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Analysis of Stakeholders in Tourism Development of the Miao Village in Xijiang
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作者 刘春莲 李茂林 《Journal of Landscape Research》 2010年第11期55-57,共3页
Through applying stakeholder theory and analyzing the game,interest expectations and interest conflicts among stakeholders in tourism development of the Miao Village in Xijiang,Guizhou Province,approaches of coordinat... Through applying stakeholder theory and analyzing the game,interest expectations and interest conflicts among stakeholders in tourism development of the Miao Village in Xijiang,Guizhou Province,approaches of coordinating interest relations among these stakeholders are summarized. 展开更多
关键词 STAKEHOLDER VILLAGES of MINORITY groups xijiang
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Stable isotopic composition of riverine dissolved inorganic carbon of the Xijiang River Inner Estuary 被引量:10
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作者 JIAO Shulin TAO Zhen +4 位作者 GAO Quanzhou LIU Kun SHE Jianwei DING Jian LIU Zufa 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期363-372,共10页
For researching the spatio-temporal variation of the stable isotopic composition of the riverine dissolved inorganic carbon(DIC),we had carried out a survey throughout the hydrologic year during which theδ^13CDIC o... For researching the spatio-temporal variation of the stable isotopic composition of the riverine dissolved inorganic carbon(DIC),we had carried out a survey throughout the hydrologic year during which theδ^13CDIC of the surface water and its physicochemical parameter were examined along the Xijiang River Inner Estuarine waterway from September 2006 to June 2007.There was a striking seasonal variation on the averageδ^13CDIC,as the averageδ^13CDIC in summer(-13.91‰)or autumn(-13.09‰)was much less than those in spring(-11.71‰)or winter(-12.26‰).The riverineδ13C DIC was controlled by decomposed condition of the riverine organic matter linking the seasonal variation of the physicochemical parameter in the surface water according to the correlation analysis which indicated notable relations betweenδ^13CDIC and water temperature(p=0.000;r=-0.569)or betweenδ^13CDIC and oxide-reduction potential(p=0.000;r=0.646).The striking positive correlation between δ^13CDIC and the sampling distance happened in the summer rainy season,while striking negative correlation happened in the spring dry season,indicating that river-sea interaction influenced water physicochemical parameters and controlled the riverine DIC property in the survey waterway.In view of the riverineδ^13CDIC decreasing for the decomposition of the terrestrial organic matter in the rainy season in summer and increasing for the briny invaded zone extending in the spring dry season along the waterway from the Makou gauging station to the Modaomen outlet,theδ^13CDIC spatio-temporal variation was closely related to the geographical environment of the Xijiang drainage basin. 展开更多
