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Simulation and Analysis of Land System Structure Changes in Huang-Huai-Hai Plain Area 被引量:6
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作者 邓祥征 战金艳 +2 位作者 苏红波 姜群鸥 迟百余 《Agricultural Science & Technology》 CAS 2007年第3期45-52,共8页
The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the d... The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the driving-force for the dynamic change mechanism of land system, such as natural, social and economic factors. The future dynamic changes of land system in Huang - Huai - Hai Plain on each 1 km cell during 2000 to 2020 were stimulated by combining the dynamic changes of land system on each 1 km cell with different situations. The research indicated that the dynamic changes of land system structure changed mainly from the cultivated areas to building areas and industrial areas, and forest areas increased during this period. Although the revolutions of land system structure were different during 2000 to 2020 with the different referrence standard, ecological protection and economic development, the primary dynamic changes of land system structure were that the increase of building land areas with the decline cuhivaled land areas and the increase of woodlands. 展开更多
关键词 LAND Land system Land system structure Land system structure change Land use Dynamic simulation Huang- Huai -Hai Plain
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八极拳精英传奇 被引量:4
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作者 朱宝德 吕甫琴 《中华武术》 2004年第2期44-47,共4页
在中国武术界,一谈到八极拳的源流,人们都要提到八极拳始祖吴钟。
关键词 八极拳 武术家 吴钟 曹井田 黄土海 王中泉 强瑞清 李书文 大枪技艺 季云龙
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The influence of plant root system architectural properties upon the stability of loess hillslopes,Northeast Qinghai,China 被引量:21
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作者 FU Jiang-tao HU Xia-song +5 位作者 BRIERLEY Gary QIAO Na YU Qin-qin LU Hai-jing LI Guo-rong ZHU Hai-li 《Journal of Mountain Science》 SCIE CSCD 2016年第5期785-801,共17页
To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plate... To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plateau (QTP), indoor direct shear tests have been conducted on the remolded rooted soil of three shrubs. Test results show that root system architectural indices (root area ratio (RAR), root length density (RLD) and root density (RD)) of the shrubs decline with depth and the relationship between RAR, RD and depth is exponential, while a power relationship describes the relationship between RLD and depth. The cohesion force of remolded rooted soil for the shrubs initially increases with depth, but it then demonstrates a slightly decreasing trend, which can be described with a power relationship. Power relationships also describe relationships between cohesion force and RAR, RLD and RD for the shrubs. As the growth period increases from lO to 17 months, the incremental increase in RAR is 48.32% ~ 21o.25% for Caragana korshinskii Kom and 0.56% ~ 166.85% for ZygophyUum xanthoxylon (Bunge) Maxim. This proportional increase is notably larger than that for RLD and RD. The increment in RAR is marginally greater for C. korshinskff than it is for Z. xanthoxylon. Correspondingly, the cohesion force incremental rates of remolded rooted soil for C. korshinskii and Z. xanthoxylon are 12.41% ~ 25.22% and 3.45% ~ 17.33% respectively. Meanwhile, as root content increases, the contribution by roots to cohesion force increases markedly until a threshold condition is reached. 展开更多
关键词 Cold region Semiarid region Soil reinforcement Hillslope stability Root system architectural indices Plateau
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Modeling Soil Organic Matter Dynamics Under Intensive Cropping Systems on the Huang-Huai-Hai Plain of China 被引量:6
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作者 LEI Hong-Jun LI Bao-Guo +3 位作者 BAI You-Lu HUANG Yuan-Fang Lü Yi-Zhong LI Gui-Tong 《Pedosphere》 SCIE CAS CSCD 2006年第4期409-419,共11页
A modified CQESTR model, a simple yet useful model frequently used for estimating carbon sequestration in agricultural soils, was developed and applied to evaluate the effects of intensive cropping on soil organic mat... A modified CQESTR model, a simple yet useful model frequently used for estimating carbon sequestration in agricultural soils, was developed and applied to evaluate the effects of intensive cropping on soil organic matter (SOM) dynamics and mineralization as well as to estimate carbon dioxide emission from agricultural soils at seven sites on the Huang-Huai-Hai Plain of China. The model was modified using site-specific parameters from short- and mid-term buried organic material experiments at four stages of biomass decomposition. The predicted SOM results were validated using independent data from seven long-term (10- to 20-year) soil fertility experiments in this region. Regression analysis on 1 151 pairs of predicted and measured SOM data had an r2 of 0.91 (P≤0.01). Therefore, the modified model was able to predict the mineralization of crop residues, organic amendments, and native SOM. Linear regression also showed that SOM mineralization rate (MR) in the plow layer increased by 0.22% when annual crop yield increased by 1 t ha^-1 (P ≤ 0.01), suggesting an improvement in SOM quality. Apparently, not only did the annual soil respiration efftux merely reflect the intensity of soil organism and plant metabolism, but also the SOM MR in the plow layer. These results suggested that the modified model was simple yet valuable in predicting SOM trends at a single agricultural field and could be a powerful tool for estimating C-storage potential and reconstructing C storage on the Huang-Huai-Hai Plain of China. 展开更多
