Spatial and Temporal Variation of Soil Salinity During Dry and Wet Seasons in the Southern Coastal Area of Laizhou Bay, China

260-270The southern coastal area of Laizhou Bay is subjected to severe soil salinization due to saline groundwater. The degree of spatial variability is strongly affected by seasonal changes during an annual cycle. In this paper, the spatio-temporal variability of soil salinity in Laizhou Bay, China, was examined to ascertain the current situation of soil salinization in the study area and to reveal the characteristics of seasonal variation of soil salinity. The classical statistical methods and geostatistical methods were applied to soil salinity data collected from four soil layers, i.e., 0-30, 30-60, 60-90, and 0-100 cm, during summer and autumn in 2014. The results indicated that the variation of soil salinity of all the soil layers in summer and autumn was moderate. The soil salinity in the 0-30 cm layer showed a moderate spatial autocorrelation, whereas the spatial autocorrelations of soil salinity in other layers were strong. The overall spatial distribution of soil salinity showed a clear banding distribution and the degree of salinization in the eastern area was lower than that in the western and northern regions.A high ratio of evaporation/precipitation is one of the important reasons for the soil salinity in July is significantly higher than that in November. The rank of soil salinity under different land-use types was: salt pan > orchard > weeds > soybean > woods > cotton > maize > ginger > sweet potato. The research findings can provide theoretical guidance for accurate assessment and soil partition management of regional soil salinization

Distribution of 222Rn in Seawater Intrusion Area and Its Implications on Tracing Submarine Groundwater Discharge on the Upper Gulf of Thailand

AbstractRadon (222Rn) has been widely employed as a tracer for estimating submarine groundwater discharge (SGD). However, the uncertainty of the SGD estimation remains significant, due to the spatial variability of radon in groundwater. In this study, we analyzed the hydrochemical proprieties of seawater and coastal groundwater in the Upper Gulf of Thailand and discussed the distribution characteristics of 222Rn in aquifers in terms of aquifer lithology, groundwater system recharge conditions, and water retention time. The results suggested that the residence time of groundwater and the process of groundwater salinization have the greatest impact on the distribution of 222Rn activity. A 222Rn mass balance model, synthesizing the distribution characteristics of 222Rn in groundwater and tidal influences on SGD, was built to estimate the submarine groundwater discharge in the Upper Gulf of Thailand. The result showed that the SGD flux of the Upper Gulf of Thailand was 0.0203 m/d. Moreover, there is a positive correlation between tidal height and the activity of 222Rn in groundwater. The SGD observed during the low tide was about 1.25 times higher than that observed during the high tide. This may influence the marine geochemical cycles of elements and their impact on marine ecosystems

Hydrochemical Characteristics and Quality Assessment of Groundwater under the Impact of Seawater Intrusion and Anthropogenic Activity in the Coastal Areas of Zhejiang and Fujian Provinces, China

AbstractCoastal groundwater is an important resource in the developed region associated with human health and sustainable economic development. To identify the origins of salinity and evaluate the impact of water-rock interactions, seawater intrusion (SWI), and evaporation on groundwater in the coastal areas of Zhejiang and Fujian provinces, a comprehensive investigation was performed. Meanwhile, nitrate and fluoride indicators resulting from the anthropogenic activity and SWI were also considered. At last, the water quality index (WQI) of coastal groundwater was evaluated with geochemical and multivariate statistical methods. The results indicated that (1) the groundwater in coastal areas of Zhejiang and Fujian provinces has been affected by SWI to varying degrees. The analysis of selected ion ratios (Na+/Cl− and Br−/Cl−) and isotopic compositions showed that SWI is the predominant cause of increasing salinity in the groundwater of Zhejiang Province, while the cause is water-rock interactions (ion exchange and mineral weathering) in Fujian Province. The hydrochemical evolution path of groundwater in Zhejiang Province is Ca/Mg-HCO3 to Na-Cl, while a different pattern of Ca/Mg-HCO3 to Na (Mg/Ca)-Cl occurs in Fujian Province. However, the trend of SWI development in both provinces was freshening. (2) Nitrification, sewage infiltration, and SWI increased the NO3− content in groundwater. Some of the NO3− concentration in Fujian Province exceeds the standard, and the nitrogen pollution was more serious than in Zhejiang Province. The F− content in coastal groundwater was affected by SWI and mineral dissolution; the F− content in Zhejiang Province was higher than in Fujian Province, which was close to the groundwater standard limit. The average WQI value of Zhejiang was 103.61, and the WQI of Fujian was 61.69, indicating that the coastal groundwater quality in Fujian Province was better than in Zhejiang Province. The results of the study revealed the impact of SWI and anthropogenic activity on groundwater in the southern coastal zone of China and will be valuable for sustainable groundwater resource management