关键词 xijiang River Inner Estuary dissolved inorganic carbon stable isotopic carbon spatio-temporal variation
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Temporal and Spatial Variability of Dissolved Organic Carbon Concentration in the Xijiang River, South China 被引量:4
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作者 TAO Zhen GAO Quanzhou +5 位作者 GUO Wenping WANG Zhengang ZHANG Yongling XIE Chenji HUANG Xiakun ZHONG Hongwei 《Journal of Mountain Science》 SCIE CSCD 2011年第5期694-703,共10页
A whole year analysis of riverine dissolved organic carbon (DOC) concentrations in the Xijiang River (XJR), South China, showed that the mean riverine DOC concentration (1.24 mg L-1) in the XJR was notably lower than ... A whole year analysis of riverine dissolved organic carbon (DOC) concentrations in the Xijiang River (XJR), South China, showed that the mean riverine DOC concentration (1.24 mg L-1) in the XJR was notably lower than the averaged value (5.75 mg L-1) of the global riverine DOC concentration in several major rivers. There is an inconspicuous monthly fluctuation of the DOC signal in the XJR, but on a semi-yearly time scale, however, the riverine DOC concentration had significant difference between hydrological seasons. The DOC level during the flood season (1.18 mg L-1) was less than that during the non-flood season (1.40 mg L-1). Owing to the concomitance of the flushing and dilution effects of the runoff during the high-water period, the variation of riverine DOC concentration with discharge in the XJR differed from that reported in many other major rivers. The DOC export flux above the city of Wuzhou was about 0.62× 106 g C km-2 yr-1. The DOC transported during the "056" Massive Flood period comprised 30.35% of the annual total, while the discharge accounted for 36.32% of the total annual flow. The characteristics in riverine DOC concentration in the XJR were attributed to the combined effect of the geomorphologic, monsoon climatic and hydrological processes as well as land-use within the drainage basin. 展开更多
关键词 Export flux Hydrological processes Massive flood Riverine dissolved organic carbon The xijiang River
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Sulfate sources constrained by sulfur and oxygen isotopic compositions in the upper reaches of the Xijiang River,China 被引量:2
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作者 Jing Liu Siliang Li +4 位作者 Jun Zhong Xuetao Zhu Qingjun Guo Yunchao Lang Xiaokun Han 《Acta Geochimica》 EI CAS CSCD 2017年第4期611-618,共8页
