Search

In order to clarify the suction characteristics of unsaturated clay under different conditions of water and salt, taking soil in western Jilin province, China as the research object, the suctions (matrix suction and osmotic suction) of samples with different water content, salt type, and salt content were determined by filter paper method. The results indicate that salt type and content have insignificant influence on the matrix suction. With the increase of water content, the matrix suction decreases at different rates in different suction regimes. When water content is constant, the osmotic suction increases with the increase of salt content, and under the condition of a constant salt content, the osmotic suction first increases and then decreases with the increase of ion concentration of the pore water, and can reach tens of MPa. The concept of suction equilibrium water content is proposed. When water content of sample is higher than this value, the magnitude of osmotic suction will always be greater than that of matrix suction. This indicates the necessity to consider osmotic suction in the presence or change of salt in soil. The applicability of the traditional models of matrix suction and osmotic suction in the full suction range of clay is discussed, and it is found that the traditional models cannot make a full explanation to the variation in suction. Based on the experimental data, an improved van Genuchten matrix suction model and an osmotic suction model, transformed by the Planck blackbody radiation formula, are proposed. [ABSTRACT FROM AUTHOR]

Guvermectin is a nucleoside metabolite produced by the fermentation of Streptomyces hygroscopicus. It shows antibacterial and antitumor activities and has often been used as a plant growth regulator to promote the growth of crops. In this paper, the adsorption and degradation behavior of guvermectin in soil was investigated to evaluate its environmental safety. The adsorption of guvermectin in soil was consistent with the Freundlich isotherm model, and Freundlich adsorption coefficients (KF-ads) obtained from the model were low. The soil organic matter content was significantly and positively correlated with KF-ads. The effects of surfactant, humic acid, and biochar on the adsorption of guvermectin were studied using Jilin soil. The amount of guvermectin sorbed by the soil decreased with the addition of surfactant. By contrast, the amount adsorbed gradually increased as the amount of humic acid increased. Soil adsorption test with biochar revealed that biochar can efficiently sorb guvermectin. The half-life (t0.5) of guvermectin in soil under aerobic degradation and standing water anaerobic degradation conditions ranged from 2.84 to 7.29 days and from 8.21 to 13.70 days, respectively. The adsorption and degradation tests of guvermectin in soil revealed that pollution by guvermectin is not a major risk to soil because it is not easily adsorbed, it is highly mobile, and it can be easily degraded. [ABSTRACT FROM AUTHOR]

The rapid economic development and climate change have accelerated the changes in China's food production and have a potential impact on food security. In this paper, the grain sown area from 2001 to 2019 was selected to analyze the spatio-temporal evolution and driving factors of China's grain production through spatial autocorrelation analysis and geographically weighted regression. Our findings were as follows: (1) From the perspective of time characteristics, China's grain production from 2001 to 2019 experienced four stages, rapid decline, rapid growth, steady growth, and slow decline, although with an overall upward trend. (2) From the perspective of spatial characteristics, the overall spatial pattern had a significant positive correlation. The high values were mainly concentrated in Shandong, Anhui, and Jilin and moved to the northeast China as time went on. (3) In terms of influencing factors, the positive impact of agricultural labor force on the grain production gradually decreased, showing a decreasing trend from southwest to northeast. The promotion of agricultural mechanization on the grain production increased year by year, with the spatial distribution characteristics of high in the northeast and low in the southwest. Besides, the coefficient of water resources endowment was negative, showing a spatial distribution pattern of high north and low south. [ABSTRACT FROM AUTHOR]

