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Irrigation and nitrogen fertiliser optimisation in protected vegetable fields of northern China:Achieving environmental and agronomic sustainability
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作者 Bingqian Fan Yitao Zhang +8 位作者 Owen Fenton Karen Daly Jungai Li Hongyuan Wang Limei Zhai Xiaosheng Luo Qiuliang Lei Shuxia Wu Hongbin Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1022-1033,共12页
Globally,sub-optimal use of nitrogen (N) fertiliser and elevated N irrigation groundwater have led to high leached nitrate (NO_(3)^(–)) losses from protected vegetable field systems.Optimising fertiliser and irrigati... Globally,sub-optimal use of nitrogen (N) fertiliser and elevated N irrigation groundwater have led to high leached nitrate (NO_(3)^(–)) losses from protected vegetable field systems.Optimising fertiliser and irrigation management in different soil types is crucial to reduce future N loads from such systems.The present 4-year study examined leached N loads from lysimeter monitoring arrays set up across 18 protected vegetable system sites encompassing the dominant soil types of northern China.The treatments applied at each field site were:1) a high N and high irrigation input treatment (HNHI);2) a low N but high irrigation input treatment (LNHI) and 3) a low N with low irrigation input treatment (LNLI).Results showed that the mean annual leached total nitrogen loads from the HNHI,LNHI and LNLI treatments were 325,294 and 257 kg N ha^(–1) in the fluvo-aquic soil,114,100 and 78 kg N ha^(–1) in the cinnamon soil and 79,68 and 57 kg N ha^(–1) in the black soil,respectively.The N dissolved in irrigation water in the fluvo-aquic soil areas was 8.26-fold higher than in the cinnamon areas.A structural equation model showed that N fertiliser inputs and leaching water amounts explained 14.7 and 81.8%of the variation of leached N loads,respectively.Correspondingly,reducing irrigation water by 21.5%decreased leached N loads by 20.9%,while reducing manure N and chemical N inputs by 22 and 25%decreased leached N loads by only 9.5%. This study highlights that protected vegetable fields dominated by fluvo-aquic soil need management to curtail leached N losses in northern China. 展开更多
关键词 agriculture water quality NITRATE GROUNDWATER irrigation management
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Determining indoor air quality and identifying the origin of odour episodes in indoor environments 被引量:14
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作者 Eva Gallego Xavier Roca +1 位作者 Jose Francisco Perales Xavier Guardino 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期333-339,共7页
A methodology for identifying volatile organic compounds (VOCs) and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive o... A methodology for identifying volatile organic compounds (VOCs) and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive odorous and/or discomfort episodes. Glass multi-sorbent tubes are connected to the pump samplers for the retention of VOC. The analysis is performed by automatic thermal desorption (ATD) coupled with gas chromatography-mass spectrometry (GC/MS). This methodology can be applied in cases of sick building syndrome (SBS) evaluation, in which building occupants experience a series of varied symptoms that appear to be linked to time spent in the building. Chemical pollutants concentrations (e.g., VOC) have been described to contribute to SBS. To exemplify the methodology, a qualitative determination and an evaluation of existing VOC were performed in a dwelling where the occupants experienced the SBS symptoms. Higher total VOC (TVOC) levels were detected during episodes in indoor air (1.33 ±1.53 mg/m^3) compared to outdoor air (0.71± 0.46 mg/m^3). The concentrations of individual VOCs, such as ethanol, acetone, isopropanol, 1-butanol, acetic acid, acetonitrile and 1-methoxy-2-propanol, were also higher than the expected for a standard dwelling. The external source of VOC was found to be an undeclared activity of storage and manipulation of solvents located at the bottom of a contiguous building. 展开更多
关键词 indoor air thermal desorption TVOC VOC sick building syndrome
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Use and application of CFC-11,CFC-12,CFC-113 and SF6 as environmental tracers of groundwater residence time:A review 被引量:7
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作者 L.A. Chambers D.C. Gooddy A.M. Binley 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第5期1643-1652,共10页
