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Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta
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作者 XueHua Cen Hua Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第1期30-44,共15页
The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the regio... The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development. 展开更多
关键词 Land use change Multi-scenario simulation Ecosystem services Ecological security pattern the yellow river delta Circuit theory
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Factors Influencing the Thermal Conductivity of Silt in the Yellow River Delta
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作者 YANG Xiuqing DENG Shenggui +2 位作者 GUO Lei ZHANG Yan LIU Tao 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1003-1011,共9页
The thermal conductivity of marine sediments is an important thermophysical parameter in the study of seafloor heat flow and marine engineering construction.Understanding the effect of thermal conductivity of marine s... The thermal conductivity of marine sediments is an important thermophysical parameter in the study of seafloor heat flow and marine engineering construction.Understanding the effect of thermal conductivity of marine sediments in the environment has a major engineering value and theoretical significance.In this work,a modified test method was used to measure the thermal conductivity of silt in the Yellow River Delta under different void ratios,moisture contents,temperatures,and salinities.Results showed that the thermal conductivity of silt in the Yellow River Delta decreased with the increase in the void ratio and increased with the water content.Compared with sand and clay,silt in the Yellow River Delta was the least affected by the void ratio and moisture content.Under low temperatures,the heat transfer of soil was controlled by the average velocity of the phonons;therefore,the thermal conductivity of silt in the Yellow River Estuary increased with temperature.The thermal conductivity of pore water decreased with increasing salinity.Moreover,certain salinity levels resulted in a phenomenon known as the‘compressing twin electrical layer’,which led to an increase in the contact area between soil particles.With the increase in salinity,the thermal conductivity of silt in the Yellow River Delta experiences an initial decline and a subsequent increase.The proposed thermal conductivity test method is more accurate than the existing technique,and the findings provide a basis for further study on the thermal characteristics of submarine sediments. 展开更多
关键词 silt in the yellow river delta thermal conductivity void ratio water content TEMPERATURE SALINITY
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Spatial differentiation and dynamic mechanism of micro-geomorphology based on acoustic spectrum data of the Huanghe(Yellow)River Delta
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作者 Ping LI Yongde JIN +1 位作者 Wei GAO Xiaolong ZHAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2077-2089,共13页
Submarine micro-geomorphology is a geo-morphological type occurring in shallow and surface areas of seabed.The combined relationships and distribution of the micro-geomorphology indirectly reflect coupling relationshi... Submarine micro-geomorphology is a geo-morphological type occurring in shallow and surface areas of seabed.The combined relationships and distribution of the micro-geomorphology indirectly reflect coupling relationships among the sediment deposition,dynamic environment,and geomorphologic evolution.Spatial differentiation and dynamic changes in micro-geomorphology were studied based on acoustic data interpretation from a wide range(3200 km^(2))of the Huanghe(Yellow)River delta(HRD).The combination of the sub-bottom profiler and the side-scan sonar methods allowed for the identification of submarine shallow micro-geomorphologic types,as well as their scale and spatial distributions.There were seven typical micro-geomorphologic features in the shallow and surface areas of the HRD,including buried ancient channels,stratigraphic disturbances,scour troughs,sand waves,pits,erosional remnants,and sand spots.The coupling and superposition of the sediment,sediment characteristics,seabed scouring and silting,and hydrodynamic conditions of the Huanghe River had combined effects on the patterns of micro-geomorphologic types,characteristics,and ranges.From the perspective of acoustic profile interpretations,the scale,range,and spatial locations of the microgeomorphology in the HRD revealed seasonal variation characteristics,and the spatial distributions displayed significant regional differentiation characteristics.In addition,strong stratigraphic disturbances and areas with densely distributed buried ancient channels reflected the activity and instability of the submarine shallow strata.Through the interpretation of the sub-bottom profile detection data,the diversion processes of the flow paths in the lower reaches of the Huanghe River were obtained for a certain historical period in the coastal waters of the HRD.This study further clarified the relationships between the micro-geomorphologic features and spatial combinations,which is important for research on micro-geomorphologic features and their dynamic mechanisms. 展开更多
