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Panoptic UAV:Panoptic Segmentation of UAV Images for Marine Environment Monitoring
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作者 Yuling Dou Fengqin Yao +7 位作者 Xiandong Wang Liang Qu Long Chen Zhiwei Xu Laihui Ding Leon Bevan Bullock Guoqiang Zhong Shengke Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期1001-1014,共14页
UAV marine monitoring plays an essential role in marine environmental protection because of its flexibility and convenience,low cost and convenient maintenance.In marine environmental monitoring,the similarity between... UAV marine monitoring plays an essential role in marine environmental protection because of its flexibility and convenience,low cost and convenient maintenance.In marine environmental monitoring,the similarity between objects such as oil spill and sea surface,Spartina alterniflora and algae is high,and the effect of the general segmentation algorithm is poor,which brings new challenges to the segmentation of UAV marine images.Panoramic segmentation can do object detection and semantic segmentation at the same time,which can well solve the polymorphism problem of objects in UAV ocean images.Currently,there are few studies on UAV marine image recognition with panoptic segmentation.In addition,there are no publicly available panoptic segmentation datasets for UAV images.In this work,we collect and annotate UAV images to form a panoptic segmentation UAV dataset named UAV-OUC-SEG and propose a panoptic segmentation method named PanopticUAV.First,to deal with the large intraclass variability in scale,deformable convolution and CBAM attention mechanism are employed in the backbone to obtain more accurate features.Second,due to the complexity and diversity of marine images,boundary masks by the Laplacian operator equation from the ground truth are merged into feature maps to improve boundary segmentation precision.Experiments demonstrate the advantages of PanopticUAV beyond the most other advanced approaches on the UAV-OUC-SEG dataset. 展开更多
关键词 Panoptic segmentation UAV marine monitoring attention mechanism boundary mask enhancement
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Radioactivity monitoring in environmental water and air around QNPP 被引量:4
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作者 XIANG Yuanyi WANG Kan ZHANG Yu CAO Zhonggang YE Jida WANG Hongfeng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第5期316-320,共5页
Results of environmental radioactivity monitoring around Qinshan Nuclear Power Plant (QNPP) are reported in this paper. From 1992 to 2005, concentrations of 90Sr, 137Cs and 3H in terrestrial freshwater are (4.4±1... Results of environmental radioactivity monitoring around Qinshan Nuclear Power Plant (QNPP) are reported in this paper. From 1992 to 2005, concentrations of 90Sr, 137Cs and 3H in terrestrial freshwater are (4.4±1.7) mBq·L-1, (0.3±0.1) mBq·L-1 and (1.6±0.5) Bq·L-1, respectively, and (2.8±2.4) Bq·L-1 of 3H in rainwater. Concentrations of 90Sr, 137Cs and 3H in the seawater samples collected from sea area nearby QNPP are (5.4±4.1) mBq·L-1, (0.7±0.2) mBq·L-1 and (1.0±0.5) Bq·L-1, respectively. Concentrations of 90Sr, 137Cs and 3H in the total waste water discharged from NPP-I are (4.0±1.8) m Bq·L-1, (1.0±0.5) mBq·L-1 and (2.8±2.2) Bq·L-1, respectively, and (1.4±0.4) Bq·L-1 of 3H in seawater sampled from No.1 outlet. Atomspheric 3H concentration in 1993~2005 at two monitoring sites is (78.9±96.3) and (64.2±40.2) mBq·m-3, respectively, with an increasing trend after 2003. Atmospheric 14C concentrations at the two sites are in the same levels as the background and data of the reference site. 展开更多
关键词 环境监视 放射污染 水污染 空气污染
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Study on the System of Aquatic Environmental Monitoring Methods in China 被引量:1
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作者 ZHANG Xiao-ling DENG Li SUN Jing 《Meteorological and Environmental Research》 CAS 2012年第3期53-56,共4页
The development of Chinese system of aquatic environmental monitoring methods was summarized. The existing problem of the system of aquatic environmental monitoring methods was analyzed. At last, some suggestions were... The development of Chinese system of aquatic environmental monitoring methods was summarized. The existing problem of the system of aquatic environmental monitoring methods was analyzed. At last, some suggestions were made on setting and implementing the system of aquat- ic environmental monitoring methods in China. 展开更多
关键词 Aquatic quality standards The system of aquatic environmental monitoring methods China