Groundwater residence time is a fundamental property of groundwater to understand important hydrogeological issues,such as deriving sustainable abstraction volumes,or,the evolution of groundwater quality.The anthropog... Groundwater residence time is a fundamental property of groundwater to understand important hydrogeological issues,such as deriving sustainable abstraction volumes,or,the evolution of groundwater quality.The anthropogenic trace gases chlorofluorocarbons (CFC-11,CFC-12 and CFC-113) and sulphur hexafluoride (SF6) are ideal in this regard because they have been released globally at known rates and become dissolved in groundwater following Henry’s Law,integrating over large spatial (global) and temporal (decades) scales.The CFCs and SF6 are able to date groundwater up to w100 years old with the caveat of certain simplifying assumptions.However,the inversion of environmental tracer concentrations (CFCs and SF6) to derive groundwater age rests on the accurate determination of groundwater recharge parameters,namely temperature,elevation,salinity and excess air,in addition to resolving the potential for contamination,degradation and unsaturated zone effects.This review explores the fundamentals of CFC-11,CFC-12,CFC-113 and SF6 as environmental tracers of groundwater age and recommends complementary techniques throughout.Once this relatively simple and inexpensive technique has been used to determine initial concentrations at the recharge zone,setting the groundwater dating ‘clock’ to zero,this review then explores the meaning of groundwater ‘age’ in relation to measured environmental tracer concentrations.It is shown that the CFCs and SF6 may be applied to a wide-range of hydrogeological problems and suggests that environmental tracers are particularly powerful tools when integrated with numerical flow and transport models. 展开更多
关键词 HYDROGEOLOGY Environmental tracers GROUNDWATER DATING
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Is environmental antimony a potential health problem? 被引量:1
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作者 John G. Farmer Joanna M. Cloy +2 位作者 Margaret C. Graham Angus B. MacKenzie Gordon T. Cook 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期68-69,共2页
关键词 环境污染 人体健康 有毒元素
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Environmental Benefits for Phase-Out HCFC-22 in the Residential Air-Conditioner Sector in China 被引量:1
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作者 Tingting Wan Yanwei Dou +4 位作者 Lei Wang Lirong Yang Xiaofang Zhou Dan Wan Jianxin Hu 《Advances in Climate Change Research》 SCIE 2011年第2期86-92,共7页
China is the largest producer and consumer of hydrochlorofluorocarbons (HCFCs), and the production of HCFC-22 accounts for more than 80% of all HCFCs. This paper concentrates on the residential air-conditioner indus... China is the largest producer and consumer of hydrochlorofluorocarbons (HCFCs), and the production of HCFC-22 accounts for more than 80% of all HCFCs. This paper concentrates on the residential air-conditioner industry and analyzes the environmental benefits of accelerating the phase-out of HCFC-22 in China. According to the comparison of the baseline and phase-out scenarios of HCFC-22, the findings show that using HC-290 (propane) as a refrigerant alternative will directly reduce the greenhouse effect, and indirectly reduce the emission of greenhouse gases due to a reduction in the electricity consumption. The comparison of two scenarios of HC-290 and HFC-410A refrigerant alternatives shows that the use of HC-290 refrigerant will produce significantly higher environmental benefits than the HFC-410A refrigerant. 展开更多
关键词 HCFC-22 HFC-410A HC-290 residential air-conditioner GWP ODP
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Saltmarsh vegetation and social environment influence flexible seasonal vigilance strategies for two sympatric migratory curlew species in adjacent coastal habitats 被引量:1
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作者 Jing Zhang Hang Zhang +4 位作者 Yu Liu Huw Lloyd Jianqiang Li Zhengwang Zhang Donglai Li 《Avian Research》 CSCD 2021年第3期327-337,共11页
Background:Animals need to adjust their vigilance strategies when foraging between physically contrasting veg-etated and non-vegetated habitats.Vegetated habitats may pose a greater risk for some if vegetation charact... Background:Animals need to adjust their vigilance strategies when foraging between physically contrasting veg-etated and non-vegetated habitats.Vegetated habitats may pose a greater risk for some if vegetation characteristics function as a visual obstruction but benefit others if they serve as protective shelter.Variation in group size,presence of similar species,along with variation in environmental conditions and anthropogenic disturbance can also influence vigilance investment.Methods:In this study,we quantified the vigilance behaviour of two large-bodied,sympatric migratory curlew species-Far Eastern Curlew(Numenius madagascariensis)and Eurasian Curlew(N.arquata)-in vegetated Suaeda salsa saltmarsh and