关键词 Huanghe(yellow)river delta(HRD) micro-geomorphology acoustic reflection characteristics spatial differentiation dynamic mechanisms
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Dynamics of Bottom Boundary Layers in the Yellow River Subaqueous Delta Based on Long-Term In-Situ Observations 被引量:8
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作者 ZHU Chaoqi JIA Yonggang +4 位作者 WANG Zhenhao GUO Lei SHAN Hongxian LIU Xiaolei ZHANG Minsheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期369-370,共2页
Objective In geo-marine science,the generalized bottom boundary layer(BBL)represents a layer between sediments and seawater.The BBL plays an important role in geological,geobiochemical,geophysical and geotechnical r... Objective In geo-marine science,the generalized bottom boundary layer(BBL)represents a layer between sediments and seawater.The BBL plays an important role in geological,geobiochemical,geophysical and geotechnical research because it is the connection region of hydrosphere, 展开更多
关键词 Dynamics of Bottom Boundary Layers in the yellow river subaqueous delta Based on Long-Term In-Situ Observations
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Inversion and Prediction of Consolidation Settlement Characteristics of the Fluvial Sediments Based on Void Ratio Variation in the Northern Modern Yellow River Subaqueous Delta, China 被引量:1
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作者 LIU Xiao LIU Jie FENG Xiuli 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期545-554,共10页
The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacte... The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacted and consolidate under the geostatic stress and overburden stress. It is one of the key areas with land subsidence disasters in China, bringing a series of safety hazards to production and living. Based on the data of massive surface cores and ten drill holes ranging from 12 to 40 m obtained from the northern modern Yellow River subaqueous delta, the inversion method suitable for the calculation of consolidation settlement characteristics of the modern Yellow River subaqueous delta is discussed, and the consolidation settlement characteristics of the delta sediments are inversed and predicted in this paper. The actual void ratio of the delta sediments at the depth from 3 to 15 m shows a significant power function relationship with the depth, while the void ratio of the sediments below 15 m changes little with depth. The pre-consolidation settlement(from deposition to sampling) of the delta sediments is between 0.91 and 1.96 m, while the consolidation settlement of unit depth is between 9.6 and 14.0 cm m^(-1). The post-consolidation settlement(from sampling to stable) of the subaqueous delta sediments is between 0.65 and 1.56 m in the later stage, and the consolidation settlement of unit depth is between 7.6 and 13.1 cm m^(-1) under the overburden stress. The delta sediments with a buried depth of 3 to 7 m contribute the most to the possible consolidation settlement in the later stage. 展开更多
关键词 现代黄河三角洲 沉积率 水下 特征 比率 预言 倒置 中国
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In Situ Observation of Silt Seabed Pore Pressure Response to Waves in the Subaqueous Yellow River Delta
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作者 SONG Yupeng SUN Yongfu +3 位作者 WANG Zhenhao DU Xing SONG Binghui DONG Lifeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第5期1154-1160,共7页
