作者： 罗斯;李媛;雷鸣

期刊： 教育教学论坛,2023年(11):173-176 ISSN：1674-9324

作者机构： [罗斯; 李媛; 雷鸣] 湖南农业大学资源环境学院

关键词： 新农科;地方性农业院校;研究生;培养模式

摘要： 研究生是推动科技进步的新生力量，改革研究生培养模式，向社会输送符合当前农业发展所需的合格人才，是地方性农业院校研究生人才培养肩负的使命。在新农科建设背景下，调研分析当前地方性农业院校在研究生培养方面存在的深层次问题和不足，积极探索适应新时代、服务乡村振兴战略实施的农业科学类研究生培养模式，包括明确培养目标、完善课程体系、加强导师队伍建设、结合地方农业发展特色创造产学研融合共促的研究生培养模式，以期为完善和优化学校研究生培养体系、全面提升农业院校的综合素质与核心竞争力提供一定的理论参考。

语种： 中文

作者： Du, Yuhang;Zhou, Qiaoqiao;Peng, Zenghui;Peng, Fangcheng;Xi, Lianlian;...

期刊： FRONTIERS IN PLANT SCIENCE,2022年13:864316 ISSN：1664-462X

通讯作者： Li, Y.

作者机构： [Xi, Lianlian; Li, Youzhi; Peng, Fangcheng; Zhou, Qiaoqiao; Du, Yuhang; Peng, Zenghui] Hunan Agr Univ, Coll Resources & Environm, Changsha, Peoples R China.;[Xi, Lianlian; Li, Youzhi; Peng, Fangcheng; Zhou, Qiaoqiao; Du, Yuhang; Peng, Zenghui] Hunan Agr Univ, Hunan Prov Key Lab Rural Ecosyst Hlth Dongting Lak, Changsha, Peoples R China.

通讯机构： [Li, Y.] C;College of Resources and Environment, China

关键词： Triarrhena lutarioriparia;Phragmites australis;Competition intensity;interspecific competition;relative growth rate;Niche difference

摘要： The distribution range of plants is usually related to their competitiveness. The competitive ability between common widespread, which are generally considered to be invasive, and common endemic species, is still not very clear. Five plant communities were monitored in the field to compare the competitive abilities of widespread species, Phragmites australis, and endemic species, Triarrhena lutarioriparia, in the Dongting Lake wetlands. The ratios of individual numbers of T. lutarioriparia to P. australis per square meter were found to be 9:0, 14:1, 10:5, 7:6, and 0:11 in the five respective communities. A manipulation experiment was then performed with five planting modes (T. lutarioriparia: P. australis was 4:0, 3:1, 2:2, 1:3, and 0:4, respectively). Results from field monitoring showed that the two plant species exhibited similar decreased survival percentages during flooding. P. australis had higher aboveground biomass before the flooding and a higher relative elongation rate, whereas T. lutarioriparia had higher aboveground biomass after flooding and a higher relative growth rate (RGR). P. australis had a higher competitive ability than T. lutarioriparia before and after the flooding. The manipulation experiment revealed that P. australis had a higher survival percentage than T. lutarioriparia, with no differences in plant biomass, RGR, and the relative elongation rate between the two species. P. australis was found to have a higher competitive ability than T. lutarioriparia in the early growing stage and a lower competitive ability in the middle and later stages. The relative yield total in the field monitoring and manipulation experiment was 1, indicating that T. lutarioriparia and P. australis occupied different niches in the experimental conditions. It was concluded that, compared with T. lutarioriparia, P. australis has a higher competitive ability in submerged habitats and a lower competitive ability in the non-submerged habitat. The niche differences between the two species enabled their coexistence in the Dongting Lake wetlands with seasonal flooding.

语种： 英文

作者： Meng, Cen;Liu, Huanyao;Li, Yuyuan*;Wang, Yi;Li, Xi;...

期刊： Science of The Total Environment,2022年804:150055 ISSN：0048-9697

通讯作者： Li, Yuyuan

作者机构： [Wang, Yi; Zhang, Miaomiao; Li, Yuyuan; Wu, Jinshui; Gong, Dianlin; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.;[Wang, Yi; Zhang, Miaomiao; Li, Yuyuan; Wu, Jinshui; Gong, Dianlin; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Changsha Res Stn Agr & Environm Monitoring, Inst Subtrop Agr, Changsha 410125, Peoples R China.;[Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Xi; Meng, Cen; Shen, Jianlin] Univ Chinese Acad Sci, Beijing 10049, Peoples R China.;[Liu, Huanyao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Li, Yuyuan] 644 Second Yuanda Rd, Changsha 410125, Peoples R China.

通讯机构： [Li, Yuyuan] 6;644 Second Yuanda Rd, Changsha 410125, Peoples R China.

关键词： Headwater catchment;Land use;Legacy effect;NAPI;Phosphorus;Trend decomposition

摘要： Landscape composition and configuration determine the exchange of matter and energy among different landscape patches and may affect riverine phosphorus (P) exports derived from watershed legacy sources. However, a lack of understanding of landscape pattern effects on legacy P releases has yielded large uncertainties in mitigating watershed water quality using management practices or landscape planning. This study revealed the significance of legacy effect in the headwater catchments through the time-lag response of the long-term trend of river P exports to the change of net anthropogenic P input (NAPI). By constructing empirical statistical models that incorporated NAPI, hydroclimatic, terrain factors, soil chemical properties, and land use variables, the sources of annual riverine total phosphorus (TP) and dissolved inorganic phosphorus (DIP) exports were divided into current annual NAPI input and legacy sources inputs. The model estimations indicated that the contribution of legacy sources to riverine TP exports was 0.33-1.12 kg ha(-1) yr(-1) (50.7-82.8%), which was signifi-cantly higher than the contribution to DIP exports (0.18-0.49 kg ha(-1) yr(-1), 42.4-81.4%) in 2012-2017. Redundancy analysis (RDA) and variance partitioning analysis (VPA) methods were used to quantify the relative contribution of landscape patterns, soil P content, and terrain factors to legacy P releases. Results revealed that the relative contribution of the landscape composition and configuration to the total variations of legacy P releases was greater than that of the soil P and terrain factors. For different land use patches, a large area of woodland with a high aggregation degree and a large area of ponds with multiple net structures may significantly alleviate legacy P releases. In contrast, the legacy P releases were significantly positively associated with highly aggregated agricultural, tea plantation, and residential patches. This study provides theoretical support for strategies aiming to control legacy P from the perspective of landscape planning. (C) 2021 Elsevier B.V. All rights reserved.