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Optimization of Shanghai Marine Environmental Monitoring Sites in the Identification of Boundaries of Different Water Quality Grades
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作者 FAN Haimei GAO Bingbo +4 位作者 WANG Jinfeng QIN Xiaoguang LIU Pengxia HU Maogui XU Peng 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期846-854,共9页
Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental... Water quality is critical to ensure that marine resources and the environment are utilized in a sustainable manner. The objective of this study is therefore to investigate the optimum placement of marine environmental monitoring sites to monitor water quality in Shanghai, China. To improve the mapping or estimation accuracy of the areas with different water quality grades, the monitoring sites were fixed in transition bands between areas of different grades rather than in other positions. Following bidirectional optimization method, first, 18 candidate sites were selected by filtering out specific site categories. Second, three of these were, in turn, eliminated because of the rule defined by the changes in the areas of water quality grades and by the standard deviation of the interpolation errors of dissolved inorganic nitrogen(DIN) and phosphate(PO_4-P). Furthermore, indicator kriging was employed to depict the transition bands between different water quality grades whenever new sampling sites were added. The four optimization projects of the newly added sites reveal that, all optimized sites were distributed in the transition bands of different water grades, and at the same time in the areas where the historical sites were sparsely distributed. New sites were also found in the overlap region of different transition bands. Additional sites were especially required in these regions to discriminate the boundaries of different water quality grades. Using the bidirectional optimization method of the monitoring sites, the boundaries of different water quality grades could be determined with a higher precision. As a result, the interpolation errors of DIN and PO_4-P could theoretically decrease. 展开更多
关键词 bidirectional OPTIMIZATION method boundaries of water quality GRADES CHANGJIANG River ESTUARY and its adjacent areas transition bands indicator KRIGING
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Analysis of Existing Problems and Treatment Methods of Urban Environmental Monitoring
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作者 Zhang Qiandong Song Xin 《Journal of Environmental Science and Engineering(A)》 2022年第2期49-54,共6页
With the rapid development of the city,the concept of ecological environment has been integrated into everyone’s heart.In the new era,people also have higher requirements for the quality of living environment.However... With the rapid development of the city,the concept of ecological environment has been integrated into everyone’s heart.In the new era,people also have higher requirements for the quality of living environment.However,at this stage,with the development of urbanization and industrialization,the problem of environmental pollution has become more and more serious.Therefore,we must do a good job in urban environmental monitoring,pay attention to the protection of urban environment,design and implement effective governance methods,so as to improve the quality of environmental governance.This article analyzes the problems in urban environmental monitoring,and formulates reasonable treatment methods and suggestions. 展开更多
关键词 Urban environmental monitoring PROBLEMS governance methods ANALYSIS
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Discussion on Top-level Design of the Environmental Monitoring Standard System Based on the Changes of 109 Method Standards for Surface Water
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作者 Haiqiong MAO Shuangye PAN +7 位作者 Huanyin FENG Yun XU Bijun SHEN Zhongquan CHEN Binjian YANG Kai CHEN Shayi WANG Jianxun SHI 《Meteorological and Environmental Research》 CAS 2022年第2期56-60,共5页
The changes of 109 analytical methods for surface water in the past 20 years since the implementation of Environmental Quality Standards for Surface Water(GB 3838-2002)were analyzed.Concidering with the analysis of sp... The changes of 109 analytical methods for surface water in the past 20 years since the implementation of Environmental Quality Standards for Surface Water(GB 3838-2002)were analyzed.Concidering with the analysis of specific items in the quality standard,it is suggested that the monograph method and the general method(the general method is moved to the standard collection of general rules and standards)can be combined when the analytical method is newly formulated and revised in the future;the limit table of the quality standard or pollution source emission standard is moved to the collection of general rules and standards,and the referenced analysis method standards are deleted.The description of analysis method standard is more succinct,and the structure of the whole ecological environment standard system is clearer. 展开更多