The in situ pore pressure response of silt under wave action is a complex process.However,this process has not been well studied because of limited field observation techniques.The dynamic response process is closely ... The in situ pore pressure response of silt under wave action is a complex process.However,this process has not been well studied because of limited field observation techniques.The dynamic response process is closely related to engineering geological hazards;thus,this process must be urgently explored.A long-term in situ observational study of the silt sediment pore water pressure response process under wave action was conducted in the subaqueous Yellow River Delta.The response characteristics of pore water pressure are affected by tidal level and wave height.Tidal level affects the overall trend of the pore water pressure response,while wave height influences the amplitude of the pore water pressure response.This study revealed a significant lag effect in the pore pressure response.The transient pore pressure in the seabed did not respond immediately to the wave-induced pressure stress on the seabed surface.This phenomenon may be attributed to the change in soil permeability.The maximum response depth was approximately 0.5 m with a 2 m wave height.A concept model of silt soil pore pressure response under different types of wave action was developed.The accumulation rate of the pore pressure is less than the dissipation rate;thus,the developed model highlights the oscillation pore pres-sure response mechanism.The highlighted response process is of considerable importance to transient liquefaction and the startup process of pore pressure response. 展开更多
关键词 silt seabed pore pressure response in situ observation the subaqueous yellow river delta
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Dynamic Changes in the Wetland Landscape Pattern of the Yellow River Delta from 1976 to 2016 Based on Satellite Data 被引量:14
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作者 CONG Pifu CHEN Kexin +1 位作者 QU Limei HAN Jianbo 《Chinese Geographical Science》 SCIE CSCD 2019年第3期372-381,共10页
The Yellow River Delta wetland is the youngest wetland ecosystem in China's warm temperate zone. To better understand how its landscape pattern has changed over time and the underlying factors responsible, this st... The Yellow River Delta wetland is the youngest wetland ecosystem in China's warm temperate zone. To better understand how its landscape pattern has changed over time and the underlying factors responsible, this study analyzed the dynamic changes of wetlands using five Landsat series of images, namely MSS(Mulri Spectral Scanner), TM(Thematic Mapper), and OLI(Operational Land Imager) sensors in 1976, 1986, 1996, 2006, and 2016. Object-oriented classification and the combination of spatial and spectral features and both the Normalized Difference Vegetation Index(NDVI) and Normalized Difference Water Index(NDWI), as well as brightness characteristic indices, were used to classify the images in eCognition software. Landscape pattern changes in the Yellow River Delta over the past 40 years were then delineated using transition matrix and landscape index methods. Results show that: 1) from1976 to 2016, the total area of wetlands in the study area decreased from 2594.76 to 2491.79 km^2, while that of natural wetlands decreased by 954.03 km^2 whereas human-made wetlands increased by 851.06 km^2. 2) The transformation of natural wetlands was extensive: 31.34% of those covered by Suaeda heteropteras were transformed into reservoirs and ponds, and 24.71% with Phragmites australis coverage were transformed into dry farmland. Some human-made wetlands were transformed into non-wetlands types: 1.55% of reservoirs and ponds became construction land, and likewise 21.27% were transformed into dry farmland. 3) From 1976 to 2016, as the intensity of human activities increased, the number of landscape types in the study area continuously increased. Patches were scattered and more fragmented. The whole landscape became more complex. In short, over the past 40 years, the wetlands of the Yellow River Delta have been degraded, with the area of natural wetlands substantially reduced. Human activities were the dominant forces driving these changes in the Yellow River Delta. 展开更多
关键词 LANDSCAPE pattern OBJECT-ORIENTED classification LANDSAT WETLANDS yellow river delta
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Response of delta sedimentary system to variation of water and sediment in the Yellow River over past six decades 被引量:7
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作者 PENG Jun CHEN Shenliang 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期613-627,共15页