语种： 英文

作者： Liu, Huanyao;Meng, Cen;Wang, Yi;Liu, Xinliang;Li, Yong;...

期刊： Journal of Environmental Management,2022年321:115962 ISSN：0301-4797

通讯作者： Yi Wang

作者机构： [Liu, Huanyao] Hunan Agr Univ, Coll Resource & Environm, Changsha 410128, Peoples R China.;[Wang, Yi] Ludong Univ, Coll Resources & Environm Engn, Yantai 264025, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Meng, Cen; Liu, Xinliang] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Meng, Cen; Liu, Xinliang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Li, Yong] Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atmo, Beijing 100029, Peoples R China.

通讯机构： [Yi Wang] C;College of Resources and Environmental Engineering, Ludong University, Yantai, 264025, China

关键词： Agricultural pollution;Land use;River pollution;Rivers;Topography;Tropics;Watersheds;Buffer zones;Change-point analysis;Class level;Landscape metric;Landscape pattern;N pollutions;Riparian buffer zones;Soil property;Spatial scale;Stream water;Water quality;ammonia;nitrate;nitrogen;river water;nitrogen;water;agricultural development;soil property;subtropical region;topography;water quality;watershed;agricultural land;Article;China;controlled study;lake basin;land use;landscape;nitrogen concentration;soil property;stream (river);topography;water monitoring;water pollution;watershed;chemistry;environmental monitoring;procedures;river;soil;water pollutant;water pollution;China;Environmental Monitoring;Nitrogen;Rivers;Soil;Water;Water Pollutants, Chemical;Water Pollution

摘要： Multidimensional (coupled land use, soil properties, and topography) landscape effects on stream water nitrogen (N) are complex and scale-dependent. However, studies that identify critical buffer zones that explain large variations in riverine N, and estimate specific thresholds of multidimensional landscape patterns at the class level, result in a sudden changes in riverine N pollution, are still limited. Here, a new multidimensional landscape metric that combined land use, soil properties, and topography effects was applied to various riparian buffer zones and sub-watershed scales, and their relationships to riverine N levels were investigated. We used stream water ammonium−N, nitrate−N, and total−N concentrations datasets, from 2010 to 2017, in the nine subtropical sub-watersheds in China. The results of model selection and model averaging in ordinary least squares regressions, indicated that the riparian buffer zone with widths of 400 m, had more pronounced influence on water NH4–N and TN levels than at other scales. Within the 400 m buffer zone, the key landscape metrics for NH4–N, NO3–N and TN concentrations in stream water were different, and explained up to 43.35%–76.55% (adjusted R2) of the total variation in river N levels. When ENN_MNClass17 below 39–56 m, PDClass8 above 4.63–6.55 n/km2, PLANDClass27 above 23–29%, and CONTIG_MNClass42 below 0.35–0.37% within the 400 m buffer zone, riverine NH4–N and TN would be abruptly increased. This study provided practical ideas for regulation regarding landscape management linked to watershed structure, and identified reference thresholds for multidimensional landscape metrics, which should help reduce riverine N pollution in subtropical China. © 2022 Elsevier Ltd

语种： 英文

作者： Du, Huihui;Li, Yang;Wan, Dan;Sun, Chuanqiang;Sun, Jing

期刊： Journal of Hazardous Materials,2022年429:128292 ISSN：0304-3894

通讯作者： Sun, J

作者机构： [Du, Huihui; Li, Yang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410127, Peoples R China.;[Sun, Chuanqiang; Wan, Dan] Tianjin Univ, Sch Earth Syst Sci, Tianjin 300072, Peoples R China.;[Sun, J; Sun, Jing] Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang 550081, Peoples R China.

通讯机构： [Sun, J ] C;Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang 550081, Peoples R China.

关键词： Arsenic;Groundwater;Nuclear magnetic resonance spectroscopy;Secondary ion mass spectrometry;Water quality;X ray photoelectron spectroscopy;Abandoned smelter;Different soils;Emerging contaminant;Hunan province;Nano scale;Nano-scale secondary ion mass spectrometry;Secondary ion-mass spectrometry;Soil components;Soil profiles;Vertical migration;Soils;aluminum silicate;arsenic;ground water;iron oxide;soil organic matter;tungsten;arsenic;iron;tungsten;groundwater;kaolinite;sequential extraction;soil organic matter;tungsten;vertical migration;water quality;adsorption;Article;carbon nuclear magnetic resonance;chemical composition;China;concentration (parameter);elemental analysis;fractionation;geochemical analysis;secondary ion mass spectrometry;smelter;soil;soil analysis;soil pollution;water quality;X ray photoemission spectroscopy;chemistry;environmental monitoring;procedures;soil;soil pollutant;China;Hunan;Arsenic;Environmental Monitoring;Iron;Soil;Soil Pollutants;Tungsten

摘要： As an emerging contaminant, tungsten's distribution and speciation in soils are far from understood. In this study, two soil profiles near a typical abandoned tungsten smelter in Hunan Province, China were collected and investigated, to ascertain the binding and association of tungsten with different soil components and subsequently to understand its mobility. The data showed that past tungsten smelting activities resulted in elevated concentrations of both tungsten and arsenic in the soil profiles, both of which ranged from dozens of to a few hundred mg/kg. Nano-scale secondary ion mass spectrometry (NanoSIMS) was employed to quantify the distribution and association of tungsten with various other elements. Combined with sequential extraction and mineralogical analysis, the data from NanoSIMS showed that aluminosilicates including kaolinite and illite were the most important mineral hosts for tungsten, whereas arsenic was predominantly bound to iron (oxyhydr)oxides. Additional data from 13C nuclear magnetic resonance and X-ray photoelectron spectroscopy revealed that soil organic matter retained tungsten in deep soils (>70 cm) by binding tungsten through carboxyls on aromatic rings. Compared to arsenic, tungsten migrated deeper in the soil profiles, suggesting its higher mobility and potential risk to groundwater quality. © 2022 Elsevier B.V.

语种： 英文

作者： Peng, Zenghui;Du, Yuhang;Niu, Shiyu;Xi, Lianlian;Niu, Yandong;...

期刊： FRONTIERS IN PLANT SCIENCE,2022年13:989931 ISSN：1664-462X

通讯作者： Li, Y.