While it is critical to accurately understand the sources and transformation of sulfate based on time-series analysis, there are limited studies on temporal variation of sulfate in rivers and on rock weathering by sul... While it is critical to accurately understand the sources and transformation of sulfate based on time-series analysis, there are limited studies on temporal variation of sulfate in rivers and on rock weathering by sulfuric acids.We conducted a monthly sampling campaign in the Beipan, Nanpan, and Hongshui Rivers over the course of one hydrological year. This study examined seasonal variations in riverine sulfate impacted by the monsoon climate in the upper reaches of the Xijiang River basin. In general, the SO_4^(2-) contents in these rivers dropped from relatively high levels to low values during the high-flow season, in response to increasing discharge. The sulfate was generally enriched in heavy isotopes during the low-flow season compared to the high-flow season. The calculated results indicate that the riverine sulfate was mainly derived from sulfide oxidation, but that evaporite dissolution could be an important source during the low-flow season, based on isotopic evidence. Mine drainage is likely an important source of sulfate to these rivers during the high-flow season due to contributions from fast surface flow, which responds to frequent heavy rain in monsoonal climate regions. Arelatively high proportion of HCO_3^- was found to be derived from rock weathering by sulfuric acid during the high-flow season when compared to that observed during the low-flow season. The results suggest that approximately one quarter of the HCO_3^- in the Hongshui River originated from carbonate weathering by sulfuric acid derived from the oxidation of sulfide. Such information on the specific dual isotopic characteristics of riverine sulfate throughout a hydrological year can provide unique evidence for understanding the temporal variability of sulfate concentrations and weathering processes in rivers. 展开更多
关键词 Sulfur isotope Oxygen isotope Riverine sulfate Carbonate weathering xijiang River
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ANALYSES OF INTRASEASONAL OSCILLATION CHARACTERISTICS OF FLOOD-CAUSING RAINSTORMS IN XIJIANG RIVER VALLEY DURING THE ANNUALLY FIRST RAINING SEASON IN THE PAST YEARS 被引量:1
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作者 罗秋红 纪忠萍 +2 位作者 吴乃庚 蔡洁云 孙汉明 《Journal of Tropical Meteorology》 SCIE 2011年第2期136-146,共11页
Based on the daily precipitation data of nine stations representing the Xijiang River valley and the National Center for Environmental Prediction/National Center for Atmospheric Research (USA) reanalysis data, this st... Based on the daily precipitation data of nine stations representing the Xijiang River valley and the National Center for Environmental Prediction/National Center for Atmospheric Research (USA) reanalysis data, this study uses the wavelet analysis and band-pass filter methods to investigate the atmospheric intraseasonal oscillation characteristics of flood-causing rainstorms in the valley during the annually first raining seasons in 1968, 1994, 1998, 2002 and 2005. Results show that the daily precipitation in the valley exhibits significant quasi-biweekly (10 to 20 days) oscillations. The flood-causing rainstorms in the valley were mainly associated with the confluence of low-frequency warm and humid airflow in the lower latitudes and cold and dry airflow in the higher latitudes. The low-frequency vortexes were propagating or in control when this type of rainstorms took place over the valley, being favorable for the convergence of moisture at lower levels and thus vital to the formation of the rainstorms. 