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Wu C.,Shaanxi Normal University | Zhang Y.,Shaanxi Normal University | Chai L.,Chang'an University | Chai L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Wang H.,Shaanxi Normal University
Chemosphere | Year: 2017

Chinese toad (Bufo gargarizans) were exposed to different concentrations of cadmium (5, 50, 100, 200 and 500 μg Cd L−1) from Gosner stage 3–42. Metamorphosis rate, body weight, total length and body length were measured. Histological alterations in thyroid gland and liver were examined. Changes in hepatocyte were also examined using Transmission electron microscopic. In addition, the mRNA expression of several genes involved in lipid metabolism, oxidative stress and thyroid hormones signaling pathways were also measured. Our results showed that 200 and 500 μg Cd L−1 decreased the metamorphosis rate and inhibited the body size of B. gargarizans larvae at G42. Moreover, histological examinations have clearly exhibited that cadmium caused liver damage. Ultrastructural examination revealed lipid accumulation and abnormal mitochondria. Exposure to 200 and 500 μg Cd L−1 significantly up-regulated mRNA expression of D2, SOD, GPx, ACC and FAE, but down-regulated mRNA expression of TRα, TRβ, PPARα, ACOX, CPT and SCP. However, low Cd concentration (5, 50 and 100) exposure did not cause any effect in genes expression. Thus, we conclude that high Cd concentrations could affect the normal processes of lipid metabolism though increasing lipid synthesis and reducing the ability of fatty acid β-oxidation, and disturb thyroid hormone pathways in liver, and induced oxidative stress. In addition, lipid metabolism might be regulated by THs. To our knowledge, the present study is the first to report the influence of cadmium on hepatic lipid metabolism in B. gargarizans and will greatly provide new insights into cadmium hepatotoxicity in amphibian. © 2017 Elsevier Ltd


Liu X.,Chang'an University | Liu X.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | He B.,Gansu Academy of Agricultural science | Yi X.,Chang'an University | Han F.,Dongguan Water Conservancy Survey and Design Institute Co.
Environmental Earth Sciences | Year: 2016

The soil water supply is the main limiting factor for dryland crop production on the Loess Plateau in China. Local farmers have been looking for tactics to interfere with natural hydrologic processes and to conserve soil water in dry seasons. Recently, plastic film mulching has been widely used by local farms. Moreover, mulching no longer occurs before planting, instead, it is done earlier, and thus crop yields increase. Therefore, soil water hydrologic processes for fields mulched entirely with plastic film mulch require better understanding. Field experiments were conducted from October 2009 to September 2010, 2011, and 2013 to evaluate the soil water dynamics and hydrologic process in winter wheat, maize, and potato fields with plastic film mulching. The soil moisture for depths of 0–100 cm in 2010–2011 and 0–200 cm in 2013 was measured at every 20-cm depth interval during the growth period from sowing to harvesting in all of the treatments. The results showed that the soil water distribution of a plastic film-mulched field is significantly different from that of an unmulched field. The soil water of the mulched field presented an obvious inverted S-trend at depths of 0–60 cm during the growth season. During the dry season (winter and spring), under conditions of high surface evaporation and no effective rainfall, changes in the boundary conditions of the vapor migration hydrologic process between the soil and atmosphere by the mulched treatments led to an obvious increase in the soil water with wheat increasing by 3.45 (cm3/cm3) at depths of 0–20 cm and maize and potato increasing by 0.04–6.04 (cm3/cm3) at depths of 0–80 cm. This condition increased the available water to guarantee the crops’ water demand at the dry seedling stage for maize and the revival stage for wheat against the threat of seasonal drought and ensured a higher crop yield. © 2016, Springer-Verlag Berlin Heidelberg.


Zhang H.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Zhang H.,Chang'an University | Singh V.P.,Texas A&M University | Sun D.,Chang'an University | And 2 more authors.
International Journal of Water Resources Development | Year: 2016

This study performed a quantitative evaluation of the impact of water-saving irrigation on the groundwater regime in the Hebei Province plains area. In this work, the change in groundwater regime and the contributions of precipitation and water-saving irrigation development were investigated. The results indicate that the groundwater overdraft has been mitigated to some extent, mainly due to changes in precipitation and the implementation of water-saving irrigation, with contributions of 64.3% and 35.7%, respectively, when considering only these two factors. Water-saving irrigation is accepted as an important means for reducing groundwater depletion, but should be used in conjunction with other measures. © 2016 Informa UK Limited, trading as Taylor & Francis Group


Wang M.,Shaanxi Normal University | Chai L.,Chang'an University | Chai L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Zhao H.,Shaanxi Normal University | And 2 more authors.
Chemosphere | Year: 2015