作者机构： [Xi, Lianlian; Li, Youzhi; Du, Yuhang; Niu, Shiyu; Peng, Zenghui] Hunan Agr Univ, Coll Resources & Environm, Changsha, Peoples R China.;[Xi, Lianlian; Li, Youzhi; Du, Yuhang; Niu, Shiyu; Peng, Zenghui] Hunan Agr Univ, Hunan Prov Key Lab Rural Ecosyst Hlth Dongting La, Changsha, Peoples R China.;[Niu, Yandong] Hunan Acad Forestry, Changsha, Peoples R China.;[Niu, Yandong] Hunan Dongting Lake Wetland Ecosyst Natl Position, Yueyang, Peoples R China.

通讯机构： [Li, Y.] C;College of Resources and Environment, China

关键词： harvest;litter decomposition;nitrogen sinks;non-harvest;phosphorus sinks;relative release indices

摘要： Plant non-harvest changes element circulation and has a marked effect on element sinks in the ecosystem. In this study, a field investigation was conducted on the fixation of nitrogen and phosphorus in Miscanthus lutarioriparius, the most dominant plant species in the Dongting Lake wetlands. Further, to quantitatively compare the difference in nitrogen and phosphorus sinks between harvest and non-harvest, an in situ experiment on the release of the two elements from two types of litters (leaves and stems) was studied. The nitrogen concentrations in the plant had no significant relationship with the environmental parameters. The phosphorus concentrations were positively related to the plot elevation, soil organic matter, and soil total potassium and were negatively related to the soil moisture. The leaves demonstrated a higher decomposition coefficient than that of the stems in the in situ experiment. The half decomposition time was 0.61 years for leaves and 1.12 years for stems, and the complete decomposition time was 2.83 years for leaves and 4.95 years for stems. Except for the nitrogen concentration in the leaves, all the concentrations increased during the flood period. All concentrations unsteadily changed in the backwater period. Similarly, except for the relative release index of nitrogen in the leaves, all the relative release indices decreased in the flood period. At the end of the in situ decomposition experiment, the relative release indices of both the nitrogen and phosphors were greater than zero, indicating that there was a net release of nitrogen and phosphorus. Under the harvest scenario, the aboveground parts of the plant were harvested and moved from the wetlands, thus increasing the nitrogen and phosphorus sinks linearly over time. The fixed nitrogen and phosphorus in the aboveground parts were released under the non-harvest scenario, gradually accumulating the nitrogen and phosphorus sinks from the first year to the fifth year after non-harvest, reaching a maximum value after the fifth year. This study showed that the nitrogen and phosphorus sinks greatly decreased after the non-harvest of M. lutarioriparius compared to that after harvest. It is recommended to continue harvesting the plant for enhancing the capacity of element sinks.

语种： 英文

作者： Meng, Cen;Liu, Huanyao;Li, Yuyuan;Shen, Jianlin;Li, Xi;...

期刊： Agricultural Water Management,2022年274:107953 ISSN：0378-3774

通讯作者： Li, Yuyuan(liyy@isa.ac.cn)

作者机构： [Li, Yuyuan; Wu, Jinshui; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Changsha Res Stn Agr & Environm Monitoring, Changsha 410125, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Li, Xi; Meng, Cen; Shen, Jianlin] Univ Chinese Acad Sci, Beijing 10049, Peoples R China.;[Liu, Huanyao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.

通讯机构： [Yuyuan Li] K;Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China<&wdkj&>Changsha Research Station for Agricultural and Environment Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China<&wdkj&>University of Chinese Academy of Sciences, Beijing 10049, China

关键词： Farm pond;Water quality;Structural equation modeling;Self-organizing map;Spatiotemporal variability

摘要： Water quality deterioration, such as eutrophication, can contribute to the degradation of farm pond ecosystems, threatening numerous ecological services and socioeconomic benefits. However, the variability of water quality and the complexity of influencing variables pose large uncertainties for pond management practices and watershed planning. This study integrated a self-organizing map (SOM) and partial least squares structural equation modeling (PLS-SEM) to evaluate the nitrogen (N) and phosphorus (P) variations in 39 typical farm ponds in the Dongting Lake basin, and related the variations to pond internal factors, external environment, and agronomic management. The results indicated that 39 monitored farm ponds faced a high risk of eutrophication owing to high N and P levels, and that total N (TN), total P (TP), and particulate P (PP) generally exceeded the threshold of level V surface water quality standards in China (2.0 mg N L−1 and 0.2 mg P L−1). Simultaneously, pond water quality showed high spatiotemporal variability, and pollution hotspots occurred mostly during the overlapping periods of fallow-dry-winter and planting-rainy-spring. Based on the constructed SEM model, external environmental factors (meteorology, catchment landscape composition, configuration, topography, and soil chemical properties), pond internal characteristics, and agronomic management combined explained 60.2 ± 2.9 % and 54.2 ± 3.1 % of the N and P variations, respectively. There were intricate interactions among the above latent variables, including such meteorology positively moderated the paths of soil chemical properties→pond P and landscape composition→pond N and P; landscape composition, soil, and pond internal characteristics mediated the effects of other variables on variations of N and P. The total effects (indirect effects + direct effects) of landscape composition on the variations of pond N and P were higher than those of other variables. Among all the indicators composing latent variables, agricultural and residential land area percentage, rainfall, water depth, and fish farming were relatively important in pond water quality variations. The constructed model and analytical results offer essential information for the accurate management and restoration of pond water quality. © 2022 Elsevier B.V.

语种： 英文

作者： Meng, Cen;Liu, Huanyao;Li, Yuyuan*;Shen, Jianlin;Li, Xi;...

期刊： Journal of Environmental Management,2022年315:115164 ISSN：0301-4797

通讯作者： Li, Yuyuan

作者机构： [Li, Yuyuan; Wu, Jinshui; Gong, Dianlin; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Gong, Dianlin; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Changsha Res Stn Agr & Environm Monitoring, Changsha 410125, Peoples R China.;[Li, Yuyuan; Wu, Jinshui; Li, Xi; Meng, Cen; Shen, Jianlin] Univ Chinese Acad Sci, Beijing 10049, Peoples R China.;[Liu, Huanyao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Deng, Yue] Cent South Univ Forestry & Technol, Coll Forestry, Changsha 410004, Peoples R China.