In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment ... In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The human activities were the main cause for decrease of water discharge and sediment load into the sea. From 1950 to 2005, the average annual reduction of water discharge and sediment load by means of water-soil conservation practices were 2.02×10^9 m^3 and 3.41×10^8 t respectively, and the average annual volume by water abstraction for industry and agriculture were 2.52×10^10 m^3 and 2.42×10^8 t respectively. The average sediment trapped by Sanmenxia Reservoir was 1.45×10^8 t from 1960 to 2007, and the average sediment retention of Xiaolangdi Reservoir was 2.398×10^8t from 1997 to 2007. Compared to the data records at Huanyuankou, the water discharge and sediment load into the sea decreased with siltation in the lower reaches and increased with scouring in the lower reaches. The coastline near river mouth extended and the delta area increased when the ratio of accumulative sediment load and accumulative water discharge into the sea (SSCT) is 25.4-26.0 kg/m^3 in different time periods. However, the sharp decrease of water discharge and sediment load into the sea in recent years, especially the Yellow River into the sea at Qing 8, the entire Yellow River Delta has turned into erosion from siltation, and the time for a reversal of the state was about 1997. 展开更多
关键词 yellow river water discharge sediment load human activities delta
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Spatiotemporal Variation of Plant Diversity Under a Unique Estuarine Wetland Gradient System in the Yellow River Delta, China 被引量:5
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作者 SUN Jingkuan CHI Yuan +2 位作者 FU Zhanyong LI Tian DONG Kaikai 《Chinese Geographical Science》 SCIE CSCD 2020年第2期217-232,共16页
Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spat... Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spatiotemporal variations and influencing factors of plant diversity.A unique estuarine wetland gradient system(UEWGS)consisting of soil,vegetation,heat,distance,landscape,and anthropogenic gradients was established based on the ecological features of estuarine wetland through remote sensing and field investigation methods.It resolved the complicated land surface characteristics,covered all aspects of factors influencing plant diversity,and possessed distinct spatiotemporal heterogeneities.The Yellow River Delta,the largest estuarine wetland in the northern China,was selected as the study area to demonstrate UEWGS in four seasons in 2017.A total of 123 species were recorded with considerable seasonal difference.Phragmites australis,Suaeda salsa,and Tamarix chinensis were the dominant species,and crop species also played important roles.In single effect,all aspects of gradients exerted significant influences,yet only vegetation gradient possessed significant influences in all seasons.In comprehensive effect,soil,vegetation,heat,and distance gradients showed significant gross influences.Moisture content in soil gradient and net primary productivity in vegetation gradient possessed significant net influences in all seasons and can be considered as the main driving factor and indicator,respectively,of plant diversity.The results validated the significance of UEWGS in revealing the plant diversity spatiotemporal characteristics and influencing factors,and UEWGS possessed universal applicability in the spatiotemporal analysis of plant diversity in estuarine areas. 展开更多
关键词 plant diversity SPATIOTEMPORAL variation single EFFECT comprehensive EFFECT yellow river delta
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Causes of Wetland Degradation and Ecological Restoration in the Yellow River Delta Region 被引量:9
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作者 Zhang Jian-feng Sun Qi-xiang 《Forestry Studies in China》 CAS 2005年第2期15-18,共4页
Yellow River delta (YRD) is one of the biggest deltas that there is a large area of wetland in the world. Thanks to soil (sands) sediment carried by the Yellow River, there was averagely the newly formed land 21.3... Yellow River delta (YRD) is one of the biggest deltas that there is a large area of wetland in the world. Thanks to soil (sands) sediment carried by the Yellow River, there was averagely the newly formed land 21.3 km^2 in YRD. During the development of petroleum industry and urban expansion, wetlands were degraded due to population growth, irrational land use, in addition to adverse natural eco-environment such as lower precipitation, higher soil evaporation and soil salinazation. The major ecological measures to restore degraded wetland concerned with ensuring water supply, especially establishing perfect irrigation works; protecting virgin plant communities and assisting them to regenerate by the way of site preparation, improving living surroundings; introducing salt-tolerant plants to increase vegetation species and plant coverage, thereby enhancing the capability of wetland to combat contamination and pollution through plant remediation, uptake, absorption, etc. Finally making a comprehensive land use plan, accordingly removing deleterious facilities. 展开更多
关键词 yellow river delta WETLAND RESTORATION
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Biogenic Sedimentary Structures of the Yellow River Delta in China and Their Composition and Distribution Characters 被引量:3