关键词 Surface water STANDARD System
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Eutrophication of Jiangsu Coastal Water and Its Role in the Formation of Green Tide
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作者 XIAO Mingyan SONG Weina +2 位作者 ZHANG Haibo SHI Xiaoyong SU Rongguo 《Journal of Ocean University of China》 CAS CSCD 2024年第1期109-118,共10页
Since 2007,the large-scale green tide caused by Ulva prolifera(U.prolifera)have occurred as a recurrent phenomenon in the southern Yellow Sea of China.Field surveys and satellite remote sensing showed that the small s... Since 2007,the large-scale green tide caused by Ulva prolifera(U.prolifera)have occurred as a recurrent phenomenon in the southern Yellow Sea of China.Field surveys and satellite remote sensing showed that the small scattered patches of green tide algae were first observed along the Porphyra agriculture area of the Subei Shoal in late April.In this study,we attempted to identify the role of eutrophication in the origin of the green tide in the Subei Shoal and its adjacent area.Subei Shoal and its adjacent area are characterized by rich nutrients,especially NO_(3)^(-)-N,NH_(4)^(+)-N,PO_(4)^(3-)-P,and other bioavailable components(such as urea-N and amino acids).In the spring of 2017,the average concentrations of NO_(3)^(-)-N were 19.01±11.01μmolL^(-1),accounting for 86.68%of the dis-solved inorganic nitrogen(DIN).In addition,the average concentration of NH4^(+)-N was 2.51±1.60μmolL^(-1).PO_(4)^(3-)-P had an average concentration of 0.14±0.13μmolL-1.The average concentrations of urea-N and total hydrolyzed amino acids(THAA)were 1.73±1.36μmolL^(-1)and 1.33±0.80μmolL^(-1),respectively.Rich nutritive substances play a key role in the rapid production of U.prolifera and make the Jiangsu coastal water an incubator for green tide. 展开更多
关键词 green tide NUTRIENTS ALGAE Ulva prolifera EUTROPHICATION Subei Shoal
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Health risk assessment of trace metal(loid)s in agricultural soils based on Monte Carlo simulation coupled with positive matrix factorization model in Chongqing, southwest China
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作者 MA Jie CHU Lijuan +3 位作者 SUN Jing WANG Shenglan GE Miao DENG Li 《Journal of Mountain Science》 SCIE CSCD 2024年第1期100-112,共13页
This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed ... This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)<total carcinogenic risk ≤ 10^(-4)), with higher risks observed for children compared to adults. The relationship between TMs, their sources, and health risks indicated that urban and industrial sources were primarily associated with As, contributing to 75.1% of carcinogenic risks and 55.7% of non-carcinogenic risks, making them the primary control factors. Meanwhile, agricultural sources were primarily linked to Cd and Pb, contributing to 13.1% of carcinogenic risks and 21.8% of non-carcinogenic risks, designating them as secondary control factors. 展开更多
关键词 Monte Carlo simulation Health risk assessment Trace metal(loid)s Positive matrix factorization Agricultural soils
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Simulating the evolution of focused waves by a two-layer Boussinesq-type model
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作者 Ping Wang Zhongbo Liu +3 位作者 Kezhao Fang Wenfeng Zou Xiangke Dong Jiawen Sun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期91-99,共9页
Accurate simulation of the evolution of freak waves by the wave phase focusing method requires accurate linear and nonlinear properties,especially in deep-water conditions.In this paper,we analyze the ability to simul... Accurate simulation of the evolution of freak waves by the wave phase focusing method requires accurate linear and nonlinear properties,especially in deep-water conditions.In this paper,we analyze the ability to simulate deep-water focused waves of a two-layer Boussinesq-type(BT)model,which has been shown to have excellent linear and nonlinear performance.To further improve the numerical accuracy and stability,the internal wavegenerated method is introduced into the two-layer Boussinesq-type model.Firstly,the sensitivity of the numerical results to the grid resolution is analyzed to verify the convergence of the model;secondly,the focused wave propagating in two opposite directions is simulated to prove the symmetry of the numerical results and the feasibility of the internal wave-generated method;thirdly,the limiting focused wave condition is simulated to compare and analyze the wave surface and the horizontal velocity of the profile at the focusing position,which is in good agreement with the measured values.Meanwhile the simulation of focused waves in very deep waters agrees well with the measured values,which further demonstrates the capability of the two-layer BT model in simulating focused waves in deep waters. 展开更多
