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Sediment records of environmental changes in the south end of the Zhejiang-Fujian coastal mud area during the past 100 years

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Chinese Journal of Oceanology and Limnology 2014年第4期32卷 899-908页

作者：王琳淼李广雪高飞刘玲刘勇 DADA Olusegun A College of Marine Geoscience Ocean University of China Key Laboratory of Submarine and Prospecting Techniques Ocean University of China Department of Marine Science and Technology Federal University of Technology

Previous studies carried out in the East China Sea （ECS） mud area focused on long-term environmental changes in sedimentary records during the Holoeene, especially during the mid-Holocene high-stand water levels period. These results indicate that sensitive grain size groups can be used as a sedimentary proxy to reconstruct the evolution of the East Asian Winter Monsoon （EAWM）. The studies have been carried out mainly in the northern and middle portions of the Zhejiang-Fujian coastal mud, however, similar research in the southern portion and the comparison between sedimentary proxy and modern measured data of EAWM are lacking. In this paper, we focused on a sedimentary record of the past 100 years with an enhanced resolution of 1.8 years. Investigations of the southern end of the Zhejiang-Fujian coastal mud area were conducted on the basis of 21~Pb chronology, grain-size analysis and chemical element analysis. The correspondence between the mean grain size （Mz） of sediment sensitive grain size and the measured EAWM was confirmed for the first time. We found that during the recent 100 years, the variation of the mean grain size of the sensitive population in the southern portion of the Zhejiang-Fujian mud was mainly controlled by the EAWM intensity changes; and not directly related to changes in the sediment discharge from Datong station of the Changjiang River （DTSD）. Finally, recent changes in the content of heavy metals in study area reflect the impact of human activities on the environment.

关键词： Zhejiang-Fujian coast sedimentary record environmental changes East Asian Winter Monsoon(EAWM)

Responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain

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Avian Research 2023年第3期14卷 336-344页

作者： Guangyao Wang Jinming Zhao Weiqiang Li Xiangrong Song Yong Zhang Chunlin Li Willem F.de Boer School of Resources and environmental Engineering Anhui UniversityHefei230601China School of Life Science Huaibei Normal UniversityHuaibei235000China College of Biology and the Environment Nanjing Forestry UniversityNanjing210037China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration Anhui UniversityHefei230601China Wildlife Ecology and Conservation Group Wageningen University&Research6708PBWageningenthe Netherlands

In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative ***,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic *** the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus formulate effective management and conservation *** this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and *** predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) differed between the two years,and that these differences were correlated with the temporal changes in environmental *** the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in *** individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou *** overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic *** species composition was significantly different between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human *** most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local *** study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,

关键词： Artificial wetlands environmental changes Subsidence wetlands Waterbird community

The sources and composition of organic matter in sediments of the Jiaozhou Bay：implications for environmental changes on a centennial time scale

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Acta Oceanologica Sinica 2017年第11期36卷 68-78页

作者： KANG Xuming SONG Jinming YUAN Huamao LI Xuegang LI Ning DUAN Liqin Key Laboratory of Marine Ecology and environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Laboratory for Marine Ecology and environmental Sciences Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China University of Chinese Academy of Sciences Beijing 100049 China

The Jiaozhou Bay is characterized by heavy eutrophication that is associated with intensive anthropogenic activities. Four core sediments from the Jiaozhou Bay are analyzed using bulk technologies, including sedimentary total organic carbon（TOC）, total nitrogen（TN）, the stable carbon（δ13C） and nitrogen（δ15 N） isotopic composition to obtain the comprehensive understanding of the source and composition of sedimentary organic matter and further shed light on the environmental changes of the Jiaozhou Bay on a centennial time *** suggest that the TOC and TN concentrations increase in the upper core, having indicated a probable eutrophication process since the 1920 s in the inner bay and the 2000 s in the bay mouth. The TOC and TN concentrations outside the bay have also changed since 1916 owing to the variation of terrigenous *** TOC/TN ratio, δ13 C and δ15 N, it can be concluded there is a mixture of terrigenous and marine organic matter sources in the study area. A simple two end-member（terrigenous and marine） mixing model usingδ13 C indicats that 45%–79% of TOC in the Jiaozhou Bay is from the marine source. The environmental changes of the Jiaozhou Bay are recorded by geochemical proxies, which are influenced by the intensive anthropogenic activities（e.g., extensive use of fertilizers, and discharge of sewage） and climate changes（e.g., rainfall）.

关键词： organic matter sources anthropogenic activities environmental changes sediments Jiaozhou Bay

Soil Organic Carbon and Labile Carbon Along a Precipitation Gradient and Their Responses to Some environmental changes

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Pedosphere 2005年第5期15卷 676-680页

作者： WANG Shu-Ping ZHOU Guang-Sheng GAO Su-Hua GUO Jian-Ping Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing 100093（China） College of Resources and Environment Graduate School of the Chinese Academy of Sciences Beijing 100049 （China） Chinese Academy of Meteorological Science Beijing 100081 （China）

Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mol-1with different soil moisture contents of 30%-45%, 45%-60%, and 60%-80% soil water holding capacity, the distributionof soil organic carbon and labile carbon along the NECT, their relationships with precipitation and their responses toCO2 enrichment and soil moisture changes were analyzed. The results indicated that the soil labile carbon along thegradient was significantly related to soil organic carbon (r = 0.993, P environmental changes than soil organic carbon.