non-vegetated mudflat habitat in Liaohekou National Nature Reserve,China.We used linear mixed models to examine the effects of habitat type,season,tide time,flock size(conspecific and heterospecific),and human disturbance on curlew vigilance investment.Results:Both species spent a higher percentage of time under visual obstruction in S.salsa habitat compared to mudflat habitat but in response,only Far Eastern Curlew increased their percentage of vigilance time,indicating that visual obstruction in this habitat is only a concern for this species.There was no evidence that S.salsa vegetation served as a form of cryptic background colouration since neither species decreased their vigilance effect in S.salsa habitat in spring compared to the autumn migration season.The effect of curlew social environment(i.e.flock size)was habitat dependent since percentage of vigilance time by curlews in saltmarsh increased with both the number of individual curlews and number of other birds present,but not in mudflat habitat.Conclusions:We conclude that both migratory curlew species exhibit a flexible vigilance adjustment strategy to cope with the different environmental and social conditions of adjacent and sharply contrasting coastal habitats,and that the trade-off between the risks of foraging and the abundance of prey may be a relatively common phenom-enon in these and other shorebird populations. 展开更多
关键词 Flock size Foraging behaviour Linear mixed models Numenius curlews Suaeda salsa saltmarsh VIGILANCE Yellow Sea
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STUDIES ON ENVIRONMENTAL BACKGROUND VALUES IN CHINA
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作者 缪天成 王惠琪 郑春江 《Chinese Geographical Science》 SCIE CSCD 1991年第4期16-25,共10页
An investigation on environmental background values was made in an area of about 1,140,000 km2, which included temperate and subtropical zones of China. The environmental background values of 142 soil environment unit... An investigation on environmental background values was made in an area of about 1,140,000 km2, which included temperate and subtropical zones of China. The environmental background values of 142 soil environment units, 18 main soil types, 87 surface water environment units, 8 aquatic organism environment units and 20 underground water environment units were obtained. The rules, causes and effecting factors of regional differentiation of the environmental background values were deduced from over 200,000 various data. 展开更多
关键词 SOIL water ORGANISM ENVIRONMENTAL BACKGROUND VALUE
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Building Resilience Through Disaster Waste Management——UN Environment's Experiences and Approaches
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作者 PRADHAN Mahesh XU Qing 《工程科学与技术》 EI CAS CSCD 北大核心 2018年第3期15-23,共9页
Integrating disaster waste issue is a critical component of making humanitarian action fit for the future,anticipating global risks and challenges such as increased vulnerability due to climate change and environmenta... Integrating disaster waste issue is a critical component of making humanitarian action fit for the future,anticipating global risks and challenges such as increased vulnerability due to climate change and environmental degradation.This requires a fundamental shift towards a model that not only strengthens the response to crises but also learns and adapts in order to anticipate and act before such waste garnered.This article conducted analyses on the characteristics of disasters in the past two decades.Uncertainties confound disaster waste management,including the timing and magnitude of each disaster,and the amounts and types of waste that will be generated.For these reasons alone,disaster waste management must be an integral part of development planning and processes.Making 10 years since the 2008 Wenchuan earthquake,this article highlights that disaster waste management is not only debris clearance or waste management following a disaster,but also includes prevention and pre-disaster preparedness aspects in terms of enhancing resilience of local communities.Such"mainstreaming,"ensures that disaster waste management(DWM)will be treated as a priority issue,on an ongoing basis.Based on UN Environment's experiences and approaches,this paper emphasises that preparedness is the key,and that priority should be accorded to integrating disaster contingency planning in national and city level waste management strategies as well as mainstreaming waste management issues within broader disaster preparedness and response plans and actions.It is envisaged that the issues presented and the gaps identified in this paper will provide a basis for future comprehensive and cohesive research on disaster waste management.In turn,this research can lead to better preparedness and response on disaster waste management. 展开更多
