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Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science China(Technological Sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN XiaoLing 1,2.3,YU ZhiFeng 1,XIAO JingJing 1,QIU Feng 1 & ZHAO Xi 1 1 State key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China 2.0} laboratory of poyang lake wetland and watershed research,Ministry of Education,Jiangxi Normal University,Nanchang 33002.,China 3 The key laboratory of poyang lake Environment and Resource Utilization,Ministry of Education,Nanchang University,Nanchang 330031,China 1. State key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. key laboratory of poyang lake wetland and watershed research Ministry of Education Jiangxi Normal University Nanchang 330022 China 3. The key laboratory of {2. lake Environment and Resource Utilization Ministry of Education Nanchang University Nanchang 330031 China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote sensing study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

Water temperature governs organophosphate ester dynamics in the aquatic food chain of poyang lake

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Environmental Science and Ecotechnology 2024年第5期21卷 197-207页

作者： Zhenfei Yan Chenglian Feng Yiping Xu Jindong Wang Nannan Huang Xiaowei Jin Fengchang Wu Yingchen Bai State key laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China College of Environment Hohai UniversityNanjing210098China key laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China China National Environmental Monitoring Centre Beijing100012China

Organophosphate esters(OPEs)are increasingly recognized as pervasive environmental contaminants,primarily from their extensive application in flame retardants and *** their widespread presence,the intricacies of OPE bioaccumulation within aquatic ecosystems remain poorly understood,particularly the environmental determinants influencing their distribution and the bioaccumulation dynamics across aquatic food *** we show that water temperature plays a crucial role in modulating the dispersion of OPE in the aquatic environment of poyang *** quantified OPE concentrations across various matrices,uncovering levels ranging from 0.198 to 912.62. ng L^(-1) in water,0.013e493.36 ng per g dry weight(dw)in sediment,0.02.e41.92.ng per g wet weight(ww)in plankton,0.13e2.00.72.ng per g dw in benthic invertebrates,and 0.31e3956.49 ng per g dw in wild fish,highlighting a pronounced bioaccumulation ***,the intestines emerged as the principal site for OPE absorption,displaying the highest concentrations among the seven tissues *** the various OPEs,tris(chloroethyl)phosphate was distinguished by its significant bioaccumulation potential within the aquatic food web,suggesting a need for heightened *** propensity for OPE accumulation was markedly higher in benthic invertebrates than wild fish,indicating a differential vulnerability within aquatic *** study lays a foundational basis for the risk assessment of OPEs as emerging contaminants and underscores the imperative to prioritize the examination of bioaccumulation effects,particularly in benthic invertebrates,to inform future environmental safeguarding strategies.

关键词： Organophosphate esters Driving factor Bioaccumulation and biomagnification Ecological risk

Spatial and Temporal Change of Habitat Quality of poyang lake Basin in China at Small {2. Scale and Its Multidimensional Response to Landscape Pattern

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Chinese Geographical Science 2023年第3期33卷 565-582页

作者： BI Manyu ZHONG Yexi XIAO Zeping FENG Xinghua MA Hongzhi School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China key laboratory of {2. lake wetland and watershed research Ministry of Education(Jiangxi Normal University) Nanchang 330022China

The health and function of ecosystems are largely determined by the quality of habitat,and the optimal regulation of landscape patterns has become an important way to improve regional habitat *** article takes the poyang lake Basin of China as a case,reveals the spatial and temporal change of its habitat quality at the small {2. scale,and attempts to examine the multidimensional response of habitat quality to landscape pattern changes with respect to landscape compositions and landscape *** results show:1)from 2.00 to 2.2.,the overall landscape fragmentation of the basin decreased,the landscape aggregation in the central small {2.s changed significantly,and the spatial distribution of landscape elements in the central and southern small {2.s were relatively homogeneous.2.The overall habitat quality of the poyang lake Basin is at a middle to high level,with significant spatial differentiation,showing the distribution characteristics of‘high in the periphery,low in the center,high in the south and low in the north’.3)Both landscape compositions and landscape configurations influenced habitat quality,but there were obvious differences in the response *** the landscape composition and configuration dimension,the influence of landscape composition on habitat quality was greater than that of landscape configuration;from the multilevel landscape configuration dimension,compared to landscape level,landscape configuration at the class level impacted habitat quality more *** the end,this article proposes a differentiated regulation strategy for habitat quality conservation in small {2.s from the perspective of landscape patterns to improve the ecological service level of poyang lake Basin.