关键词 focused waves numerical simulation Boussinesq-type model velocity profile
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Morphological,phylogenetic and metabolite profile of Prorocentrum clipeus,a newly recorded epiphytic dinoflagellate in the northern Yellow Sea
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作者 Ruifang Wang Mengmeng Tong +10 位作者 Shiwen Zhou Junjie Zheng Wenguang Zhang Xinfeng Dai Douding Lu Jiarong Hu Tianze Leng Qinglin Mu Zhongyong Yan Jiangning Zeng Pengbin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期128-141,共14页
More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of ... More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of benthic Prorocentrum species have been reported in tropical and subtropical waters of China.In contrast,only a few benthic Prorocentrum species have been reported in temperate waters.In this study,morphological descriptions obtained using light microscopy,scanning electron microscopy and molecular characterization of one Prorocentrum clipeus strain isolated from the Yellow Sea are presented.Prorocentrum clipeus cells were nearly circular in shape,with a collar,ridge,and one protrusion.The periflagellar area was wide U-shaped,with two curved projections on platelet 1a.Nine periflagellar platelets of different sizes were observed.The morphology closely fits that of the species isolated from other locations.Phylogenetic analysis based on the molecular sequences of the small subunit(SSU)rDNA,internal transcribed spacer(ITS),and large subunit(LSU)rDNA was performed.A comprehensive metabolomic analysis incorporating target,suspect and non-target screenings was first applied to investigate the intracellular and extracellular metabolite profiles of the current isolate of P.clipeus.According to the results of the target and suspect screenings,179 metabolites or toxins produced by DSP-related algal species,including OA,dinophysistoxin-1(DTX1),dinophysistoxin-2(DTX2)and pectenotoxin-2(PTX2),were not detected.Non-target screening involving feature-based molecular networking(FBMN)provided a global view of major metabolites produced by the P.clipeus DF128 strain and revealed 23 clusters belonging to at least 13 compound classes,with organometallic compounds,lipids and lipid-like molecules,phenylpropanoids and polyketides,and benzenoids as major types.To date,this is the first record of the characterization of P.clipeus in samples from Chinese waters.Our results support the wide distribution of epibenthic Prorocentrum species. 展开更多
关键词 PROROCENTRUM taxonomy PHYLOGENY metabolite profiling Yellow Sea
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Temporal and Spatial Distribution of DIN and DIP Concentrations and Source Apportionment Along the Bohai Sea of China During 2015-2022
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作者 ZHANG Xinjie TIAN Chongguo +3 位作者 SUN Zeyu YIN Xuehua SUN Rong WANG Juying 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1004-1016,共13页
The Bohai Sea is one of the most polluted sea areas in China.In this study,we used 2184 integrated concentrations of dis-solved inorganic nitrogen(DIN)and dissolved inorganic phosphorus(DIP)in the Bohai Sea of China d... The Bohai Sea is one of the most polluted sea areas in China.In this study,we used 2184 integrated concentrations of dis-solved inorganic nitrogen(DIN)and dissolved inorganic phosphorus(DIP)in the Bohai Sea of China during spring(March,April,and May),summer(June,July,and August),and autumn(October and November)from 2015 to 2022 to explore the trends and sources of nutrients variations.From 2015 to 2022,DIN showed a downward trend until 2020 and then an upward trend,whereas DIP exhibited a stable trend with a slight decrease.The concentrations of DIN and DIP had similar seasonal pattern which was the highest in autumn(0.292±0.247 mg/L for DIN and 0.013±0.016 mg/L for DIP)but lower in spring(0.267±0.238 mg/L for DIN and 0.006±0.010 mg/L for DIP)and summer(0.263±0.324 mg/L for DIN and 0.008±0.010 mg/L for DIP).Sources of DIN and DIP apportioned by the positive matrix factorization(PMF)model were riverine input,sediment resuspension,sewage discharge,atmospheric deposition,and underground input.During 2015-2022,the largest contributor to DIN was sewage discharge(28.7%)and the largest contributor to DIP was sediment resuspension(44.6%).Seasonally,DIN in spring and autumn was dominated by sewage discharge(45.4%and 27.8%,re-spectively).Whereas in summer,it was dominated by riverine input(32.4%)and atmospheric deposition(29.7%).DIP was dominated by sediment resuspension during all three seasons(35.8%-52.5%).In addition,the increase in DIN concentrations in 2021 and 2022 were mainly due to the incremental input of river discharge and atmospheric deposition caused by increased precipitation during sum-mer and autumn. 展开更多