展开更多
关键词 rainstorms intraseasonal oscillation filter xijiang River valley annually first raining season
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THE DIFFERENCE OF ECONOMIC FUNCTION AND THE TRENDS OF INDUSTRIAL DEVELOPMENT IN CENTRAL CITIES ALONG THE XIJIANG RIVER
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作者 Chi-mei Liao Lan Li Ling-yun Zeng 《Chinese Geographical Science》 SCIE CSCD 2000年第4期48-55,共8页
The Xijiang River is an important link between Guangdong Province and the Guangxi Zhuang Autonomous Region, and a tie between its basin and the world. The zone which consists of 12 cities backing onto the main channel... The Xijiang River is an important link between Guangdong Province and the Guangxi Zhuang Autonomous Region, and a tie between its basin and the world. The zone which consists of 12 cities backing onto the main channel, including Guangzhou, Shenzhen, Nanning and Bose, etc., is an economic growing point and industry spreading origin of all the river basin. According to the nonagricultural population scale, these cities are divided into four grades. By analyzing seven indexes (GDP, nonagricultural population, gross values of industrial output, postal and telecommunication service scales, social commodity total volume of retail sales,resident saving balance, student sum in college), these cities are divided into four kinds of growing points, which show the different radiating function in different regions. The 12 cities, which have differed obviously in industry structure and the scale of the secondary& tertiary industry, are divided into three industry steps. By studying the difference of urban industrial function specialization in the 12 cities, the problems have been revealed in the urban industry structure developing. They are about the lower levels of the three industries, the lack of coordination with city status in the development of specialized departments, the similarity of the industry structure and the specialized departments, and so on. Based on the pattern of urban industry structure developing and the theory of regional economic step transferring, some suggestions have been discussed. They include the trends of cities’ industry developing, the change and improvement of the percentage of the three industries, the adjustment and amendment of the region and industry structure, and the labor division and location of cities manufacture. 展开更多
关键词 the xijiang RIVER CENTRAL CITIES industry structure TREND of specialization|
