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Numerical simulation of groundwater and early warnings from the simulated dynamic evolution trend in the plain area of Shenyang,Liaoning Province(P.R. China) 被引量:2
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作者 LIU Jun-qiu XIE Xin-min 《Journal of Groundwater Science and Engineering》 2016年第4期367-376,共10页
Groundwater level is the most direct factor reflecting whether groundwater is in a virtuous cycle. It is the most important benchmark for deciding whether a balance can be struck between groundwater discharge and rech... Groundwater level is the most direct factor reflecting whether groundwater is in a virtuous cycle. It is the most important benchmark for deciding whether a balance can be struck between groundwater discharge and recharge and whether groundwater exploitation will trigger problems pertinent to environment, ecology and environmental geology. According to the borehole and long-term monitoring wells data in the plain area of Shenyang, a numerical groundwater model is established and used to identify and verify the hydrogeological parameters and balanced items of groundwater. Then the concept of red line levels, the control levels of groundwater is proposed, the dynamic evolution trend of groundwater under different scenarios is analyzed and predicted and groundwater alerts are given when groundwater tables are not between the lower limit and the upper limit. Results indicated:(1) The results of identification and verification period fitted well, and the calculation accuracy of balanced items was high;(2) with the implementation of shutting wells, groundwater levels in urban areas of Shenyang would exceed the upper limit water level after 2020 and incur some secondary disasters;(3) under the recommended scenario of water resources allocation, early-warnings for groundwater tables outside the range would occur in the year of 2020, 2023, 2025 respectively for successive wet, normal and dry years. It was imperative to reopen some groundwater sources and enhance real-time supervision and early-warning to prevent the occurrence of potential problems. 展开更多
关键词 Groundwater table Groundwater exploitation Numerical modeling of groundwater plain area of Shenyang
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Terrestrial water storage variation in Hebei plain area of China,based on ground surface gravimetry 被引量:1
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作者 Hongtao Hao Hongliang Liu +3 位作者 Xinlin Zhang Jin Wei Bin Zhao Minzhang Hu 《Geodesy and Geodynamics》 CSCD 2021年第3期190-196,共7页
Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Resu... Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Results show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land subsidence.With the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic data.These results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water. 展开更多
关键词 Hebei plain area Gravity variation Terrestrial water storage variation Ground surface gravimetry Land subsidence
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Assessment of Groundwater Source of Piedmont Plain Area of China Northwest Arid Region Based On Numerical Modeling 被引量:1
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作者 HOU Xianhua ZHANG Jiahao LIU Jilai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期419-420,共2页
After the middle of 1960s,along with the appearance and extensive utilization of computer featured in large capacity and rapid speed,numerical method(mainly include finite difference method and finite
关键词 GROUNDWATER source NUMERICAL simulation PIEDMONT plain area Xiangride-Ruomuhong Qaidam BASIN
