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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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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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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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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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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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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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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:6
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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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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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Environmental Benefits for Phase-Out HCFC-22 in the Residential Air-Conditioner Sector in China
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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
中国是 hydrochlorofluorocarbons (HCFC ) 的最大的制片人和消费者,并且 HCFC-22 的生产占超过 80% 所有 HCFC。这份报纸专注于居住空调机工业并且分析在中国加速 HCFC-22 的逐步淘汰的环境好处。根据基线的比较和 HCFC-22 的逐步淘... 中国是 hydrochlorofluorocarbons (HCFC ) 的最大的制片人和消费者,并且 HCFC-22 的生产占超过 80% 所有 HCFC。这份报纸专注于居住空调机工业并且分析在中国加速 HCFC-22 的逐步淘汰的环境好处。根据基线的比较和 HCFC-22 的逐步淘汰情形,将直接作为一种致冷的选择用 HC-290 (丙烷) 减少温室效应,并且间接地在电消费由于减小减少温室气体的排放的调查结果表演。HC-290 和 HFC-410A 的二种情形的比较致冷的选择证明 HC-290 致冷的愿望的使用比 HFC-410A 生产显著地更高的环境好处致冷。引证苍白, T. , Y。Dou, L. 王,等, 2011:为在在中国的居住空调机部门的逐步淘汰 HCFC-22 的环境好处。副词。Clim。变化物件, 2 (2 ) , doi:10.3724/SP .J.1248.2011.00086。 展开更多
关键词 HCFCS 环境效益 空调行业 中国 住宅 制冷剂 温室效应 电力消耗
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Saltmarsh vegetation and social environment influence flexible seasonal vigilance strategies for two sympatric migratory curlew species in adjacent coastal habitats
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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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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
关键词 更新世 鸟类 DA 葡萄牙 岩石层位学 旧石器时代 人工制品 环境解释
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Spatial-temporal variations and driving factors of soil organic carbon in forest ecosystems of Northeast China
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作者 Shuai Wang Bol Roland +4 位作者 Kabindra Adhikari Qianlai Zhuang Xinxin Jin Chunlan Han Fengkui Qian 《Forest Ecosystems》 SCIE CSCD 2023年第2期141-152,共12页
Forest soil carbon is a major carbon pool of terrestrial ecosystems,and accurate estimation of soil organic carbon(SOC)stocks in forest ecosystems is rather challenging.This study compared the prediction performance o... Forest soil carbon is a major carbon pool of terrestrial ecosystems,and accurate estimation of soil organic carbon(SOC)stocks in forest ecosystems is rather challenging.This study compared the prediction performance of three empirical model approaches namely,regression kriging(RK),multiple stepwise regression(MSR),random forest(RF),and boosted regression trees(BRT)to predict SOC stocks in Northeast China for 1990 and 2015.Furthermore,the spatial variation of SOC stocks and the main controlling environmental factors during the past 25 years were identified.A total of 82(in 1990)and 157(in 2015)topsoil(0–20 cm)samples with 12 environmental factors(soil property,climate,topography and biology)were selected for model construction.Randomly selected80%of the soil sample data were used to train the models and the other 20%data for model verification using mean absolute error,root mean square error,coefficient of determination and Lin's consistency correlation coefficient indices.We found BRT model as the best prediction model and it could explain 67%and 60%spatial variation of SOC stocks,in 1990,and 2015,respectively.Predicted maps of all models in both periods showed similar spatial distribution characteristics,with the lower SOC in northeast and higher SOC in southwest.Mean annual temperature and elevation were the key environmental factors influencing the spatial variation of SOC stock in both periods.SOC stocks were mainly stored under Cambosols,Gleyosols and Isohumosols,accounting for 95.6%(1990)and 95.9%(2015).Overall,SOC stocks increased by 471 Tg C during the past 25 years.Our study found that the BRT model employing common environmental factors was the most robust method for forest topsoil SOC stocks inventories.The spatial resolution of BRT model enabled us to pinpoint in which areas of Northeast China that new forest tree planting would be most effective for enhancing forest C stocks.Overall,our approach is likely to be useful in forestry management and ecological restoration at and beyond the regional scale. 展开更多
关键词 Soil organic carbon stocks Forest ecosystem Spatial-temporal variation Carbon sink Digital soil mapping
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Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection method using production and resilience score indices
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作者 Arnauld THIRY William J.DAVIES Ian C.DODD 《Frontiers of Agricultural Science and Engineering》 CSCD 2024年第1期169-185,共17页
In Asia, the rice crop sustains millions of people. However, growing demand for this crop needs to be met while simultaneously reducing its water consumption to cope with the effects of climate change. Lowland croppin... In Asia, the rice crop sustains millions of people. However, growing demand for this crop needs to be met while simultaneously reducing its water consumption to cope with the effects of climate change. Lowland cropping systems are the most common and productive but have particularly high water requirements. High-yielding rice genotypes adapted to drier environments(such as rainfed or aerobic rice ecosystems) are needed to increase the water use efficiency of cropping. Identifying these genotypes requires fast and more accurate selection methods. It is hypothesized that applying a new quantitative selection method(the score index selection method), can usefully compare rice yield responses over different years and stress intensities to select genotypes more rapidly and efficiently. Applying the score index to previously published rice yield data for 39 genotypes grown in no-stress and two stress environments, identified three genotypes(ARB 8, IR55419-04 and ARB 7) with higher and stable yield under moderate to severe stress conditions. These genotypes are postulated to be better adapted to stress environment such as upland and aerobic environments. Importantly, the score index selection method offers improved precision than the conventional breeding selection method in identifying genotypes that are well-suited to a range of stress levels within the target environment. 展开更多