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Wooden Wall Construction of Traditional Miao Stilted Buildings: A Case Study of Xijiang Miao Village in Guizhou
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作者 GAO Pei GAO Wanglei 《Journal of Landscape Research》 2019年第2期68-70,共3页
Wooden walls of traditional stilted buildings of Miao Nationality show outstanding regional characteristics. Taking the well-preserved traditional stilted buildings in Xijiang Miao Village for example, this paper focu... Wooden walls of traditional stilted buildings of Miao Nationality show outstanding regional characteristics. Taking the well-preserved traditional stilted buildings in Xijiang Miao Village for example, this paper focused on the construction units of the wooden wall, and the hierarchy of wooden wall construction, concluded spatial forms of the wooden wall, in order to explore the indigenous construction culture in the wooden wall system, protect and inherit the culture; seek for the ways of expressing national and regional characteristics in the modern architectural designs of relevant cultural regions. 展开更多
关键词 Stilted buildings WOODEN WALL CONSTRUCTION xijiang MIAO VILLAGE
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Water geochemistry and boron isotope in the Xijiang River,SW China
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作者 Zhiqi ZHAO Congqiang LIU Zhifang XU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期271-271,共1页
关键词 同位素 河流 水土流失 水地球化学
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Regional Ecological Vulnerability Assessment of the Guangxi Xijiang River Economic Belt in Southwest China with VSD Model 被引量:8
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作者 李平星 樊杰 《Journal of Resources and Ecology》 CSCD 2014年第2期163-170,共8页
The interactive effects of natural and human factors on ecosystems have been well studied, and the quantitative assessment of large-scale ecological vulnerability caused by natural and human factors is now one of the ... The interactive effects of natural and human factors on ecosystems have been well studied, and the quantitative assessment of large-scale ecological vulnerability caused by natural and human factors is now one of the most active topics in the ifeld. Taking the Guangxi Xijiang River Economic Belt in southwest China (GXEB) as a case study, we assess ecological vulnerability based on the Vulnerability Scoping Diagram (VSD) model. The indices system is decomposed into three sub objects, ten elements and 25 indicators layer by layer, which included factors from both natural and human ifelds. Results indicate that zones with lower, middle-lower, middle, middle-higher and higher vulnerability account for 11.31%, 22.63%, 27.60%, 24.39%, and 14.07%, respectively. The western and eastern parts of GXEB are more vulnerable than the central part and the mountain and urban areas are of higher vulnerability than the basins and river valleys. Compared