Chinese toad (Bufo gargarizans) tadpoles were exposed to nitrate (10, 50 and 100mg/L NO3-N) from the beginning of the larval period through metamorphic climax. We examined the effects of chronic nitrate exposure on metamorphosis, mortality, body size and thyroid gland. In addition, thyroid hormone (TH) levels, type II iodothyronine deiodinase (Dio2) and type III iodothyronine deiodinase (Dio3) mRNA levels were also measured to assess disruption of TH synthesis. Results showed that significant metamorphic delay and mortality increased were caused in larvae exposed to 100mg/L NO3-N. The larvae exposed to 100mg/L NO3-N clearly exhibited a greater reduction in thyroxine (T4) and 3,5,3'-triiodothyronine (T3) levels. Moreover, treatment with NO3-N induced down-regulation of Dio2 mRNA levels and up-regulation of Dio3 mRNA levels, reflecting the disruption of thyroid endocrine. It seems that increased mass and body size may be correlated with prolonged metamorphosis. Interestingly, we observed an exception that exposure to 100mg/L NO3-N did not exhibit remarkable alterations of thyroid gland size. Compared with control groups, 100mg/L NO3-N caused partial colloid depletion in the thyroid gland follicles. These results suggest that nitrate can act as a chemical stressor inducing retardation in development and metamorphosis. Therefore, we concluded that the presence of high concentrations nitrate can influence the growth, decline the survival, impair TH synthesis and induce metamorphosis retardation of B. gargarizans larvae. © 2015 Elsevier Ltd.


Gong Y.,Beijing University of Technology | Gong Y.,Ohio State University | Zhang Y.,Beijing University of Technology | Lan S.,Beijing University of Technology | And 2 more authors.
Water Resources Management | Year: 2016

Accurate and reliable prediction of groundwater level is essential for water resource development and management. This study was carried out to test the validity of three nonlinear time-series intelligence models, artificial neural networks (ANN), support vector machines (SVM) and adaptive neuro fuzzy inference system (ANFIS) in the prediction of the groundwater level when taking the interaction between surface water and groundwater into consideration. These three models were developed and applied for two wells near Lake Okeechobee in Florida, United States. 10 years data-sets including hydrological parameters such as precipitation (P), temperature (T), past groundwater level (G) and lake level (L) were used as input data to forecast groundwater level. Five quantitative standard statistical performance evaluation measures, correlation coefficient (R), normalized mean square error (NMSE), root mean squared error (RMSE), Nash-Sutcliffe efficiency coefficient (NS) and Akaike information criteria (AIC), were employed to evaluate the performances of these models. The conclusions achieved from this research would be beneficial to the water resources management, it proved the necessity and effect of considering the surface water-groundwater interaction in the prediction of groundwater level. These three models were proved applicable to the prediction of groundwater level one, two and three months ahead for the area that is close to the surface water, for example, the lake area. The models using P, T, G and L achieved better prediction result than that using P, T and G only. At the same time, results from ANFIS and SVM models were more accurate than that from ANN model. © 2015, Springer Science+Business Media Dordrecht.


Wang Y.L.,Chang'an University | Wang Y.L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education
Applied Mechanics and Materials | Year: 2014

The dynamic adsorption of atmospheric trace Kr and Xe, which discharged from the dynamic adsorption experimental equipment at room temperature, on selected adsorbents VACF and GCAC were studied. The stable isotope 84Kr and 129Xe were designated as tracing indicator and determined by ICP-MS. The results suggest that: (1)under the experimental conditions, which included that the column length was 1m, the flow was 2m3/h, and the maximum uniform loading density of VACF column and GCAC column was respectively 0.0165 g/cm3and 0.459 g/cm3, the DACwhich indicated the adsorption capacity of Kr and Xe adsorbed on VACF at room temperature was about 3.08×104 cm3/g, the DAC which indicated the adsorption capacity of Kr and Xe adsorbed on GCAC at room temperature was about 5.55×103 cm3/g; (2) the air flow capacity couldn’t be promoted by simply increasing the column length of VACF or GCAC. For VACF adsorbent, although its DACwas superior to the GCAC’s, but when the length of VACF column was increased to 2m, the air flow resistance was ascended obviously, and the air flow capacity was descended substantially. However, because the cost-effectiveness of GCAC adsorbent was higher, the flow resistance of GCAC column was smaller and the controlling range of air flow was larger than VACF, all of these results show that the comprehensive performance of GCAC is better than VACF at present. © (2014) Trans Tech Publications, Switzerland.