Role of NLRP3 Inflammasome in the Progression of NAFLD to NASH

Nonalcoholic fatty liver disease (NAFLD) has been recognized as a major public health problem worldwide. Nonalcoholic steatohepatitis (NASH) is an advanced form of NAFLD that may progress to cirrhosis and hepatocellular carcinoma. The pathogenesis of disease progression from NAFLD to NASH has not been fully understood. Immunological mechanisms that have been increasingly recognized in the disease progression include defects in innate immunity, adaptive immunity, Toll-like receptor (TLR) signaling, and gut-liver axis. The NLRP3 inflammasome is an intracellular multiprotein complex involved in the production of mature interleukin 1-beta (IL-1β) and induces metabolic inflammation. NLRP3 inflammasome has been recently demonstrated to play a crucial role in the progression of NASH. This review highlights the recent findings linking NLRP3 inflammasome to the progression of NASH

<i>Bacillus paralicheniformis</i> RP01 Enhances the Expression of Growth-Related Genes in Cotton and Promotes Plant Growth by Altering Microbiota inside and outside the Root

Plant growth-promoting bacteria (PGPB) can promote plant growth in various ways, allowing PGPB to replace chemical fertilizers to avoid environmental pollution. PGPB is also used for bioremediation and in plant pathogen control. The isolation and evaluation of PGPB are essential not only for practical applications, but also for basic research. Currently, the known PGPB strains are limited, and their functions are not fully understood. Therefore, the growth-promoting mechanism needs to be further explored and improved. The Bacillus paralicheniformis RP01 strain with beneficial growth-promoting activity was screened from the root surface of Brassica chinensis using a phosphate-solubilizing medium. RP01 inoculation significantly increased plant root length and brassinosteroid content and upregulated the expression of growth-related genes. Simultaneously, it increased the number of beneficial bacteria that promoted plant growth and reduced the number of detrimental bacteria. The genome annotation findings also revealed that RP01 possesses a variety of growth-promoting mechanisms and a tremendous growth-promoting potential. This study isolated a highly potential PGPB and elucidated its possible direct and indirect growth-promoting mechanisms. Our study results will help enrich the PGPB library and provide a reference for plant–microbe interactions

The analysis on the inversion of the seawater intrusion based on RS - A case study of Longkou City

Hydrosphere movement in coastal zone performs as salty and fresh water mutual function. The Longkou city coastal zone which moves in the humanity under the intervention, has initiated the large-scale sea water intrusion, and therefore was especially under severe circumstances since 1980s. Until the end of 1980s and the beginning of the 90's, the sea water intrusion zone has formed the belt which spread fast from several hundred meters to several thousand meters along the coastal zone of Longkou city. Taking the landsat TM images in 2000 as data sources, first we applied the principal components transformation and analysis to analyze the six TM wave bands, and then use the histogram equalizing to deal with them. We use the two-value approach to be possible to remove the villages and small towns, the path, the pond (fishpond), the vegetables greenhouses, the rivers, the sand very conveniently. We take wave band as the research band, TM3, TM4 and TM5, which passed through correlation coefficient confirmation. Using the principal components analysis method to determine vegetation degree of coverage, the bare land index and the green index, the humidity analyzed in turn as four factors of the sea water intrusion. Inversion model of sea water intrusion is build up with the four factors. Finally a case study on the Longkou city, the analysis is obtained that the results have a very good correlation with the field measurements, and in accordance with the extent of the intrusion is divided into four categories. &copy; 2009 Copyright SPIE - The International Society for Optical Engineering

Tidal effects on groundwater level in coastal region under human disturbance

2278-2286Seawater intrusion has become a worldwide environmental alarming problem with global warming and sea level changes. A series of achievements have been made during last several decades, but the role of tidal effect in seawater intrusion has not yet been revealed, especially under the human disturbance. In this paper, cross-spectral and autocorrelation analysis were performed to identify the periodic relationship between the groundwater level and tidal level in a typical coastal area. After eliminating the long-term trend, Fourier transform and inverse Fourier transform were performed on the groundwater level data to extracted 0.040-0.085 frequency. Weconcluded that in the coastal region which is strongly affected by human interference, this is a effective approach to identify the tidal effects on groundwater level from other factors, especially human disturbance

Sedimentary Environment Analysis by Grain-Size Data Based on Mini Batch K-Means Algorithm

During the last several decades, researchers have made significant advances in sedimentary environment interpretation of grain-size analysis, but these improvements have often depended on the subjective experience of the researcher and were usually combined with other methods. Currently, researchers have been using a larger number of data mining and knowledge discovering methods to explore the potential relationships in sediment grain-size analysis. In this paper, we will apply bipartite graph theory to construct a Sample/Grain-Size network model and then construct a Sample network model projected from this bipartite network. Furthermore, we will use the Mini Batch K-means algorithm with the most appropriate parameters (reassignment ratio ϵ=0.025 and mini batch = 25) to cluster the sediment samples. We will use four representative evaluation indices to verify the precision of the clustering result. Simulation results demonstrate that this algorithm can divide the Sample network into three sedimentary categorical clusters: marine, fluvial, and lacustrine. According to the results of previous studies obtained from a variety of indices, the precision of experimental results about sediment grain-size category is up to 0.92254367, a fact which shows that this method of analyzing sedimentary environment by grain size is extremely effective and accurate