关键词 carbon dioxide emission intensive cropping system MODELING modified CQESTR model soil organic matter
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Luminescence chronology and age model application for the upper part of the Chumbur-Kosa loess sequence in the Sea of Azov, Russia 被引量:1
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作者 CHEN Jie YANG Tai-bao +4 位作者 G.G.MATISHOV A.A.VELICHKO ZENG Biao HE Yi SHI Pei-hong 《Journal of Mountain Science》 SCIE CSCD 2018年第3期504-518,共15页
A reliable chronology is essentially critical for correlating loess records with other paleoenvironmental time series, as well as for continuing improvements in the reconstruction of paleoenvironment and paleoclimate ... A reliable chronology is essentially critical for correlating loess records with other paleoenvironmental time series, as well as for continuing improvements in the reconstruction of paleoenvironment and paleoclimate changes. It is exactly that the scarcity of chronologies across the Sea of Azov has limited the interpretation of climatic and environmental information in the East European Plain. In view of this, this paper conducted an exploratory study to investigate whether the optically stimulated luminescence(OSL) dating of medium-grained quartz could be used to obtain a set of chronologies and the age models could be used to establish an independent time scale since the Late Pleistocene for the Sea of Azov loess. The results showed that an internally consistent set of optical ages for the Azov loess deposited up to ~76 ka. In addition, the ages developed based on magnetic susceptibility and grain size ages models showed good comparability with independent OSL ages at an acceptable range, suggesting that it might be practicable to establish an independent time scale using age models at the Sea of Azov loess, at least for the uppermost part of the Chumbur-Kosa section. Comparison with the ages based on two age models,the grain size ages using fine-grain fractions may provide a more reliable chronological sequence at the Azov loess since the Late Pleistocene. With the help of absolute ages and climate proxies(magnetic susceptibility and grain size), paleoclimatic change in the Sea of Azov have been traced for the Late Pleistocene. 展开更多
关键词 Optical dating Age models LOESS Late Pleistocene Sea of Azov
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Paleoclimatic record from Chumbur-Kosa section in Sea of Azov region since Marine Isotope Stage 11 被引量:1
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作者 LIANG Ye YANG Tai-bao +6 位作者 Andrey Aleksevitch VELICHKO ZENG Biao SHI Pei-hong WANG Lin-dong HE Yi CHEN Jie CHEN Yu 《Journal of Mountain Science》 SCIE CSCD 2016年第6期985-999,共15页
Abstract: Loess-paleosol sequences preserve records of climatic change during the Quaternary, which is important for paleoclimate study. In this study, a loess-palaeosol sequence from the Chumbur- Kosa (CK) site in... Abstract: Loess-paleosol sequences preserve records of climatic change during the Quaternary, which is important for paleoclimate study. In this study, a loess-palaeosol sequence from the Chumbur- Kosa (CK) site in the Sea of Azov region was investigated to reconstruct climatic variability during the Marine Isotope Stage (MIS)11- MIS 1, using proxies of grain size (GS), magnetic susceptibility (xlf and Xfd(%)), carbonate content (CaCO3%) and soil color The results enabled formulation of a detailed description of the climatic characteristics related to each individual layer. The sequence indicates that the paleoclimate shifted progressively towards increasingly cooler, somewhat drier conditions. The CK section may thus be ideal for reconstructing climatie eondifions during the Middle and Late Pleistocene in the Sea of Azov region. However, the )Of value of paleosol $2 in the CK profile indicates different characteristics from the other paleosol layers, dilution of carbonate resulting from carbonate leaching in L2 may be the main reason for the decrease in magnetic susceptibility. Furthermore, through simple analysis part of the environmental evolution process in the Sea of Azov region and Serbia during Middle and Late Pleistocene cycles. The climate cycle expressed by Xfd(%) and Xlf variations show similar patterns, with rapidly alternating cold and warm intervals. Nevertheless, although the two areas had different climatic regimes, geographical settings, and loess source areas, both exhibited similar climate change trends since the MIS 11. 展开更多
关键词 LOESS PALEOSOL Magnetic susceptibility PALEOCLIMATE Sea of Azov
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Features of Clay Minerals in the YSDP102 Core on the Continental Shelf of the Southeast Yellow Sea
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作者 JIANGXuejun QUGaosheng LIShaoquan 《Journal of Ocean University of China》 SCIE CAS 2004年第2期201-207,共7页
