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Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

Journal of Geographical Sciences 2025年第1期35卷 88-111页

作者： YANG Peng SUN Kaiya ZHU Yanchao XIA Jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences department of Geography National University of Singapore State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年

作者： Yan YE Lei ZHANG Can CHEN Shan CHANG Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of Technology Second Geological Brigade of Hubei Geological Bureau College of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. Yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in South China, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, South China show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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Elemental geochemical records of seafloor hydrothermal activities in the sediments from the Okinawa Trough

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Acta Oceanologica Sinica 2007年第4期26卷 53-62页

作者： ZHAI Shikui YU Zenghui DU Tongjun department of marine geosciences Ocean University of China Qingdao 266003 China

The major and minor element contents in the sediment core H9 from the hydrothermal fields of the Okinawa Trough show a sharp change at the depth of 80 cm. The elements enriched in the upper 80 cm core are those enriched in the hydrothermal deposits and in the surface sediments recovered from the hydrothermal fields in the trough, which indicates the input of hydrothermal materials. Comparing with other hydrothermal sediments from Mid-ocean Ridges or the Lau Basin, the degree of the enrichment of elements iron, copper,cobah, and nickel is relatively low. However, the enrichment of elements manganese, lead, arsenic, antimony and mercury is remarkable. The average contents of these elements in the upper 80 cm core sediments are three to six times those in the lower section, and 3 - 12 times those in the surface sediments which are not influenced by hydrothermal activities. Hydrothermal activities have contributed significant manganese, lead, arsenic, antimony and mercury to the sediments, and these elements are distinct indicators for the hydrothermal activity in the Okinawa Trough. The significant enrichment of these elements in Core H9 upward from the depth 80 cm indicates the start or the significant enhancing of the hydrothermal activity in this area at about 5 740 aB. P. The average accumulation rate of manganese during this period is about 40 461μg/（ cm^2·ka） , which is similar to the hydrothermal sediments in the Lau Basin or the East Pacific Rise.

关键词： Okinawa Trough hydrothermal activity elemental geochemical record

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Crack mystery of the damaging Kumamoto earthquakes

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Science Bulletin 2016年第11期61卷 868-870页

作者： Dapeng Zhao Xin Liu department of Geophysics Tohoku University College of marine geosciences Ocean University of China

The 2016 Kumamoto earthquake(M 7.3 in the Japan Meteorological Agency(JMA)scale)sequence wrote a new chapter of active seismotectonics and subduction dynamics in the Japan *** earthquake sequence,

关键词：地震序列破坏性日本气象厅裂缝活动构造 Moto 动力学上地壳

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Impact and Solutions of Seawater Heterogeneity on Wide-Angle Tomographic Inversion of Crustal Velocities in Deep marine Environments—Numerical Studies

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Journal of Earth Science 2018年第6期29卷 1380-1389页

作者： Zhihui Zou Hua-Wei Zhou Harold Gurrola Aifei Bian Zhonglai Huang Jianzhong Zhang College of marine geosciences Key Lab of Submarine Geosciences and Prospecting Techniques MOEOcean University of China Evaluation and Detection Technology Laboratory of marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology department of Earth & Atmospheric Sciences University of Houston department of geosciences Texas Tech University Institute of Geophysics and Geomatics China University of Geosciences

The seawater column is typically taken as a homogeneous velocity layer in wide-angle crustal seismic surveys in marine environments. However, heterogeneities in salinity and temperature throughout the seawater layer result insignificant lateral variations in its seismic velocity, especially in deep marine environments. Failure to compensate for these velocity inhomogeneities will introduce significant artifacts in constructing crustal velocity models using seismic tomography. In this study, we conduct numerical experiments to investigate the impact of heterogeneous seismic velocities in seawater on tomographic inversion for crustal velocity models. Experiments that include lateral variation in seawater velocity demonstrated that the modeled crustal velocities were contaminated by artifacts from tomographic inversions when assuming a homogeneous water layer. To suppress such artifacts, we propose two strategies：（1） simultaneous inversion of water velocities and the crustal velocities;（2） layer-stripping inversion during which to first invert for seawater velocity and then correct the travel times before inverting for crustal velocities. The layer-stripping inversion significantly improves the modeling of variation in seawater velocity when preformed with seismic sensors deployed on the ocean bottom and in the water column. Such strategies improve crustal modeling via wide-angle seismic surveys in deep-marine environment.