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Eco-environment contribution of agroforestry to agriculture development in the plain area of China—Huai'an Prefecture, Jiangsu Province as the case study area
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作者 RENHong-chang LUYong-long +2 位作者 LIUCan MENGQing-hua SHIYa-juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期327-331,共5页
For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the app... For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the approaches were based on fixed-point data, and few was considered on the non-efficient factors and temporal scale effects. This paper studies the positive and negative benefits at a large temporal scale, and the effects of plain afforestation on stockbreeding and rural economy. The benefits of plain afforestation, correlation coefficiency of agroforestry and production factors are analyzed via stochastic frontier modeling in Huanghuaihai Plain Area of China; elastic coefficient of agroforestry, husbandry, farming, and total output of agricultural sector are calculated through adopting partial differential equation. Some conclusions can be drawn that, plain forests have an important effect on the development of plain agriculture. But shelterbelts and small-scale forests have different effect on the development of agricultural economy. Shelterbelts have negative effect on the industries, but small-scale forest has positive effect. On the whole, contribution of forest resource to value of animal husbandry and gross production value of agriculture is positive, and to the value of farming is negative. 展开更多
关键词 平原造林 农业发展 中国 生态建设
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Hydrocarbon Accumulation Process in the Marine Strata in Jianghan Plain Area, Middle China
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作者 XU Guosheng ZHANG Lijun +4 位作者 GONG Deyu WANG Guozhi YUAN Haifeng LI Changhong HU Xiaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第3期878-893,共16页
Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z–∈2, ∈2–O, S, D–C, P and T... Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z–∈2, ∈2–O, S, D–C, P and T1, can be identified with each epoch. The geology, stratigraphy, drilling, oil testing and other basic data as well as the measured inclusion and strontium isotope data in the study area are used in the analysis of the formation and evolution process of marine petroliferous reservoirs in the Jianghan Plain area. This study aims to provide a scientific basis for the further exploration of hydrocarbons in the Jianghan Plain and reduce the risks by analyzing the key factors for hydrocarbon accumulation in the marine strata. Our findings show that in the Lower Palaeozoic hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the early period of the Early Yanshanian, and the hydrocarbon reservoir was destroyed in the middle–late period of the Early Yanshanian. In the Lower Triassic–Carboniferous hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the Early Yanshanian, and the hydrocarbon reservoir suffered destruction from the Late Yanshanian to the Early Himalayanian. The preservation conditions of the marine strata in the Jianghan Plain area have been improved since the Late Himalayanian. However, because all source beds have missed the oil/gas generation fastigium and lost the capacity to generate secondary hydrocarbon, no reaccumulation of hydrocarbons can be detected in the study area's marine strata. No industrially exploitable oil/gas reservoir has been discovered in the marine strata of Jianghan Plain area since exploration began in 1958. This study confirms that petroliferous reservoirs in the marine strata have been completely destroyed, and that poor preservation conditions are the primary factor leading to unsuccessful hydrocarbon exploration. It is safely concluded that hydrocarbon exploration in the marine strata of the study area is quite risky. 展开更多