Chen J.,Shaanxi Normal University | Chai L.,Chang'an University | Chai L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Zhao H.,Shaanxi Normal University | And 2 more authors.
Fluoride | Year: 2016

Chronic exposure to high fluoride ion levels (F) may lead to local tissue disturbances, known as fluorosis. The present study was conducted to determine the effects of sodium fluoride (NaF) on the growth, metamorphosis, and skeletal development in tadpoles of Rana chensinesis and Rana nigromaculata. The mortality, percentage of tadpoles completing metamorphosis, total length, body weight, and hindlimb length were determined. In addition, skeletal systems were investigated by using double staining methodology at Gosner stages 36, 42, and 46. The results showed that chronic exposure to 50 mg NaF/L significantly increased the mortality, inhibited metamorphosis, and delayed development in R. chensinesis and R. nigromaculata tadpoles. The NaF treatment also produced flexural tail malformations in R. chensinesis tadpoles but not in R. nigromaculata tadpoles, stimulated bone mineralization in R. chensinesis tadpoles, and retarded the deposition of calcium in R. nigromaculata tadpoles. In conclusion, our study suggests that fluoride may affect skeletal ossification differently in different frog species due to differences in sensitivity or the duration of the exposure. © 2016 The International Society for Fluoride Research Inc.


Qiao L.,Chang'an University | Qiao L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Dai M.,Shaanxi estate development service corporation | Li M.N.,Chang'an University | Li M.N.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education
Applied Mechanics and Materials | Year: 2014

Based on the analysis of the current state of water resources and utilization characters, the optimizing and allocating model of water resources in Yinchuan plain is established by multi-objective planning methodology. Systematic viewpoint runs throughout the whole modeling process. Furthermore, by employing the established model, the proper allocation of the industrial and agricultural water, the ecological environment water and integrated development of surface water and groundwater are discussed. The more reasonable water utilization structure is suggested. The water resource for agriculture is decreasing, while the water resource for people life, industry and ecologic environment are increasing. This change of water utilization is correspond to economic and social development trend. © (2013) Trans Tech Publications, Switzerland.


Wang C.,Shaanxi Normal University | Liang G.,Shaanxi Normal University | Chai L.,Chang'an University | Chai L.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Wang H.,Shaanxi Normal University
Aquatic Toxicology | Year: 2016

Chinese toad (Bufo gargarizans) tadpoles were exposed to copper (1, 6.4, 32 and 64μgL-1 copper) from the beginning of larval period through completion of metamorphosis. We examined the effects of chronic copper exposure on mortality, growth, time to metamorphosis, tail resorption time, body size at the metamorphic climax (Gs 42) and completion of metamorphosis (Gs 46) and thyroid gland histology. In addition, type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. Our result showed that 6.4-64μgL-1 copper concentration increased the mortality and inhibited the growth of B. gargarizans tadpoles. In addition, significant reduction in size at Gs 42 and a time delay to Gs 42 were observed at 6.4-64μgL-1 copper treatments. Moreover, histological examinations have clearly revealed that 64μgL-1 copper caused follicular cell hyperplasia in thyroid gland. According to real-time PCR results, exposure to 32 and 64μgL-1 copper significantly up-regulated mRNA expression of Dio3, but down-regulated mRNA expression of TRα and TRβ mRNA level. We concluded that copper delayed amphibian metamorphosis through changing mRNA expression of Dio3, TRα and TRβ, which suggests that copper might have the endocrine-disrupting effect. © 2015 Elsevier B.V.


Zhang H.,Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education | Zhang H.,Chang'an University | Singh V.P.,Texas A&M University | Zhang Q.,Sun Yat Sen University | And 2 more authors.
Environmental Earth Sciences | Year: 2016

The upper Yellow River basin is located in the new Silk Road economic belt. Fundamental to the healthy development of the Yellow River ecosystem and the security of water resources in the economic belt are the hydrological regime change that drives river ecosystem processes, or called ecological flow regimes (EFR). When developing a sustainable and ecofriendly Silk Road economic belt, the evaluation of the alteration of the EFR and an attribute analysis should receive great attention because they can provide decision makers with more information on ecological implications for balancing environmental and human water needs. The objective of this paper is to investigate the EFR variation at the Lanzhou gauge as the control section of the upper Yellow River basin. First, the paper addresses the macroscale EFR using ecoflow metrics (ecodeficit and ecosurplus), i.e., the multi-year trend of the annual and seasonal changes in ecological flow. Second, it evaluates microscale variations in EFR via the Yellow River ecohydrological index system and compares them with macroscale changes in EFR to verify their consistency. Third, it analyzes the attributes of EFR variation and determines the impact of the construction and operation of reservoirs on the variation. Results show that macro- and microscale EFR at the Lanzhou gauge have significant changes before and after the construction of reservoirs in the upper Yellow River basin, reaching a high degree of alteration. Reservoir construction and operation have been the major reason for the alteration of EFR in the past few decades, and the cascade reservoir regulation has more significantly affected the changes in EFR than has a single reservoir, placing the downstream fluvial ecological system under serious risk. This change should arouse considerable concern, particularly in the development of the new Silk Road economic belt. In addition, ecoflow metrics used for reflecting the macroscale change in this study are highly correlated with microscale indicators of EFR that are accepted in the upper Yellow River basin. This result implies that ecoflow metrics can mirror most ecological information from these microscale indicators and are suitable for the evaluation of alterations in hydrological processes at annual and seasonal timescales. © 2016, Springer-Verlag Berlin Heidelberg.

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