作者机构：
[Zhang, Weiluo; Hsieh, Shihhuan; Li, Yuanhua; Yang, Xiaofang; Chen, Yuan; Feng, Kejun; Zheng, Lei] Huizhou Univ, Sch Chem & Mat Engn, Huizhou, Peoples R China.;[Li, Yuanhua] Huizhou Univ, Guangdong Prov Key Lab Elect Funct Mat & Devices, Huizhou, Peoples R China.;[Li, Mingzhu] Shantou Univ, Dept Chem, Shantou, Guangdong, Peoples R China.;[Li, Mingzhu] Shantou Univ, Key Lab Preparat & Applicat Ordered Struct Mat Gua, Shantou, Guangdong, Peoples R China.;[Li, Huiling] South China Agr Univ, Coll Mat & Energy, Key Lab Biobased Mat & Energy, Minist Educ, Guangzhou, Peoples R China.
通讯机构：
[Feng, KJ; Zheng, L ] H;Huizhou Univ, Sch Chem & Mat Engn, Huizhou 516007, Peoples R China.
关键词：
Fluorescent probe;carbon dots;point-of-care test strips;tetracycline
摘要：
The overuse of tetracycline (TC) has led to the accumulation of antibiotic residues in drinking water and animal products, which can consequently lead to bacteria resistance and chronic disease in humans. Urgently addressing the need for a rapid, user-friendly, and point-of-care test for TC detection. In this work, we use cyclen and citric acid to synthesise carbon dots (CDs) with a unique ring-shaped structure on their surface and combine them with europium (Eu(3+)) to form an Eu-CDs fluorescent probe. In the presence of TC in aqueous systems, the Eu-CDs probe emits two distinctive fluorescent signals: the stable blue emission from cyclen-modified CDs and the red emission from Eu(3+),showing a proportional increase with TC concentration. The developed Eu-CDs probe demonstrates accurate and selective detection capabilities for TC class antibiotics among various interfering factors. The Eu-CDs probe exhibits excellent linearity within the concentration range of 0.04-2.4 µM and achieves an impressive detection limit of 2.7 nM. Moreover, point-of-care Eu-CDs test strips are designed, allowing convenient on-site TC analysis through the detection of a colour change from blue to red under a portable UV light. The results highlight the effectiveness of the proposed dual-mode ratiometric fluorescent Eu-CDs probe and test strips, offering a practical point-of-care testing strategy for real-world TC detection applications.
期刊：
International Journal of Biological Macromolecules,2024年259(Pt 2):129229 ISSN：0141-8130
通讯作者：
Chen, Bingjie;Xu, Q
作者机构：
[Liang, Yu-Min; Chen, Zhi; Zheng, Pei-Ji; Chen, Bingjie; Xu, Qing; Li, Kang-Li; Xu, Q] Guangzhou Med Univ, GMU GIBH Joint Sch Life Sci, Guangdong Hong Kong Macau Joint Lab Cell Fate Regu, Hong Kong 511436, Peoples R China.;[Zhang, Guo-Qiang] Fujian Agr & Forestry Univ, Key Lab Natl Forestry & Grassland Adm Orchid Conse, Fuzhou 350002, Peoples R China.;[Yan, Binghua] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Rizwana, Humaira; Elshikh, Mohamed Soliman] King Saud Univ, Coll Sci, Dept Bot & Microbiol, PO 2455, Riyadh 11451, Saudi Arabia.
通讯机构：
[Chen, BJ; Xu, Q ] G;Guangzhou Med Univ, GMU GIBH Joint Sch Life Sci, Guangdong Hong Kong Macau Joint Lab Cell Fate Regu, Hong Kong 511436, Peoples R China.