Cross-hole radar is a method for geophysical exploration of geological conditions between two holes that can meet the need for refined detection of fractures. Full waveform inversion and reverse time migration are usually used in geophysical data processing and imaging. Full waveform inversion can invert the high-resolution relative permittivity image of the underground using the full-amplitude and phase information of the radar wave. Reverse time migration can migrate each reflection point in the radar record to its original position, thereby reflecting the real location of the underground interface. In this paper, we combined these two methods to achieve the purpose of refined detection of cross-hole radar for fractures in the tunnel side wall. Through several numerical simulation examples, we found that when there is a certain degree of electrical difference between the fractures and the surrounding rock, full waveform inversion can accurately reflect the distribution of the fractures and the relative permittivity value. Reverse time migration is more prominent in the description of the low-angle fractures interface, which facilitates the accurate division of the fracture. The combination approach of the two methods can accurately reflect the information of fractures in the wall, but the imaging effect for high-angle fractures is not ideal. The engineering data processing results of the cross-hole radar measured on the tunnel side wall of the Yinsong, Jilin, China prove the reliability of the method. [ABSTRACT FROM AUTHOR]

To promote the harmonious development of human and water resources, the scarcity and ecological value of water resources should be considered in water resource allocation. In this paper, synergetic theory was applied to the process of water resource allocation, and we constructed a synergetic theory-based water resource allocation model by investigating the synergetic principle of each link of water resource allocation. The objective equation was established for determining the optimal comprehensive benefit of the composite system. Multidimensional constraint conditions were constructed from the perspective of the social benefit, economic benefit and ecological benefit of water supply, and balance equations were established. Order parameters were selected for the social, economic and ecological subsystems, and the order degrees of the three subsystems and the synergetic degrees of allocation schemes were calculated by using the fuzzy mathematics method to provide a basis for the recommendation of an optimal scheme. Finally, we proposed a multicycle iterative algorithm to realize the overall objective of "harmonious development between humans and water resources", which provides an effective calculation tool for water resource synergetic allocation. This model was applied in Jilin, and an optimal scheme was recommended on the basis of a synergetic degree analysis, which shows that the water supply of conventional water sources will be saved by an increase in the reclaimed water supply. In addition, after the implementation of an external diversion project by 2030, the amount of groundwater withdrawal will be gradually reduced, and the water deficit rate will be significantly reduced. [ABSTRACT FROM AUTHOR]

The Jilin H5 chondrite, the largest known stony meteorite in the world, with its No.1 fragment weighing 1770 kg. It contains submillimeter- to centimeter-sized FeNi metal particles/nodules. Our optical microscopic and electron microprobe analyses revealed that the formation of metal nodules in this meteorite is a complex and long-term process, The early stage is the thermal diffusion-caused migration and concentration of dispersed metallic material along fractures to form root-hair shaped metal grains during thermal metamorphism of this meteorite. The later two collision events experienced by this meteorite led to the further migration and aggregation of metallic material into the shock-produced cracks and openings to form larger-sized metal grains. The shock-produced shear movement and frictional heating occurred in this meteorite greatly enhanced the migration and aggregation of metallic material to form the large-sized nodules. It was revealed that the metal nodule formation process in the Jilin H5 chondrite might perform in the solid or subsolidus state, and neither melting of chondritic metal grains nor shock-induced vaporization of bulk chondrite material are related with this process. [ABSTRACT FROM AUTHOR]

China features the second largest irrigation area in the world. Several modeling studies on a global scale have shown the irrigation impact in China, but no direct observational evidence has been reported. In this paper, we evaluated the impact of irrigation on temperature in Jilin province, China, using meteorological and satellite observations. The results show that the temperature difference between highly and lightly irrigated sites is statistically significant and highly correlated to the effective irrigation area and crop sown area over the past 53 years. The magnitude of the difference in maximum air temperature was almost twice that of the difference in minimum air temperature. The linear regression coefficient of the time series difference in maximum air temperature was more than three times that of the minimum air temperature. Moreover, both meteorological and satellite observations show that the temperature difference is amplified during drier years. The difference in the magnitude of daytime land surface temperature (LST), between areas with irrigation percentages of more than 50 and less than 50, is as high as 2.7 K during the driest year. Overall, this study may provide evidence that an irrigation cooling effect exists in China. [ABSTRACT FROM AUTHOR]

