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Vulnerability assessment of coastal wetlands in Minjiang River Estuary based on cloud model under sea level rise
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作者 Xiaohe Lai Chuqing Zeng +4 位作者 Yan Su Shaoxiang Huang Jianping Jia Cheng Chen Jun Jiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期160-174,共15页
The change of coastal wetland vulnerability affects the ecological environment and the economic development of the estuary area.In the past,most of the assessment studies on the vulnerability of coastal ecosystems sta... The change of coastal wetland vulnerability affects the ecological environment and the economic development of the estuary area.In the past,most of the assessment studies on the vulnerability of coastal ecosystems stayed in static qualitative research,lacking predictability,and the qualitative and quantitative relationship was not objective enough.In this study,the“Source-Pathway-Receptor-Consequence”model and the Intergovernmental Panel on Climate Change vulnerability definition were used to analyze the main impact of sea level rise caused by climate change on coastal wetland ecosystem in Minjiang River Estuary.The results show that:(1)With the increase of time and carbon emission,the area of high vulnerability and the higher vulnerability increased continuously,and the area of low vulnerability and the lower vulnerability decreased.(2)The eastern and northeastern part of the Culu Island in the Minjiang River Estuary of Fujian Province and the eastern coastal wetland of Meihua Town in Changle District are areas with high vulnerability risk.The area of high vulnerability area of coastal wetland under high emission scenario is wider than that under low emission scenario.(3)Under different sea level rise scenarios,elevation has the greatest impact on the vulnerability of coastal wetlands,and slope has less impact.The impact of sea level rise caused by climate change on the coastal wetland ecosystem in the Minjiang River Estuary is mainly manifested in the sea level rise,which changes the habitat elevation and daily flooding time of coastal wetlands,and then affects the survival and distribution of coastal wetland ecosystems. 展开更多
关键词 vulnerability assessment cloud model coastal wetland minjiang river Estuary
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Research on Spatial Distribution of Settlements in the Upper Reaches of the Minjiang River
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作者 Lijun Song Shujun Tian +1 位作者 Lan Yang Na Fan 《Open Journal of Applied Sciences》 2023年第11期1967-1981,共15页
Under the background of the uplift of the Qinghai-Tibet Plateau, the settlements in the upper reaches of the Min River are significantly affected by the mountain environment, and their spatial distribution is typical ... Under the background of the uplift of the Qinghai-Tibet Plateau, the settlements in the upper reaches of the Min River are significantly affected by the mountain environment, and their spatial distribution is typical and representative. In this study, the relationship between settlements and topography, rivers and transportation, and the spatial distribution patterns of settlements, such as the aggregation and orientation characteristics of settlements, have been studied. The main conclusions include: 1) The settlement density decreases with the increase of elevation, slope, and distance from rivers and roads;76.25% and 63.17% of the settlements are distributed in the range of elevation 1500 - 3000 m and slope 6° - 25°, the upper reaches of the Min River are mostly alpine valley terrain, the bottom of the river has a low altitude, the landscape is undulating. The warm and humid climate is suitable for farming, conducive to agricultural production, and an ideal living environment for mountain residents. 