关键词 disaster waste disaster risk reduction waste management Sendai Framework
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Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea
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作者 Ran Ye Chunying Ge +6 位作者 Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin Yanhong Cai Yuejun Fei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第6期100-110,共11页
Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This study provided insights into the relationships ... Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China Sea.Results demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in summer.As for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,respectively.They exhibited strong indications in response to environmental changes.These findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species. 展开更多
关键词 ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province
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Phytoplanktonic biogeography in the subtropical coastal waters,East China Sea along intensive anthropogenic stresses: roles of environmental versus spatial factors
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作者 Ran Ye Haibo Zhang +5 位作者 Yige Yu Qing Xu Dandi Shen Min Ren Lian Liu Yanhong Cai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期103-113,共11页
Understanding the relative roles of local environmental effects and spatial effects on phytoplankton community is of essential importance to study the biogeography of them at regional scale. However, the determinants ... Understanding the relative roles of local environmental effects and spatial effects on phytoplankton community is of essential importance to study the biogeography of them at regional scale. However, the determinants that driving the biogeography of phytoplankton communities in the coastal area of northern Zhejiang still remained unclear. We surveyed phytoplankton community compositions in water columns associated with environmental and spatial influences across five subzones that geographically covering this region over four seasons. Diatoms and dinoflagellates were recorded as the main dominant groups and Coscinodiscus oculs-iridis, Coscinodiscus jonesianus, and Skeletonema costatum, were identified as the major abundant species existing in all seasons.Spatially structured environmental conditions, rather than pure spatial or environmental factors, substantially shaped the biogeography of phytoplankton community, with the former mainly comprised of water temperature,dissolved oxygen, phosphate, pH, and salinity, and the latter referring to a non-negligible factor. This study was the first integrated research that combining environmental filtering with spatial factors in structuring phytoplankton communities at a complete tempo-spatial scale. Our results may facilitate to the further study of harmful algal blooms early-warning in this region. 展开更多
关键词 biogeography of phytoplankton community environmental factors spatial factors coastal area of northern Zhejiang
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Pleistocene Birds of Gruta da Furninha (Peniche-Portugal): A Paleontological and Paleoenvironmental Aproach
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作者 Silverio Domingues Figueiredo Pedro Proenga Cunha +2 位作者 Femanda Sousa Telmo Pereira Americo Rosa 《Journal of Environmental Science and Engineering(A)》 2017年第10期502-509,共8页
The cave-site of Gruta da Furninha is a coastal karstic cavity. In the late 19th century, excavation of the sedimentary infill of the cave allowed the identification of two lithostratigraphic units: a Holocene one do... The cave-site of Gruta da Furninha is a coastal karstic cavity. In the late 19th century, excavation of the sedimentary infill of the cave allowed the identification of two lithostratigraphic units: a Holocene one dominated by sands, containing human bones and a Neolithic industry; and a Late Pleistocene one, containing a diverse set of fossils set and Paleolithic artifacts. This study mainly focuses on taphonomic and palaeoenvironmental data concerning the Pleistocene bird bones that were collected from six layers (at 11 m and 6.7 m asl). A main result of this study was the discovery of a left humerus fragment, with osteological features of the Alcidae family; from comparison with upper arms of distinct species of this family, it was concluded that this fossil belongs to Penguin impennis. The Pleistocene birds of the Furninha cave were also compared with the avifauna that currently occurs in the region of Peniche peninsula and a climate and environmental interpretation of the Pleistocene fossiliferous set is provided. 展开更多
关键词 BIRDS PLEISTOCENE marine caves Portugal.