Understanding and prediction of mercury (Hg) phytoavailability in vegetable–soil systems is essential for controlling food chain contamination and safe vegetable production as Hg-contaminated soils pose a serious threat to human health. In this study, four typical Chinese soils (Heilongjiang, Chongqing, Yunnan, and Jilin) with varied physicochemical properties were spiked with HgCl2 to grow sweet pepper (Capsicum annuum L.) in a pot experiment under greenhouse condition. The chemical fractionation revealed a significant decrease in exchangeable Hg, while an increase in organically bound Hg in the rhizosphere soil (RS) compared to bulk soil (BS). This observation strongly highlights the vital role of organic matter on the rhizospheric Hg transformation irrespective of contamination levels and soil properties. Stepwise multiple linear regression (SMLR) analysis between Hg concentration in plants, Hg fractions in RS and BS, and soil properties showed that Hg in plant parts was significantly influenced by soil total Hg (THg) (R2 = 0.90), soil clay (R2 = 0.99), amorphous manganese oxides (amorphous Mn) (R2 = 0.97), amorphous iron oxides (amorphous Fe) (R2 = 0.70), and available Hg (R2 = 0.97) in BS. Nevertheless, in the case of RS, Hg accumulation in plants was affected by soil THg (R2 = 0.99), amorphous Mn (R2 = 0.97), amorphous Fe oxides (R2 = 0.66), soil pH, and organically bound Hg fraction (R2 = 0.96). Among all the evaluated soils (n = 04), metal (mercury) concentration in terms of plant uptake was reported highest in the Jilin soil. Based on SMLR analysis, the results suggested that the phytoavailability of Hg was mainly determined by THg and metal oxides regardless of the rhizospheric effect. These findings facilitate the estimation of Hg phytoavailability and ecological risk that may exist from Hg-contaminated areas where pepper is the dominant vegetable. [ABSTRACT FROM AUTHOR]

Typhoons usually bring natural disasters and economic losses. Satellite-based vegetation monitoring approaches largely improve our understanding of monitoring and assessing the area damaged by typhoons at high temporal and spatial scales, but it is still unclear which approach could achieve a greater robustness in assessing typhoon damages. From August 27 to September 8, 2020, three typhoons of Bavi, Maysak, and Haishen successively passed through the Northeast China, covering Liaoning, Jilin, and Heilongjiang provinces, and caused great damages to local vegetation and crops. Here, we employed two top-recognized approaches, i.e., the Normalized Difference Infrared Index (NDII) and the Disturbance Index (DI) derived from the moderate-resolution imaging spectroradiometer, to assess impacts three typhoons of Northeast China on the local vegetation and crops. With the help of Google Earth high-resolution images, this study demonstrated that the DI-based assessment gave a more accurate performance with an overall accuracy of 83% compared with NDII in typhoon-induced damages. DI was therefore used for spatial monitoring and assessment of three typhoon impacts. The DI-based results revealed that the damaged area of vegetation and crops in Northeast China was over 1.24 × 105 km2, including croplands, forests, and grasslands with the damaged area of 4.74 × 104 km2 (38.23% of total damaged area), 3.41 × 104 km2 (27.5%), and 0.12 × 104 km2 (0.97%), respectively. The damaged proportions were 14.13%, 13.19%, and 3.11% accounting for croplands, forests, and grasslands, respectively, of entire Northeast China. This study proves that DI-based vegetation damage assessment has more potential in large-scale monitoring of typhoon damages. [ABSTRACT FROM AUTHOR]