关键词 Aerobic rice breeding selection drought resilience production capacity index resilience capacity index stress score index upland
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Promoting green transformation by ensuring food security while reducing the environmental footprint of food and farming with agriculture green development
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作者 William J.DAVIES Jianbo SHEN 《Frontiers of Agricultural Science and Engineering》 CSCD 2024年第1期1-4,I0005,共5页
Reconciling the challenges of producing adequate amounts of nutritious food for the increasing global population while limiting environmental damage that can result from operations of our food systems is an enormous c... Reconciling the challenges of producing adequate amounts of nutritious food for the increasing global population while limiting environmental damage that can result from operations of our food systems is an enormous challenge.In many parts of the world,agriculture is undergoing major transformations and this has been and still is particularly the case in China. 展开更多
关键词 operations AGRICULTURE TRANSFORMATION
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Coordinating environmental protection and agricultural development: a village-based case study for promoting green transformation
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作者 Kemo JIN Nico HEERINK +6 位作者 William JDAVIES Jianbo SHEN Yifeitong ZHANG Yong HOU Yaqiao ZHAO Zhengxiong ZHAO Fusuo ZHANG 《Frontiers of Agricultural Science and Engineering》 CSCD 2024年第1期100-112,共13页
Balancing ecological preservation with sustainable agricultural practices is a global issue. Erhai Lake has felt this challenge keenly. To address it, in 2022, a Science and Technology Backyards(STBs) project was laun... Balancing ecological preservation with sustainable agricultural practices is a global issue. Erhai Lake has felt this challenge keenly. To address it, in 2022, a Science and Technology Backyards(STBs) project was launched in Gusheng Village. The goal of this is to care for the environment while ensuring that farms and farmers can thrive sustainably. The uniqueness of the Erhai STB arises from its interdisciplinary integration, encompassing fields such as ecology, agronomy and social science, resulting in specifically-designed solutions for the Erhai context. While this model aligns with broader STB paradigms, its distinctive edge lies in technological innovation and robust support mechanisms for local agricultural stakeholders. This paper describes the methodology and outcomes of the STB initiative, highlighting its pivotal role in spearheading sustainable transition in Erhai. Preliminary findings underscore the potential of the STB model as an efficacious tool for harmonizing environmental conservation and agricultural practices, that are both financially and environmentally sustainable, rendering it a potential model for comparable regions in China and other counties. 展开更多
关键词 Agriculture green development Science and Technology Backyards Erhai environmental protection SMALLHOLDERS
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Achievements,challenges,and recommendations for waterbird conservation in China's coastal wetlands
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作者 Zhijun Ma Chi-Yeung Choi +6 位作者 Xiaojing Gan Jing Li Yang Liu David S.Melville Tong Mu Theunis Piersma Zhengwang Zhang 《Avian Research》 SCIE CSCD 2023年第3期305-314,共10页
China’s coastal wetlands provide breeding,migration stopover,and wintering habitats for about 230 waterbird species,which is more than a quarter of all waterbirds in the world.Large-scale and high intensity human act... China’s coastal wetlands provide breeding,migration stopover,and wintering habitats for about 230 waterbird species,which is more than a quarter of all waterbirds in the world.Large-scale and high intensity human activities have resulted in serious loss and degradation of coastal wetlands over the past half century,causing population declines in many waterbirds.Through a literature review and expert surveys,this article reviews conservation measures taken in recent decades to protect waterbirds in China’s coastal wetlands and provides recommendations for future conservation action from three aspects:policy and administration,habitat conservation and management,and multiparty participation.Over the past decades,many conservation legislation,regulations and action plans at the national level and more site-specific measures and interventions have been implemented,with notable improvement in the effectiveness in policy making and multi-stakeholder participation.Accordingly,some threats to waterbirds have been mitigated and many key sites for waterbirds have been designated as strictly protected nature reserves.However,some critical issues still remain,mostly related to habitat conservation and management,such as coastal wetland restoration,control of invasive Spartina alterniflora,control of environmental pollution,and improvement of artificial habitat quality.We highlight that protecting natural tidal wetlands and improving habitat quality are critical for the conservation of coastal waterbirds,especially those highly dependent on the intertidal wetlands.China has demonstrated strong commitment to ecological conservation and restoration for the future,in terms of both funding and policies for biodiversity and wetland ecosystems.It is important that this commitment to conserve coastal waterbirds is supported continuously by science-and evidence-based decisions and actions. 展开更多
关键词 Coastal zone East Asian-Australasian Flyway HABITAT Intertidal flat Management SHOREBIRD
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