBank was JX627316. One new mutation sites of C347A had been determined in the eighth intron. Our results could lay the foundation for the further investigation on the role of GFI1B gene in goat growth traits. [ABSTRACT FROM AUTHOR]

Soil water and cave drip water from four cave systems in Guizhou, Southwest China, were monitored and sampled monthly from April 2003 to May 2004 to understand spatio-temporal variations in hydro-geochemistry of cave percolation water. The results indicated that among the 5 drip water sites from the Liangfeng Cave (LFC), there were no significant differences among the hydro-geochemical parameters. In the Xiniu Cave (XNC), the drip rates were variable and responded quickly to precipitation events in the 3# (No. 3) drip site with variable water head; both bulk and variation in drip rates were smaller in the 2# with constant water head. However, in the Qixing Cave (QXC) and Jiangjun Cave (JJC), drip rates, concentrations of major ions and saturation index for calcite (SIC) were smaller, and Mg/Ca ratios in Group I (1#, 2#, 6#, 7# and 8# in the QXC; 2# and 3# in the JJC) were larger than those in Group II (3#, 4#, 5# and 9# in the QXC; 1# and 4# in the JJC). These differences might be the result of different hydrogeological processes above the caves, which are divided into five categories based on hydro-geochemistry data. The formation of some proxies in speleothem, such as Mg/Ca, is likely to be affected by those processes. [ABSTRACT FROM AUTHOR]

The strontium isotopic compositions (87Sr/86Sr) of samples including soils, bedrock, soil waters, drip waters and their corresponding speleothems in the Qixing Cave (QXC), Guizhou Province, China, were systemically measured and analyzed. The results indicate that there are significant Sr isotopic differences among samples. The mean 87Sr/86Sr ratios in drip water for the samples 1#, 4# and 9# were 0.709568, 0.709139 and 0.708761, respectively, which possibly result from different flow paths, residence times, and other hydrogeological processes in the unsaturated zone overlying QXC. Meanwhile, levels of 40.8%, 57.6% and 72.4% of Sr in drip waters for 1#, 4# and 9#, respectively, were derived from bedrock dissolution, which was calculated by the mixture model of the two end-members (soil and bedrock). There is, however, no positive correlation between the relative proportion from bedrock dissolution (δ13C value is 1.8‰) and drip water δ13CDIC values. The mean drip water δ13CDIC value in 1# is the heaviest (-4.5‰) with the lowest contribution rate of bedrock dissolution, whereas the value in 9# is the lightest (-9.3‰) with the highest contribution rate of bedrock dissolution. The proportion from host rock dissolution in 4# is higher than that in 1# and lower than that in 9#, while its mean drip water δ13CDIC value (-8.6‰) is higher than that of 9# and lower than that for 1# . This suggests that the prior calcite precipitation (PCP) processes in the unsaturated zone overlying the cave are responsible for the δ13CDIC value differences between different drip waters, and not bedrock dissolution. Furthermore, this study also demonstrates that the 87Sr/86Sr ratios of speleothems in the 1# and 4# mainly reflect the variation in the relative proportions from the soil system (soil water) and bedrock dissolution overlying the cave. It is, therefore, feasible to use the strontium isotopic signals of speleothems as an indicator for soil chemical weathering intensity, and consequently as a monsoon proxy in the study area. [ABSTRACT FROM AUTHOR]