The Mesozoic granodiorite and their diorite enclaves in the Shulan area have been investigated to understand the petrographic characteristics and elemental geochemistry and to further interpret the petrogenesis and paleotectonic environment. The petrography, mineral component, zircon U-Pb age, and major and trace element contents of 9 granodiorite host rock samples and 9 diorite enclave samples were analyzed. Results show host rock and the enclave both present of medium-fine subhedral and porphyritic. The main rock-forming minerals of host rocks are plagioclase (57–60%), quartz (25–30%), and K-feldspar (6–13%), whereas the main rock-forming minerals of enclaves are plagioclase (65–83%), amphibole (3–20%), and biotite (5–25%). Zircon U-Pb dating results show that the weighted-mean 206Pb/238U ages of the granodiorite host rock and the diorite enclave are 168.1 ± 1.6 Ma and 181.0 ± 1.0 Ma, respectively. The SiO2 contents of the host rocks and enclaves are 61.95–64.86% and 51.12–59.32%, respectively. Their K2O/Na2O ratios are 0.51–1.24 and 0.41–1.02; aluminum saturation index A/CNK [Al2O3/(CaO + Na2O + K2O) molar ratio] are between 0.80–1.14 and 0.70–0.98 and A/NK [Al2O3/(Na2O + K2O) molar ratio] are 1.48–1.97 and 1.47–2.11, indicating a medium-high-K calc-alkaline series and a metaluminous series. The chondrite-normalized rare earth element (REE) patterns of both host rock and enclave samples show a right-dip model, but the Eu ratios of the host rock samples show weak negative anomalies, whereas the Eu ratios of the enclave samples show distinctive negative anomalies. The δEu [δEu = EuN/sqrt(SmN × GdN)] averages of both host rock and enclave samples are 0.75 and 0.63, respectively. The primary mantle normalized trace element patterns shows the enrichment of Rb, Th, U, La, Zr, Hf and Li and the depletion of Nb and Sm in the granodiorite host rocks, whereas enriched Rb, U, La, Pr, Nd, Zr, Hf, and Li and depleting Ba, Nb, Sr, Sm, and Eu are presented in the diorite enclaves. The REE, trace element patterns and the other geochemical indices indicate both granodiorite and diorite were derived from partial melting of pre-existent basaltic materials with a minor contribution of mantle materials. Host rocks and enclaves were formed in the same subduction-related paleotectonic environment, but in different stages of magma evolution. The subduction triggered the delamination of the lithosphere, causing upwelling of the asthenosphere and partial melting of the crust, forming the magmatic precursors of both kinds of rocks. [ABSTRACT FROM AUTHOR]

Chagan Lake is located in the high-fluorine area of western Jilin, with high fluoride content in surface water, soil, and groundwater around it. Due to its unique topography and hydrogeological conditions, Chagan Lake collects surrounding water and is closely connected with groundwater. The complex surrounding water not only affects the groundwater quality through Chagan Lake, but also affects groundwater through the infiltration of vadose zone. In order to further study the characteristics of the migration of F− in the soil around Chagan Lake along with water flow in the vadose zone and its impact on groundwater, soil column experiments were carried out using soil collected in the field, combined with HYDRUS-1D to simulate the migration characteristics of F−. The model was verified by measured data, the sensitivity of each parameter was analyzed by the single-factor disturbance method, and the effect of F− on groundwater was simulated and predicted. The results showed that (1) the soil column experiment was carried out using transport solutions of different pH value. The time required for F− to penetrate the soil column under alkaline conditions was shorter, and the HYDRUS model used has a high degree of fitting. (2) The single-factor disturbance method is used to analyze the sensitivity of the parameters. The parameters that have a greater impact on the migration of fluoride ions in the soil are saturated hydraulic conductivity, adsorption coefficient, and soil bulk density. (3) In the prediction scenario, due to the adsorption and interception of the vadose zone, as the depth increases, the time it takes for F− to accumulate is also longer. The groundwater around Chagan Lake is relatively shallow, and surface F− in alkaline environment reaches the underground aquifer within 2 days. The F− concentration in the groundwater reaches its maximum before the end of the irrigation period. In neutral environment, the F− concentration in groundwater did not reach the maximum before the end of the irrigation period. [ABSTRACT FROM AUTHOR]