关键词： environmental changes labile carbon organic carbon precipitation gradient soil

Population growth，economic growth，technology changes in relation to environmental changes──A theoretical modelling analysis of environmental changes

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Journal of environmental Sciences 1994年第4期6卷 412-421页

作者： Hu Angang(Research Center for Eco-environmental Sciences ,Chinese Acaderny of Sciences. Beijing 100085 , China)

This paper mainly deals with the impact of three major factors , namely population growth,economic growth and technology changes, on the changes of environmental quality. It presents a curve ofenvironmental changes in relation to demographic transition and process of industrialization. It concludesthat a major way of improving environmental quality is to intensify pollution decreasing technical factorsand that control of population growth will also reduce the pressure on the environment.

关键词： Population growth economic growth environmental changes ttchnolilgy change.

environmental changes Analysis of Hongjiannao Lake During Recent Fifty Years——Based on the Data of Lake Sediments

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Agricultural Science & Technology 2009年第6期10卷 178-183页

作者：李双陈硕张家武兰州大学西部环境教育部重点实验室甘肃兰州730000

Particle size, the contents of carbonate and TOC were analyzed on lake sediments from a short core in Hongjiannao Lake to discuss the environmental changes during the past decades. On the basis of the records in lake sediments and comparison with the meteorological data of Yulin region, the environmental changes in Hongjiannao Lake were approximately divided into two stages. In stage A （1957 -1996）, the lake evolution and the environmental change were mainly influenced by natural factors. It contains three sub-stages： A1 （1957-1969）, a period of lake expansion, A2 （1969-1990）, a stable period with high lake levels, and A3 （1990 -1996）, a period of gradual extraction of the lake. In stage B （1996 -2005）, the lake area still keeps diminishing. During this period, organic matter increased rapidly due to the input of nutrient elements in the catchment. The carbonate content, however, decreased. As the precipitation was decreasing and the temperature was increasing, the decrease of carbonate content could not be explained by either temperature or precipitation change.

关键词： Hongjiannao Lake Particle size TOC Carbonate environmental changes

Mountain evolution and environmental changes of Huangshan(Yellowmountain),China

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Journal of Geographical Sciences 1999年第1期9卷 25-34页

作者： HUANG Pei-hua R.F. Diffendal,Jr. YANG Min-qing P.E. Helland(University of Science and Technology of China, Hefei 230026, China Conservation and Survey, University of Nebraska-Lincoln, Lincoln,NE 68588-0517 USA Nebraska Department of environmental Qua

Huangshan (Yellow Mountain) is located in southern part of the lower reaches of the Yangtze River. The highest Lotus Flower peak is 1864 m above sea level. Formative ages of the Huangshan and its granite,process of mountain geomorphic evolution from the Eocene to Quaternary,environmental changes of Quaternary, formative origin of beautiful peaks and fascinating rocks were studied and the questionable 'Pleistocene glaciation' was also discussed in this paper.

关键词： mountain evolution environmental changes questionable “Pleistocene glaciation” Huangshan

The International Workshop on environmental changes and Sustainable Development in Arid and Semi-arid Regions

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Journal of Geographical Sciences 2007年第4期17卷 512-512页

作者： ZHAO Xin

The International Workshop on environmental changes and Sustainable Development in Arid and Semi-arid Regions was held on September 10-14, 2007 in Alashan Left Banner, Inner Mongolia, China. A total of 81 delegates from 17 countries attended this workshop, including Australia, Egypt, Germany, Iceland, Italy, Kuwait, The Netherlands, Oman,

关键词：半干旱区环境演变可持续发展国际学术讨论会阿拉善 Sustainable Development environmental changes

Paleoenvironmental changes during the late Quaternary as inferred from foraminifera assemblages in the Laizhou Bay

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Acta Oceanologica Sinica 2014年第10期33卷 10-18页

作者： YAO Jing YU Hongjun XU Xingyong YI Liang CHEN Guangquan SU Qiao Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Marine Sedimentology and environmental Geology First Institute of OceanographyState Oceanic Administration University of Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences

Controlled by climate changes, there were three large-scale transgressions and regressions around the Bohai Sea during the late Quaternary, which were accepted by most geologists. However, a big controversy still exists about the time when the transgressions occurred separately. In order to find out the process of the paleoenvironmental changes around the Bohai Sea in the late Quaternary, the foraminifera assemblages from a new borehole Lz908 in the southern coast of the Laizhou Bay were studied, and then the transgressive strata were indentified. Combined with accelerator mass spectrometry radiocarbon 14C（AMS14C） and optically stimulated luminescence（OSL） ages, the occurrence time of these transgressions were re-determined. The result showed that three major large-scale transgressions occurred separately at the beginning of marine isotopic stage 7（MIS7）, the last interglacial period（MIS5） and the Holocene. In addition, a small-scale transgression occurred in the mid-MIS6, and the corresponding transgressive stratum was deposited. The transgressive deposition of MIS3 was also discovered in this study. However, the characteristics of the foraminifera indicated the environment during this period was colder than that in the MIS5. By comparison with the global sea-level changes, the paleoenvironmental changes around the Bohai Sea in the late Quaternary can be consistent with the global climate changes.

关键词： foraminifera assemblage late Quaternary environmental changes Laizhou Bay Bohai Sea