通讯机构： [Yuyuan Li] K;Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China<&wdkj&>Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China<&wdkj&>University of Chinese Academy of Sciences, Beijing, 10049, China

关键词： phosphorus;river water;phosphorus;agricultural production;agricultural soil;buffering;catchment;hydrology;identification method;landscape change;numerical model;phosphorus;topography;agricultural land;aquatic environment;Article;biogeochemical cycle;catchment area (hydrology);China;environmental management;environmental protection;human impact (environment);lake basin;land use;landscape;partial least squares regression;soil property;spatiotemporal analysis;structural equation modeling;surface soil;topography;water conservation;water sampling;chemistry;ecosystem;environmental monitoring;hydrology;river;soil;China;Dongting Basin;Hunan;China;Ecosystem;Environmental Monitoring;Hydrology;Phosphorus;Rivers;Soil

摘要： The catchment phosphorus buffering capacity (PBF) determines the pressure-state-response relationship between anthropogenic P inputs and aquatic ecosystems at a catchment scale, and is affected by biogeochemical, hydrological, and ecological catchment characteristics. However, the complex relationship between these catchment characteristic factors and their impact pathways on PBF remains ambiguous, leading to large uncertainty in balancing agricultural productivity and water conservation via improving BF through management practices. In this study, the short-term buffering index, calculated from net anthropogenic P input and riverine P exports, was used to quantify the spatiotemporal variations in PBF in source agricultural catchments in the Dongting Lake basin. Partial least squares structural equation modeling was used to investigate the relationship between the PBF and the catchment characteristics. The results indicate that catchment PBF was directly determined by soil properties and hydrological conditions, while landscape patterns significantly mediated the effects of topography on soil and hydrology. Considering the pathway preferences of the model, landscape patterns could be the priority for characterizing and regulating PBF. According to a change-point analysis, the probability of PBF weakening increases dramatically when the proportion of farmland (Farm%) > 24.6%, degree of patch interspersion (Contagion index) < 64.5%, and Perimeter-Area Ratio Distribution (PARA) > 348.7. These findings provide new insights into catchment buffering mechanisms and can be used to promote the simultaneous achievement of agricultural production and environmental conservation goals. © 2022 Elsevier Ltd

语种： 英文

作者： Zhu, Kunheng;Li, Zhenwei;Duan, Liangxia;Li, Yuanchen;Xu, Xianli

期刊： Journal of Hydrology,2022年607:127474 ISSN：0022-1694

通讯作者： Li, ZW

作者机构： [Zhu, Kunheng; Li, Yuanchen; Duan, Liangxia] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Li, Zhenwei; Xu, Xianli] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Huanjiang Observat & Res Stn Karst Ecosyst, Changsha 410125, Peoples R China.;[Li, Zhenwei; Xu, Xianli] Guangxi Ind Technol Res Inst Karst Rocky Desertif, Nanning 530201, Peoples R China.;[Li, Zhenwei; Xu, Xianli] Guangxi Key Lab Karst Ecol Proc & Serv, Huanjiang 547100, Peoples R China.

通讯机构： [Li, ZW ] C;Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Huanjiang Observat & Res Stn Karst Ecosyst, Changsha 410125, Peoples R China.

关键词： Evapotranspiration;Forecasting;Multivariant analysis;Runoff;Sediment transport;Signal processing;Watersheds;Different time scale;Eco-hydrology;Empirical Mode Decomposition;Empirical mode decomposition method;Karst landform;Multi scale analysis;Multivariate empirical mode decomposition;Prediction modelling;Sediment loads;Soil erosion;Landforms;evapotranspiration;karst hydrology;mountain stream;potential evapotranspiration;sediment analysis;watershed;China;Wujiang Basin

摘要： At different time scales, the potential factors influencing changes in sediment transport vary. Because the processes of each impact factor overlaps on different time scales, it is challenging to evaluate the complex multi-scale relationships between monthly sediment load and its potential impact factors. The objective of this study was to investigate the scale-specific main factors influencing monthly sediment loads using the multivariate empirical mode decomposition (MEMD) method. Monthly sediment loads and five potential influencing factors (runoff, precipitation, air temperature, potential evapotranspiration, and enhanced vegetation index) during 2003–2017 were collected in the Wujiang karst watershed of southwest China. The MEMD method was used to decompose the temporal series of monthly sediment load into seven intrinsic mode functions (IMF) and residuals using a Hilbert transform. The sum of variance contribution rates of IMF1 (3.2 months), IMF2 (5.5 months) and IMF3 (12.1 months) was more than 90%. Although temperature and potential evapotranspiration significantly affect monthly sediment loads at the observation scale, no significant relationships were observed between them at some specific scales after MEMD. The accuracy of the prediction model after MEMD was better than that of the prediction model using original data. Runoff and precipitation were important predictors in the prediction model. This study shows the advantages of the MEMD method for analyzing non-stationary and nonlinear hydrological processes, and this useful tool is recommended for application in other karst watersheds. © 2022 Elsevier B.V.

语种： 英文

作者： Meng, Cen;Liu, Huanyao;Li, Yuyuan*;Wang, Yi;Li, Xi;...

期刊： Biogeochemistry,2021年152(2-3):161-177 ISSN：0168-2563

通讯作者： Li, Yuyuan

作者机构： [Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Yong; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Changsha Res Stn Agr & Environm Monitoring, Inst Subtrop Agr, 644,Second Yuanda Rd, Changsha 410125, Peoples R China.;[Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Yong; Li, Xi; Meng, Cen; Shen, Jianlin] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.;[Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Yong; Li, Xi; Meng, Cen; Shen, Jianlin] Univ Chinese Acad Sci, Beijing 10049, Peoples R China.;[Liu, Huanyao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Fan, Xiang] Hunan Agr Univ, Coll Water Resources & Civil Engn, Changsha 410128, Peoples R China.

通讯机构： [Li, Yuyuan] C;Chinese Acad Sci, Changsha Res Stn Agr & Environm Monitoring, Inst Subtrop Agr, 644,Second Yuanda Rd, Changsha 410125, Peoples R China.