摘要：
The medicinal Dendrobium species of Orchidaceae possess significant pharmaceutical value, and modern pharmacological research has shown that Dendrobium contains many important active ingredients. Alkaloids, the crucial components of medicinal Dendrobium, demonstrate beneficial healing properties in cardiovascular, cataract, gastrointestinal, and respiratory diseases. Members of the cytochrome P450 monooxygenase (CYP) gene family play essential roles in alkaloid synthesis, participating in alkaloid terpene skeleton construction and subsequent modifications. Although studies of the CYP family have been conducted in some species, genome-wide characterization and systematic analysis of the CYP family in medicinal Dendrobium remain underexplored. In this study, we identified CYP gene family members in the genomes of four medicinal Dendrobium species recorded in the Pharmacopoeia: D. nobile, D. chrysotoxum, D. catenatum, and D. huoshanense. Further, we analyzed the motif composition, gene replication events, and selection pressure of this family. Syntenic analysis revealed that members of the clan 710 were present on chromosome 18 in three medicinal Dendrobium species, except for D. nobile, indicating a loss of clan 710 occurring in D. nobile. We also conducted an initial screening of the CYP genes involved in alkaloid synthesis through transcriptome sequencing. Quantitative real-time reverse transcription PCR showed that the expression of DnoNew43 and DnoNew50, homologs of secologanin synthase involved in the alkaloid synthesis pathway, was significantly higher in the stems than in the leaves. This result coincided with the distribution of dendrobine content in Dendrobium stems and leaves, indicating that these two genes might be involved in the dendrobine synthesis pathway. Our results give insights into the CYP gene family evolution analysis in four medicinal Dendrobium species for the first time and identify two related genes that may be involved in alkaloid synthesis, providing a valuable resource for further investigations into alkaloid synthesis pathway in Dendrobium and other medicinal plants.
摘要：
Utilizing an acid-resistant biological soil crust (BSC) species that we discovered, we developed a device capable of efficiently removing cadmium (Cd) from mine wastewater with varying levels of acidity. Our research has demonstrated that this particular BSC species adapts to acidic environments by regulating the balance of fatty acids and acid-resistant enzymes. At a Cd concentration of 5 mg/L, the BSC grew well. When the initial Cd concentration was 2 mg/L, and the flow rate was set at 1 mL/min (at pH levels of 3, 4, and 5), BSC had a high removal rate of Cd, and the removal rate increased with the increase of pH (from 90% to 97%). Chemisorption is the primary removal mechanism in the initial stage, where the functional groups and minerals on the surface of the BSC play a significant role. In addition, BSC also adapts to Cd stress by changing bacterial community structure. It was discovered through infrared spectroscopy and two-dimensional correlation analysis that hydrophilic groups, specifically phosphate and carboxyl groups, exhibited the highest reactivity during the Cd binding process. Protein secondary structure analysis confirmed that as the pH increased, the adsorption capacity of the BSC increased; making biofilm formation easier. This study presents a novel approach for the treatment of acidic wastewater.
期刊：
Soil Biology and Biochemistry,2023年178:108953 ISSN：0038-0717
通讯作者：
Jie Zhao
作者机构：
[Zhao, Jie; Liao, Xionghui] Chinese Acad Sci, Inst Subtrop Agr, Key Lab Agroecol Proc Subtrop Reg, Changsha 410125, Hunan, Peoples R China.;[Fu, Shenglei] Henan Univ, Coll Environm & Planning, Kaifeng 475004, Peoples R China.;[Zhao, Jie] Guangxi Ind Technol Res Inst Karst Rocky Desertifi, Nanning 530012, Guangxi, Peoples R China.;[Zhao, Jie; Liao, Xionghui] Chinese Acad Sci, Huanjiang Observat & Res Stn Karst Ecosyst, Huanjiang 547100, Guangxi, Peoples R China.;[Liao, Xionghui] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Jie Zhao] K;Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China<&wdkj&>Guangxi Industrial Technology Research Institute for Karst Rocky Desertification Control, Nanning, Guangxi, 530012, China<&wdkj&>Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang, Guangxi, 547100, China<&wdkj&>Guangxi Key Laboratory of Karst Ecological Processes and Services, Huanjiang, Guangxi, 547100, China
摘要：
Soil microbes and fauna as key components of belowground food webs play important roles in energy flux and carbon cycling in terrestrial ecosystems. However, it remains unclear whether forestry management regimes alter the energetic structure of soil food webs and thereby reshape the patterns of soil CO2 emissions in planted forest. Here, we tested the effects of legume (Cassia alata) addition, understory removal, understory removal with legume addition and all plants removal on energy fluxes through soil food webs and soil CO2 flux in the wet and dry seasons. We show that soil heterotrophic respiration contributed 36.9-57.8% of total CO2 flux in the soil. In the dry season, C. alata addition increased soil heterotrophic respiration by 24.6% and 57.3%, respectively, when compared with the control and understory removal treatment. Compared with the understory removal treatment, the total energy flux across the whole food web increased with legume addition (i.e., C. alata addition and understory removal with C. alata addition). Legume addition supported a high proportion of energy flux through herbivorous nematodes, whereas understory vegetation removal supported a high proportion of energy flux through microbivorous nematodes. Less energy fluxes were transferred from basal resources to fungivorous mites and collembolans compared with microbivorous and herbivorous nematodes. The total soil CO2 flux was posi-tively correlated with metabolic rates of herbivorous and omnivorous-predatory nematodes, and energy fluxes through multitrophic groups. Taken together, legume addition and understory vegetation removal modify the patterns of soil CO2 emissions via changing nematode metabolic rates and re-shaping the energetic structure of soil food webs.