with a vulnerability assessment based on natural factors only, it is concluded that human activities indeed cause the transition from naturally stable zones to vulnerable zones. The nature-dominated vulnerable zones are different with human-dominated ones in size and distribution, the latter being smaller, more scattered and distributed in urban areas and their surroundings. About 53%of total construction land is distributed in zones with middle and middle-higher ecological vulnerability;less vulnerable zones should attract construction in the future. Relevant suggestions are proposed on how to reduce vulnerability according to inducing factors. The VSD model has a signiifcant advantage in the quantitative evaluation of ecological vulnerability, but is insufficient to distinguish nature- or human-dominated vulnerability quantitatively. 展开更多
关键词 ecological vulnerability interaction of natural and human factors VSD model Guangxi xijiang River Economic Belt in China
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基于极点对称模态分解的中长期径流预报组合模型
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作者 李继清 刘洋 +1 位作者 张鹏 陈景 《水力发电学报》 CSCD 北大核心 2024年第7期30-40,共11页
为提高径流预报精度,解决径流序列分解后高频分量波动范围大、预报精度差的问题,基于极点对称模态分解法(ESMD)平稳化处理技术将径流序列分解,通过分析不同频率分量特征,择优选取预报方法,结合粒子群优化最小二乘支持向量机(PSO-LSSVM)... 为提高径流预报精度,解决径流序列分解后高频分量波动范围大、预报精度差的问题,基于极点对称模态分解法(ESMD)平稳化处理技术将径流序列分解,通过分析不同频率分量特征,择优选取预报方法,结合粒子群优化最小二乘支持向量机(PSO-LSSVM)全局优化和非线性建模能力及适应性强的特点,对高频分量进行预测,利用BP神经网络非线性映射能力和逼近任意非线性函数的优势对中低频分量和趋势分量进行预报,构建了ESMD-PSO-LSSVM-BP组合预报模型,对西江干流上中下游三座水文站的年、月尺度径流开展中长期径流预报。结果表明,对不同频率分量采用不同预报方法的组合模型可以有效提高径流预报精度。 展开更多
关键词 西江流域 径流预报 非平稳序列 组合预报模型 极点对称模态分解
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西北江下游河流底栖动物群落健康评价
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作者 肖许沐 马卓荦 +1 位作者 蒋任飞 王赛 《环境监测管理与技术》 CSCD 北大核心 2024年第4期30-35,共6页
2020年12月在西北江下游河流设置11个采样点,调查底栖动物群落结构,应用底栖动物完整性指数(B-IBI)评价河流健康状况,并分析B-IBI值与环境因子的关系。结果表明,参照点位的B-IBI值在0.59~4.00之间,处于中等—优状态;受损点位的B-IBI值在... 2020年12月在西北江下游河流设置11个采样点,调查底栖动物群落结构,应用底栖动物完整性指数(B-IBI)评价河流健康状况,并分析B-IBI值与环境因子的关系。结果表明,参照点位的B-IBI值在0.59~4.00之间,处于中等—优状态;受损点位的B-IBI值在0~0.82之间,处于很差—良好状态,其中较差和很差状态占比为87.5%。氨氮浓度与B-IBI值呈现极显著的负相关性,降低水污染负荷是促进底栖动物群落恢复健康的有效途径。在水质已经实现好转的基础上,可通过营造河底卵石生境来促进底栖动物群落恢复,同时也应加强河岸带的修复。 展开更多
关键词 底栖动物 群落结构 底栖动物完整性指数(B-IBI) 河流健康评价 西北江下游
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广东省主要江河68年径流量年际变化特征分析
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作者 王进 李湘姣 +1 位作者 杨琳 林凯荣 《广东水利水电》 2024年第9期1-8,共8页
基于广东省西江、北江、东江、韩江、鉴江等5条主要江河1956—2023年共68 a的径流量资料,分析了径流量的基本特征和趋势性、自相关性、随机性和空间相关性等变化特性。结果表明,5条江河径流量的年际变化总体较大;西江的平水年较多,而其... 基于广东省西江、北江、东江、韩江、鉴江等5条主要江河1956—2023年共68 a的径流量资料,分析了径流量的基本特征和趋势性、自相关性、随机性和空间相关性等变化特性。结果表明,5条江河径流量的年际变化总体较大;西江的平水年较多,而其他江河的特丰年和特枯年较多;5条江河径流量的年际变化趋势性不明显,北江、鉴江、西江呈不显著上升趋势,东江、韩江呈不显著下降趋势;径流量序列的年际自相关性很低,接近于纯随机性,旱涝切换的规律性不强;西江与其他4条江河的年径流量序列的互相关性较弱,互补性较强;北江、东江和韩江的年径流量序列的互相关性较强,同丰同枯现象明显;鉴江的年径流量序列与其他江河的互相关性也较弱。 展开更多
关键词 广东省 径流 年际变化 趋势性 相关性 随机性 西江 北江 东江
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文化自信视域下西江苗寨苗绣产业复兴实践研究