关键词： Riverine nitrogen exports;Legacy nitrogen;Net anthropogenic nitrogen inputs;Landscape pattern;Subtropics;Sources catchment

摘要： Changes in the landscape pattern can disturb legacy nitrogen (N) release by influencing hydrological and biogeochemical processes; thus, understanding the effects of landscape patterns on riverine N exports from legacy sources is critical for preparing water quality improvement strategies. In this study, an empirical statistical model that incorporates the net anthropogenic nitrogen input (NANI), runoff coefficient, and residential land area percentage was used to quantify the contribution of legacy sources to annual riverine ammonium nitrogen (NH4+–N), nitrate nitrogen (NO3−–N), and total nitrogen (TN) exports in eight adjacent agricultural catchments in subtropical southern China. The results indicated that annual riverine NH4+–N, NO3−–N, and TN exports from legacy sources ranged from 0.36–1.03, 3.09–4.89, and 3.94–6.79kgha−1 year−1, respectively, during the 2012–2017 period. Redundancy analysis (RDA) was used to analyze the interactions between legacy N release and landscape metrics at both the landscape and class levels. The RDA results suggested that higher dispersion, lower shape complexity, and greater heterogeneity in landscape patches can enhance the release of legacy N at the landscape level. In agricultural and residential areas, higher release of legacy N was associated with patches that are unfragmented and have a low shape complexity, whereas in woodland areas, the opposite was true. These analyses provide scientific support for preparing legacy N control strategies from the perspective of landscape ecology. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG part of Springer Nature.

语种： 英文

作者： Yao, Xin;Luo, Kun;Niu, Yandong;Li, Youzhi;Ren, Bo

期刊： Bulletin of Environmental Contamination and Toxicology,2021年107(1):140-146 ISSN：0007-4861

通讯作者： Youzhi Li

作者机构： [Li, Youzhi; Ren, Bo; Yao, Xin] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Luo, Kun] Environm Monitoring Ctr Chenzhou, Chenzhou 423000, Peoples R China.;[Niu, Yandong] Hunan Acad Forestry, Changsha 410128, Peoples R China.

通讯机构： [Li, Youzhi] C;College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China.

关键词： Toxic metal pollutants;River sediment;Ecological risk

摘要： In this study, the concentrations of six toxic metals (Cd, Cr, Cu, Ni, Pb, and Zn) in surface sediments within the Yangtze, Yellow, Pearl, and Liaohe rivers, China, were analyzed, and their associated pollution statuses and potential ecological risks were assessed using the geoaccumulation index (Igeo), sediment quality guidelines (SQGs), and the potential ecological risk index (RI). Relatively high toxic metal concentrations were observed in the Pearl and Yangtze rivers, whereas relatively low concentrations were observed in the Yellow and Liaohe rivers. In the Yangtze, Pearl, and Liaohe rivers, the concentrations of these six toxic metals were higher than their background values. Based on the SQGs, the concentrations of Cd, Cr, and Cu in the four rivers were found to be higher than the threshold effect levels (TELs) but lower than the probable effect levels (PELs); however, the concentration of Ni exceeded the PEL in the Pearl River sediments. The Igeo index indicated that all four rivers were heavily contaminated with Cd. The RI of the Pearl and Yellow rivers was classed as high and low, respectively, and that of the Yangtze and Liaohe rivers as moderate. The pollution status of the sediments in the four major rivers was explored in relation to the geochemical background, the ecological toxicity of metals, and the sensitivity of the local benthic communities. These results provide meaningful information for directing river management priorities. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

语种： 英文

作者： Liu, Huanyao;Meng, Cen;Wang, Yi;Li, Yong;Li, Yuyuan;...

期刊： Ecological Indicators,2021年127:107781 ISSN：1470-160X

通讯作者： Wang, Yi(wangyi@isa.ac.cn)

作者机构： [Liu, Huanyao] Hunan Agr Univ, Coll Resource & Environm, Changsha 410128, Peoples R China.;[Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Yong; Meng, Cen; Liu, Xinliang] Chinese Acad Sci, Inst Subtrop Agr, Changsha Res Stn Agr & Environm Monitoring, Changsha 410125, Peoples R China.;[Wang, Yi; Li, Yuyuan; Wu, Jinshui; Li, Yong; Meng, Cen; Liu, Xinliang] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Peoples R China.

通讯机构： [Yi Wang] C;Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China<&wdkj&>Key Laboratory for Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China

关键词： Catchment environment;Landscape;Water quality;Topography;Soil type;Land use

摘要： Although a landscape is a multidimensional integrated synthesis, the relationship between land use and water quality was merely studied in relation to protecting the aquatic ecological service function from the ‘landscape perspective’. This study analyzed the integrated landscape pattern by coupling land use, soil property, and topography and determined the stream water total nitrogen (TN) and total phosphorus (TP) in Chinese subtropical catchments from 2010 to 2017 to reveal and quantify the relationship between multidimensional landscape patterns and stream water N and P levels using the GIS and partial least squares regression (PLSR) techniques. The results suggested that the areal proportions of tea field and residential area in the Ultisols and on the first three slope categories (0–28.02°) and paddy field in the Ultisols and on slope category I (0–5.35°) were positively correlated with the TN and TP, while forest in the Ultisols and on slope category IV (28.02–80.30°) was negatively correlated with the TN (p ≤ 0.05). For the multidimensional landscape metrics, the Euclidean nearest-neighbor distance (ENN_MN) and interspersion and juxtaposition index (IJI) were positively correlated with the TN, while the ENN_MN was positively correlated with the TP (p ≤ 0.05). The PLSR analysis explained the variations of TN and TP levels well (R2 ≥ 0.66), in which the areal proportions of the tea field and residential area in the Ultisols and on the first three slope categories (0–28.02°) and the paddy field in the Ultisols and on slope category I (0–5.35°) were the important variables for both TN and TP; however, the areal proportions of forest in the Ultisols and on slope category IV (28.02–80.30°) and the IJL were only important to the TN. Therefore, the multidimensional landscape pattern providing specific land use, soil property, and topography can be more capable in restoring and protecting stream N and P pollution at an applicable level. © 2021 The Authors

语种： 英文

作者： Zhou, Qiaoqiao;Yang, Nan*;Li, Youzhi*;Ren, Bo;Ding, Xiaohui;...

期刊： Global Ecology and Conservation,2020年22:e00925 ISSN：2351-9894

通讯作者： Li, Youzhi;Yang, Nan

作者机构： [Li, Youzhi; Zhou, Qiaoqiao; Ren, Bo; Yao, Xin; Bian, Hualin; Ding, Xiaohui] Hunan Agr Univ, Coll Resources & Environm, Hunan Prov Key Lab Rural Ecosyst Hlth Dongting La, Changsha 410128, Peoples R China.;[Yang, Nan] Hunan City Univ, Coll Architecture & Urban Planning, Yiyang 413000, Peoples R China.;[Yang, Nan] Hunan Prov Urban & Rural Ecol Planning & Restorat, Yiyang 413000, Peoples R China.