期刊：
Environmental Monitoring and Assessment,2023年195(12):1-17 ISSN：0167-6369
通讯作者：
Wan, DJ
作者机构：
[Wan, Da-juan; Huang, Jun-lin; Wang, Chen-ran; Chen, Jia-qi; Xiang, Yi-fan] Hunan Normal Univ, Coll Geog Sci, Changsha 410081, Peoples R China.;[Cao, Xue-ying] Changsha Univ, Rural Vitalizat Res Inst, Changsha 410022, Peoples R China.;[Ouyang, Ning-xiang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.
通讯机构：
[Wan, DJ ] H;Hunan Normal Univ, Coll Geog Sci, Changsha 410081, Peoples R China.
关键词：
Hunan Province;Paddy soil;Lead;Zinc;Spatial distribution characteristics;Parent materials
摘要：
This study aimed to investigate the distribution and migration characteristics of lead (Pb) and zinc (Zn) in paddy soils in Hunan Province, China. A total of 343 soil samples from 63 profiles were collected from typical regions. The concentration, spatial distribution, and migration behaviors of Pb and Zn in the paddy soils were examined. The results showed that (1) the concentration ranges of Pb and Zn in the surface layer were 17.62-114.07 mg/kg and 44.98-146.84 mg/kg, respectively. (2) The content was higher in the middle and lower reaches of the Xiangjiang River basin horizontally and exhibited shallow enrichment characteristics vertically. (3) Pb migration was weaker than Zn migration, and the parent material had the most significant influence on Pb and Zn content in the bottom soil layer. The research results will clarify the characteristics of Pb and Zn contents in paddy soils in Hunan Province, further understand the horizontal distribution and vertical migration and transformation characteristics of Pb and Zn contents in paddy soils, and provide basic data for scientific rice cultivation and safe food production.
摘要：
Allelopathy has been considered a good explanation for the successful invasion of some invasive plants. However, the real latitudinal and longitudinal allelopathic effects on native species have rarely been documented since many exotics have spread widely. We conducted a Petri dish experiment to determine the latitudinal and longitudinal allelopathic patterns of an invasive alligator weed (Alternanthera philoxeroides) on a common crop (Lactuca sativa) in China, and find what determines the allelopathic intensity. The results showed that the allelopathic effects of A. philoxeroides increased with the latitude while decreased with the longitude. This indicated that A. philoxeroides used its allelopathy to gain competitive advantages more in its recent invaded communities than that in its early invaded ones as A. philoxeroides is expanding from southeast China to northwest China. Furthermore, we found that the allelopathic intensity of A. philoxeroide was negatively correlated to the leaf contents of soluble carbohydrate (SC), carbon (C) and nitrogen (N), but that was positively correlated to the leaf contents of soluble protein (SP), free amino acids (FAA), plant polyphenol (PP), phosphorus (P) and potassium (K). These results suggested that the allelopathic intensity of A. philoxeroide was more determined by the limited P and K nutrients as well as the intermediate allelochemicals (SP, FAA, PP) rather than the unlimited C, N and SC. Thus, we can speculate that the negative or positive effects of plant aqueous extracts are a function of not only the extract concentrations but also the trade-offs between inhibition and promotion of all components in the extracts. Then we could reduce the allelopathic effects of A. philoxeroide by controlling the component contents in the plant tissues, by fertilization or other managements, especially in the plant recent invaded communities.