2) The nuclear density of the settlement is distributed in strips along the axis of the river, and the closer to the river, the greater the nuclear density value. 3) Mathematical statistical methods were applied for the first time to realize the quantitative expression of the coupling of settlement and river direction. The influence of topographic conditions in different watersheds on the coupling degree of settlement extension and river flow direction was revealed. The slope of the fitted straight line between the settlement and river direction was 0.897, and the two directions were consistent. Except for the mainstream of the Min River, the larger values of the standard deviation ellipse flattening of settlements in each basin appeared in the upper reaches of the bay, and the overall trend showed a gradual decrease from the upstream to the downstream, which was consistent with the topographic change characteristics of the basin. 展开更多
关键词 Settlement Spatial Distribution AGGLOMERATION Alpine Valleys The Upper Reaches of the minjiang river
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Two Village Ecosystems in the Upper Minjiang River, China: A Comparison of Emergy Flow 被引量:6
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作者 Chen Yong, Chen Guojie, Wang QingInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China Institute of Environmental Science and Engineering, Sichuan University, Chengdu 610064, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期935-939,共5页
By using the concept of emergy and method of emergy analysis, this paper has studied two mountain settlement (village) ecosystems in two aspects: input and output of energy in the agro-systems and the use of fuel ener... By using the concept of emergy and method of emergy analysis, this paper has studied two mountain settlement (village) ecosystems in two aspects: input and output of energy in the agro-systems and the use of fuel energy. The result reveals that the settlement agro-system in the valley of Minjiang River is better in both structure and function than that at the so-called half-high mountain. The former one is higher than the latter one regarding such indices as emergy yield ratio, labor productivity of emergy and emergy sustainable index, but lower than the latter one regarding environmental loading ratio. In terms of fuel emergy, the settlement in the valley enjoys more diversified sources and is less depending on bio-energy while the settlement at the half-high mountain has only one source (i. e. fuel wood) , much depending on bio-energy, may exert a greater pressure on environment. 展开更多
关键词 Upper minjiang river settlement (village) ECOSYSTEM EMERGY
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Impacts of future climate change(2030-2059)on debris flow hazard:A case study in the Upper Minjiang River basin,China 被引量:4
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作者 LI Ming TIAN Cong-shan +3 位作者 WANG Yu-kuan LIU Qin LU Ya-feng WANG Shan 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1836-1850,共15页
An increase in extreme precipitation events due to future climate change will have a decisive influence on the formation of debris flows in earthquake-stricken areas. This paper aimed to describe the possible impacts ... An increase in extreme precipitation events due to future climate change will have a decisive influence on the formation of debris flows in earthquake-stricken areas. This paper aimed to describe the possible impacts of future climate change on debris flow hazards in the Upper Minjiang River basin in Northwest Sichuan of China, which was severely affected by the 2008 Wenchuan earthquake. The study area was divided into 1285 catchments, which were used as the basic assessment units for debris flow hazards. Based on