通讯机构： [Li, Youzhi; Yang, Nan] H;Hunan Agr Univ, Coll Resources & Environm, Hunan Prov Key Lab Rural Ecosyst Hlth Dongting La, Changsha 410128, Peoples R China.;Hunan City Univ, Coll Architecture & Urban Planning, Yiyang 413000, Peoples R China.

关键词： Mining and manufacturing;Rock weathering;Fertilizer and pesticide use;Principal component analysis;Mixed metal pollution;Surface water pollution

摘要： This study collected past sampling data on total concentrations of 12 heavy metals (Cd, Pb, Cr, Hg, Zn, Cu, Ni, Al, Fe, Mn, As, and Co) in surface water bodies, i.e., 168 rivers and 71 lakes, from 1972 to 2017. The intent was to investigate the levels and sources of heavy metal pollution across five decades and five continents. Mean heavy metal concentrations in global river and lake water, and the number of heavy metals with concentrations greater than the published threshold limits as per the standards of both the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA) were generally lower in the 1970s and 1980s than in the 1990s, 2000s, and 2010s. Over time, heavy metal pollution in surface water has changed from single metal pollution to mixed metal pollution. Heavy metal concentrations in water, and the number of heavy metals with concentrations above the threshold limits for both WHO and USEPA standards were lower in the developed countries of Europe and North America, and higher in the developing countries of Africa, Asia, and South America. Over time, the main sources of metal pollution have changed from mining and manufacturing to rock weathering and waste discharge. The main metal sources differed across the five continents, with fertilizer and pesticide use, along with rock weathering, being dominant in Africa. Mining and manufacturing, along with rock weathering, were dominant in Asia and Europe. Mining and manufacturing, along with fertilizer and pesticide use, were dominant sources in North America, while four sources (mining and manufacturing, fertilizer and pesticide use, rock weathering, and waste discharge) were responsible for the majority of heavy metal pollution in the river and lake water bodies of South America. Additionally, implementing rigorous standards on metal emissions and recycling metals from wastewater are effective for controlling heavy metal source pollution. (C) 2020 The Authors. Published by Elsevier B.V.

语种： 英文

作者： Liu, Zhilou;Li, Ziliang;Xie, Xiaofeng;Yang, Shu;Fei, Jiangchi;...

期刊： Environmental Science & Technology,2020年54(1):604-612 ISSN：0013-936X

通讯作者： Xu, Zhifeng;Liu, Hui

作者机构： [Li, Ziliang; Li, Yuhu; Xu, Zhifeng; Liu, Zhilou] JiangXi Univ Sci & Technol, Sch Met Engn, 86 Hongqi Rd, Ganzhou 341000, Peoples R China.;[Yang, Shu; Xie, Xiaofeng; Liu, Hui] Cent S Univ, Sch Met & Environm, 93 Lushan Rd, Changsha 410083, Peoples R China.;[Fei, Jiangchi] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.

通讯机构： [Xu, Zhifeng] J;[Liu, Hui] C;JiangXi Univ Sci & Technol, Sch Met Engn, 86 Hongqi Rd, Ganzhou 341000, Peoples R China.;Cent S Univ, Sch Met & Environm, 93 Lushan Rd, Changsha 410083, Peoples R China.

摘要： Fast and effective removal of elemental mercury in a wide temperature range is critical for the smelting industry. In this work, a recyclable magnetic iron sulfide/selenide sorbent is developed to capture and recover Hg0 from smelting flue gas. Benefiting from Se doping, the Hg0 capture performance of prepared FeSxSey is significantly enhanced compared with traditional iron sulfide, especially at high temperatures. Considering the recyclability and working temperature, FeS1.32Se0.11 exhibits the best Hg0 capture performance. The average capture rate of FeS1.32Se0.11 is 3.661 μg/g/min at 80 °C and its saturation adsorption capacity is 20.216 mg/g. The flue gas compositions have almost no effect on Hg0 capture. X-ray photoelectron spectroscopy and mercury thermal programmed desorption suggest that the stable active Se-Sn 2- adsorption site can combine with Hg0 to form HgSe, consequently improving Hg0 capture performance at high temperatures. After Hg0 capture, the spent FeSxSey can be collected by magnetic separation and regenerated through selective extraction, which facilitates harmless treatment and resource reuse of mercury. With the advantages of excellent Hg0 capture performance, wide operating temperature range, and remarkable recycling property, FeSxSey microparticles may be a promising sorbent for Hg0 capture in industrial applications, while opening a new avenue to realize the resource utilization toward toxic elements. © 2019 American Chemical Society.

语种： 英文

作者： Bian, Hualin;Li, Wei;Li, Youzhi*;Ren, Bo;Niu, Yandong;...

期刊： Global Ecology and Conservation,2020年21:e00867 ISSN：2351-9894

通讯作者： Li, Youzhi

作者机构： [Li, Youzhi; Ren, Bo; Bian, Hualin] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Li, Wei] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China.;[Zeng, Zhangquan; Niu, Yandong] Hunan Acad Forestry, Changsha 410004, Peoples R China.

通讯机构： [Li, Youzhi] H;Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.

关键词： Marsh;River;Lake;Reservoir;Forest land;Regional temperature

摘要： Based on the wetland areas recorded in the First National Inventory of Wetland Resources (FNIWR; 1999-2001) and the Second National Inventory of Wetland Resources (SNIWR; 2009-2011), as well as regional environmental parameters including meteorological conditions and land-use structure, the driving forces of changes in China's wetland area from the FNIWR to the SNIWR were investigated. The total area of China's wetlands larger than 1 km(2) decreased from 384.8 x 10(3) km(2) in the FNIWR to 350.8 x 10(3) km(2) in the SNIWR. Natural wetland areas, including marshes, rivers, lakes, and coastal wetlands, decreased by 33.8 x 10(3) km(2) over the study period, accounting for 99.4% of the decrease in the wetland area. Regions with decreased marsh and reservoir wetland areas were located mainly in Central and Eastern China, and those with increased river and lake wetland areas were located in Western China. There were no significant regression coefficients between the percentages of change in marsh and lake wetland areas and environmental parameters. However, changes in river wetland areas were positively regressed with changes in forest areas, mean annual temperature, and extreme minimum temperature, and changes in reservoir wetland areas were positively regressed with changes in city construction areas and mean annual temperature. Therefore, it seems that increased forest area and regional temperature alleviated the degradation of river wetland areas, while increased city construction areas and regional temperature alleviated the degradation of reservoir areas. (C) 2019 The Authors. Published by Elsevier B.V.