关键词： deep water seismic tomography wide-angle seismic survey water heterogeneity OBS vertical cable

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Evaluation of Multi-Scale Full Waveform Inversion with marine Vertical Cable Data

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Journal of Earth Science 2015年第4期26卷 481-486页

作者： Aifei Bian Zhihui Zou Hua-Wei Zhou Jin Zhang Institute of Geophysics and Geomatics China University of Geosciences department of Earth & Atmospheric Sciences University of Houston College of marine geosciences Ocean University of China

Seismic illumination plays an important role in subsurface imaging. A better image can be expected either through optimizing acquisition geometry or introducing more advanced seismic mi- gration and/or tomographic inversion methods involving illumination compensation. Vertical cable survey is a potential replacement of traditional marine seismic survey for its flexibility and data quality. Conventional vertical cable data processing requires separation of primaries and multiples before migration. We proposed to use multi-scale full waveform inversion （FWI） to improve illumination coverage of vertical cable survey. A deep water velocity model is built to test the capability of multi-scale FWI in detecting low velocity anomalies below seabed. Synthetic results show that multi-scale FWI is an effective model building tool in deep-water exploration. Geometry optimization through target ori- ented illumination analysis and multi-scale FWI may help to mitigate the risks of vertical cable survey. The combination of multi-scale FWI, low-frequency data and multi-vertical-cable acquisition system may provide both high resolution and high fidelity subsurface models.

关键词： full waveform inversion vertical cable illumination multi-scale geometry optimization,low-frequency data velocity model.

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An Evaluation of Reverse-Time Imaging of Clustering Earthquakes

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Journal of Earth Science 2015年第4期26卷 548-555页

作者： Zhihui Zou Hua-Wei Zhou Aifei Bian Jianzhong Zhang Lei Xing College of marine geosciences Ocean University of China department of Earth & Atmospheric Sciences University of Houston Institute of Geophysics and Geomatics China University of Geosciences

Clustering earthquakes refer to the seismic events that occur closely with each other in time and space. Because their overlapping waveform records make it difficult to pick the first arrivals, the hypocenters of clustering earthquakes cannot be determined accurately by traveltime location methods. Here we apply a reverse-time imaging （RTI） method to map clustering earthquakes. Taking the advantage of directly using waveforms, the RTI method is capable to map either a single small earthquake or some densely distributed clustering earthquakes beneath a 2-D seismic array. In 3-D case the RTI method is successfully applied to locate the long-offset doublet earthquakes using the data from a set of sparsely distributed surface stations. However, for the same acquisition geometry, the RTI encounters challenges in mapping densely distributed clustering earthquakes. While it is obvious that improving the mapping of clustering earthquakes requires a denser receiver network with wider range of illumination angles, it is necessary to verify the actual resolution of the RTI method with synthetic data. In our study area in the Three Gorges region, our tests in 3-D case suggest that some events beneath the linear aligned sub-arrays have reasonable resolution.

关键词： clustering earthquakes reverse-time imaging hypocentral location microseismie the Three Gorges.

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Least-Squares Seismic Inversion with Stochastic Conjugate Gradient Method

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Journal of Earth Science 2015年第4期26卷 463-470页

作者： Wei Huang Hua-Wei Zhou department of Earth & Atmospheric Sciences University of Houston College of marine geosciences Ocean University of China

With the development of computational power, there has been an increased focus on data-fitting related seismic inversion techniques for high fidelity seismic velocity model and image, such as full-waveform inversion and least squares migration. However, though more advanced than conventional methods, these data fitting methods can be very expensive in terms of computational cost. Recently, various techniques to optimize these data-fitting seismic inversion problems have been implemented to cater for the industrial need for much improved efficiency. In this study, we propose a general stochastic conjugate gradient method for these data-fitting related inverse problems. We first prescribe the basic theory of our method and then give synthetic examples. Our numerical experiments illustrate the potential of this method for large-size seismic inversion application.