关键词 dissolved inorganic nitrogen(DIN) dissolved inorganic phosphorus(DIP) source apportionment positive matrix factoriza-tion(PMF)model the Bohai Sea of China
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Dietary exposure to sulfamethazine,nanoplastics and their binary mixture disrupts the spermatogenesis of marine medaka(Oryzias melastigma)
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作者 Yuting Zhang Ruanni Chen +6 位作者 Zhiqiang Chen Xiaoyu Fu Ziyi Wu Jinwan Chen Lingtian Xie Humin Zong Jingli Mu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期104-110,共7页
In the coastal environment,the co-occurrence of antibiotic and nanoplastic pollution is common.Investigating their individual and combined toxicity to marine organisms is of great necessity.In the present study,the re... In the coastal environment,the co-occurrence of antibiotic and nanoplastic pollution is common.Investigating their individual and combined toxicity to marine organisms is of great necessity.In the present study,the reproductive toxicity of sulfamethazine(SMZ)and nanoplastics(polystyrene,PS)via the dietary route on the spermatogenesis of marine medaka(Oryzias melastigma)was examined.After 30 d of dietary exposure,SMZ alone decreased the gonadosomatic index(GSI)value(~35%)and the proportion of undifferentiated type A spermatogonia(A_(und))(~40%),probably by disrupting the testicular sex hormone production,the spermatogenesis-related growth factor network and the balance of apoptosis.Individual exposure to PS did not affect the GSI value or the proportions of germ cells at different developmental stages,but dysregulated the expression of several spermatogenesis-related genes.Interestingly,the presence of PS alleviated the decreased GSI value caused by SMZ.This alleviation effect was achieved by enhancing the spermatogonia differentiation instead of reversing the suppressed self-renewal of A_(und),suggesting that the mixture of PS and SMZ could cause reproductive effects in a different way.These findings expand our knowledge of threats of ubiquitous antibiotic and nanoplastic pollution to fish reproduction and population. 展开更多
关键词 nanoplastics ANTIBIOTICS SPERMATOGENESIS combined toxicity Oryzias melastigma
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Spatial-temporal heterogeneity of ecological quality changes across the Qinghai-Tibet Plateau under the influence of climate factors and human activities
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作者 ZiPing Zhang YuWei Cui +1 位作者 WenJia Tang Sen Li 《Research in Cold and Arid Regions》 CSCD 2024年第3期129-140,共12页
Over the last few decades,the ecological quality of the Qinghai–Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecol... Over the last few decades,the ecological quality of the Qinghai–Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecological quality and dominant factors is crucial for sustainable development.In this study,the changes in the ecological quality on the QTP from 2000 to 2020 were evaluated based on aggregated indices and Sen–MK trend analyses,and the dominant factors affecting the ecological quality of the QTP were quantitatively analyzed using decision tree classification.The results revealed that(1)the ecological quality of the QTP exhibited an overall high trend in the east and a low pattern in the west;(2)the ecological quality of the QTP significantly increased from 2000 to 2020,and human activities were the dominant factors causing this change;and(3)the changes in the ecological quality and dominant factors exhibited obvious spatiotemporal heterogeneity.The area with an improved ecological quality occurred mainly in the northern QTP region.It was governed by human activities and precipitation.In contrast,the area with a deteriorated ecological quality occurred largely in the southern QTP region and was dominated by human activities and temperature.The 2000–2010 period was the most significant period of heterogeneity regarding of ecological quality and its driving factors.(4)The change in the ecological quality was mainly affected by the synergistic relationship between human activities and climate change in this region,which encompassed multiple dominant factors.This study provides important information on the spatiotemporal heterogeneity of ecological quality change and its dominant factors on the QTP and offers systematic guidance for the planning and implementation of ecological protection projects. 展开更多