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作者 梅军 杨武学 《兴义民族师范学院学报》 2024年第4期63-70,共8页
民族地区乡村振兴是实现中国式现代化的重要组成部分,而文化自信是民族地区乡村振兴的重要动力和有力保障,也是乡村振兴的核心要素。基于文化自信视域,通过田野调查和文献法,探讨西江苗寨苗绣产业复兴实践。西江苗寨苗绣产业复兴经历了... 民族地区乡村振兴是实现中国式现代化的重要组成部分,而文化自信是民族地区乡村振兴的重要动力和有力保障,也是乡村振兴的核心要素。基于文化自信视域,通过田野调查和文献法,探讨西江苗寨苗绣产业复兴实践。西江苗寨苗绣产业复兴经历了从文化自省到文化自信的过程,其背后的逻辑与张力是民族传统文化资源的现代性创造、转化和资本化过程,是主体与价值、物质与精神、传统与创新的交融过程。面对物质与精神、传统与现代、地方与全球等多重张力与矛盾,西江苗寨苗绣产业实现了均衡性的重构,实现了乡村产业振兴的可持续发展,为民族地区乡村产业振兴提供了有益借鉴。 展开更多
关键词 文化自信 乡村振兴 西江苗寨 苗绣产业
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旅游驱动下传统民族村寨文化景观演化特征与机理研究——基于贵州西江苗寨的案例 被引量:3
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作者 朱正斌 李瑞 +1 位作者 殷红梅 于丹 《资源开发与市场》 CAS 2024年第1期152-160,共9页
文化景观是地域文化的重要表征形式,旅游发展不可避免地影响地域文化景观的演化。以大规模旅游活动为主导动因,运用实地调查和参与式制图法,对贵州西江苗寨文化景观演化特征与机理进行分析。结果表明:①西江苗寨物质文化景观整体演化强... 文化景观是地域文化的重要表征形式,旅游发展不可避免地影响地域文化景观的演化。以大规模旅游活动为主导动因,运用实地调查和参与式制图法,对贵州西江苗寨文化景观演化特征与机理进行分析。结果表明:①西江苗寨物质文化景观整体演化强度较高,呈现出聚落协调扩张、土地利用破碎化,民居景观服务化,服饰景观展演化特征。②非物质文化景观整体演化程度较低,呈现出饮食文化景观再地方化,制度文化景观外显化,语言文化景观稳固化,歌舞节庆文化景观他娱化特征。③西江苗寨文化景观演化是多元利益主体共同作用的结果。旅游者通过旅游凝视与主客互动引导村寨文化景观的演化,政府和旅游经营者通过权力调配和资本的介入对村寨文化景观的演化进行规训与筛选,村寨居民通过社区参与对村寨文化景观进行叙事与重构。 展开更多
关键词 旅游驱动 民族村寨 文化景观 演化 机制 西江苗寨
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长江和西江大型船闸通航运行关键技术研究与展望 被引量:2
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作者 齐俊麟 陈冬元 +3 位作者 吴澎 李中华 廖鹏 柳晨光 《水运工程》 2024年第1期137-143,共7页
保障长江和西江大型船闸通航枢纽的畅通、安全、高效意义重大。针对闸-船-航道三要素影响因素多、耦合性强,航道水流非定常,水位变幅高、变率快等难题,研究大型船闸通过能力多维分析建模与仿真、非恒定流下船闸航道水动力学特性分析、... 保障长江和西江大型船闸通航枢纽的畅通、安全、高效意义重大。针对闸-船-航道三要素影响因素多、耦合性强,航道水流非定常,水位变幅高、变率快等难题,研究大型船闸通过能力多维分析建模与仿真、非恒定流下船闸航道水动力学特性分析、多约束非定常船-闸水动力学精细化建模等方法,攻克了复杂多变条件下船闸中间航道通航、新标准船型与船闸协同下快速过闸、大型船闸扩能建设工程设计等船闸通过能力提升关键技术,以及大型船闸联动安全控制、关键设备运行智能监测、通航安全风险防控等联动运行安全控制关键技术,构建长江和西江大型船闸高效安全通航工程技术体系,并建立通航调度与安全一体化管控平台。从多尺度动力学、数字孪生、智能化与国产化和绿色生态技术等方面,展望大型船闸通航运行科技发展的方向。 展开更多
关键词 长江和西江 大型船闸 通过能力 通航调度
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珠江口盆地西江凹陷裂陷期构造转换及其对沉积的意义
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作者 李康 单玄龙 +3 位作者 郝国丽 热西提·亚力坤 徐川 沈梦蓉 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第4期1095-1109,共15页
珠江口盆地珠Ⅰ坳陷在早始新世—早渐新世的裂陷期主要经历了珠琼运动Ⅰ幕和Ⅱ幕,发育文昌组和恩平组。西江凹陷位于珠Ⅰ坳陷西部,凹陷内番禺4洼是已证实的富生烃洼陷,西江主洼和西江36洼勘探程度较低。为了进一步认识西江凹陷在裂陷期... 珠江口盆地珠Ⅰ坳陷在早始新世—早渐新世的裂陷期主要经历了珠琼运动Ⅰ幕和Ⅱ幕,发育文昌组和恩平组。西江凹陷位于珠Ⅰ坳陷西部,凹陷内番禺4洼是已证实的富生烃洼陷,西江主洼和西江36洼勘探程度较低。为了进一步认识西江凹陷在裂陷期的构造特征及其对沉积的控制,本文利用最新三维地震数据和解释成果,结合有限的钻井资料,对文昌期和恩平期的洼陷结构、断裂体系、沉降中心迁移规律及沉积体系分布等进行了系统分析。研究发现:西江凹陷在裂陷期发生了构造转换,主要体现在早文昌期、晚文昌期和恩平期的洼陷结构、断裂体系和控洼断层活动性的规律性变化以及沉降中心的迁移;沉积中心与沉降中心迁移基本一致,早、晚文昌期各洼陷发育半深湖—深湖亚相,沉积中心向西南迁移,恩平期沉积中心转向北部西江主洼一侧;裂陷期区域伸展应力方向的顺时针旋转,以及北西向先存断裂在文昌期的先后活化是构造转换的诱因,其控制了沉积体系的展布。分析西江凹陷的构造转换和沉积体系展布规律,对在珠Ⅰ坳陷深部寻找湖相烃源岩和富生烃洼陷具有一定意义。 展开更多
关键词 珠江口盆地 西江凹陷 珠琼运动 区域应力 构造转换 沉积体系
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西江伍氏华吸鳅仔、稚鱼的异速生长研究
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作者 文浩 徐林 +6 位作者 吴志强 黄亮亮 高明慧 宋琦亮 何佳洋 刘昊 孙扬言 《四川动物》 北大核心 2024年第2期146-153,共8页