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作者 WANG Yuanyuan HU Bin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1488-1498,共11页
The biogenic sedimentary structures (i.e., the morphology and trace makers of burrows, tracks, trails and traces made by extant organisms) and their composition and distribution characters in different micro environ... The biogenic sedimentary structures (i.e., the morphology and trace makers of burrows, tracks, trails and traces made by extant organisms) and their composition and distribution characters in different micro environments and sub environments of the Yellow River delta in China are described. Three ichnocoenosis can be recognized: (1) Steinichnus-like ichnocoenosis, includes F, Y-shaped traces, birds' footprints on bedding plane, and Y, U-shaped burrows in intrastratal bedding, produced by Coleoptera (Heteroceridae), Orthoptera (Gryllotalpidae) and birds. It is majorly found at the delta plain point bar deposits, denoting the fresh water-related terrestrial environments. (2) Steinichnus-Psilonichnus-like ichnocoenosis, consitsis of Steinichnus-like traces on the bedding plane and Psilonichnus-like burrow which a vertical, irregularly J-, Y-, or U-shaped burrows, some of them with bulbous basal cells burrows in the intrastratal bedding, created by Coleoptera (Heteroceridae), Orthoptera (Gryllotalpidae) and crabs. It is observed in the delta plain abandoned distributary channels, and the delta front tidal creek and subaquous distributary channels, indicating the brackish water environment. (3) Palaeophycus-like ichnocoenosis, includes the round entrance burrows or with craters-shaped loop-protrusionsand and the parallel forked trails on the bedding plane, and the U, J or vertical shaped feeding burrows are in the intrastratal bedding, majorly produced by the clam (bivalve molluscs), gastropods and Nereis. It is present in the subaqueous interdistributary bay, reflecting the intertidal related environment. 展开更多
关键词 Biogenic sedimentary structures modern ichnocoenosis yellow river delta China
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Effect of Hydrological Connectivity on Soil Carbon Storage in the Yellow River Delta Wetlands of China 被引量:6
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作者 FENG Jiuge LIANG Jinfeng +3 位作者 LI Qianwei ZHANG Xiaoya YUE Yi GAO Junqin 《Chinese Geographical Science》 SCIE CSCD 2021年第2期197-208,共12页
Hydrological connectivity has significant effects on the functions of estuarine wetland ecosystem.This study aimed to examine the dynamics of hydrological connectivity and its impact on soil carbon pool in the Yellow ... Hydrological connectivity has significant effects on the functions of estuarine wetland ecosystem.This study aimed to examine the dynamics of hydrological connectivity and its impact on soil carbon pool in the Yellow River Delta,China.We calculated the hydrological connectivity based on the hydraulic resistance and graph theory,and measured soil total carbon and organic carbon under four different hydrological connectivity gradients(Ⅰ0‒0.03,Ⅱ0.03‒0.06,Ⅲ0.06‒0.12,Ⅳ0.12‒0.39).The results showed that hydrological connectivity increased in the north shore of the Yellow River and the south tidal flat from 2007 to 2018,which concentrated in the mainstream of the Yellow River and the tidal creek.High hydrological connectivity was maintained in the wetland restoration area.The soil total carbon storage and organic carbon storage significantly increased with increasing hydrological connectivity fromⅠtoⅢgradient and decreased inⅣgradient.The highest soil total carbon storage of 0‒30 cm depth was 5172.34 g/m^(2),and organic carbon storage 2764.31 g/m^(2)inⅢgradient.The hydrological connectivity changed with temporal and spatial change during 2007‒2018 and had a noticeable impact on soil carbon storage in the Yellow River Delta.The results indicated that appropriate hydrological connectivity,i.e.0.08,could effectively promote soil carbon storage. 展开更多
关键词 coastal wetland hydrological connectivity soil carbon carbon storage spatiotemporal variation the yellow river delta
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Seasonal and Spatial Variations of Macro Benthos in the Intertidal Mudflat of Southern Yellow River Delta,China in 2007/2008 被引量:2
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作者 ZOU Li YAO Xiao +4 位作者 YAMAGUCHI Hitomi GUO Xinyu GAO Huiwang WANG Kai SUN Mingyi 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期437-444,共8页