the current understanding of the causes of debris flows, a binary logistic regression model was used to screen key factors based on local geologic, geomorphologic, soil,vegetation, and meteorological and climatic conditions. We used the weighted summation method to obtain a composite index for debris flow hazards, based on two weight allocation methods: Relative Degree Analysis and rough set theory. Our results showed that the assessment model using the rough set theory resulted in better accuracy. According to the bias corrected and downscaled daily climate model data, future annual precipitation(2030-2059) in the study area are expected to decrease, with an increasing number of heavy rainfall events. Under future climate change, areas with a high-level of debris flow hazard will be even more dangerous, and 5.9% more of the study area was categorized as having a high-level hazard. Future climate change will cause an increase in debris flow hazard levels for 128 catchments, accounting for 10.5% of the total area. In the coming few decades, attention should be paid not only to traditional areas with high-level of debris flow hazards, but also to those areas with an increased hazard level to improve their resilience to debris flow disasters. 展开更多
关键词 Debris flow Hazard assessment Relative degree analysis Rough set theory Future climate change minjiang river basin
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BIOGEOCHEMICAL BEHAVIOR OF NUTRIENTS AND THEIR FLUXES IN THE MINJIANG RIVER ESTUARY 被引量:1
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作者 陈水土 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第2期150-155,共6页
The biogeochemical behavior of DIN (dissolved inorganic nitrogen), phosphate and silicate in the Minjiang River estuary is discussed based on data obtained from May, 1990 to Feb., 1991 oceanographic surveys in the are... The biogeochemical behavior of DIN (dissolved inorganic nitrogen), phosphate and silicate in the Minjiang River estuary is discussed based on data obtained from May, 1990 to Feb., 1991 oceanographic surveys in the area. The annual fluxes of nutrients in the Minjiang River estuary were estimated to be 326.8 ×103 t for silicate, 771.0 t for phosphate, 45.7×103 t for DIN (42.1×103 t for nitrate, 3.0×103 t for ammonia. 600 t for nitrite), respectively. 展开更多
关键词 minjiang river ESTUARY BIOGEOCHEMICAL behavior FLUXES of NUTRIENTS
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Late Pleistocene environmental information on the Diexi paleo-dammed lake of the upper Minjiang River in the eastern margin of the Tibetan Plateau, China 被引量:1
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作者 WANG Lan-sheng WANG Xiao-qun +6 位作者 SHEN Jun-hui YIN Guan CUI Jie XU Xiang-ning ZHANG Zhi-long WAN Tao WEN Li-wang 《Journal of Mountain Science》 SCIE CSCD 2020年第5期1172-1187,共16页
In 1999, Diexi paleo-dammed lake(2349 m a.s.l.) was discovered around Diexi town along the Minjiang River in Sichuan province. Diexi is located where the eastern edge of the Tibetan Plateau and the Sichuan Basin meet.... In 1999, Diexi paleo-dammed lake(2349 m a.s.l.) was discovered around Diexi town along the Minjiang River in Sichuan province. Diexi is located where the eastern edge of the Tibetan Plateau and the Sichuan Basin meet. The dammed lake was formed during the Last Glacial Maximum of the Late Pleistocene(~30,000 years ago) and began to empty about 15,000 years ago. The lacustrine sediments(up to 240 m thick) preserve abundant paleoenvironment information. In this paper, a mass of oxygen isotopes and 14 C dating from drilled cores are analyzed and discussed. The δ18 O curve on the paleo climate from this section is comparable with the coeval paleo climatic curves of ice cores and karsts in China and others. Furthermore, the physical model testing has confirmed that the disturbed zones in the core are caused by strong earthquakes occurred at least 10 times, which implies strong crustal deformation, as an important driving force, affecting climate change. This study provides a new window to observe East Asian monsoon formation, paleoenvironmental evolution and the global climate change. 展开更多