关键词： landscape watershed Spatial

key processes of carbon cycle and sink enhancement paths in natural wetland ecosystems in China

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Science China Earth Sciences 2024年第8期67卷 2444-2459页

作者： Jinshuai LI Tianxiang HAO Meng YANG Guirui YU key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration ***,the key carbon cycle processes in wetland ecosystems still lack a systematic *** the context of wetland protection and restoration,there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland *** this paper,the key processes of carbon cycle,such as photosynthetic carbon uptake,microbial carbon decomposition and carbon deposition and burial,are sorted out and summarized in four major wetland types,namely,swamp and peat wetlands,river and riparian wetlands,lake and lakeshore wetlands,and estuarine and coastal *** on the key processes of carbon cycle,three technological pathways for carbon sink multiplication are proposed,including,vegetation carbon sequestration and sink enhancement technology,soil carbon emission reduction technology and carbon deposition and burial *** key technologies under each pathway are further *** the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively ***,wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in *** will provide a scientific basis for the strategy of doubling the carbon sinks of China′s wetland ecosystems.

关键词： wetlands Carbon cycle Carbon sinks Technology pathways Conservation and restoration

Sensitivity of Near Real-time MODIS Gross Primary Productivity in Terrestrial Forests Based on Eddy Covariance Measurements

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Chinese Geographical Science 2015年第5期25卷 537-548页

作者： TANG Xuguang LI Hengpeng LIU Guihua LI Xinyan YAO Li XIE Jing CHANG Shouzhi key laboratory of {2. Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of Sciences key laboratory of {2. lake wetland and watershed research (Jiangxi Normal University) Ministry of Education Department of Geography University of Zurich Jilin University College of Geo Exploration Science and Technology

As an important product of Moderate Resolution Imaging Spectroradiometer(MODIS), MOD17A2.provides dramatic improvements in our ability to accurately and continuously monitor global terrestrial primary production, which is also significant in effort to advance scientific research and eco-environmental management. Over the past decades, forests have moderated climate change by sequestrating about one-quarter of the carbon emitted by human activities through fossil fuels burning and land use/land cover change. Thus, the carbon uptake by forests reduces the rate at which carbon accumulates in the atmosphere. However, the sensitivity of near real-time MODIS gross primary productivity(GPP) product is directly constrained by uncertainties in the modeling process, especially in complicated forest ecosystems. Although there have been plenty of studies to verify MODIS GPP with ground-based measurements using the eddy covariance(EC) technique, few have comprehensively validated the performance of MODIS estimates(Collection 5) across diverse forest types. Therefore, the present study examined the degree of correspondence between MODIS-derived GPP and EC-measured GPP at seasonal and interannual time scales for the main forest ecosystems, including evergreen broadleaf forest(EBF), evergreen needleleaf forest(ENF), deciduous broadleaf forest(DBF), and mixed forest(MF) relying on 16 flux towers with a total of 68 site-year datasets. Overall, site-specific evaluation of multi-year mean annual GPP estimates indicates that the current MOD17A2.product works highly effectively for MF and DBF, moderately effectively for ENF, and ineffectively for EBF. Except for tropical forest, MODIS estimates could capture the broad trends of GPP at 8-day time scale for all other sites surveyed. On the annual time scale, the best performance was observed in MF, followed by ENF, DBF, and EBF. Trend analyses also revealed the poor performance of MODIS GPP product in EBF and DBF. Thus, improvements in the

关键词： MOD 17A2 FLUXNET community eddy covariance (EC) gross primary productivity (GPP) forest ecosystem evaluation

Different provenance of separate loess sites in Yangtze River Basin and its paleoenvironmental implications

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Journal of Mountain Science 2019年第7期16卷 1616-1628页

作者： ZHANG Zhi JIA Yu-lian School of Geography and Environment Key Laboratory of Poyang Lake Wetland and Watershed ResearchMinistiy of EducationJiangxi Normal UniversityNanchang 330022China College of Chemisty and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

The dust deposits in the Yangtze River Basin(YRB)have been widely distributed along the Yangtze River *** studies mainly concentrated in its provenance of each loess site,however,the differences in provenance of loess among different sites in this area have rarely been ***,the geochemical characteristics of the2.μm fraction in the loess in separate Jiujiang,Xuancheng and Nanjing sites were *** result shows that the loess in Jiujiang and Nanjing sites,near Yangtze River riverway,share similar geochemical characteristics that may commonly derived from the detrital materials of Yangtze ***,both sites have significantly different elemental compositions compared with Xuancheng site,which is^60 km away from the Yangtze River *** sites share different geochemical characteristics with Eastern Qinling Mountains and Xifeng section on the Chinese Loess Plateau,North *** the distribution of the aeolian sand hills and the loess in this area published by previous studies,we suggest that the exposed river valley floodplain caused by weak summer monsoon provided abundant materials to form local dust cells controlled by strong winter monsoon during the glacial ***,those local loess deposits should be identified as the“valley-sourced loess”.These reveal the inherent connection between the monsoon system and the loess deposits in Yangtze River Basin.

