摘要：
<jats:p>In the current work, the effects of biochar, vermicompost, as well as their combined application on ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in soils contaminated with potentially toxic elements (PTEs) were investigated. In this regard, four treatments were performed; among them, treatment A served as a control without additive, treatment B with vermicompost (2%), treatment C with biochar (2%), and treatment D with biochar (2%) plus vermicompost (2%). In addition, the abundance and structure of the AOA and AOB amoA gene were measured using quantitative PCR and high-throughput sequencing. The relationships between the microbial community, physicochemical parameters, and CaCl2-extractable PTEs were analyzed using the Pearson correlation method. We found that adding biochar and vermicompost promoted the immobilization of PTEs and nitrogen biotransformation. The rational use of biochar and vermicompost is beneficial for the growth of bacterial and fungal communities in soils polluted by PTEs. AOA and AOB amoA genes were stimulated by biochar, vermicompost, and their combination, but their structure was hardly affected.</jats:p>
摘要：
Although increasing attention has been paid to agronomic measures for reducing the heavy metal load in rice grain, the effects of duckweed-paddy co-cropping technology on the accumulation of cadmium (Cd) in rice grains remain unclear. To investigate its specific effects on Cd accumulation in paddy fields, three types of duckweed-like hydrophyte (DH), Azolla imbricata, Spirodela polyrrhiza, and Lemna minor were chosen for study. Their use resulted in a reduction of Cd content in rice grains from 0.40mg/kg to <0.20mg/kg, with A. imbricata yielding the best results (0.15mg/kg). The three types of DH reduced the available Cd content in the soil by 10% to 35% after the paddy tillering stage. The reduction of available Cd content was attributed to the absorption, high pH, and increase of relative abundance of special bacteria of immobilizing Cd. In addition, DH could regulate soil nitrogen leading to ammonium nitrogen increased from 75mg/kg to 100mg/kg, while nitrate nitrogen decreased from 0.55 to 0.1-0.3mg/kg. The increase of ammonium nitrogen content might induce the low Cd transfer ability in rice plant and then low Cd content in rice grain. This study demonstrated that DH has a good effect on the reduction of the Cd concentration in rice grains. Consequently, duckweed-paddy co-cropping technology offers a potential solution to heavy metal pollution and agricultural non-point source pollution, as it not only reduces Cd levels in rice plants, but also fixes nitrogen, reducing the need for nitrogen application.
作者机构：
[Junchun Li] Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China;[Junchun Li] Guangdong Key Laboratory of Contaminated Environmental Management and Remediation, Guangdong Provincial Academy of Environmental Science, Guangdong, 510045, China;[Xiao Yang] Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China. Electronic address: yanxl@igsnrr.ac.cn;[Xuejiao Tong] Yuhuan Enviromental Technology Co.Ltd, Shijiazhuang, Hebei, 050000, China;[Yutao Peng] School of Agriculture, Sun Yat-sen University, Shenzhen, Guangdong, 518107, China
通讯机构：
[Xiao Yang; Xiulan Yan] K;Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
关键词：
Cd accumulation;Intercropping;Potentially toxic elements;Safe production;Sustainable agriculture
摘要：
The utilization of Cd-contaminated soil in vegetable crop production can lighten the food crisis and improve the soil environmental resilience. Intercropping is a reliable technology in safety production from contaminated soil. A field-scale experiment was carried out to unravel how plant species and pattern affect the growth and Cd uptake of Chinese cabbage from Cd contaminated land. Among all the intercropping systems designed in this study, one row of Chinese cabbage intercropping with one row of Solanum nigrum L. is the best planting mode (high yields (2.78kg/m(2)) and low Cd accumulation (0.02mg/kg) of Chinese cabbage). Combined with the in-depth joint analysis of diverse soil physicochemical features (soil nutrient characteristics and microbial community structure), biomass yield and quality, and soil microbiological properties, we elaborated that two measures (screening hyperaccumulation types and controlling planting strip width) were the major factors in determining the growth of the aboveground and underground parts of Chinese cabbage respectively, thus directly regulating the application effectiveness of intercropping technology. The intertwined mechanisms (interspecific and intraspecific relationship) of different intercropping systems are summarized, which include better utilization of space, light and other resources in the aboveground part, bioavailability of nutrient, drive of soil bacteria and alleviated soil Cd stress in the underground part, etc. Our research outputs indicate the effectiveness and feasibility of intercropping can be improved by optimizing the streamline configuration and plant mode, which provide theory of reference and practical evidence for warranting the food safety and agricultural soil remediation simultaneously.