关键词 Late Pleistocene Paleo-dammed lake Paleo climate EARTHQUAKE minjiang river Diexi
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A Landscape Pattern Analysis Method Based on Boundaries and Nodes:A Case Study in Upper Minjiang River,China 被引量:3
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作者 WEN Qingchun LI Xiuzhen +5 位作者 HE Hongshi HU Yuanman CHEN Xin CHANG Yu WANG Wei BU Rencang 《Chinese Geographical Science》 SCIE CSCD 2014年第1期50-59,共10页
Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until recently.This s... Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until recently.This study investigated the possibility of applying boundary-and node-based methods in landscape pattern analysis to the upper reaches of the Minjiang River in the southwestern China.Boundary-based and node-based landscape indices were selected to be used in analyzing changes in landscape patterns,and the results were compared with analysis using traditional pattern indices.We compared the responses of patch-area-based,boundary-length-based and node-number-based indices,and concluded that boundary-based and node-based indices are more sensitive to disturbance than patch-based indices with various patterns,and node-based indices are even more sensitive than boundary-based ones.Thus,the results suggest that boundary-based and node-based pattern analysis methods provide helpful supplementary information to traditional patch-based pattern analysis methods.The results about pattern dynamics of landscapes in the upper reaches of the Minjiang River based on boundaries and nodes showed that with human disturbance,the dominance of forest landscape was weakened by other landscape types;thus the landscape pattern of the study area became more homogeneous and the boundary network became more complex.These changes further augmented disturbance interfaces in the landscape and increased the possibilities of further landscape fragmentation. 展开更多
关键词 景观格局分析 岷江上游 节点数 中国西南 边界 景观生态学 景观破碎化 景观尺度
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RELATIONSHIP BETWEEN MINJIANG RIVER ESTUARY TRACE METALS AND NUTRIENTS
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作者 邹栋梁 高淑英 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1996年第3期261-265,共5页
This study on the relationships between dissolved Cd, Cu, Pb and nutrients in the Minjiang River Estuaryduring high and low discharges (in June and Oct., 1990) showed that during both high and lowdischarges Cd, Cu and... This study on the relationships between dissolved Cd, Cu, Pb and nutrients in the Minjiang River Estuaryduring high and low discharges (in June and Oct., 1990) showed that during both high and lowdischarges Cd, Cu and Pb exhibited additive, conservative and removal behaviour, respectively. Cd increaseappeared to be primarily related to Cd regeneration from microplankton and its organic remains. while Pbremoval was dominated by abiotic processes. 展开更多
关键词 TRACE metal NUTRIENT RELATIONSHIP minjiang river ESTUARY
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A PREDICTION ABOUT THE EFFECT OF THE BUILDING OF SHUIKOU HYDROPOWER STATION ON THE ECOLOGICAL ENVIRONMENT OF THE MIDDLE-LOWER REACHES OF THE MINJIANG RIVER
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作者 余泽忠 《Chinese Geographical Science》 SCIE CSCD 1991年第3期54-67,共14页