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水环境中全氟和多氟烷基物质(PFAS)的分析技术与分布特征
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作者 车晓佳 葛林科 +4 位作者 杨妍 郑金帅 张蓬 贺广凯 马宏瑞 《中国环境监测》 CAS CSCD 北大核心 2024年第6期28-44,共17页
新污染物全氟和多氟烷基物质(PFAS)因具有持久性、长距离迁移性、生物积累性和生物毒性而受到广泛关注。水环境是PFAS重要的汇,相关学者已对其污染状况开展了大量研究。通过梳理相关文献发现,目前的研究在PFAS分析技术、分布特征及其在... 新污染物全氟和多氟烷基物质(PFAS)因具有持久性、长距离迁移性、生物积累性和生物毒性而受到广泛关注。水环境是PFAS重要的汇,相关学者已对其污染状况开展了大量研究。通过梳理相关文献发现,目前的研究在PFAS分析技术、分布特征及其在水和沉积物之间的分配机理方面有了一些突破。鉴于此,总结了水环境中PFAS的前处理和检测技术,讨论了其在国内外地表水环境中的空间分布及污染特征,着重评述了PFAS在固相基质中的吸附机理及影响因素,最后展望了PFAS类新污染物的研究方向。 展开更多
关键词 全氟和多氟烷基物质 前处理 分析方法 分布特征 影响因素
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A dicistrovirus increases pupal mortality in Spodoptera frugiperda by suppressing protease activity and inhibiting larval diet consumption
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作者 Meixue Sun Tong Li +6 位作者 Yingjie Liu Kenneth Wilson Xingyu Chen Robert I.Graham Xianming Yang Guangwei Ren Pengjun Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2723-2734,共12页
Understanding interactions between viruses and their hosts is conducive to enabling better application of viruses as biocontrol agents.Certain viruses carried by parasitic wasps enhance the parasitic efficiency of was... Understanding interactions between viruses and their hosts is conducive to enabling better application of viruses as biocontrol agents.Certain viruses carried by parasitic wasps enhance the parasitic efficiency of wasp-larvae by protecting them against the immune system of their Lepidopteran host.However,the relationship between prey pests and viruses found in predatory natural enemies remains unclear.Herein,we report the interaction between Arma chinensis virus-1(AcV-1),originally isolated from a predatory natural enemy,Arma chinensis(Hemiptera:Pentatomidae),and one of its prey species,Spodoptera frugiperda(Lepidoptera:Noctuidae).The results showed that the AcV-1 virus appeared harmful to the novel host S.frugiperda by inhibiting larval diet consumption and increasing pupal mortality.Meanwhile,sequencing data indicated that the virus altered the gene expression profiles of S.frugiperda.KEGG analysis showed that the proteasome and phagosome pathways related to protein degradation and immune response were significantly enriched.Although the expression levels of digestive enzyme genes did not change significantly,the total protease activity of AcV-1 virus-positive individuals was significantly decreased,suggesting that the virus inhibited diet consumption of S.frugiperda via the down-regulation of digestive enzyme activities.These results indicate that a virus initially isolated in a predatory natural enemy can decrease the fitness of its prey species.The virus was found to impact the host proteasome and phagosome pathways related to protein degradation and immunity,providing a potential mechanism to enhance controlling efficiency. 展开更多
关键词 Arma chinensis virus-1 diet consumption FITNESS TRANSCRIPTOME protease activity
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Intelligent Fractional-Order Controller for SMES Systems in Renewable Energy-Based Microgrid
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作者 Aadel M.Alatwi Abualkasim Bakeer +3 位作者 Sherif A.Zaid Ibrahem E.Atawi Hani Albalawi Ahmed M.Kassem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1807-1830,共24页
An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.Howe... An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES. 展开更多
关键词 Fractional-order proportional integral(FOPI) intelligent controller renewable energy resources superconducting magnetic energy storage OPTIMIZATION
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On the Range of Action of Adult Culex pipiens s.l.
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作者 Maria da Conceição Proença Maria Teresa Rebelo 《Journal of Biosciences and Medicines》 2024年第3期113-121,共9页
Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans... Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures. 展开更多
关键词 Mosquito Fly Distance Vector-Borne Diseases Culex pipiens s.l. Geographic Information Systems
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Microplastic Impacts on Greenhouse Gases Emissions in Terrestrial Ecosystems
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作者 Tazeen Fatima Khan M. M. Golam Rabbani 《Open Journal of Soil Science》 2024年第1期64-80,共17页
Microplastics can influence global climate change by regulating the emissions of greenhouse gases from different ecosystems. The effects of microplastics in terrestrial ecosystems are still not well studied particular... Microplastics can influence global climate change by regulating the emissions of greenhouse gases from different ecosystems. The effects of microplastics in terrestrial ecosystems are still not well studied particularly greenhouse gases emissions. Thus, we conducted a laboratory experiment over a period of 90 days with two types of microplastics (differing in their chemical structure), high density polyethylene (HDPE) and low density polyethylene (LDPE), which were applied to the soil at a rate of 0% to 0.1% (w/w). The overarching aim was to investigate the effects of microplastic type, microplastic concentration and days of exposure on greenhouse gases emissions. We