The spatial variation of forest soil nutrients influences the species composition, distribution and diversity of forest plants, because soil nutrients are the most important environmental factors limiting the growth and survival of plants. We analyzed the effect of the spatial heterogeneity of soil nutrients on understory vegetation diversity in broadleaved-Korean pine forest, which had been undergone cutting disturbance. The results are of great significance in the sustainable management of the broadleaved-Korean pine forest and understanding the mechanism of correlation between heterogeneity and diversity. We sampled four plots of broadleaved-Korean pine forest in Jiaohe Forestry Bureau in Jilin province, China. Plot A, a control, was unlogged broadleaved-Korean pine forest. In plot B, C and D, forest was cut at 20%, 35% and 55% of the intensity in 2011. Cutting intensity influenced significantly on total nitrogen (TN), total phosphorous (TP), pH, soil organic matter (SOM), nitrate nitrogen (NN) and ammoniacal nitrogen except total potassium (p < 0.05). The values of TN, TP, pH and SOM showed that their quantities could decrease as cutting intensity increased. Species richness and diversity index of woody plants could increase in proportion to the cutting intensity, but species richness and diversity index of herbaceous plants might tend to decrease in early spring and summer. Coefficient of variation of TN, TP, SOM and NN could have either a positive or negative correlation with α-diversity indices of woody and herbaceous plants, while the other soil nutrient indices could have no correlation with diversity indices. [ABSTRACT FROM AUTHOR]

This work describes the characterization and genome annotation of Salmonella phage vB_SalM_8-19 (referred to as 8-19) isolated from sewage samples collected in a pig farm in Jilin, China. This phage was capable of infecting 60% Salmonella strains in our lab stock. The genome of phage 8-19 is composed of linear double-stranded DNA that is 52,648 bp in length with a G + C content of 46.02%; containing 74 ORFs and no tRNA genes. In October 2019, phylogenetic analyses indicated that phage 8-19 might belong to a novel cluster among the other similar phages which have not been specifically classified within some new genus in family Myoviridae. Recently, the International Committee on Taxonomy of Viruses (ICTV) defined phage 8-19 and its related phages as genus Rosemountvirus, family Myoviridae. This new genus, known as Rosemountvirus, is rarely reported in the literature. [ABSTRACT FROM AUTHOR]

The Late Triassic Tianqiaoling flora is well-known in China, and its discovery has changed our understanding of Chinese Late Triassic phytogeographical divisions. More broadly, this flora has great significance for the study of phytogeography in East Asia during this time. However, the previous dating of this flora was only evidenced by plant fossils and stratigraphic correlation, and the accurate dating has still not been achieved. In this study, rhyolite samples were collected from the bottom of the Tianqiaoling Formation, which is conformally contacted the Tianqiaoling flora-bearing beds. The results of new U-Pb dating gave ages for the rhyolites of 212.8±2.5 Ma, indicating the end of Malugou Formation and initial Tianqiaoling Formation in deposition occurred in the late Norian (~227–208.5 Ma), which is contemporaneous with the peak of the Tianqiaoling flora in development. Our radiometric dating results are basically consistent with paleobiological evidence. The new age provides a key anchor point for regional stratigraphic correlation of the Tianqiaoling flora with its related Late Triassic floras, and contribute to a better understanding of the geology and phytogeography in the East Asia, particularly in the "triangle region" covering the eastern Jilin (China), South Primorye (Russia) and Southwest Japan, during the Late Triassic. [ABSTRACT FROM AUTHOR]