In order to examine the seasonal and spatial distributions of benthic animals in the intertidal mudflat of the southern Yellow River Delta,field investigations were carried out in 2007 and 2008 and multiple methods we... In order to examine the seasonal and spatial distributions of benthic animals in the intertidal mudflat of the southern Yellow River Delta,field investigations were carried out in 2007 and 2008 and multiple methods were applied.Results showed that,the biomass of macro benthos ranged at 0.75-1151.00 g wet m^(-2) and averaged at 156.31 g wet m^(-2),in which Mactra veneriformis accounted for 75.6%-93.4% of the total macro benthic biomass.More than 90% of macro benthos inhabited in the middle and low tide lines,and higher biomass occurred in early summer and lower in winter.Statistical analysis showed that:1)M.veneriformis growth was primarily favored at higher temperature and lower salinity;2)after long time interaction,benthic bivalve grazers led to patching distributions of Chlorophyll a(Chl a);3)macro benthic biomass positively related with Chl a when the concentration of Chl a was low,but they were negatively related when Chl a concentration was high;and 4)furthermore,the biomass of benthic bivalves peaked in the sediment with median grain size about 0.55 mm,but decreased gradually in coarse or fine sediments.The secondary productivity ranged at 0.37-283.68 g m^(-2)yr^(-1) and averaged at 47.88 g m^(-2) yr^(-1),in which 69.7% was contributed by M.veneriformis It was estimated that primary production was transformed to secondary production at a rate of 6.87%approximately,which implies that there is a local sustainability of high bivalve production. 展开更多
关键词 MACRO BENTHOS Mactra veneriformis distribution INTERTIDAL MUDFLAT SOUtheRN yellow river delta
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Remote Monitoring of Expansion of Aquaculture Ponds Along Coastal Region of the Yellow River Delta from 1983 to 2015 被引量:18
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作者 REN Chunying WANG Zongming +4 位作者 ZHANG Bai LI Lin CHEN Lin SONG Kaishan JIA Mingming 《Chinese Geographical Science》 SCIE CSCD 2018年第3期430-442,共13页
Aquaculture ponds are one of the fastest-growing land use types in valuable and fertile coastal areas and have caused serious environmental problems. Quantitative assessment of the extent, spatial distribution, and dy... Aquaculture ponds are one of the fastest-growing land use types in valuable and fertile coastal areas and have caused serious environmental problems. Quantitative assessment of the extent, spatial distribution, and dynamics of aquaculture ponds is of utmost importance for sustainable economic development and scientific management of land and water resources in the coastal area. An object-oriented classification approach was applied to Landsat images acquired over three decades to investigate the long-term change of aquaculture ponds in the coastal region of the Yellow River Delta. The results indicated that the aquaculture ponds in the study area undergone a sharp expansion from 40.38 km^2 in 1983 to 1406.89 km^2 in 2015, and the fast expansion occurred during the period of 2010–2015 and 1990–2000. Natural wetlands, especially mudflat, and cropland were main land use types contributing to the increase of aquaculture ponds. The patches of aquaculture ponds were consequently prevalence in the north of the Yellow River Estuary and landscape metrics indicated an increase of the aquaculture ponds of the study area in the quantity and complexity. The expansion of aquaculture ponds inevitably had negative effects on the coastal environment, including loss of natural wetlands, water pollution and land subsidence, etc. The results from this study provide baseline data and valuable information for efficiently planning and managing aquaculture practices and for effectively implementing adequate regulations and protection measures. 展开更多
关键词 黄河三角洲 水产业 沿海 LANDSAT 环境问题 科学管理 经济开发 区域调查
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Effects of Tidal Channels and Roads on Landscape Dynamic Distribution in the Yellow River Delta, China 被引量:2
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作者 YU Xiaojuan ZHANG Zhongsheng +2 位作者 XUE Zhenshan WU Haitao ZHANG Hongri 《Chinese Geographical Science》 SCIE CSCD 2020年第1期170-179,共10页