also used original and artificially weathered microplastics (the same HDPE and LDPE) to make a comparison of greenhouse gases emissions between the original microplastics treated soils and the soils treated with weathered microplastics. Our findings showed that HDPE and LDPE microplastics significantly increased the emissions of greenhouse gases from the soil than that of the control soils. Emissions were increased with the increases in the level of microplastic in the soil. The weathered microplastic emitted greater quantity of greenhouse gases compared to that of the original microplastics. In contrast to a low initial emission quantity, the emissions were gradually increased at the termination of the experiment. Our experiment on the emissions of greenhouse gases from the soil vis-à-vis microplastic additions indicated that the microplastic increased the emissions of greenhouse gases in terrestrial ecosystems, and pervasive microplastic impacts may have consequences for the global climate change. Greenhouse gases emissions from the soil not only depend on the type and concentration of the microplastic, but also on the days of exposure to the microplastic. 展开更多
关键词 Microplastic Climate Change Greenhouse Gas TYPE CONCENTRATION
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The sudden ocean warming and its potential influences on earlyfrozen landfast ice in the Prydz Bay, East Antarctica
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作者 Haihan Hu Jiechen Zhao +4 位作者 Jingkai Ma Igor Bashmachnikov Natalia Gnatiuk Bo Xu Fengming Hui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期65-77,共13页
The ocean conditions beneath the ice cover play a key role in understanding the sea ice mass balance in the polar regions.An integrated high-frequency ice-ocean observation system,including Acoustic Doppler Velocimete... The ocean conditions beneath the ice cover play a key role in understanding the sea ice mass balance in the polar regions.An integrated high-frequency ice-ocean observation system,including Acoustic Doppler Velocimeter,Conductivity-Temperature-Depth Sensor,and Sea Ice Mass Balance Array(SIMBA),was deployed in the landfast ice region close to the Chinese Zhongshan Station in Antarctica.A sudden ocean warming of 0.14℃(p<0.01)was observed beneath early-frozen landfast ice,from(−1.60±0.03)℃during April 16-19 to(−1.46±0.07)℃during April 20-23,2021,which is the only significant warming event in the nearly 8-month records.The sudden ocean warming brought a double rise in oceanic heat flux,from(21.7±11.1)W/m^(2) during April 16-19 to(44.8±21.3)W/m^(2) during April 20-23,2021,which shifted the original growth phase at the ice bottom,leading to a 2 cm melting,as shown from SIMBA and borehole observations.Simultaneously,the slowdown of ice bottom freezing decreased salt rejection,and the daily trend of observed ocean salinity changed from+0.02 d^(-1) during April 16-19,2021 to+0.003 d^(-1) during April 20-23,2021.The potential reasons are increased air temperature due to the transit cyclones and the weakened vertical ocean mixing due to the tide phase transformation from semi-diurnal to diurnal.The high-frequency observations within the ice-ocean boundary layer enhance the comprehensive investigation of the ocean’s influence on ice evolution at a daily scale. 展开更多
关键词 sudden ocean warming oceanic heat flux landfast ice Zhongshan Station in-situ observation
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Efficient People Detection with Infrared Images
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作者 Maria da Conceição Proença 《Journal of Computer and Communications》 2024年第4期31-39,共9页
This work focuses on the problem of monitoring the coastline, which in Portugal’s case means monitoring 3007 kilometers, including 1793 maritime borders with the Atlantic Ocean to the south and west. The human burden... This work focuses on the problem of monitoring the coastline, which in Portugal’s case means monitoring 3007 kilometers, including 1793 maritime borders with the Atlantic Ocean to the south and west. The human burden on the coast becomes a problem, both because erosion makes the cliffs unstable and because pollution increases, making the fragile dune ecosystem difficult to preserve. It is becoming necessary to increase the control of access to beaches, even if it is not a popular measure for internal and external tourism. The methodology described can also be used to monitor maritime borders. The use of images acquired in the infrared range guarantees active surveillance both day and night, the main objective being to mimic the infrared cameras already installed in some critical areas along the coastline. Using a series of infrared photographs taken at low angles with a modified camera and appropriate filter, a recent deep learning algorithm with the right training can simultaneously detect and count whole people at close range and people almost completely submerged in the water, including partially visible targets, achieving a performance with F1 score of 0.945, with 97% of targets correctly identified. This implementation is possible with ordinary laptop computers and could contribute to more frequent and more extensive coverage in beach/border surveillance, using infrared cameras at regular intervals. It can be partially automated to send alerts to the authorities and/or the nearest lifeguards, thus increasing monitoring without relying on human resources. 展开更多