通讯机构：
[Yan-Hong Wang; Ji-Hui Wen] E;Ecology Department, College of Resources and Environment, Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>School of Forestry and Bio-technology, Zhejiang Agriculture & Forestry University, Hangzhou, 311300, China<&wdkj&>Ecology Department, College of Resources and Environment, Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Institute of Plant Protection, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
关键词：
Autotoxicity;Bacterium;Detoxification;Invasion;Advantage;Release;Decline;Over time
摘要：
Plant invasive success is attributed to invaders’ ecological advantages over their native neighbors. However, increasing evidence suggests that these advantages are expected to attenuate over time because of natural enemy accumulation, ecological evolution of native species and autotoxicity. We determined how an invasive Ageratina adenophora could remain its competitive advantages over time by avoiding its autotoxicity. Our results highlighted that the autotoxicity of A. adenophora in its invaded soil was reduced by some microbes. Moreover, an autotoxic allelochemical, 2-coumaric acid glucoside, detected in the invaded soil, demonstrated distinctly autotoxic effects on its seed germination and seedling growth . However, the autotoxic effects were greatly alleviated by a bacterium Bacillus cereus , accumulated by A. adenophora. Furthermore, the allelochemical could be almost completely degraded by B. cereus within 96 h. Accordingly, we speculate that A. adenophora could aggregate B. cereus to release its autotoxicity maintaining its competitive advantages over time.
Plant invasive success is attributed to invaders’ ecological advantages over their native neighbors. However, increasing evidence suggests that these advantages are expected to attenuate over time because of natural enemy accumulation, ecological evolution of native species and autotoxicity. We determined how an invasive Ageratina adenophora could remain its competitive advantages over time by avoiding its autotoxicity. Our results highlighted that the autotoxicity of A. adenophora in its invaded soil was reduced by some microbes. Moreover, an autotoxic allelochemical, 2-coumaric acid glucoside, detected in the invaded soil, demonstrated distinctly autotoxic effects on its seed germination and seedling growth . However, the autotoxic effects were greatly alleviated by a bacterium Bacillus cereus , accumulated by A. adenophora. Furthermore, the allelochemical could be almost completely degraded by B. cereus within 96 h. Accordingly, we speculate that A. adenophora could aggregate B. cereus to release its autotoxicity maintaining its competitive advantages over time.
期刊：
Science of The Total Environment,2023年905:167289 ISSN：0048-9697
通讯作者：
Zhang, X
作者机构：
[Zhang, Xin; Yang, Guang; Li, Jinglong; Chen, Baodong; Xing, Shuping; Fu, Gengxue] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.;[Zhang, Xin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Wu, Songlin] Univ Queensland, Sustainable Minerals Inst, Ctr Mined Land Rehabil, Brisbane, Qld 4072, Australia.;[Feng, Haiyan] China Univ Geosci Beijing, Sch Earth Sci & Resources, Beijing 100083, Peoples R China.;[Zhou, Yaoyu] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.
通讯机构：
[Zhang, X ] C;Chinese Acad Sci, Res Ctr Ecoenvironm Sci, 18 Shuangqing Rd, Beijing 100085, Peoples R China.