Landscape characters in estuarine regions generally controlled by tidal regimes and human activities like road construction.In this work,tidal channels and road construction in the Yellow River Delta(YRD)were extracte... Landscape characters in estuarine regions generally controlled by tidal regimes and human activities like road construction.In this work,tidal channels and road construction in the Yellow River Delta(YRD)were extracted by visual interpretation methods so as to decipher impacts of tidal channel development and road construction on landscape patch change during 1989–2016.Spatial distribution history of three wetlands,which covered by Phragmites australis(freshwater marsh,FM),Suaeda salsa(salt marsh,SM),and mudflats(MD)were also established.Results indicated that tidal channel,number,frequency,and fractal dimension were all the maximum in 2003,and the minimum in 1998,respectively.Road length,number,and density showed increasing trend during 1989–2016.MD were the predominant landscape type,followed by FM and SM during 1989-2016.Principal component analysis implied two extracted factors,F1 and F2,which could represent 91.93% of the total variations.F1 mainly proxied tidal channel development,while F2 represented road construction.A multiple linear regression analysis showed positive effects of both F1 and F2 on FM patch numbers and negative impacts on SM patch areaes with R^2 values of 0.416 and 0.599,respectively.Tidal channels were negatively related to MD patch numbers,while roads were positively related to that.In any case,road construction showed larger impacts on landscape type shifting than that of tidal channel development in the YRD. 展开更多
关键词 tidal channel development road construction principal component analysis multiple linear regression analysis the yellow river delta
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The comprehensive evaluation on resource environmental bearing capacity of central cities in the Yellow River Delta-A case study on Dongying City 被引量:2
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作者 WANG Kui-feng XU Meng CHEN Xiao-man 《Journal of Groundwater Science and Engineering》 2017年第4期354-363,共10页
Dongying City, which is the most important central city in the Yellow River Delta, is located in the estuary of the Yellow River. With a short land formation time, ecological environment is very weak in this area. To ... Dongying City, which is the most important central city in the Yellow River Delta, is located in the estuary of the Yellow River. With a short land formation time, ecological environment is very weak in this area. To realize the sustainable economic development of the Yellow River Delta, resource environment and resource environmental bearing capacity(REBC) must be improved. This study builds assessment system of regional REBC through resource and economic characteristics in Yellow River Delta and uses principal component analysis(PCA) method to evaluate REBC of five counties and districts in Dongying City in 2011-2015 on the dimensions of time and space. Results show that, on the time dimension, Guangrao County is ranked first, Dongying district second for four years and Hekou and Kenli districts with lower ranks in 2012-2015, indicating that more attention needs to be paid to REBC of Hekou and Dongying districts and these two districts should be included into key monitoring areas. From space scale, REBC in five counties and districts has been gradually improving. In order to further develop REBC in Dongying City, measures such as intensifying protection of urban ecological environment and developing circular economy, etc. should be implemented. 展开更多
关键词 RESOURCE environmental BEARING capacity Dongying City Comprehensive evaluation yellow river delta
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Changes of Coastal Wetland Ecosystems in the Yellow River Delta and Protection Countermeasures to Them 被引量:2
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作者 Guangzhou CUI Xuliang ZHANG +1 位作者 Zhaohui ZHANG Zongjun XU 《Asian Agricultural Research》 2013年第1期48-50,共3页
Coastal wetlands in the Yellow River Delta are typical new wetland ecosystems in warm temperate zone. In recent years, influenced by natural and human factors, these coastal wetlands in the Yellow River Delta have und... Coastal wetlands in the Yellow River Delta are typical new wetland ecosystems in warm temperate zone. In recent years, influenced by natural and human factors, these coastal wetlands in the Yellow River Delta have undergone changes of landscape fragmentation, vegetation degradation, pollution, species reduction, and harmful exotic species invasion. These changes have influenced sustainable and healthy development of marine economy of the Yellow River Delta. To protect natural ecological environment of the Yellow River Delta, the authors recommended that it should establish and improve policies, laws and regulations of wetland protection; carry out wetland resource investigation and assessment and monitoring; strengthen comprehensive protection and control of wetland; reduce wetland degradation and promote sustainable use of wetland. 展开更多
关键词 the yellow river delta COASTAL WETLAND ECOSYSTEM C