关键词： least-squares seismic inversion stochastic conjugate gradient method data fitting,Kirchhoff migration.

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West Pacific and North Indian Ocean Seafloor and Their Ocean-Continent Connection Zones: Evolution and Debates

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2283-2301页

作者： ZHANG Guowei LI Sanzhong GUO Anlin SUO Yanhui State Key Laboratory of Continental Dynamics/department of Geology Northwest University Key Lab of Submarine geosciences and Prospecting Techniques MOE College of Marine GeosciencesOcean University of China Laboratory for marine Geology Qingdao National Laboratory for Marine Science and Technology

The Indian Ocean and the West Pacific Ocean and their ocean-continent connection zones are the core area of ＂the Belt and Road＂. Scientific and in-depth recognition to the natural environment, disaster distribution, resources, energy potential of ＂the Belt and Road＂ development, is the cut-in point of the current Earth science community to serve urgent national needs. This paper mainly discusses the following key tectonic problems in the West Pacific and North Indian oceans and their ocean-continent connection zones （OCCZs）： 1. modern marine geodynamic problems related to the two oceans. Based on the research and development needs to the two oceans and the ocean-continent transition zones, this item includes the following questions. （1） Plate origin, growth, death and evolution in the two oceans, for example, 1） The initial origin and process of the triangle Pacific Plate including causes and difference of the Galapagos and West Shatsky microplates; 2） spatial and temporal process, present status and trends of the plates within the Paleo- or Present-day Pacific Ocean to the evolution of the East Asian Continental Domain; 3） origin and evolution of the Indian Ocean and assembly and dispersal of supercontinents. （2） Latest research progress and problems of mid-oceanic ridges： 1） the ridge-hot spot interaction and ridge accretion, how to think about the relationship between vertical accretion behavior of thousands years or tens of thousands years and lateral spreading of millions years at 0 Ma mid- oceanic ridges; 2） the difference of formation mechanisms between the back-arc basin extension and the normal mid-oceanic ridge spreading; 3） the differentials between ultra-slow Indian Ocean and the rapid Pacific spreading, whether there are active and passive spreading, and a push force in the mid-oceanic ridge; 4） mid-oceanic ridge jumping and termination： causes of the intra-oceanic plate reorganization, termination, and spatial jumps; 5） interaction of mantle plume and

关键词： the Belt and Road Indian Ocean West Pacific Ocean ocean-continent connection zone,seafloor marine geodynamics

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A geomorphological response of beaches to Typhoon Meari in the eastern Shandong Peninsula in China

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Acta Oceanologica Sinica 2015年第9期34卷 126-135页

作者： DING Dong YANG Jichao LI Guangxue DADA Olusegun A GONG Lixin WANG Nan WANG Xiangdong ZHANG Bin College of marine geosciences Ocean University of China National Deep Sea Center State Oceanic Administration department of marine Science and Technology Federal University of Technology

Eight representative beach profiles on the eastern coast of the Shandong Peninsula are observed and measured in 2011 and 2012 to determine the coastal processes under the lower tropical wind speed condition and the beach response to and recovery from the tropical storm Meari in a rare typhoon region. The results show that it is the enhancement and directional change of cross-shore and longshore sediment transports caused by Meari that leads to the beach morphological changes, and most of the sediment transports occur during the pre-Meari landing phase. The erosional scarp formation and the berm or beach face erosion are the main geomorphological responses of the beaches to the storm. The storm characteristics are more important than the beach shapes in the storm response process of the beaches on Shandong Peninsula. The typhoon is a fortuitous strong dynamic event, and the effect on the dissipative beach is more obvious than it is on the reflective beach in the study region. Furthermore, the beach trend is the main factor that controlls the storm effect intensity, and it is also closely related to the recovery of the beach profiles.

关键词： beach typhoon geomorphological response Shandong Peninsula in China

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