关键词 Remote sensing-based ecological index(RSEI) Dominant factors Synergies and trade-offs Qinghai‒Tibet Plateau
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Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific
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作者 Yachang Cheng Lei Zhu +6 位作者 Lin Xue Shisheng Ma Nan Jia Shaoping Zang Zhihai Cao Jing Yuan Yang Liu 《Avian Research》 SCIE CSCD 2024年第1期27-34,共8页
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to... Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel. 展开更多
关键词 Behavioral strategy BIOLOGGING Central place foraging Marine primary productivity Seabird Sea surface temperature
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Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River
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作者 ZHANG Han BURNETT CWilliam +5 位作者 ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao 《Journal of Ocean University of China》 CAS CSCD 2024年第1期99-108,共10页
Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and ... Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(<32µm)was mainly from the erosion of soil along the lower reaches of the Yellow River,while coarse SPM(>32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea. 展开更多
关键词 the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator
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Salinity fronts shape spatial patterns in zooplankton distribution in Hangzhou Bay
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作者 Yepeng Xu Yiqi Wang +11 位作者 Lin Zhan Yijun Ou Kangning Jia Ming Mao Xuyu Zhu Zhibing Jiang Yuanli Zhu Wei Huang Ping Du Jiangning Zeng Lu Shou Feng Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期96-106,共11页
Ocean fronts play important roles in nutrient transport and in the shaping ecological patterns.Frontal zones in small bays are typically small in scale,have a complex structure,and they are spatially and temporally va... Ocean fronts play important roles in nutrient transport and in the shaping ecological patterns.Frontal zones in small bays are typically small in scale,have a complex structure,and they are spatially and temporally variable,but there are limited data on how biological communities respond to this variation.Hangzhou Bay,a mediumsized estuary in China,is an ideal place in which to study the response of plankton to small-scale ocean fronts,because three water masses(Qiantang River Diluted Water,Changjiang River Diluted Water,and the East China Sea current) converge here and form dynamic salinity fronts throughout the year.We investigate zooplankton communities,and temperature,salinity and chlorophyll a(Chl a) in Hangzhou Bay in June(wet perio d) and December(dry period) of 2022 and examine the dominant environmental factors that affect zooplankton community spatial variability.We then match the spatial distributions of zooplankton communities with those of salinity fronts.S alinity is the most important explanatory variable to affect zooplankton community spatial variability during both wet and dry periods,in that it contributes>60% of the variability in community structure.Furthermore,the spatial distributions of zooplankton match well with salinity fronts.During December,with weaker Qiantang River Diluted Water and a stronger secondary Changjiang River Plume,zooplankton communities occur in moderate salinity(MS,salinity range 15.6±2.2) and high salinity(HS,22.4±1.7) regions,and their ecological boundaries closely match the Qiantang River Diluted Water front.In June,different zooplankton communities occur in low salinity(LS,3.9±1.0),MS(11.7±3.6) and HS(21.3±1.9) regions.Although the LS region occurs abnormally in the central bay rather than its apex because of the anomalous influence of rising and falling tides during the sampling perio d,the ecological boundaries still match salinity interfaces.Low-salinity or brackish-water zooplankter taxa are relatively more abundant in LS or MS regions,and the biomass and abundance of zooplankton is higher in the MS region. 展开更多
关键词 ZOOPLANKTON spatial distribution salinity fronts Hangzhou Bay
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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River