运用光学显微镜和实验生态学的研究方法,对伍氏华吸鳅Sinogastromyzon wui仔、稚鱼从出膜到30日龄各器官的异速生长进行研究。结果表明,吻长、眼径、头长、头高、体高和体长均存在异速生长的现象(P<0.05),头部器官比身体其他器官优... 运用光学显微镜和实验生态学的研究方法,对伍氏华吸鳅Sinogastromyzon wui仔、稚鱼从出膜到30日龄各器官的异速生长进行研究。结果表明,吻长、眼径、头长、头高、体高和体长均存在异速生长的现象(P<0.05),头部器官比身体其他器官优先发育。吻长和眼径一直保持正异速生长,头长的生长拐点出现在12~13日龄,拐点前后均保持正异速生长,头高的生长拐点在7~8日龄,拐点前是负异速生长,拐点后是正异速生长;体高的拐点出现在15~16日龄,拐点前后均保持正异速生长,吻至肛长一直保持等速生长,体长保持等速生长。头部器官在早期发育阶段优先发育,可以增强捕食和躲避天敌的能力,并有助于为仔鱼期发育提供能量,适应外界环境,提高存活率。本研究可丰富伍氏华吸鳅仔、稚鱼发育过程的基础生物学资料,为育苗生产和野生早期资源的保护提供理论支撑。 展开更多
关键词 伍氏华吸鳅 异速生长 仔、稚鱼 生长拐点 西江
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珠江口盆地西江凹陷XJ-A构造古近系储层特征及对油气成藏的影响 被引量:1
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作者 冯进 马永坤 +4 位作者 贾培蒙 史玉玲 邱欣卫 牛胜利 梁浩然 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期392-402,共11页
西江凹陷位于珠江口盆地北部珠一坳陷西南部,与紧邻的惠州凹陷相比,其勘探程度相对较低,研究工作较为薄弱。近期的研究揭示,西江凹陷古近系恩平组和文昌组也具有足够的生排烃与勘探开发潜力。为了明确西江凹陷古近系储层条件对油气成藏... 西江凹陷位于珠江口盆地北部珠一坳陷西南部,与紧邻的惠州凹陷相比,其勘探程度相对较低,研究工作较为薄弱。近期的研究揭示,西江凹陷古近系恩平组和文昌组也具有足够的生排烃与勘探开发潜力。为了明确西江凹陷古近系储层条件对油气成藏的影响,本文选择位于西江主洼的XJ-A构造,利用储层物性、沉积相、薄片鉴定及包裹体测试资料等,对研究区的储层宏观条件和微观特征进行了详细的分析。研究结果表明XJ-A构造古近系沉积相以滨浅湖、中深湖和辫状河三角洲相为主,其中恩平组发育了大套以滨浅湖相为主的泥岩,文昌组则以辫状河三角洲相的砂岩为主,形成了“恩平富泥、文昌富砂”的特点;恩平组砂岩多为长石、石英类砂岩,而文昌组以长石类砂岩为主;恩平组砂岩孔隙度集中在5%~15%,而文昌组砂岩分布于10%~15%,它们的渗透率集中分布在(1~10)×10-3μm 2范围内,均属于低/特低孔、低渗储层;储层的成岩作用主要包括压实、自生矿物沉淀、溶蚀、交代和充填作用。结合该地区砂岩储层捕获的包裹体均一温度、有机质镜质体反射率和伊利石/蒙脱石混层中蒙脱石质量分数等,综合判断XJ-A构造的砂岩储层处于中成岩阶段的A 2期。综合分析表明,XJ-A构造古近系发育有良好的储层条件,同时古近系砂体也为油气运移提供了有效的横向运移通道,并且可以与研究区断裂相配合输导油气,为油气在斜坡带圈闭内聚集成藏提供保障。 展开更多
关键词 砂岩储层 成岩作用 油气成藏 古近系 西江凹陷
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基于CNN-LSTM-Attention和自回归的混合水位预测模型
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作者 吕海峰 涂井先 +1 位作者 林泓全 冀肖榆 《水利水电技术(中英文)》 北大核心 2024年第6期16-31,共16页
【目的】水位预测对交通运输、农业以及防洪措施具有重要影响。精确的水位值可用于提升水道运输的安全及效率、降低洪水风险,同时也是保障区域可持续发展的必要条件。【方法】提出一种CRANet的混合水位预测模型,以卷积神经网络(CNN)、... 【目的】水位预测对交通运输、农业以及防洪措施具有重要影响。精确的水位值可用于提升水道运输的安全及效率、降低洪水风险,同时也是保障区域可持续发展的必要条件。【方法】提出一种CRANet的混合水位预测模型,以卷积神经网络(CNN)、长短期记忆网络(LSTM)、注意力机制以及自回归(AR)组件为基础,旨在应对时间序列数据中存在的线性与非线性问题,缓解自回归及ARIMA模型的缺陷。其应用不仅在于为航运调度提供决策支撑,加强导航安全效率,同样能提升防洪减灾的能力。其中,CNN和LSTM组件有效地针对数据集内的局部和全局关系进行捕捉,AR组件则能充分考虑数据的时间序列特性。同时,通过注意力机制,模型能够优先考虑相关特性,提高预测效果。【结果】研究成果所提出的模型已成功应用于中国西江梧州站的水位预测,在测试集上预测未来3 h级别水位的MAE、RMSE和R^(2)分别为0.086、0.114 5和0.950 8。【结论】结果表明所提出的CRANet模型在水位预测方面的高可用性、准确度与稳健性,相较于AR、SVR、CNN、LSTM等模型具有更优的MAE、RMSE和R^(2)。 展开更多
关键词 时间序列 水位预测 CNN LSTM ATTENTION 影响因素 洪水 西江
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基于Copula函数的西江干流与粤西沿海诸小河径流丰枯遭遇分析
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作者 刘成 周秋红 +1 位作者 王占海 吴绍飞 《水电能源科学》 北大核心 2024年第9期11-16,共6页
环北部湾广东水资源配置工程从西江干流取水至广东省粤西地区,为从根本上缓解粤西地区缺水问题,研究西江干流与粤西沿海诸小河径流丰枯遭遇对工程水资源优化配置及运行调度具有重要意义。为此,基于西江干流控制水文站梧州站与粤西二个... 环北部湾广东水资源配置工程从西江干流取水至广东省粤西地区,为从根本上缓解粤西地区缺水问题,研究西江干流与粤西沿海诸小河径流丰枯遭遇对工程水资源优化配置及运行调度具有重要意义。为此,基于西江干流控制水文站梧州站与粤西二个小河控制站,即鉴江化州站及九洲江缸瓦窑站数据资料,采用Copula函数建立了年、枯期、汛期不同时间尺度的径流联合分布函数,分析了径流丰枯遭遇规律。结果表明,西江干流与粤西诸小河径流间具有较高的互补性,建设水资源配置工程可很好地缓解粤西地区的缺水问题。 展开更多
关键词 环北部湾 COPULA函数 西江 粤西沿海诸小河 丰枯遭遇
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