关键词 Beach Overload People Counting Border Control People Detection Deep Learning Methods Remote Surveillance
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Exploring Metal Based Nanoparticles for Boosting Plant Tolerance to Heavy Metals and Trace Element Contamination
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作者 Abdul Ghafoor Maria Latif +3 位作者 Shafaqat Ali Muhammad Munir Muhammad Naeem Sattar Mohammed Ali Alshehri 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期2683-2705,共23页
Heavy metal pollution in agricultural soils is a significant challenge for global food production and human health with the increasing industrialization and urbanization.There is a concern about introducing innovative ... Heavy metal pollution in agricultural soils is a significant challenge for global food production and human health with the increasing industrialization and urbanization.There is a concern about introducing innovative techni-ques that are eco-friendly,cost-effective,and have the potential to alleviate metals,enhance crop growth,and pro-tect plants against various environmental threats.For this,nanotechnology is one of the promising solutions having various applications in almost everyfield of life.This review explores various nano-based strategies that use nanoparticles(NPs)to lessen the harmful effects that heavy metals have on plants.Incorporated literature including published research and review papers from the year 2015 to 2023.This review paper gives a thorough review of the current situation regarding heavy metal contamination in agricultural soils and how it affects plant health.The necessity offinding practical and eco-friendly ways to address these issues is emphasized,paving the way for the introduction of NPs.Then,it highlighted the mechanistic route of heavy metal toxicity alleviation in plants by their application as well as their long-term efficiency and prospects.This review also elaborated on var-ious synthesis methods(physical,chemical,and green),but the emphasis on the green synthesis of NPs by utiliz-ing plant extract offers dependable and sustainable benefits over traditional physicochemical techniques.Under trace element stress,NPs application enhances plant antioxidant defense system,ameliorating structural changes,immobilizing trace elements in growth media,and improving the physio-chemical properties of soil as well.How-ever,there are still numerous limitations present on how these materials are synthesized,applied,and appropri-ately absorbed by plant cells.It is recommended to promote and fund long-term research to assess the long-term effects of using NPs on plant development,soil health,and possible environmental repercussions. 展开更多
关键词 NANOTECHNOLOGY heavy metals toxicity agriculture physio-chemical attributes crop yield
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Semantic Segmentation of the Intertidal Zone of an Estuary—In Search of the Best Solution
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作者 Maria da Conceição Proença Ricardo Nogueira Mendes Ricardo Melo 《Journal of Geoscience and Environment Protection》 2024年第7期1-13,共13页
An aerial photographic coverage acquired on two consecutive days in October 2021 with a ground resolution of 20 cm and a spectral resolution of 4 bands (red, green, blue and near infrared), allowed to distinguish most... An aerial photographic coverage acquired on two consecutive days in October 2021 with a ground resolution of 20 cm and a spectral resolution of 4 bands (red, green, blue and near infrared), allowed to distinguish most of the classes of interest present in the intertidal zone of the Sado estuary. We explored the possibilities of thematic classification in the powerful and complex software ArcGIS Pro;we presented the methodology used in a detailed way that allows others with minimal knowledge of GIS to reproduce the classification process without having to decipher the specifics of the software. The classification implemented used ground truth from four classes related to the macro-occupations of the area. In a first phase we explore the standard algorithms with object-based capabilities, like K-Nearest Neighbor, Random Trees Forest and Support Vector Machine, and in a second phase we proceed to test three deep learning classifiers that provide semantic segmentation: a U-Net configuration, a Pyramid Scene Parsing Network and DeepLabV3. The resulting classifications were quantitatively evaluated with a set of 500 control points in a test area of 37,500 × 12,500 pixels, using confusion matrices and resorting to Cohen’s kappa statistic and the concept of global accuracy, achieving a Kappa in the range [0.72, 0.81] and a global accuracy between 88.9% and 92.9%;the option U-Net had the most interesting results. This work establishes a methodology to provide a baseline for assessing future changes in the distribution of Sado estuarine habitats, which can be replicated in other wetland ecosystems for conservation and management purposes. 展开更多
关键词 ESTUARY Intertidal Zone ArcGIS Pro SEGMENTATION Global Changes
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