The building of Shuikou Hydropower Station in the Minjiang River is the largest one in the region of east China. Its install capacity is 1.4 million kw., and its generated energy of planning is 4.95 billion kwh each y... The building of Shuikou Hydropower Station in the Minjiang River is the largest one in the region of east China. Its install capacity is 1.4 million kw., and its generated energy of planning is 4.95 billion kwh each year. In accordance with a comprehensive survey of the valley of the middle-lower reaches of the Minjiang River and the characteristic of hydrography and in association with the specific type of the hydrography station, we can be sure that no harm will be done to the ecological environment when a hydropower station is built at Shuikou. Not only the deposition of silt within the reservoir must not be very serious, it is also more favorable than before for the irrigation of farmland on plains in the lower reaches of the Minjiang River and inland navigation.In addition, after the completion of the power station, the ecological environment will be the same as before both at the Minjiang River estuary and beyond it. 展开更多
关键词 Shuikou HYDROPOWER Station middle-lower reaches of the minjiang river ecological environment IRRIGATION of farmland.
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Seasonal and spatial variations in rare earth elements and yttrium of dissolved load in the middle,lower reaches and estuary of the Minjiang River,southeastern China 被引量:1
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作者 朱旭旭 高爱国 +5 位作者 林建杰 简星 杨玉峰 张延颇 侯昱廷 龚松柏 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期700-716,共17页
A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower... A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower reaches and estuary of the Minjiang River, southeastern China. The results display that the REE abundances in Minjiang River, ranging from 3.3–785.9 ng/L, were higher than those of many of the major global rivers. The total REE concentrations(∑REE) were seasonally variable, averaging in 5 937.30, 863.79, 825.65 and 1 065.75 ng/L during second highest flow(SHF), normal flow(NF), low flow(LF) and high flow(HF) season, respectively. The R_(( L/M)) and R_((H/M)) ratios reveal the spatial and temporal variations of REE patterns, and particularly vary apparently in the maximum turbidity zone and estuary. REE patterns of dissolved loads are characterized by progressing weaker LREEs-enrichment and stronger HREEsenrichment downstream from middle reaches to estuary during all four seasons. Comparing with NF and LF seasons, in which REE patterns are relatively flat, samples of SHF season have more LREE-enriched and HREE-depleted patterns that close to parent rocks, while samples of HF season are more LREEs-depleted and HREE-enriched. REE fractionations from the middle to lower reaches are stronger in the SHF and HF seasons than those in NF and LF seasons. Generally, spatial and seasonal variations in REE abundance and pattern are presumably due to several factors, such as chemical weathering, mixture with rainfall and groundwater, estuarine mixing, runoff, biological production and mountain river characters, such as strong hydrodynamic forces and steep slopes. The highest Gd/Gd* always occurs at north ports during all four seasons, where most of the large hospitals are located. This suggests Gd anomalies are depended on the density of modern medical facilities. Y/Ho ratios fl uctuate and positively correlate to salinity in estuary, probably because of the geochemical behavior differences between Y and Ho. 展开更多
关键词 稀土元素 浓度 生态环境 湖泊
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GIS-Based Spatial Analysis and Modeling for Landslide Hazard Assessment:A Case Study in Upper Minjiang River Basin
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作者 FENG Wenlan ZHOU Qigang +4 位作者 ZHANG Baolei ZHOU Wancun LI Ainong ZHANG Haizhen XIAN Wei 《Wuhan University Journal of Natural Sciences》 CAS 2006年第4期847-852,共6页