A new fern species, Polystichum puteicola (sect. Haplopolystichum, Dryopteridaceae), is described from a karst sinkhole in northwestern Guizhou, China. The new species is morphologically similar to P. obliquum, a species disjunctly occurring in limestone areas in Taiwan, southwestern China to the western Indo-Himalaya. Polystichum puteicola has lamina not contracted towards base (with the largest basal pinnae), petiole scales dark brown adaxially, rachis scales up to 3.6 × 0.8 mm, pinnae dark green, subcoriaceous, lustrous adaxially, and slightly repand or almost entire on margin, and microscales up to 2 × 0.5 mm. In contrast, P. obliquum has lamina with basal pinnae contracted, scales of petiole brown adaxially, scales of rachis up to 2.3 × 0.5 mm, pinnae green, chartaceous, matt adaxially, and serrulate on margin, and microscales 0.2-0.5 × 0.1-0.2 mm. Most interestingly, the two species differs in seven positions in the DNA sequences of chloroplast trnL-F intergenic spacer. Our phylogenetic analysis shows that the two species are even not closely related. Palynologically, P. puteicola has cristate sculpture with numerous spinules on its perispore. Features of the new species in geographical distribution, ecology, spore morphology, and trnL-F sequence are given. Conservation assessments are also presented following the IUCN guidelines. [ABSTRACT FROM AUTHOR]

In this paper, the role of pH value on the adsorption of Hg2+ on the laterite from Guizhou Province was studied. The lower pH is unfavorable to the adsorption of Hg2+ whereas the higher pH is favorable to the adsorption of Hg2+. When pH reached a certain value, the amount of Hg2+ adsorption reached the maximum. Then the amount of Hg2+ adsorption was reduced with increasing pH value. [ABSTRACT FROM AUTHOR]

In rainy season, NaCl is adopted to trace sources of cave drip water, time scales of drip water responding to precipitation, and processes of water dynamics in four caves of Pearl watershed in Guizhou, China (Liang-feng cave in Libo, Qixing cave in Duyun, Jiangjun cave in Anshun and Xiniu cave in Zhenning). Because of the variety of karst cave surroundings, interconnections of water transporting ways, water dynamics processes etc., time scales of drip-water in four caves responding to rainfall is O-40 d. According to the characteristics of water transport in cave roof, pathways of water movement, types of water head etc., drip water of four caves can be divided into five hydrodynamics types. The differences of time scales, and ways of water-soil and water-rock interaction during water transporting in cave roof make it difficult to correctly measure speleothem record and trace material sources. In addition, there exist great differences in water dynamic conditions among the four caves. So the interpretation of the paleoenvironment records of speleothem must be supported by the understanding of hydrodynamics conditions of different drip sites. Based on the data got from drip sites in four caves, drip conductivity accords with precipitation, which indicates that element contents in speleothem formed by drip water record the change of karst paleoenvironment. But results of multi-points study are needed to guarantee the correctness of interpretation. [ABSTRACT FROM AUTHOR]

Fungal endo-β-1,4-xylanases (endo-xylanases) can hydrolyze xylan into xylooligosaccharides (XOS), and have potential biotechnological applications for the exploitation of natural renewable polysaccharides. In the current study, we aimed to screen and characterize an efficient fungal endo-xylanase from 100 natural humus-rich soil samples collected in Guizhou Province, China, using extracted sugarcane bagasse xylan (SBX) as the sole carbon source. Initially, 182 fungal isolates producing xylanases were selected, among which Trichoderma sp. strain TP3-36 was identified as showing the highest xylanase activity of 295 U/mL with xylobiose (X2) as the main product when beechwood xylan was used as substrate. Subsequently, a glycoside hydrolase family 11 endo-xylanase, TXyn11A, was purified from strain TP3-36, and its optimal pH and temperature for activity against beechwood xylan were identified to be 5.0 and 55 °C, respectively. TXyn11A was stable across a broad pH range (3.0–10.0), and exhibited strict substrate specificity, including xylan from beechwood, wheat, rye, and sugarcane bagasse, with Km and Vmax values of 5 mg/mL and 1250 μmol/mg min, respectively, toward beechwood xylan. Intriguingly, the main product obtained from hydrolysis of beechwood xylan by TXyn11A was xylobiose, whereas SBX hydrolysis resulted in both X2 and xylotriose. Overall, these characteristics of the endo-xylanase TXyn11A indicate several potential industrial applications. [ABSTRACT FROM AUTHOR]