Sufficient water is essential for maintaining rice production yields, but precipitation and ground water generally do not meet the requirements for rice growth. Irrigation is therefore necessary and the quantity of irrigation water requirement (IWR) is also highly dependent on climatic alterations. We utilized an ensemble of 20 fine-resolution downscaled global climate models to characterize the future dynamics of IWR across Northeast China, under two representative concentration pathway scenarios (RCP4.5 and RCP8.5). Crop evapotranspiration was a critical factor in IWR determinations and was estimated through the Hargreaves model. The model was recalibrated to optimize its performance and this resulted in normalized root mean squared errors of < 10%. Based on reliable crop evapotranspiration and effective precipitation data in baseline (1976–2005) and future periods (2036–2065 and 2070–2099), IWR decreased from southwestern Heilongjiang and western Jilin to the southeastern and northeastern areas. The IWR displayed a general increasing trend but overall the tendency decreased from west to east. The western areas were exposed to higher magnitudes of IWR increases, indicating that the water deficit for rice would be more severe in these regions. IWR levels increased with time slice under RCP8.5 relative to RCP4.5. The predicted IWR changes in future periods were greatest for Heilongjiang, followed by Jilin and Liaoning. In addition, Heilongjiang was predicted to have the most stable IWR in the future. These predictions of IWR dynamics highlight sensitive areas prone to water deficits and can serve as guides for specific irrigation schedules in the different rice growing regions across Northeast China. [ABSTRACT FROM AUTHOR]

This study collected and compiled statistical data on atmospheric pollution in Jilin City, China during 2013–2014, using models and methods to calculate the source proportion of PM2.5 emitted by various sources. The statistical activity levels and emission factors of various pollution sources were found to be key parameters for obtaining the total amount of PM2.5 in the exhaust gas emitted from all types of pollution sources using an emissions model. In this study, relevant data were collected by the top-down method, and pollutant emission was calculated by the emission factor method to establish the PM2.5 pollution emission inventory of Jilin City. The source apportionment was calculated using the Chemical Mass Balance (CMB) model. Industrial process source and fixed combustion source are the largest sources of PM2.5 emission from all sources, respectively. Among the two calculation results, the results of pollution emission inventory are more accurate. The PM2.5 emission inventory in Jilin was established and countermeasures were proposed focused on the coordinated control of air pollution and the prevention and control of industrial dust pollution sources, as well as environmental management and impact assessment. [ABSTRACT FROM AUTHOR]

Counterpart cooperation is a major innovative measure in China's strategy for revitalizing north-eastern China. While promoting economic progress, regional counterpart cooperation should also focus on low-carbon economy and sustainable development. Under the background of China's proposed innovative cooperation strategy, using a multi-regional input-output (MRIO) model and structural decomposition analysis (SDA), this study takes Jilin province and its counterpart Zhejiang province as an example and decomposes the change in carbon emission intensity (CEI), which is a widely used indicator to measure regional carbon emission performance. The decomposition spans the years 2007 to 2012, at the level of two provinces and departments. By comparing the factors that drive and inhibit CEI in the two provinces, it was found that the production technology effect in Jilin province primarily drove the growth in CEI, while in Zhejiang province, the opposite occurred. Second, the structural effects of agriculture and heavy industry in Jilin province accounted for the largest proportion of this change, and the pulling effect on the increase in CEI in Jilin was significantly higher than that in Zhejiang province. Third, the scale effect of agricultural demand in Zhejiang province was much higher than that in Jilin province, and the same trend was observed for the scale effect of heavy industrial exports. [ABSTRACT FROM AUTHOR]

We undertook U-Pb-Hf isotope testing of detrital zircons from Late Paleozoic sedimentary rocks in the Jilin Province, NE China, with the aim of constraining the tectonic evolution of eastern Central Asian Orogenic Belt. The age populations of the detrital zircons from the sandstone of the Jiefangcun Formation in the Songliao Block are ~2234, ~1782, ~1030–921, ~817, ~540, and ~381–254 Ma, whereas those of the zircons from the greywacke of the Permian Kedao Formation in the Songliao Block yield are ~2436, ~1905, ~1692, 1146–1170, ~554–498, and ~342–255 Ma. Combined Hf isotope characteristics, these ages reveal that: (1) rocks from the Jiefangcun and Kedao formations were deposited after 254 and 255 Ma, respectively; (2) these formations were sourced mainly from the Songliao Block and the Jiamus Terrane in the eastern CAOB and to a lesser amount, from the northern margin of the NCC; and (3) it appears that several remnants of ancient Precambrian basement occur adjacent to these Late Paleozoic strata that occur within the microcontinental blocks. Detrital zircons from the silty sandstone of the Miaoling Formation in the western margin of the Khanka Terrane yield peak age populations of 508–476, 463–396, and 348–258 Ma, having similar εHf(t) values to those obtained from zircons within the Jiamusi Terrane. These data indicate that (1) deposition of the Miaoling Formation in the western margin of the Khanka Terrane had started by 258 Ma, and (2) these sediments were sourced mainly from the Jiamusi Terrane and local magmatic rocks. The widespread occurrence of detrital zircons with ages of 480–550 Ma and positive εHf(t) values within the Late Paleozoic strata in the Songliao Block and the Jiamusi–Khanka Terrane, indicates that the amalgamation of these blocks took place during the middle stage of the Paleozoic, probably after the Silurian, prior to the Late Permian. [ABSTRACT FROM AUTHOR]