语种： 英文

作者： Chen, Yaoning*;Liang, Weiyu;Li, Yuanping*;Wu, Yanxin;Chen, Yanrong;...

期刊： Chemical Engineering Journal,2019年362:144-159 ISSN：1385-8947

通讯作者： Chen, Yaoning;Li, Yuanping

作者机构： [Chen, YN; Li, Yuanping; Chen, Yaoning; Chen, Yanrong; Liang, Weiyu; Zhao, Li; Wu, Yanxin; Xiao, Wei] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Chen, Yaoning; Chen, Yanrong; Liang, Weiyu; Zhao, Li; Wu, Yanxin; Xiao, Wei] Hunan Univ, Minist Educ, Key Lab Environm Biol & Pollut Control, Changsha 410082, Hunan, Peoples R China.;[Li, Yuanping] Hunan City Univ, Coll Municipal & Mapping Engn, Yiyang 413000, Hunan, Peoples R China.;[Zhang, Jiachao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Li, Hui] Hunan Acad Forestry, Inst Biol & Environm Engn, Changsha 410004, Hunan, Peoples R China.

通讯机构： [Chen, YN; Li, YP] H;Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.

关键词： Iron sulfide;Nanoparticles;Soil remediation;Water contamination

摘要： The presence of excessive pollutants in soil and water caused by the fast development of industry has been a challenge for the innovation of environmental remediation technologies. Nano-sized iron sulfide (FeS) particles have aroused researchers’ attention for environmental remediation over the decade owing to their high reactivity and large specific surface area. The aim of this paper is to provide a comprehensive review on the evolution of FeS nanoparticles for environmental decontamination. The synthesis for bare nano-sized FeS particles via physicochemical and biological methods, the modification for nano-sized FeS particles by coating stabilizers and loading supporting materials are described in this review. What's more, the applications of nano-scale FeS in soil and water remediation are also discussed, including the removal of halogenated hydrocarbon, radionuclide, heavy metals, and metalloid. Meanwhile, the interaction mechanisms, namely adsorption and redox reaction between contaminants and nano-sized FeS and the effect of remediation conditions have been summarized in this review. Moreover, some future research needs are also stated such as researching the fate of FeS nanoparticle after injecting into soil and water, enhancing the mobility of nano-sized FeS in soil and water, and measuring the toxicity to the organisms. © 2019 Elsevier B.V.

语种： 英文

作者： Chen, Yanrong;Chen, Yaoning*;Li, Yuanping*;Wu, Yanxin;Zeng, Ziping;...

期刊： Journal of Hazardous Materials,2019年378:120757 ISSN：0304-3894

通讯作者： Chen, Yaoning;Li, Yuanping

作者机构： [Chen, Yanrong; Chen, Yaoning; Wang, Sha; Wu, Yanxin; Zeng, Ziping; Xu, Ran] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Chen, Yanrong; Chen, Yaoning; Wang, Sha; Wu, Yanxin; Zeng, Ziping; Xu, Ran] Hunan Univ, Minist Educ, Key Lab Environm Biol & Pollut Control, Changsha 410082, Hunan, Peoples R China.;[Li, Yuanping] Coll Municipal & Mapping Engn Hunan City Univ, Yiyang 413000, Hunan, Peoples R China.;[Zhang, Jiachao] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Li, Hui] Hunan Acad Forestry, Inst Biol & Environm Engn, Changsha 410004, Hunan, Peoples R China.

通讯机构： [Chen, Yaoning] H;[Li, Yuanping] C;Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.;Coll Municipal & Mapping Engn Hunan City Univ, Yiyang 413000, Hunan, Peoples R China.

关键词： Co-composting;Heavy metals;Phanerochaete chrysosporium;Redundancy analysis;Sediment

摘要： The effects of Phanerochaete chrysosporium on the bioavailability of multiple heavy metals (Pb, Cd, Cu, and Zn) in river sediments were investigated by co-composting with the agricultural waste. The results showed that the Phanerochaete chrysosporium inoculation can greatly enhance the passivation on Cu, Pb and Cd during 60 days co-composting. The effects in the three metals followed the order: Cu>Cd>Pb. There were no differences for Zn whether inoculation with P. chrysosporium or not. Redundancy analysis (RDA) implied that more than 4/5 of the variation of all fractions data for all heavy metals was explained by all significant canonical axes. P. chrysosporium can change the significant parameters for each metal and enhance the explanatory power of RDA model. The inoculation can strengthen the effect of OM (organic matter) on the bioavailability of heavy metals, but weaken the contribution of pH.

语种： 英文

作者： Liu, Zhilou;Yang, Shu;Li, Ziliang;Xie, Xiaofeng;Li, Yuhu;...

期刊： Chemical Engineering Journal,2019年378:122075 ISSN：1385-8947

通讯作者： Xu, Zhifeng

作者机构： [Li, Ziliang; Li, Yuhu; Xu, Zhifeng; Liu, Zhilou] JiangXi Univ Sci & Technol, Sch Met Engn, 86 Hongqi Rd, Ganzhou 341000, Peoples R China.;[Yang, Shu; Xie, Xiaofeng] Cent South Univ, Sch Met & Environm, 93 Lushan Rd, Changsha 410083, Hunan, Peoples R China.;[Sun, Zhumei] North Univ China, Sch Environm & Safety Engn, 3 Xueyuan Rd, Taiyuan 030051, Shanxi, Peoples R China.;[Luo, Shuang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.

通讯机构： [Xu, Zhifeng] J;JiangXi Univ Sci & Technol, Sch Met Engn, 86 Hongqi Rd, Ganzhou 341000, Peoples R China.