摘要：
Expose of cadmium (Cd) leads to severe leaf chlorosis and reducing nutrient uptake. It is unclear how plants responded to Cd stress in the roots, and its relation to the leaf chlorosis. Our results showed Cd disturbed the homeostasis of multiple nutrient element at different levels. The most reduced elements were Mn, Fe, with 96 %, 89 % decline in the leaves, that caused leaf chlorosis. The plants actively downregulated the expression of metal transporters to reduce Cd uptake, but consequently reducing Fe and Mn uptake. Moreover, Cd stress promoted the formation of iron plaque and significantly reduced the exchangeable ions on root surface. Importantly, ethylene plays an essential role in regulating iron plaque formation and the existent forms of Cd. Blocking ethylene biosynthesis significantly increased exchangeable Cd on the root surface and decreased the percentage of iron oxides bound Cd, thus leading to increase of Cd in the shoots. Above all, our results revealed plants actively control the expression of metal transporter and the ethylene-dependent iron plaque formation to reduce Cd uptake, but sacrificed iron nutrition. The mechanism of sequester Cd on rhizosphere by ethylene in response to Cd stress may provide guidelines for the mitigation of Cd accumulation in rice via ethylene-dependent rhizosphere regulation.
通讯机构：
[Jiangchi Fei] C;College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China<&wdkj&>National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Changsha 410128, China
作者机构：
[Ke, Yong; Du, Jiali; Wang, Yunyan; Cao, Junjie; Min, Xiaobo; Zhang, Limin; Xu, Hui; Yu, Lin; Luo, Yongjian] Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.;[Ke, Yong; Wang, Yunyan; Min, Xiaobo] Chinese Natl Engn Res Ctr Control & Treatment Heav, Changsha 410083, Peoples R China.;[Ke, Yong; Wang, Yunyan; Min, Xiaobo] Water Pollut Control Technol Key Lab Hunan Prov, Changsha 410004, Peoples R China.;[Yao, Liwei] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.
通讯机构：
[Liwei Yao] A;[Yunyan Wang] W;Authors to whom correspondence should be addressed.<&wdkj&>College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Water Pollution Control Technology Key Laboratory of Hunan Province, Changsha 410004, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>School of Metallurgy and Environment, Central South University, Changsha 410083, China<&wdkj&>Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
摘要：
Sulfide precipitation has been widely applied to remove arsenic from acidic wastewater containing As(III) and As(V), due to its simple process and high efficiency. However, the characteristics and composition of the precipitates are also of importance for its further treatment and disposal. To explore the characteristics of elemental S formed by reduction and the combined form of the generated S and As2S3, the characteristics of precipitates sulfurized from As(III) and As(V) and the effects of temperature, the S(-II) to As ratio (S/As), Cl- concentration (c(Cl-)), and the volume fraction of H2SO4 (phi(H2SO4(v))) on the sulfurization of As(III) and As(V) were investigated in detail. The results showed that the contents of As and S were 60.37% and 39.73% in precipitate-As(III), while they accounted for 47.46% and 52.64% in precipitate-As(V); both precipitate-As(III) and precipitate-As(V) were mainly composed of amorphous As2S3, while the latter contained elemental S. Temperature and S(-II)/As(III) slightly affected the sulfurization process of As(III), while for As(V), as the temperature increased, the content of As2S3 in precipitate-As(V) increased significantly. Additionally, with the S(-II)/As(V) increasing, the content of A(2)S(3) increased continuously. This study provides a further clarification of the specific composition and structure of the complex precipitates of arsenic sulfide, which will benefit the efficient stabilization of the arsenic sulfide sludge.
作者机构：
[Guan, Chunyun; Zhang, Yin; Chen, Can; Huang, Huang; Xu, Ying] Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.;[Guan, Chunyun; Zhang, Yin; Chen, Can; Huang, Huang] Hunan Engn Res Ctr Rice Field Ecol Planting & Bree, Changsha 410128, Peoples R China.;[Li, Zhengyou] Fisheries Res Inst Guizhou Prov, Guiyang 550025, Peoples R China.;[Luo, Jun] Congjiang Agr & Rural Bur Guizhou Prov, Congjiang 557400, Peoples R China.;[Ren, Bo] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.
通讯机构：
[Huang Huang] C;College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Engineering Research Center of Rice Field Ecological Planting and Breeding, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
rice-fish-duck symbiosis system;globally important agricultural heritage system;value;technology;challenge;countermeasure
摘要：
The Chinese rice-fish-duck symbiosis system is one of the globally important agricultural heritage systems, with a history of nearly a thousand years. It embodies the wisdom of the Chinese ancestors and has huge comprehensive value, which has extremely important references for the sustainable development of agriculture. The technological core for the rice-fish-duck symbiosis system lies in the selection of rice, fish, and duck varieties and the coupling of agricultural operation time. In the process of modern agriculture, many varieties with high comprehensive benefits have also been applied to the rice-fish-duck system, and the rice-fish-duck model has been further developed. What is worrying is that the transfer of rural labor, the promotion of modern agricultural technology, the low degree of marketization and industrialization, the weakening of cultural awareness, and the change in climate have posed huge threats and challenges to the traditional Chinese rice-fish-duck system. The protection and development of the system are urgently needed. Therefore, we recommend delimiting active protection areas, establishing scientific research bases, improving relevant systems, developing rural tourism markets, and innovating farming technology, which also provide guidance for protecting and developing other agricultural cultural heritages.