关键词 油气成藏过程 海相地层 江汉平原 平原地区 地层油气藏 天然气运移 中东 中国
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Spacial organization on the rural settlements in plain areas—taking Pinghu city in Zhejiang of China as an example
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作者 XUE Dong-qian1, YAO Shi-mou2, ZHANG Hong1 (1. Dept. of Tourism and Environment, Shaanxi Normal University, Xi’an 710062, China 2. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第3期59-64,共2页
This paper analyses the spacial distribution, quantity-scale, function-structure and facilities from the angle of spacial organizational optimizing theory and sustainable development thought. The authors point out the... This paper analyses the spacial distribution, quantity-scale, function-structure and facilities from the angle of spacial organizational optimizing theory and sustainable development thought. The authors point out the distributional principles of rural settlements in plain areas, and put forward planning and distribution of various levels of rural settlements (central villages, basic villages and natural villages). 展开更多
关键词 plain area CENTRAL VILLAGES basic VILLAGES natural VILLAGES spacial ORGANIZATION
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Study on Farmers' Cognition and Willingness to Plant Trees during Collective Forest Right Reform Based on Data from Plain Areas of Henan Province
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作者 Min LIU Shaozhou ZHOU 《Asian Agricultural Research》 2013年第6期14-18,23,共6页
On the basis of the survey data from plain areas of Henan Province,farmers' cognition and willingness to plant trees in collective forest right reform are studied. According to statistical analysis and regression ... On the basis of the survey data from plain areas of Henan Province,farmers' cognition and willingness to plant trees in collective forest right reform are studied. According to statistical analysis and regression equation of binary logistic regress analysis,it is generally believed that different participants have various attitudes to the reform,with regard to if planting trees or more,reform variables have a distinct effect,as well as income variable and loaning or lending variable. At last,some advices are put forward,that is,the government should strengthen collective forest right reform,accelerate matching reform and increase policy and financial support to forestry farmers. 展开更多
关键词 COLLECTIVE forest right system plain areas PERFORM
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Analysis on Change Tendency of the Precipitation Resource during Growth Period of the Conventional Crops in Plain Area before Taihang Mountains
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作者 Suqing Han Shijing Jia 《Meteorological and Environmental Research》 CAS 2013年第2期49-52,共4页
[Objective]The aim was to study change tendency of the precipitation resource during growth period of the conventional crops in plain area before Taihang Mountains. [Method]Based on daily precipitation data at Shijiaz... [Objective]The aim was to study change tendency of the precipitation resource during growth period of the conventional crops in plain area before Taihang Mountains. [Method]Based on daily precipitation data at Shijiazhuang meteorological station in recent 51 years,average rainfall during growth periods of the 9 kinds of conventional crops was obtained. Precipitation tendency during growth periods of the 9 kinds of conventional crops in plain area before Taihang Mountains was analyzed by Mann-Kendall