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作者 LIU Xiao JIANG Xueyan +2 位作者 LIU Qian SUI Juanjuan ZOU Li 《Journal of Ocean University of China》 CAS CSCD 2024年第2期455-466,共12页
As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been c... As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment. 展开更多
关键词 chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties
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Health Assessment of Typical Reservoirs in Eastern Jilin: A Case Study of Niligou Reservoir
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作者 Meihua HUANG Jing WANG +3 位作者 Yinglin XIE Chunsheng WEI Xin TIAN Lunwen WANG 《Asian Agricultural Research》 2024年第1期17-21,共5页
Niligou Reservoir,a typical reservoir in the eastern region of Jilin Province,is subordinate to Niligou River,which is located in the Changbai Mountains in eastern Jilin,with abundant plant and animal resources and we... Niligou Reservoir,a typical reservoir in the eastern region of Jilin Province,is subordinate to Niligou River,which is located in the Changbai Mountains in eastern Jilin,with abundant plant and animal resources and well protected biodiversity in the basin,but there are also some related problems such as fragile ecosystem of forest wetland.This paper carried out a health assessment of Niligou River,including water quality monitoring,aquatic organism monitoring,and riparian zone investigation.According to the requirements of the Technical Guidelines for River and Lake Health Assessment,13 assessment indexes were selected to build a river and lake health assessment index system.By sorting and analyzing the monitoring and investigation data,we got a clear picture of the ecological environment status and existing problems of Niligou Res-ervoir.Based on the actual situation of Niligou River,we evaluated the hydrologic integrity,chemical integrity,morphological and structural integrity,biological integrity and sustainability of social service function,and put forward corresponding countermeasures according to the re-sults,in order to provide a technical support for the health treatment of rivers and lakes in Jilin Province. 展开更多
关键词 Eastern Jilin Niligou Reservoir Health assessment
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The largest CPIES array in the marginal sea:abundant dynamics in the northeast South China Sea
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作者 Hua Zheng Xiao-Hua Zhu +4 位作者 Min Wang Ruixiang Zhao Chuanzheng Zhang Feng Nan Fei Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期135-137,共3页
The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,t... The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,tropical cyclones,the Kuroshio intrusion,and water exchange through the Luzon Strait(LS). 展开更多
关键词 NORTHEAST MARGINAL abundant
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Spatial-temporal Variation Characteristics of Water Quality in the Lower Reaches of the Nenjiang River
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作者 Xiangzhe MENG Jing WANG +4 位作者 Yinglin XIE Fei PENG Chunsheng WEI Xin TIAN Lunwen WANG 《Meteorological and Environmental Research》 2024年第1期67-71,共5页
As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wet... As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wetland,the Xianghai Wetland,and the Danjiang Wetland in Jilin Province.The main problem in the lower reaches of the Nenjiang River is the uneven distribution of water resources in time and space,and the intensification of land salinization.Zhenlai County and Da an City in the Nenjiang River Basin have sufficient surface water resources,with surface water as the drinking water source.Baicheng City and Tongyu County have scarce surface water resources,and both use groundwater as their domestic water source.The main polluted section in the basin is the Xianghai Reservoir,and the annual water quality evaluation is Class V.However,the water quality of the Tao er River,the main stream of the Nenjiang River,is significantly better than that of the Xianghai Reservoir.In order to better study the water environmental pollution situation in the Nenjiang River basin,monitoring data from five sections of non seasonal rivers in the basin from 2012 to 2021 were selected for studying water quality.This in-depth exploration of the water pollution status and river water quality change trends in the Nenjiang River basin is of great significance for future rural development,agricultural pattern transformation,and the promotion of water ecological civilization construction. 展开更多
关键词 Lower reaches of the Nenjiang River Water quality Spatial-temporal variation
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