关键词：
AM fungi;Biochar;Cr tolerance;Plant metabolism;Soil properties
摘要：
Soil chromium (Cr) contamination has become an environmental problem of global concern. However, the joint effects of combined utilization of biochar and arbuscular mycorrhizal (AM) fungal inoculum, which are considered as two promising remediation strategies of soil heavy metal pollutions, on plant Cr resistance are still poorly understood. In this study, a two-factor pot experiment was conducted to investigate how biochar and AM fungus Rhizophagus irregularis regulate Medicago sativa growth, physiological trait, nutrient and Cr uptake, relevant gene expressions, soil properties, and Cr speciation, independently or synergistically. The results showed that biochar notably decreased AM colonization, while biochar and AM fungus could simultaneously increase plant dry biomass. The greatest growth promotion was observed in mycorrhizal shoots at the highest biochar level (50gkg(-1) soil) by 91 times. Both biochar application and AM fungal inoculation enhanced plant photosynthesis and P nutrition, but the promoting effects of AM fungus on them were significantly greater than that of biochar. In addition, the combined application of biochar and AM fungus dramatically reduced shoot and root Cr concentrations by up to 92% and 78%, respectively, compared to the non-amended treatment. Meanwhile, down-regulated expressions were observed for metal chelating-related genes. Furthermore, Cr translocation from roots to shoots was reduced by both two soil amendments. Transcriptional levels of genes involved in reactive oxygen species and proline metabolisms were also regulated by biochar application and AM fungal colonization, leading to alleviation of Cr phytotoxicity. Furthermore, AM fungal inoculation slightly elevated soil pH but decreased plant-available soil P, which was, by contrast, lifted by biochar addition. The combined application reduced soil acid-extractable Cr concentration by 40%. This study provides new insights into comprehensively understanding of the mechanisms of biochar and AM fungi combination on improving plant Cr tolerance.
通讯机构：
[Jiachao Zhang; Zhiyong Yan] H;Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, Hunan Agricultural University, Changsha 410028, China
作者机构：
[尹雪斐; 刘玉玲; 伍德; 黄薪铭; 张朴心; 铁柏清] College of Resources and Environment, Hunan Agricultural University, Changsha;410128, China;Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha;Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs, Changsha;[尹雪斐; 刘玉玲; 伍德; 黄薪铭; 张朴心; 铁柏清] 410128, China<&wdkj&>Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha
通讯机构：
[Li, F ] C;[Li, YZ ] H;Hunan Agr Univ, Coll Resources & Environm, Hunan Prov Key Lab Rural Ecosyst Hlth Dongting Lak, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, Inst Subtrop Agr, 644 Second St Yuanda Rd, Changsha 410125, Peoples R China.
关键词：
Hydrodynamic -water quality model;Water level;Water quality;Lake sluice;Dongting Lake
摘要：
River-connected lakes with floodplain characteristics have substantial effects on terrestrial hydrologic cycles and are highly sensitive to external disturbances; thus, large-scale hydraulic projects are often constructed in such lakes to mitigate problems in the water environment. However, the spatiotemporal dynamics of the water environment in river-connected lakes and the differences in the water environment before and after the hydraulic project operation have received little attention. Here, a well-established coupled hydrodynamic-water quality model was applied to estimate the effects of the Chenglingji Sluice (CS) operation on the hydrodynamic features and water quality of Dongting Lake, a typical river-connected lake in China. The model successfully reproduced the water level and water quality dynamics of Dongting Lake, with a Root Mean Square Error (RMSE) of 0.29-1.24 m for water level and a Mean Relative Error (MRE) of 5.76-10.28% and 6.25-8.14% for total nitrogen (TN) and permanganate index (CODMn), respectively. The spatiotemporal fluctuation of lake water levels was observed over different hydrological periods. Water quality varied considerably spatially, with considerable pollution in East Dongting Lake and the Xiang River inlet. Concentrations of NH3-N (ammonia nitrogen), TN, and total phosphorus (TP) first decreased and then increased during the study period, whereas CODMn concentrations displayed the opposite trend. After the CS operation, the water level increased to 27.11 m and the water surface area increased by 19.29% in the dry period; furthermore, the water quality in the CS operation scenario had low concentrations compared to that of the baseline scenario in the dry period, with concentrations ranging from 0.03 to 0.24 mg/L for TN, 0.001 to 0.015 mg/L for TP, 0.006 to 0.09 mg/L for NH3-N, and 0.02 to 0.22 mg/L for CODM, effectively improving the water environment of Dongting Lake. However, the subsequent reaction of the lake environment to changes in hydrological conditions after the CS operation requires further attention.