作者机构：
[Hu, Ang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China.;[Wang, Jianjun; Hu, Ang; Meng, Fanfan] Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;[Wang, Jianjun; Meng, Fanfan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Tanentzap, Andrew J.] Trent Univ, Sch Environm, Ecosyst & Global Change Grp, Peterborough, ON K9L 0G2, Canada.;[Tanentzap, Andrew J.] Univ Cambridge, Dept Plant Sci, Ecosyst & Global Change Grp, Cambridge CB2 3EA, England.
通讯机构：
[Jianjun Wang] S;State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academic of Sciences, Nanjing210008, China<&wdkj&>University of Chinese Academy of Sciences, Beijing100049, China
关键词：
dark matter;microbes;dissolved organic matter;global change
关键词：
Surface ion imprinting;support;heavy metal ions;adsorption
摘要：
Surface ion-imprinting technology (SIIT) is a novel and effective alternative to conventional methods of preparing ion-imprinted polymers. SIIT involves the coating of support materials with a polymeric layer that selectively binds with imprinted metal ions, particularly heavy metal ions. Given its specificity, predictability, and stability, SIIT has been quickly adopted in ion detection, separation, enrichment, and sensing. Here, building on the latest advances in this emerging new technology, we carried out a systematic review to summarize the 1) principles and basic components of surface ion-imprinted polymers (SIIPs); 2) preparations, properties, advantages, and disadvantages of three types of SIIP supporting materials, including inorganic (minerals, carbonaceous materials, metal oxides), organic, and composite (organic/organic, organic/inorganic, inorganic/inorganic) supports; 3) current applications of SIIT, and 4) future challenges and opportunities related to SIIT. Finally, perspectives and future research are discussed to address the pressing need for the development of SIIT for heavy metal ion treatment.
摘要：
Electrontransfer (ET) is the essence of most biogeochemical processesrelated to element cycling and contaminant attenuation, whereas ETbetween different minerals and the controlling mechanism remain elusive.Here, we used surface-associated Fe-(II) as a proxy to explore ET betweenreduced nontronite NAu-2 (rNAu-2) and Fe (hydr)-oxides in their coexistingsystems. Results showed that ET could occur from rNAu-2 to ferrihydritebut not to goethite, and the ET amount was determined by the numberof reactive sites and the reduction potential difference between rNAu-2and ferrihydrite. ET proceeded mainly through the mineral-mineralinterface, with a negligible contribution of dissolved Fe2+/Fe3+. Control experiments by adding K+ andincreasing salinity together with characterizations by X-ray diffraction,scanning electron microscopy/energy-dispersive spectrometry, and atomicforce microscopy suggested that ferrihydrite nanoparticles insertedthe interlayer space in rNAu-2 where structural Fe-(II) in rNAu-2 transferredelectrons mainly through the basal plane to ferrihydrite. This studyimplicates the occurrence of ET between different redox-active mineralsthrough the mineral-mineral interface. As minerals at differentreduction potentials often coexist in soils/sediments, the mineral-mineralET may play an important role in subsurface biogeochemical processes. Electron transfer from Fe-(II)-bearingclay minerals to Fe(hydr)-oxides proceeds mainly through the mineral-mineral interface,with the interior structural Fe-(II) and expandable interlayer spacein clay minerals serving as the major electron reservoir and reactionsite, respectively.