In May 2018, a bacterial tumor disease was observed on Populus koreana in Shuangyang county, Changchun city, Jilin Province. Based on physiological characteristics, Biolog and genetic sequences analysis, the bacterium was identified as Pseudomonas aeruginosa. The pathogenicity was verified with Koch's postulates. To our knowledge, this is the first report of tumor disease caused by P. aeruginosa on P. koreana. [ABSTRACT FROM AUTHOR]

Magmatic and metasomatic rock suites can be commonly found in active convergent margins as the suprasubduction zone mantle wedge is usually impregnated by melts and fluids. Here we present petrologic, whole-rock geochemical and zircon U-Pb and Lu-Hf data from metamorphic intermediate-mafic and ultramafic rocks in central Jilin Province, NE China, to constrain the Early Paleozoic tectonic evolution of the southeastern margin of the Xing'an-Mongolia Orogenic Belt. Lithologically, the meta-igneous rocks are composed of plagioclase-actinolite, meta-allgovite, tremolitized pyroxenite, and serpentinized peridotite. Geochronological results indicate that the protoliths of the meta-igneous rocks formed during the Early–Middle Ordovician (474–466 Ma). Geochemical features suggest that the rocks are calc-alkaline and transitional-series rocks relatively enriched in large-ion lithophile and light rare earth elements and depleted in high field strength and heavy rare earth elements, implying that they formed in a supra-subduction zone environment. Additionally, the protoliths of the plagioclase-actinolites, which display an affinity for sanukites, resulted from an equilibrium reaction between mantle peridotite and slab melts derived from the partial melting of subducting sediments during early-stage subduction; the meta-allgovite rocks were likely derived from a juvenile depleted lithospheric mantle that was metasomatized by subduction-related fluids; the ultramafic rocks are magmatic cumulates formed in a suprasubduction zone mantle wedge. Furthermore, the meta-allgovite rocks display both arc-like and MORB-like geochemical characteristics, suggesting an intra-continental back-arc basin setting. These features, combined with the presence of the abundance of zircon xenocrysts with Neoproterozoic–Paleozoic ages, as well as the results of previous studies, reflect that a small-scale and limited back-arc basin, which was related to the northward subduction of the Paleo-Asian oceanic plate, probably existed close to the Songnen-Zhangguangcai Range Massif during the Early–Middle Ordovician. [ABSTRACT FROM AUTHOR]