作者机构：
[杨宇; 郭婷婷; 刘孝利; 铁柏清] College of Resources and Environment, Hunan Agricultural University, Changsha;410128, China;Technology and Research Center for Irrigation Water Resource and uality Purification, Hunan Province, Changsha;[杨宇; 刘孝利; 铁柏清] 410128, China<&wdkj&>Technology and Research Center for Irrigation Water Resource and uality Purification, Hunan Province, Changsha;[杨宇; 郭婷婷; 刘孝利; 铁柏清] 410128, China
作者机构：
[铁柏清; 张威宇; 尹雪斐; 刘玉玲; 张朴心; 姚俊帆] College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China;[铁柏清; 张威宇; 尹雪斐; 刘玉玲; 张朴心; 姚俊帆] Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China;[铁柏清; 张威宇; 尹雪斐; 刘玉玲; 张朴心; 姚俊帆] Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs, Changsha 410128, China
通讯机构：
[Pufeng Qin; Zhibin Wu] C;[Hui Wang] D;Department of Chemical Engineering, University College London, London WC1E 7JE, UK<&wdkj&>College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, PR China<&wdkj&>Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha 410128, PR China
摘要：
As a metal-free polymer, graphitic carbon nitride (g-C3N4) has spurred extensive consideration over their inor-ganic counterparts due to the unique physical and chemical properties. However, the low specific surface area, high charge recombination rate and insufficient light absorption limit its application in the field of photo -catalysis. Sulfur doping has been demonstrated as an efficient strategy for to promote light absorption and radiative carrier separation. On the basis of sulfur-doped carbon nitride, many of its modified composites have been synthesized and applied in photocatalysis, and have achieved dazzling results. Here, we introduce the basic properties of sulfur doped carbon nitride and its preparation method, and then discuss the effective method of controlling the introduction of sulfur doped g-C3N4. In addition, the achievement of sulfur doped g-C3N4 for several applications, including water splitting, carbon dioxide reduction, organic compounds degradation, inorganic matter transformation, nitrogen fixation and bacteria disinfection, were comprehensively reviewed. Finally, outstanding challenges and prospective perspectives are discussed, which might provide a new idea for the photocatalysts design for photocatalytic activity improvement.
作者机构：
[Yang, Guang; Duan, Guilan; Cao, Jinman] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.;[Lin, Aijun; Cao, Jinman] Beijing Univ Chem Technol, Coll Chem Engn, Beijing 100029, Peoples R China.;[Duan, Guilan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Zhou, Yaoyu] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[You, Siming] Univ Glasgow, James Watt Sch Engn, Glasgow G128QQ, Scotland.
通讯机构：
[Guang Yang] S;State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
关键词：
Cu;Fermentative hydrogen production;Inhibition;Metagenomic analysis;Microbial community structure
摘要：
Cu is widely present in the feedstocks of dark fermentation, which can inhibit H2 production efficiency of the process. However, current understanding on the inhibitory mechanisms of Cu, especially the microbiological mechanism, is still lacking. This study investigated the inhibitory mechanisms of Cu2+ on fermentative hydrogen production by metagenomics sequencing. Results showed that the exposure to Cu2+ reduced the abundances of high-yielding hydrogen-producing genera (e.g. Clostridium sensu stricto), and remarkably down-regulated the genes involved in substrate membrane transport (e.g., gtsA, gtsB and gtsC), glycolysis (e.g. PK, ppgK and pgi-pmi), and hydrogen formation (e.g. pflA, fdoG, por and E1.12.7.2), leading to significant inhibition on the process performances. The H2 yield was reduced from 1.49 mol H2/mol-glucose to 0.59 and 0.05 mol H2/mol-glucose upon exposure to 500 and 1000 mg/L of Cu2+, respectively. High concentrations of Cu2+ also reduced the rate of H2 production and prolonged the H2-producing lag phase.