By analyzing the topographic features of past landslides since 1980s and the main land-cover types (including change information) in landslide-prone area, modeled spatial distribution of landslide hazard in upper Mi... By analyzing the topographic features of past landslides since 1980s and the main land-cover types (including change information) in landslide-prone area, modeled spatial distribution of landslide hazard in upper Minjiang River Basin was studied based on spatial analysis of GIS in this paper. Results of GIS analysis showed that landslide occurrence in this region closely related to topographic feature. Most areas with high hazard probability were deep-sheared gorge. Most of them in investigation occurred assembly in areas with elevation lower than 3 000 m, due to fragile topographic conditions and intensive human disturbances. Land-cover type, including its change information, was likely an important environmental factor to trigger landslide. Destroy of vegetation driven by increase of population and its demands augmented the probability of landslide in steep slope. 展开更多
关键词 LANDSLIDE PROBABILITY spatial modeling upper minjiang river
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Unsteadiness of COD in the Upper and Middle Reaches of Minjiang River
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作者 Liu Zuhan Zhang Bin +2 位作者 Wang Lili Qin Fachao Liu Lijun 《Chinese Journal of Population,Resources and Environment》 2010年第4期65-68,共4页
This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by th... This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by the Water Quality Monitoring Station,Minjiang River Bridge,Leshan City,Sichuan Province.The results of the wavelet analysis indicate that the COD index oscillates alternatively and differently at each time-scale in an oneyear cycle,and the density of COD,subjected to the runoff volume,the effects of Wenchuan Earthquake and agricultural seeding and industrial construction,etc.,is high in winter and spring,mild in summer and autumn. 展开更多
关键词 wavelet analysis COD the upper and middle reaches of the minjiang river
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Risk Assessment of Highway in the Upper Reaches of Minjiang River under the Stress of Debris Flow
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作者 Mingyang Li Shujun Tian +2 位作者 Chen Huang Wenqia Wu Shiwu Xin 《Journal of Geoscience and Environment Protection》 2021年第7期21-34,共14页
The southwest mountainous area is a frequent debris flow disaster area in<span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Chin... The southwest mountainous area is a frequent debris flow disaster area in<span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> China, which poses a serious threat to the regional roads and greatly affects the normal traffic operation and the safety of residents’ lives and property. The debris flow risk assessment of highway can quantify the threat degree of debris flow to the roads. In this paper, from the perspective of villages and towns, taking the upper reaches of Minjiang River as the research area, four factors including road network density, highway disaster resistance capacity, population density and highway cost are selected, and the weight is obtained by using entropy weight method, and the debris flow vulnerability evaluation results of highway are obtained by weighted calculation. Four indexes of debris flow density, shape factor, relative height difference and annual rainfall are selected to evaluate the debris flow hazard of highway by using the information method. Based on the vulnerability and hazard evaluation results, the ri</span><span style="font-family:Verdana;">sk of highway debris flow is evaluated, and the results are classified and</span><span style="font-family:Verdana;"> discussed. The results show that: the risk of debris flow on the upper reaches of Minjiang River is relatively low, the overall spatial distribution shows a trend of high in the East and low in the west, and the overall risk of township roads in Wenchuan county is the highest;The risk of debris flow is generally high within </span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">-10 to 30</span><span style="font-family:Verdana;"> km from the central fault zone of Longmenshan.</span></span></span></span> 展开更多