The early Precambrian basement of the North China Craton, China, records a complex history during the Neoarchean and Paleoproterozoic. Southern Jilin Province is one of the best regions to evaluate the early Precambrian crustal growth of the Eastern Block of the North China Craton. We herein present new zircon cathodoluminescence images, U-Pb dates, trace element and Lu-Hf isotope data for three late Neoarchean tonalitic-trondhjemitic-granodioritic (TTG) gneisses and one Paleoproterozoic mafic dyke from Tonghua region, southern Jilin Province. These results lent convincing support to the occurrence of multiple tectono-thermal events in southern Jilin Province during the Archean and Paleoproterozoic, and shed light on the formation and evolution of continental crust in the northeastern Eastern Block. Zircon LA-ICP-MS U-Pb isotopic analyses indicated three episodes of magmatism. Inherited (or captured) zircons with ages of ca. 2.6 Ga provided strong evidence for a pre-2.5 Ga magmatic event in this region. The second magmatic episode occurred at 2556-2522 Ma, as evidenced by extensive exposures of TTG gneisses. The third episode occurred at ca. 2200 Ma and is recorded by several mafic dykes that intruded the Archean TTG gneisses. Metamorphic zircons yielded consistent ages of 2493-2465 Ma, indicating a regional metamorphic event immediately after the late Neoarchean magmatism in southern Jilin Province. Zircon Hf isotope data of the TTG gneisses indicated that the main phase of crustal growth occurred in the late Neoarchean, with a minor input of Mesoarchean continental crustal materials. The combined geochronological, geochemical, and geological data suggested that the three episodes of crustal growth in the northeastern Eastern Block occurred at 2.8-2.7, 2.6-2.5, and 2.2 Ga. [ABSTRACT FROM AUTHOR]

Advance grouting is an important approach to reinforce the rock mass ahead of the tunnel face in TBM tunneling. To estimate the grouting result in TBM tunneling, a test method based on seismic ahead prospecting method was proposed. To check the grouting result, the seismic ahead prospecting was applied firstly to obtain the distribution and location of adverse geologies for grouting; Then, the geological conditions was estimated again after grouting; By studying the characteristics of reflections and velocity distributions, the grouting result could be checked. Numerical simulations prove the availability: Wave field snapshots indicate the energy of reflected waves reduces after grouting; Migration results indicate that the reflections reduce or disappear after advance grouting, as well as the estimated velocity increases. Moreover, the method was successfully applied in the diversion tunnel of the water supply project from Songhua River, which reveals the grouting result well and provides important geological guidance for construction. [ABSTRACT FROM AUTHOR]

The assessment of urban water shortage risk is crucial to the development of management strategies that enable a more systematic allocation of water resources and effectively reduce societal losses. The present work proposes a comprehensive approach to the thorough evaluation of water shortage risk in an urban basin. We focus on a case study in Jilin City, demonstrating the suitability of the proposed method. The development and utilization of hydric resources in Jilin City is both evaluated and simulated using the MIKE BASIN model, involving hydrological data from 1956 to 2010. Furthermore, this investigation provides a comparison between measured and analog quantity results during the period 2001-2010, yielding an acceptable average relative error of 4.478 %. Five indicators, namely, hazard rate, restorability, vulnerability, recurrence period, and risk level are investigated with the purpose of organizing the assessment system prior to mapping the level of water shortage risk with the SVM model. The data calculated from both the MIKE BASIN model and the emergency conditions are used to formulate five indicators of water shortage assessment. Finally, the level of water shortage risk is determined for six sub-basins in Jilin City. Several schemes are capable of improving the water supply and alleviating the shortage conditions. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate bacterial communities between rhizosphere and non-rhizosphere soils of the wild medicinal plant Rumex patientia of Jilin, China, small subunit rRNAs (16S rDNA) from soil metagenome were amplified by polymerase chain reaction using primers specific to the domain bacteria and analysed by cloning and sequencing. The relative proportion of bacterial communities in rhizosphere soils was similar to non-rhizosphere soils in five phylogenetic groups (Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi and Planctomycetes). But there were differences in five other phylogenetic groups (Firmicutes, Bacteroidetes, Gemmatimonadetes, Verrucomicrobia and Unclassified bacteria). Over 97.24 % of the sequenced clones were found to be unique to rhizosphere and non-rhizosphere soils, while 2.76 % were shared by both of them. Our results indicate that there are differences in the composition and proportion of bacterial communities between rhizosphere and non-rhizosphere soils. Furthermore, the unique bacterial clones between rhizosphere and non-rhizosphere soils of the wild medicinal plant R. patientia have obvious differences. [ABSTRACT FROM AUTHOR]