Ninety-eight clay mineral samples from the YSDP102 core were analyzed by x-ray diffractometer to study the four clay minerals: illite, chlorite, kaolinite and smectite. Twenty-eight samples had been analyzed on the la... Ninety-eight clay mineral samples from the YSDP102 core were analyzed by x-ray diffractometer to study the four clay minerals: illite, chlorite, kaolinite and smectite. Twenty-eight samples had been analyzed on the laser particle-size analyzer to reveal the particle features of the sediments. Distribution of the clay minerals and the particle characteristics in the YSDP102 core show that the core experienced three different depositional periods and formed three different sedimentary intervals due to different sediment sources and different depositional environments. Features of the clay minerals and the heavy minerals in the YSDP102 core indicate that coarse-grained sediments and fine-grained sediments result from different sources. The Yellow Sea Warm Current has greatly influenced the sedimentary framework of this region since the current’s formation. 展开更多
关键词 clay minerals sediment sources Yellow Sea Warm Current depositional environment
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Using Geochemistry of Rare Earth Elements to Indicate Sediment Provenance of Sand Ridges in Southwestern Yellow Sea 被引量:5
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作者 LI Lei SU Jinbao +1 位作者 RAO Wenbo WANG Yigang 《Chinese Geographical Science》 SCIE CSCD 2017年第1期63-77,共15页
The Jianggang Harbour-centered radial sand ridge(RSR) is the largest sand body in the Yellow Sea. Its formation and evolution are of interest for scientists of various fields; however, the sediment provenance is uncer... The Jianggang Harbour-centered radial sand ridge(RSR) is the largest sand body in the Yellow Sea. Its formation and evolution are of interest for scientists of various fields; however, the sediment provenance is uncertain. In this study, rare earth element(REE) geochemical compositions of the RSR sediments together with their potential sources are investigated to identify the provenance of the RSR sediments. The typical parameters((La/Yb)_N,(La/Sm)_N and(Gd/Yb)_N) as well as the upper continental crust-normalized patterns of REEs can only be associated with source rocks, and thus can be used as effective tracers for the origin and sources of sediments. However, the REE contents of sediments are affected by many factors, such as particle sorting and chemical weathering. Onshore RSR sediments are different in REE geochemical composition from offshore RSR sediments to some extent, suggesting that not all of the offshore RSR sediments have the same sources as the onshore RSR sediments. Meanwhile, the sediments adjacent to the northeast of Cheju Island and at Lian Island near the Lianyun Harbour were not the source of the RSR sediments due to their distinctive REE patterns, dEu,(La/Yb)_N,(Gd/Yb)_N and(La/Sm)_N. The Korean river sediments could be dispersed to the Jiangsu Coast slightly impacting the fine fractions of the RSR sediments, particularly the offshore RSR sediments. Additionally, geochemical comparisons show that the modern Yellow River was responsible for the onshore RSR sediments, whereas the sediment loads from the Yangtze River could serve as a major contributor to the RSR, particularly the offshore RSR. In addition, the offshore RSR could also be partly fed by an unknown source due to some high values of(La/Yb)_N,(La/Sm)_N and La contents differing from those of the Chinese and Korean river sediments. 展开更多
关键词 rare earth elements(REEs) sediment provenance radial sand ridges(RSRs) potential sources Yellow Sea
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On the geo-basis of river regulation in the lower reaches of the Yellow River 被引量:3
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作者 LIU GuoWei 《Science China Earth Sciences》 SCIE EI CAS 2012年第4期530-544,共15页
This paper investigates the important scientific problem of river regulation strategies in the lower reaches of the Yellow River, and discusses the "geo-basis" of river regulation. The concept of a geo-basis... This paper investigates the important scientific problem of river regulation strategies in the lower reaches of the Yellow River, and discusses the "geo-basis" of river regulation. The concept of a geo-basis to river regulation in the lower Yellow River was discussed in terms of subsidence and sedimentation features of the fiver plain; channel features, erosion characteristics of the Loess Plateau and storm-flood features of the middle and lower reaches. The geographic features of the lower Yellow River have gradually changed since the Holocene but there has been no fundamental change. Based on an analysis of the geo-attributes of the lower reaches of the Yellow River, several conclusions on its river regulation were made. The release of sediment should be the first measure of river regulation because of deposition in the lower reaches. The fiver channels should be provided with adequate space for wandering in the lower reaches. The tail river should be also provided with necessary wandering space because of weak marine dynamics in the estuary area and changes in the delta. Because the erosion environ- ment of the Loess Plateau will not fundamentally change, river harnessing of the middle reaches should focus on improving the plateau morphology, which can be done by reducing the fragmentation of terrain and building a planation surface. Eco- remediation should focus on converting farmland to grassland. There may be extreme floods in the future, as has occurred pre- viously, thus an extreme flood defense system should be considered for the lower reaches. A periodic law for regulation in the Yellow River is discussed. We also discuss how the current use of the lower reaches of the Yellow River is unsustainable and it is urgent to research artificial rechanneling and the creation of new flow paths for the lower reaches. 展开更多
关键词 RIVER geo-attributes river regulation the Yellow River floods
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