nonparametric test. [Result]Seen from rainfall during growth periods of the different crops,rainfall was the least during the growth period of winter wheat,followed by summer corn. Rainfall during growth periods of the cotton,oil plant,vegetable,fruit tree,potato,rice and legumes was more. Under different guaranteed rates,precipitation change also had difference. Rainfall change during growth periods of the wheat and corn was bigger,and rainfall change during growth period of the rice was smaller. Change degree of the precipitation during growth periods of the cotton,oil plant,vegetable,fruit tree and legumes was equivalent,while precipitation change during growth period of the potato was the biggest. Seen from change tendency of the precipitation during growth periods of the different crops,precipitation in the growth period of winter wheat was increasing at a speed of 0. 62 mm /a. However,precipitation in growth periods of the other crops had a decreasing tendency. Precipitation in the growth periods of summer corn and legumes decreased at the same speed which was 2. 11 mm /a,while precipitation in growth periods of the cotton,oil plant,vegetable,fruit tree,potato and rice decreased insignificantly. [Conclusion] The study laid foundation for determination of the agricultural irrigation water and provided theoretical reference for regional agricultural water-saving. 展开更多
关键词 作物生育期 降水资源 平原地区 太行山 传统 作物生长期 平均降雨量 降水变化趋势
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Restudy of the storage and migration model of the Quaternary groundwater in Beijing Plain area 被引量:7
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作者 LIU YuanZhang WU Qiang +3 位作者 LIN Pei LIU JiuRong XING LiTing GAO ZhiHui 《Science China Earth Sciences》 SCIE EI CAS 2012年第7期1147-1158,共12页
Through a wide-spread groundwater sampling mainly at nested monitoring wells in the Beijing Plain area,combined with data collection,the study analyzes water level,hydrochemistry,temperature,tritium,deuterium,18O,14C ... Through a wide-spread groundwater sampling mainly at nested monitoring wells in the Beijing Plain area,combined with data collection,the study analyzes water level,hydrochemistry,temperature,tritium,deuterium,18O,14C and other aspects,and indicates that there exits an obvious stratification phenomenon of the groundwater in the alluvial plain area down in the middle part of alluvial-pluvial fans,and the hydraulic connection between layers is very weak.The analysis of the tritium concentration suggests that the average influence depth of the modern precipitation is approximately 120m.Based on the analysis of the 22 paleowater samples through the D18O method and 14C isotopic dating,the deep groundwater circulation in the fine sediments area of Beijing Plain down in the fringe part of alluvial-pluvial fans is relatively slow.On average the paleowater point occurs approximately below the 180m at these points.The main reasons for the formation of stratification and paleowater points are the water-blocking effect of the clay type strata and the compaction effect during the sedimentary process,especially the differential compaction,which could form closed or relatively closed stagnant aquifers.Groundwater in this kind of stagnant aquifers to some degree belongs to non-renewable resource,and should be reconsidered and re-arranged in the water resources management strategy. 展开更多
关键词 地下水循环 平原地区 迁移模型 北京 第四纪 冲积平原区 存储 不可再生资源
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Dynamic Analysis of Land Cover in Four-Lake Area of Jianghan Plain Based on MODIS-EVI Time Series Data 被引量:1
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作者 JIN Wei-bin XUE Lian XIONG Qin-xue 《Asian Agricultural Research》 2012年第12期44-48,共5页