关键词 The Upper Reaches of minjiang river Risk Assessment HIGHWAY Debris Flow
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Based on the Theory of Optimizing the Allocation of Research of Sustainable Utilization of Water Resources of the Upper Reaches of Minjiang River
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作者 Canyuan Liu 《Natural Resources》 2020年第10期473-498,共26页
<span style="font-family:""><span style="font-family:Verdana;">Water resource is an important supporting material for life support system and eco</span><span style="f... <span style="font-family:""><span style="font-family:Verdana;">Water resource is an important supporting material for life support system and eco</span><span style="font-family:Verdana;">nomic development, and the sustainable development and utilization of water resource </span></span><span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> the guarantee of social sustainable development. The upper Minjiang River is the most important source of water supply for the Chengdu Plain. With the water resources of the upper Minjiang River facing the problems of overall water volume reduction, flood and water pollution, etc.</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> based on the optimal allocation theory, this paper constructs an optimal allocation model of water resourc</span><span style="font-family:Verdana;">es in the upper reaches of the Minjiang River, analyzes its characteristics and proposes some relevant countermeasures and suggestions to solve the existing problems, aiming to provide reference</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> for the sustainable utilization of water resources in the upper reaches of the Minjiang River. 展开更多
关键词 The Upper Reaches of minjiang river Water Resources Optimized Configuration
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闽江流域多时间尺度降雨—径流关系变化与成因 被引量:1
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作者 耿凯利 陈兴伟 +3 位作者 郑美玲 谷梓鹏 陈莹 刘梅冰 《中国水土保持科学》 CSCD 北大核心 2024年第1期35-41,共7页
为进一步揭示闽江流域降雨—径流关系的时空变化规律,识别主要驱动因子,基于1960—2019年降雨和径流数据,应用TFPW—MK方法,按照年以及年内的汛期与非汛期、前汛期和后汛期、最大月和最小月等不同时间尺度,检测闽江上游三大支流、干流... 为进一步揭示闽江流域降雨—径流关系的时空变化规律,识别主要驱动因子,基于1960—2019年降雨和径流数据,应用TFPW—MK方法,按照年以及年内的汛期与非汛期、前汛期和后汛期、最大月和最小月等不同时间尺度,检测闽江上游三大支流、干流及全流域等空间尺度的降雨—径流演变趋势;结合Sen trend方法,从气候变化、土地利用和水库工程建设3方面,分析影响降雨—径流关系变化的成因。结果表明:1)闽江流域及各支流年降雨—径流均呈不显著上升,趋势变化一致;2)除支流建溪流域,闽江及其他支流非汛期降雨—径流上升趋势显著;汛期内部趋势变化分化明显,前汛期降雨—径流略减少,后汛期降雨—径流大部分显著增加;3)极端降雨—径流的变化趋势不一致,主要受大型水库工程建设的影响。基于多时间尺度的分析,更深入揭示闽江流域降水、径流的演变及气候变化与人类活动的影响,对区域水资源管理与水土保持具有重要参考价值。 展开更多
关键词 降雨—径流关系 多时间尺度 水库工程 闽江流域
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2000—2020年岷江上游干旱河谷区植被时空变化及其地形效应
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作者 周雪妮 肖成志 +4 位作者 刘磊 计扬 曹亚廷 李小红 巴仁基 《现代地质》 CAS CSCD 北大核心 2024年第3期589-598,共10页
针对岷江上游干旱河谷区生态极其脆弱的特点,利用NDVI数据通过像元二分法反演了岷江上游干旱河谷区2000—2020年的植被覆盖度(FVC),运用线性趋势分析和F显著性检验法,定量分析了FVC的时空变化规律,结合地形数据剖析岷江上游干旱河谷区FV... 针对岷江上游干旱河谷区生态极其脆弱的特点,利用NDVI数据通过像元二分法反演了岷江上游干旱河谷区2000—2020年的植被覆盖度(FVC),运用线性趋势分析和F显著性检验法,定量分析了FVC的时空变化规律,结合地形数据剖析岷江上游干旱河谷区FVC趋势变化与海拔、坡度、坡向之间的关系。结果表明:(1)2000—2020年,研究区植被覆盖度呈波动增加趋势,年均FVC由2000年0.62增加至2020年的0.67。(2)在空间上,植被覆盖度由低海拔至高海拔呈现增高趋势,低等级和中低等级植被覆盖度主要分布在岷江干流及岷江支流杂谷脑河两岸,中等级和中高等级植被覆盖度集中分布在河谷两岸低中山和中山区,高等级植被覆盖度则主要分布在远离河谷的高中山和中高山区。(3)高等级植被覆盖面积随海拔增加呈先减小后增加的趋势,在1100~1400 m和3200~3500 m区域达到峰值;高等级植被覆盖度面积随坡度增加呈现先增加后减少的趋势,10°~20°和30°~40°是植被覆盖度高等级和中高-高等级的峰值区;总体上阳坡植被覆盖度高于阴坡。植被覆盖状况受海拔、坡度以及坡向影响较大,对岷江上游干旱河谷区生态保护应考虑地形影响,因地制宜采取措施。 展开更多