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A Preliminary Study of Rill Marks in the Yellow River Delta 被引量:3
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作者 ZHONG Jian-hua WU Kong-you NI Jin-ren 《沉积学报》 CAS CSCD 北大核心 2000年第4期527-533,共7页
In recent years, the flow of the Yellow River has often been interrupted, which has resulted in exposure of channel bars and point bars, and even extensive exposure of the riverbed. Consequently, a large number of ril... In recent years, the flow of the Yellow River has often been interrupted, which has resulted in exposure of channel bars and point bars, and even extensive exposure of the riverbed. Consequently, a large number of rill marks have developed. They are diverse in morphology. According to the hydrodynamic types of their formation, they can be grouped into 6 categories, i. e. the wave eroded, backwash, seepage, rain eroded, water drainage and runoff rill marks. Morphologically, they can be divided into more than ten types: the linear, tooth shaped, comb shaped, fence like, ear like, braided, branched, leaf like, flower like, root like, dendritic, net like, radial etc. Their cross sections include the broad u type (the width/depth ratio is over 2, and may reach 10—20), U type (width/depth ratio from 1 to 2), V type, Ω type and ( type. Their occurrences may be attributed to the variations in composition, grain size, color, fabric and morphology. They have 5 scales: the micro scale (length and width within 1 cm), small scale (length and width within 10 cm), medium scale (length and width ranging from 10—100cm), large scale (length and width 1—5 m) and giant-scale (length or width over 5 m). 展开更多
关键词 rill marks yellow river delta
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Increased salinity and groundwater levels lead to degradation of the Robinia pseudoacacia forest in the Yellow River Delta 被引量:2
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作者 Chaoxia Lu Chen Zhao +3 位作者 Jing Liu Kailun Li Baoshan Wang Min Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1233-1245,共13页
Forest degradation is a worldwide problem,although its causes vary due to geographical and climatic differences and man-made causes.In recent years,the Robinia pseudoacacia forest in the Yellow River Delta has suffere... Forest degradation is a worldwide problem,although its causes vary due to geographical and climatic differences and man-made causes.In recent years,the Robinia pseudoacacia forest in the Yellow River Delta has suffered severe degradation.The causative mechanisms were investigated in the field over two years,and the results show that increased forest degradation was reflected by increased tree mortality,high leaf and soil sodium salt levels and groundwater depth.Average tree diameters decreased,and leaf chlorophyll and soil microbial contents decreased.Redundancy discriminate analysis(RDA)showed that degradation of the forest was correlated positively with soil salt content,but negatively with groundwater depth.Correlation analysis showed that 0.79%–0.95%soil salt content and above 1.20 m groundwater depth caused the death of R.pseudoacacia trees due to localized anthropogenic economic activities,such as rice farming,that disrupted the original water–salt balance.Measures are recommended to prevent further degradation and restore degraded forests. 展开更多
关键词 Forest degradation Groundwater depth Robinia pseudoacacia forest Soil salt content the yellow river delta
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Sedimentary facies of the subaqueous Changjiang River delta since the late Pleistocene 被引量:3
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作者 徐涛玉 石学法 +5 位作者 王国庆 乔淑卿 杨刚 刘升发 王旭晨 赵泉鸿 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1107-1119,共13页
自从迟了的更新世,水下的 Changjiang (Yangtze ) 河三角洲的沉积外形为二地上凿穿, CJK07 和 CJK11 基于岩性学和有孔虫类分析被学习,与标明日期的 14C 一起。四沉积外形被识别的、也就是河的、潮汐的公寓,近海,并且 prodelta 外... 自从迟了的更新世,水下的 Changjiang (Yangtze ) 河三角洲的沉积外形为二地上凿穿, CJK07 和 CJK11 基于岩性学和有孔虫类分析被学习,与标明日期的 14C 一起。四沉积外形被识别的、也就是河的、潮汐的公寓,近海,并且 prodelta 外形。河的沉积外形由河的隧道组成落后扔,河的点酒吧扔,并且泛滥平原扔没有 benthic 有孔虫类一般来说显示出一个鳍向上的序列。生硬泥土的层在核心 CJK07 躺河的存款,显示在最后冰川的最大值(LGM ) 期间的长期的暴露环境。在在 13-7.5 cal ka BP 附近的冰期后的海平面的上升期间,潮汐的扁平的外形在核心 CJK11 被扔,由丰富的淤泥泥土两行诗描绘了。能在不同盐分之环的种类统治 subtidal 公寓有孔虫目的集合,当几乎没有有孔虫类完全在 intertidal 被发现时。近海当海水平在 7.5 cal ka BP 附近到达了它的高水平时,环境是主要沉积环境,与 10 的最大的累积率, mm/a 在核心 CJK11 发现了。自从 3 cal ka BP, Prodelta 沉积在核心 CJK11 被扔了,在 Changjiang 河三角洲的形成以后。在在核心 CJK07 和 CJK11 之间的沉积外形的差别由于他们的地点:当核心 CJK11 在 LGM 期间在一条切入的山谷时,核心 CJK07 在一块河间地。而且,核心 CJK07 标明日期的 AMS 14 C 给穷人看按年代先后的顺序,显示沉积被自从在核心 CJK07 的 7.7 cal ka BP 被 Changjiang 河三角洲 depocenter 的向南方的移动引起的现代水动力学力量离开侵蚀,扔的强壮的潮汐的水流和那沉积重做。 展开更多
关键词 长江三角洲 晚更新世 沉积相 水下 河流沉积物 底栖有孔虫 末次盛冰期 海平面上升
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