关键词： Yangtze River Basin Geochemistry Loess provenance Valley-sourced loess Loess Plateau

Analysis of chaotic climatic process in the Tarim River Basin (I)

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research in Cold and Arid Regions 2019年第5期11卷 340-349页

作者： ZuHan Liu key laboratory of the Education Ministry for {2. lake wetland and watershed research Jiangxi Normal University Jiangxi Province key laboratory for Water Information Cooperative Sensing and Intelligent Processing Nanchang Institute of Technology

Based on observational data obtained from 1961 to 2.11 in the Tarim River Basin,China,we investigated the chaotic dynamics of temperature,precipitation,relative humidity,and *** main findings are as follow:(1)The four data series have significant chaotic and fractal behaviors,which are the result of the evolution of a nonlinear chaotic dynamic *** climatic process in the Tarim River Basin also has deterministic and stochastic characteristics.(2.To describe the temperature,precipitation,relative humidity,and evaporation dynamics,at least three independent variables at daily scale are required;in terms of complexity,their order is evaporation>temperature>precipitation>relative humidity.(3)Their respective largest Lyapunov exponentλ1 shows the order of their degree of complexity is relative humidity>temperature>precipitation≈evaporation;the maximum time scales for which the four systems can be predicted are 17 days,17 days,16 days,and 16 days,if calculated separately.(4)The Kolmogorov entropy K illustrates that the complexity of the nonlinear precipitation system is much greater than that of the other three *** temperature and evaporation systems exhibit weaker chaotic behavior,their predictability is better,and the degree of complexity is less than that of the other two factors.

关键词： chaos climatic process largest Lyapunov exponent Kolmogorov entropy correlation dimension

Colonization–competition dynamics of basal species shape food web complexity in island metacommunities

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Marine Life Science & Technology 2023年第2期5卷 169-177页

作者： Guanming Guo Fei Zhao Ivan Nijs Jinbao Liao Ministry of Education’s key laboratory of {2. lake wetland and watershed research School of Geography and EnvironmentJiangxi Normal UniversityNanchang 330022China research Group in Plants and Ecosystems Department of BiologyUniversity of Antwerp2610 WilrijkBelgium

Exploring how food web complexity emerges and evolves in island ecosystems remains a major challenge in *** webs assembled from multiple islands are commonly recognized as highly complex trophic networks that are dynamic in both space and *** the context of global climate change,it remains unclear whether food web complexity will decrease in a monotonic fashion when undergoing habitat destruction(e.g.,the inundation of islands due to sea-level rise).Here,we develop a simple yet comprehensive patch-dynamic framework for complex food web metacommunities subject to the competition-colonization tradeof between basal *** found that oscillations in food web topological complexity(characterized by species diversity,mean food chain length and the degree of omnivory)emerge along the habitat destruction *** outcome is robust to changing parameters or relaxing the assumption of a strict competitive *** oscillations in food web complexity indicates that small habitat changes could have disproportionate negative efects on species diversity,thus the success of conservation actions should be evaluated not only on changes in biodiversity,but also on system robustness to habitat ***,this study provides a parsimonious mechanistic explanation for the emergence of food web complexity in island ecosystems,further enriching our understanding of metacommunity assembly.

关键词： Competition-colonization tradeof Food web complexity Hierarchical competition Patch-dynamic framework Patch loss

Spatial heterogeneity of dead fuel moisture content in a Larix gmelinii forest in Inner Mongolia using geostatistics

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Journal of Forestry research 2021年第2期32卷 569-577页

作者： Heng Zhang Shihao Ma Ping Kang Qiuliang Zhang Zhiwei Wu Forestry College of Inner Mongolia Agricultural UniversityHohhot 010019People’s Republic of China key laboratory of {2. lake wetland and watershed research Ministry of EducationJiangxi Normal UniversityNanchang 330022People’s Republic of China

Spatial heterogeneity of fuel moisture content determines the spread rate and direction of a forest *** on the spatial heterogeneity of the moisture content of dead fuel of Larix gmelinii *** that:(1)fuel moisture content in litter layer2.the sill value of the semi-humus layer was highest,the humus layer moderate,the litter layer the smallest,overall,the spatial heterogeneity of the semi-humus layer was the *** humus layer in the slant direction and three layers in a vertical direction showed strong spatial correlation with the lowest nugget coefficient of 0.0968;(3)the fuel moisture content of the humus layer showed strong spatial anisotropy;and,(4)estimating the total moisture content of the sampling site by stimulated sampling reasonable control of the sampling interval,and increasing the sampling intensity can reduce the *** the sampling intensity is increased to more than 16 and the sampling interval 3 m,the standard error is<15%.The spatial heterogeneity of fuel moisture content is best revealed by increasing sampling density,sampling in different fire seasons,and in different slope directions and *** results can provide a scientific basis for forest fire prediction and prevention.

关键词： Forest combustibles Spatial heterogeneity Analog sampling Standard error