关键词 植被覆盖度 时空变化 地形效应 岷江上游 干旱河谷
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气候和土地利用变化情景下闽江流域水沙变化模拟
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作者 余文广 陈芸芝 +1 位作者 唐丽芳 汪小钦 《水土保持学报》 CSCD 北大核心 2024年第2期216-233,245,共19页
[目的]模拟未来土地利用和气候影响下的流域水沙变化有利于制定适合的流域管理计划。[方法]基于土地利用和气象数据,结合CMIP6气候模式数据、PLUS模型和SWAT模型,定量模拟2030年土地利用及不同气候情景下径流和泥沙的时空变化。[结果](1... [目的]模拟未来土地利用和气候影响下的流域水沙变化有利于制定适合的流域管理计划。[方法]基于土地利用和气象数据,结合CMIP6气候模式数据、PLUS模型和SWAT模型,定量模拟2030年土地利用及不同气候情景下径流和泥沙的时空变化。[结果](1)SWAT模型在闽江流域月尺度模拟精度较好,其中径流模拟的R 2范围为0.80~0.95,NSE范围为0.75~0.91;泥沙模拟的R 2范围为0.75~0.98,NSE范围为0.64~0.94。(2)利用2020年土地利用数据对PLUS模型进行精度评估的Kappa系数为0.77,模拟2030年闽江流域建设用地和耕地将分别增加325.64,1157.51 km^(2)。(3)SSP2-4.5和SSP5-8.5情景下,2025-2035年平均降水量分别增加0.15%和2.18%,年平均气温分别增加0.23,0.62℃。(4)低碳情景和高碳情景下,仅土地利用变化导致年平均径流量相较于基准期分别增加0.08%和0.07%,年平均输沙量分别增加0.24%和减少0.05%;仅气候变化导致年平均径流量相较基准期分别减少4.76%和4.11%,年平均输沙量分别增加18.12%和0.13%;土地利用和气候综合影响导致年平均径流量相较于基准期分别减少4.57%和3.93%,年平均输沙量分别增加18.28%和0.33%。(5)未来气候和土地利用综合变化情景下,地表径流和产沙量较高且增幅较大的区域集中在以南平邵武市为中心的流域西北部和以三明将乐县为中心的流域西南部。[结论]研究结果为未来闽江流域的合理开发建设提供一定参考依据。 展开更多
关键词 闽江流域 气候情景 土地利用变化 径流 输沙量 模拟
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闽江河口湿地围垦稻田对土壤铁碳结合特征的影响
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作者 刘旭阳 王纯 +7 位作者 郭萍萍 方云英 沈李东 胡世文 黑杰 王亚非 胥佳忆 王维奇 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2024年第1期44-54,共11页
土壤铁氧化物结合态有机碳是有机碳长期维持的主要途径,但其机理研究仍较为薄弱。为探究河口湿地围垦稻田对土壤铁碳结合特征的影响,本研究选择福建省闽江河口天然芦苇湿地与围垦稻田为研究对象,对两种类型土壤中的铁结合态有机碳(Fe-OC... 土壤铁氧化物结合态有机碳是有机碳长期维持的主要途径,但其机理研究仍较为薄弱。为探究河口湿地围垦稻田对土壤铁碳结合特征的影响,本研究选择福建省闽江河口天然芦苇湿地与围垦稻田为研究对象,对两种类型土壤中的铁结合态有机碳(Fe-OC)及其相关指标进行测定与分析。结果显示:①芦苇湿地围垦稻田改变了土壤氧化还原过程,显著影响土壤中铁相的转化。围垦后土壤二价铁[Fe(Ⅱ)]、三价铁[Fe(Ⅲ)]、活性总铁含量(HCl-Fe_(t))及Fe(Ⅲ)/Fe(Ⅱ)分别显著下降了24.68%、52.56%、51.45%、35.68%(P<0.05)。游离态氧化铁(Fe_(d))与无定形态铁(Fe_(o))含量分别显著下降了21.64%和29.24%(P<0.05),络合态铁(Fe_(p))含量则有所增加。②芦苇湿地围垦稻田显著影响土壤碳固存,Fe-OC与土壤有机碳含量(SOC)在围垦稻田后分别显著下降了39.03%和18.42%(P<0.05);芦苇湿地与稻田土壤Fe-OC均主要以吸附途径结合,稻田土壤Fe-OC对土壤有机碳的贡献率(fFe-OC)显著高于芦苇湿地(P<0.05)。③土壤全氮、含水量、电导率、铁以及土壤有机碳、溶解性有机碳与Fe-OC呈显著正相关(P<0.01)。本研究可为退耕还湿、土壤碳增汇提供科学参考。 展开更多
关键词 铁结合态有机碳 芦苇湿地 稻田 闽江河口
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岷江上游1995—2020年生态地质环境安全评价与时空演化分析
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作者 计扬 巴仁基 +3 位作者 肖成志 刘磊 周雪妮 曹亚廷 《现代地质》 CAS CSCD 北大核心 2024年第3期648-659,共12页
岷江上游是长江上游生态安全的重要屏障,在“5·12”汶川地震发生后,地下岩体、地表基质和地上生态都受到了严重的破坏。为探索岷江上游流域地震前后生态地质环境安全状况,从“地质环境-生态环境”两个维度选取了16个评价指标,基于A... 岷江上游是长江上游生态安全的重要屏障,在“5·12”汶川地震发生后,地下岩体、地表基质和地上生态都受到了严重的破坏。为探索岷江上游流域地震前后生态地质环境安全状况,从“地质环境-生态环境”两个维度选取了16个评价指标,基于AHP-PCA熵组合权重法对岷江上游流域1995年、2001年、2009年和2020年生态地质环境安全进行评价并分析演化趋势。结果表明:岷江上游流域生态地质环境安全整体以较安全-安全为主。其中,生态地质环境较安全-安全主要分布在流域的中、东部地区,较不安全-不安全主要分布在西、北部高山区以及深切河谷区,整体呈现中东部高、西部和北部低的格局。1995—2020年岷江上游生态地质环境安全整体呈现先降低后逐步升高的趋势。其中,流域北部及深切河谷区生态地质环境安全变化波动大,且呈现升高-降低-升高的趋势,生态地质环境不稳定;西南部生态地质环境安全整体以降低为主,虽降低区域逐渐减少,但总体生态地质环境仍持续变差;流域中部生态地质环境安全整体以升高为主,且升高区域逐渐增加,生态地质环境持续向好。本次研究结果可为岷江上游生态保护修复提供基础支撑。 展开更多
关键词 生态地质环境安全评价 层次分析法 主成分分析法 最小信息熵 岷江上游流域
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闽江下游水文情势演变及其对压咸流量保证率的影响
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作者 明昊文 张丹蓉 +1 位作者 管仪庆 王子元 《水电能源科学》 北大核心 2024年第3期1-5,共5页
针对近年来闽江下游河口自然水文情势发生变化致使咸潮上溯现象逐渐加剧的问题,选取闽江下游竹岐站1950~2018年逐日流量资料,采用Mann-Kendall法进行趋势和突变检验,确定1997年为径流突变年份。采用水文指标变化范围法(IHA/RVA)对突变... 针对近年来闽江下游河口自然水文情势发生变化致使咸潮上溯现象逐渐加剧的问题,选取闽江下游竹岐站1950~2018年逐日流量资料,采用Mann-Kendall法进行趋势和突变检验,确定1997年为径流突变年份。采用水文指标变化范围法(IHA/RVA)对突变前后两个时间序列1950~1996、1997~2018年的32个水文指标进行分析。结果发现除了低流量脉冲发生次数及历时和逆转次数为高度改变,其余指标均为中、低度改变,闽江下游水文整体改变度为38.16%,为中度改变。采用两种压咸流量方案对两个时间序列代表年进行保证率分析,其中方案1压咸流量过程的最小值及总需水量较方案2少,压咸流量保证率高。压咸流量保证率突变后较突变前整体增加,尤其是在枯水年,压咸流量保证率大幅增加,但同时存在丰水年压咸流量保证率下降的问题。说明水库的投入运行影响下游径流过程,可以改善枯水期下游河口地区咸潮入侵问题,但也使丰平枯各年的压咸流量保证率趋于一致。 展开更多
关键词 闽江下游 水文情势 IHA/RVA法 水文改变度 压咸流量 保证率
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