According to the time series data of Enhanced Vegetation Index (EVI) in Four-Lake Area of Jianghan Plain during the period 2001-2007, we use Harmonic Analysis of Time Series (HANTS) to conduct cloud removing processin... According to the time series data of Enhanced Vegetation Index (EVI) in Four-Lake Area of Jianghan Plain during the period 2001-2007, we use Harmonic Analysis of Time Series (HANTS) to conduct cloud removing processing, and calculate the sum of square N of time series value of each pixel. The pixels with N>0.25 are classified as vegetation coverage area; the pixels with N<0.25 are classified as non-vegetation coverage area. As to vegetation coverage area, we use the second-order difference method to judge the frequency of peak value of EVI time series data. Within one year, the vegetation coverage area with peak value happening 1 time is woodland and grassland; the vegetation coverage area with peak value happening 2 times is arable land; the vegetation coverage area with peak value happening 3 times or more is vegetable land. Supervised classification method is used to identify cities, towns, water area in non-vegetation coverage area and woodland, grassland in vegetation coverage area. We draw the land cover classification diagram of Four-Lake Area in the period 2001-2007. In comparison with the land cover classification based on multitemporal ETM data in 2001, the difference of area of arable land is within 10%. Using MODIS-EVI data, we can rapidly and efficiently conduct land cover classification with low cost. The dynamic analysis results indicate that the area of arable land is in the process of declining, while the area of other cover types shows an increasing trend. 展开更多
关键词 Enhanced VEGETATION INDEX (EVI) LAND COVER classif
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Reflections on Plain Greening in Coastal Urban Areas: A Case Study of Plain Greening in the Main Urban Area of Taizhou
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作者 Zhang Yunsheng Lu Wenmei 《Meteorological and Environmental Research》 CAS 2018年第2期47-49,57,共4页
The current situation,existing problems and characteristics of greening in the main urban area of Taizhou were analyzed,and the construction ideas and safeguard measures of plain greening in urban areas in the new era... The current situation,existing problems and characteristics of greening in the main urban area of Taizhou were analyzed,and the construction ideas and safeguard measures of plain greening in urban areas in the new era were put forward. 展开更多
关键词 城市 沿海 案例 保护措施
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Evaluation of suitability area by ground source heat pump system in Baotou plain
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作者 WANG Chunpeng WANG Qinghua +2 位作者 FENG Lei FENG Ye CHENG Sanhuan 《Global Geology》 2014年第3期176-181,共6页
According to the elements of hydrogeological conditions,lithology,stratigraphic thermal physical parameters,construction technology and economic rational elements,the evaluation system of ground source heat pump( GSHP... According to the elements of hydrogeological conditions,lithology,stratigraphic thermal physical parameters,construction technology and economic rational elements,the evaluation system of ground source heat pump( GSHP) were established in Baotou plain. The factor weights were determined by using analytic hierarchy process,and the comprehensive element method was selected to evaluate the region suitability of GSHP system. The results show that the suitable area is 559. 63 km2 for utilizing GSHP in the studied area,accounting for 62. 58% of the total area; while the unsuitable area is 334. 60 km2,accounting for37.42%. The evaluating results can provide not only a scientific basis for development and utilization rationally of shallow geothermal heat in Baotou,but also offer an important reference to the other areas. 展开更多