关键词： Capture;Core-shell structure;Gaseous As2O3;Iron oxide;Magnetic composites

摘要： Gaseous arsenic capture from flue gas is of great concern due to the high toxicity of arsenic. In this study, a new type of sorbent, magnetic Fe3O4@C@Fe2O3 microparticles with a core-shell structure, was designed by taking advantages of the easy separation property of magnetic sorbents and the excellent adsorption property of Fe2O3 for the capture of arsenic. The Fe3O4@C@Fe2O3 material exhibits a three-layer structure with high specific surface area (27.242 m2 g−1), large pore volume (0.181 cm3 g−1) and excellent magnetic properties (74.1 emu g−1). The synthesized Fe3O4@C@Fe2O3 sorbent demonstrates better arsenic capture performance than Fe3O4, Fe3O4@C or commercial Fe2O3 materials. The capture rate of Fe3O4@C@Fe2O3 for gaseous As2O3 could reach 1.94 mg g−1 min−1 in optimal conditions, and its capacity is 36.22 mg g−1 with a breakthrough threshold of 50%. The performance tests indicate that gaseous As2O3 could be efficiently captured from simulated flue gas and that the presence of SO2 and O2 plays a crucial role in As2O3 capture. The capture mechanism indicates that the conversion of Fe3+/Fe2+ during the oxidation of SO2 by O2 can accelerate the formation of highly active chemisorbed oxygen, and then the adsorbed As2O3 can bond with chemisorbed oxygen to from stable Fe(III)-As(V) compound. After magnetic separation, the spent sorbent can be regenerated through alkali desorption, which facilitates the centralized control of arsenic and the recycling of sorbent. Therefore, the Fe3O4@C@Fe2O3 composite is a promising sorbent for gaseous As2O3 capture from SO2-containing flue gas due to its excellent separation and regeneration properties. © 2019

语种： 英文

作者： Yin, Xiang;Liu, Qiong;Yang, Yahui;Liu, Yang;Wang, Keke;...

期刊： International Journal of Hydrogen Energy,2019年44(2):594-604 ISSN：0360-3199

通讯作者： Li, Jie;Li, Wenzhang

作者机构： [Qiu, Xiaoqing; Yin, Xiang; Li, Jie; Liu, Qiong; Wang, Keke; Liu, Yang; Li, Wenzhang] Cent South Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Li, Wenzhang] Cent South Univ, Hunan Prov Key Lab Efficient & Clean Utilizat Man, Changsha 410083, Hunan, Peoples R China.;[Li, Yaomin] UCL, Dept Chem, 20 Gordon St, London WC1H 0AJ, England.;[Liu, Yang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Li, Dongwei] Chongqing Univ Educ, Div Sci Res Management, Chongqing 400065, Peoples R China.

通讯机构： [Li, Jie; Li, Wenzhang] C;Cent South Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;Cent South Univ, Hunan Prov Key Lab Efficient & Clean Utilizat Man, Changsha 410083, Hunan, Peoples R China.

关键词： Bias voltage;Copper oxides;Efficiency;Electrochemistry;Hydrogen;Iron compounds;Photocathodes;Photocurrents;Photoelectrochemical cells;Solar power generation;Titanium dioxide;Current density-voltage curves;Photoconversion efficiency;Photoelectrochemicals;Solar hydrogen;Solar water splitting;Tandem cells;Two-electrode systems;Water splitting;Bismuth compounds

摘要： An integrated solar water splitting tandem cell without external bias was designed using a FeOOH modified TiO 2 /BiVO 4 photoanode as a photoanode and p-Cu 2 O as a photocathode in this study. An apparent photocurrent (0.37 mA/cm 2 at operating voltage of +0.36 V RHE ) for the tandem cell without applied bias was measured, which is corresponding to a photoconversion efficiency of 0.46%. Besides, the photocurrent of FeOOH modified TiO 2 /BiVO 4 –Cu 2 O is much higher than the operating point given by pure BiVO 4 and Cu 2 O photocathode (∼0.07 mA/cm 2 at +0.42 V RHE ). Then we established a FeOOH modified TiO 2 /BiVO 4 –Cu 2 O two-electrode system and measured the current density-voltage curves under AM 1.5G illumination. The unassisted photocurrent density is 0.12 mA/cm −2 and the corresponding amounts of hydrogen and oxygen evolved by the tandem PEC cell without bias are 2.36 μmol/cm 2 and 1.09 μmol/cm 2 after testing for 2.5 h. The photoelectrochemical (PEC) properties of the FeOOH modified TiO 2 /BiVO 4 photoanode were further studied to demonstrate the electrons transport process of solar water splitting. This aspect provides a fundamental challenge to establish an unbiased and stabilized photoelectrochemical (PEC) solar water splitting tandem cell with higher solar-to-hydrogen efficiency. © 2018 Hydrogen Energy Publications LLC

语种： 英文

作者： Liu, Wenhua;Yang, Yahui;Zhan, Faqi;Li, Dongwei;Li, Yaomin;...

期刊： International Journal of Hydrogen Energy,2018年43(18):8770-8778 ISSN：0360-3199

通讯作者： Li, Wenzhang;Li, Jie

作者机构： [Zhan, Faqi; Li, Jie; Li, Wenzhang; Liu, Wenhua] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Li, Dongwei; Li, Wenzhang] Chongqing Univ Educ, Div Sci Res Management, Chongqing 400065, Peoples R China.;[Yang, Yahui] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Li, Yaomin] UCL, Dept Chem, 20 Gordon St, London WC1H 0AJ, England.;[Tang, Xinde] Hunan Inst Technol, Dept Mat & Chem Engn, Hengyang 421002, Peoples R China.

通讯机构： [Li, WZ; Li, J] C;Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.

关键词： Annealing;Carbon dioxide;Electrochemistry;Fabrication;Formic acid;High resolution transmission electron microscopy;Microwave heating;Microwaves;Nanostructures;Oxide films;Scanning electron microscopy;X ray diffraction;CO2 reduction;Microscopic morphology;Microwave annealing;Photo-anodes;Photoelectrocatalytic activities;Photoelectrochemical measurements;Photoelectrochemical system;Ultra-fast;Tungsten compounds

摘要： Tungsten oxide (WO3) nanoplate films with a relatively rough surface were successfully fabricated via a simple hydrothermal method, followed by the hybrid microwave annealing (HMA) treatment only a few minutes for the first time. The microscopic morphology and phase were characterized by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), Raman spectrum and X-ray diffraction (XRD). Photoelectrochemical measurements demonstrated that the obtained WO3 film of microwave processing for 11 min exhibited the photocurrent density of 1.60 mA/cm2 at 1.2 V (vs. Ag/AgCl) and the IPCE value of 55% at 355 nm under an applied voltage of 1.0 V (vs. Ag/AgCl), which were about 3 and 2.5 times compared with the WO3 film prepared by the conventional annealing method, respectively. Moreover, the WO3-HMA films were applied to the versatile photoanode-driven photoelectrochemical system for CO2 reduction into formic acid. The maximum formic acid generation rate and faradaic efficiency of the WO3-HMA films were 9.21 μmol h−1 cm−2 and 45.45%, respectively. This study provided a facial and rapid method to synthesize the high-performance WO3 photoanodes with better photoelectrochemical and photoelectrocatalytic activities. © 2018 Hydrogen Energy Publications LLC

语种： 英文