关键词：
Lead-acid battery;Low temperature alkaline smelting;FeO-SiO 2-CaO-Na 2 O smelting system;Bath smelting;Lead recovery
摘要：
Recycling lead from waste lead-acid batteries has substantial significance in environmental protection and economic growth. Bearing the merits of easy operation and large capacity, pyrometallurgy methods are mostly used for the regeneration of waste lead-acid battery (LABs). However, these processes are generally operated at the temperature higher than 1300 degrees C. To shorten the energy consumption, a novel pyrometallurgy process which consisted of low temperature alkaline and bath smelting was proposed in this work. The reduction of lead and smelting of slag system are the key factors determine the energy consumption. Thermodynamic calculation suggested that the addition of Na2CO3 can make the reduction of PbSO4 spontaneously at the temperature higher than 288 degrees C (PbSO4 -> PbCO3 -> PbO -> Pb), while direct reduction of PbSO4 necessitated the temperature higher than 1499 degrees C (PbSO4 -> PbO -> Pb). To achieve the efficient reduction of PbSO4, the molar ratios of C/PbSO4 and Na2CO3/PbSO4 should be higher than 0.5 and 1.0, respectively. Meanwhile, a new smelting system (i.e., FeOSiO2-CaO-Na2O) was established in the presence of Na2CO3. Phases with low melting temperatures, such as NaFe2O3, Na2FeSiO4, Na2Ca2Si2O7, Na14Fe6O16 and Na0.5FeO2, were formed. The melting temperature of Fe-SiCa-Na system was lowered to 1050 degrees C at the mass dosage of Na2CO3 at 30%. Recovery of lead under various reduction conditions were systematically evaluated. Under optimum operational conditions, i.e., the dosages of C and Na2CO3 at 10% and m(actual)/m(theory) ratio of 1.3 (all in mass), smelting temperature of 1050 degrees C, and smelting time of 75 min, respectively, the lead recovery efficiency reached >98.0%. Moreover, this method has been successfully applied for the industrial recovery of lead at the scale of 200, 000 tons annually since 2019. Taken together, this method is robust for recovery of lead from the waste LABs and is helpful for building the resource-conserving society.
摘要：
In recent years, carbon-based materials catalyzing peroxymonosulfate (PMS) for green degradation of persistent or-ganic pollutants have attracted increasing attention. However, PMS activation by hydrochar composite (e.g. hydrochar-montomorillonite) has rarely been investigated. Herein, a simple preparation, low-cost and eco-friendly catalyst of hydrochar-montmorillonite composite (HC-Mt) was prepared to firstly catalyze PMS for the degradation of dicamba (DIC). The as-prepared HC-Mt showed a remarkably better catalyzing performance for PMS than pure hydrochar (HC) due to its good physicochemical characteristics and abundant oxygen-containing groups. Further-more, the electron spin resonance (ESR) and quenching tests revealed that active species such as SO4 center dot-, center dot OH and O2 center dot- all participated in the degradation process. DIC sites on C6, Cl 10, and O15 exhibited higher reactivity according to the density functional theory (DFT) calculation, which were easily attacked by active species. The DIC degradation mainly occurred via hydroxyl substitution, decarboxylation, oxidation and ring-cleavage and finally most of the inter-mediates were mineralized into CO2 and H2O. Finally, the phytotoxicity assessment was measured by the germination growth situation of tobacco and mung beans in the presence of DIC (with or without treatment by HC-Mt/PMS). The result showed that HC-Mt/PMS could significantly reduce the phytotoxicity of DIC to crops, suggesting that catalyzing PMS using HC-Mt was environmentally friendly. Therefore, this work did not only provide a novel catalyzing PMS strategy using hydrochar composite for wastewater treatment, but also give a new idea for herbicide phytotoxicity management.
通讯机构：
[Hong-Yuan Zeng; Ai-Ping Wu] A;Authors to whom correspondence should be addressed.<&wdkj&>Hunan Institute of Microbiology, Changsha 410009, China<&wdkj&>Authors to whom correspondence should be addressed.<&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
摘要：
Water level rise is considered an environmental filter for the growth and reproduction of aquatic plants in lakes. Some emergent macrophytes can form floating mats, enabling them to escape from the negative effects of deep water. However, an understanding of which species can be uprooted and form floating mats easily and what factors affect these tendencies remains greatly elusive. We conducted an experiment to determine whether the monodominance of Zizania latifolia in the emergent vegetation community in Lake Erhai was related to its floating mat formation ability and to try to find the reasons for its floating mat formation ability during the continuous increase in water level over the past few decades. Our results showed that both the frequency and biomass proportion of Z. latifolia were greater among the plants on the floating mats. Furthermore, Z. latifolia was more likely to be uprooted than the other three previously dominant emergent species due to its smaller angle between the plant and the horizontal plane, rather than the root:shoot or volume:mass ratios. The dominance of Z. latifolia in the emergent community in Lake Erhai is due to its easier ability to become uprooted, allowing it to outperform other emergent species and become the single dominant emergent species under the environmental filter of deep water. The ability to uproot and form floating mats may be a competitive survival strategy for emergent species under the conditions of continuous significant water level rise.