关键词 地源热泵系统 评价体系 包头市 平原 适宜区 水文地质条件 适宜面积 层次分析法
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治涝导向的平原河网地区海绵城市实施路径探索——以宿迁市国家海绵城市示范系统化实施方案为例
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作者 魏锦程 程小文 +1 位作者 陈诗扬 任梅芳 《建设科技》 2024年第2期57-60,共4页
针对平原河网地区的排涝特征与问题,在梳理构建治涝片区排水格局的基础上分类提出了针对性的治涝策略。对于具有一定坡度。在多数时期可以实现自排的治涝片区,采用“上蓄+中分+下排”模式,分段缓解排涝压力,提高城区排涝标准对于整体地... 针对平原河网地区的排涝特征与问题,在梳理构建治涝片区排水格局的基础上分类提出了针对性的治涝策略。对于具有一定坡度。在多数时期可以实现自排的治涝片区,采用“上蓄+中分+下排”模式,分段缓解排涝压力,提高城区排涝标准对于整体地势低洼,在多数时期很难自排的治涝片区,采用“建闸营圩,蓄排并举”模式,将雨水排口分散建设小型雨水泵站的模式调整为片区排涝主干河道末端建设大型排涝泵站的模式,充分利用片区内部河网的输送和调蓄能力,增强城区应对暴雨的韧性。 展开更多
关键词 海绵城市 平原河网 治涝 系统化方案
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平原圩区水系结构与功能特征及其影响机制——以昆山南部为例
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作者 周可婧 孔繁花 +4 位作者 庄雪颖 班玉龙 尹海伟 杨子健 宋小虎 《生态学报》 CAS CSCD 北大核心 2024年第8期3268-3279,共12页
明晰平原河网水系结构和功能的影响机制对区域生态可持续发展具有重要意义。以昆山市南部防洪分区为例,选取水系指标分析圩区单元尺度下的水系网络结构与调蓄功能,并构建贝叶斯网络模型,综合考虑用地、自然、工程与政策管理等因子及其... 明晰平原河网水系结构和功能的影响机制对区域生态可持续发展具有重要意义。以昆山市南部防洪分区为例,选取水系指标分析圩区单元尺度下的水系网络结构与调蓄功能,并构建贝叶斯网络模型,综合考虑用地、自然、工程与政策管理等因子及其相互作用,定量探究水系结构与功能的影响机制。结果表明:(1)水系网络结构具有显著空间异质性,且水系调蓄功能与结构特征密切相关,较复杂的水系形态结构往往表现出较强的调蓄功能;(2)政策、工程、用地和自然条件等因子对水系调蓄功能的影响强度依次减弱;(3)识别水系功能优化目标下的关键变量与关键状态子集,可从社会⁃生态协同视角指导圩区单元的水系治理与优化。研究结果可为平原圩区水系网络健康与可持续发展提供理论参考和决策依据。 展开更多
关键词 平原圩区 水系结构与功能 贝叶斯网络模型 影响机制分析
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基于可拓理论的唐山市平原区地面沉降危险性评价
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作者 单强 汪洋 +3 位作者 马丙太 王颖 梁爽 陈社明 《河南科学》 2024年第2期232-241,共10页
地面沉降是一种缓变性的地质灾害,我国多个地区地面沉降比较严重,其次生地裂缝灾害凸显.对区域地面沉降危险性评价研究有利于灾害的科学防治.以唐山市平原区地面沉降为研究对象,采用可拓理论,基于因子分析方法建立地面沉降可拓评价模型... 地面沉降是一种缓变性的地质灾害,我国多个地区地面沉降比较严重,其次生地裂缝灾害凸显.对区域地面沉降危险性评价研究有利于灾害的科学防治.以唐山市平原区地面沉降为研究对象,采用可拓理论,基于因子分析方法建立地面沉降可拓评价模型,分析诱发地面沉降的影响因素,进行地面沉降危险性评价研究.结果表明:影响地面沉降发育的地层因素(贡献率为59.850%)包括第四系地层厚度和地下水主要开采层可压缩层(黏性土层)厚度;人为-现状因素(贡献率为16.687%)包括开采量、深层地下水位埋深、累计沉降量和沉降速率;水文-地貌因素(贡献率为8.642%)包括浅层地下水位埋深、地面高程和距水系距离.通过危险性可拓评价模型对各点位的地面沉降危险性程度,结合GIS软件将研究区划分为地面沉降高危险区、较高危险区、中危险区和低危险区,面积分别为305.93、4228.87、3152.99、653.21 km^(2).该研究为地面沉降危险性研究提供了新的方法,为地面沉降的防灾减灾工作提供了科学依据. 展开更多
关键词 因子分析 地面沉降 可拓理论 危险性评价 平原区
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平原沙土区河岸带不同植被类型对土壤团聚体稳定性的影响
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作者 王磊 刘晴廙 +5 位作者 史经攀 李俊杰 韩梦豪 陈斌 陈杭 关庆伟 《水土保持研究》 CSCD 北大核心 2024年第1期96-104,共9页
[目的]明晰不同植被类型对土壤团聚体稳定性及团聚体有机碳含量的影响,为平原沙土区河岸带土壤团聚体稳定性和抗蚀能力提升提供基础数据。[方法]以江苏省平原沙土区丰县复新河河岸带15年生杨树纯林、柳树纯林、杨柳混交林3种植被类型及... [目的]明晰不同植被类型对土壤团聚体稳定性及团聚体有机碳含量的影响,为平原沙土区河岸带土壤团聚体稳定性和抗蚀能力提升提供基础数据。[方法]以江苏省平原沙土区丰县复新河河岸带15年生杨树纯林、柳树纯林、杨柳混交林3种植被类型及对照为对象,用湿筛法对0—20 cm, 20—40 cm, 40—60 cm^(3)个层次土壤颗粒进行物理分级,测定了>0.25 mm团聚体含量(R0.25)、平均重量直径(MWD)、几何平均直径(GMD)、分形维数(D)及有机碳等主要指标,并利用线性回归对各指标相关性进行分析。[结果](1)试验地各土层团聚体以<0.25 mm微团聚体为主,占总团聚体含量的50.33%~80.00%。3种植被类型>2 mm和0.25~2 mm粒径团聚体含量高于对照,各土层中杨树纯林>2 mm大团聚体含量最高。(2)与对照相比,3种植被类型R0.25,MWD和GMD分别提高了41.77%~91.28%,29.89%~79.08%和37.60%~94.32%,其中杨树纯林效果最好。杨树纯林和柳树纯林D显著低于对照(p<0.05)。(3)试验地土壤团聚体有机碳含量范围为1.51~6.48 g/kg。与对照相比,3种植被类型下土壤团聚体有机碳含量提高了31.67%~71.68%,杨树纯林团聚体有机碳含量显著高于柳树纯林和杨柳混交林(p<0.05)。杨树纯林在0—20 cm土层各粒径团聚体有机碳含量最高。(4)线性回归分析表明土壤团聚体稳定性与有机碳显著相关,尤其是与大团聚体有机碳含量显著相关。此外,细根生物量、全氮含量、碳氮比和含水率也是影响团聚体稳定性的重要因素。[结论]平原沙土区河岸带杨树纯林更有利于提高土壤团聚体稳定性,增加土壤抗蚀能力。 展开更多
关键词 平原沙土区 河岸带 植被类型 团聚体稳定性 有机碳
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平原河网区生态流量阈值研究——以江汉平原典型河流为例
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作者 闫少锋 熊瑶 +3 位作者 吴可怡 刘昱 李芊芊 张翔 《中国水利》 2024年第7期40-45,共6页
生态流量是维系江河湖泊水生态系统的重要保障,而平原河网区水系错综复杂,传统生态流量计算方法适用性较差,开展平原河网区的河流生态流量阈值研究具有重要意义。以湖北省江汉平原典型河流为研究对象,从基本生态、特殊生境以及水环境保... 生态流量是维系江河湖泊水生态系统的重要保障,而平原河网区水系错综复杂,传统生态流量计算方法适用性较差,开展平原河网区的河流生态流量阈值研究具有重要意义。以湖北省江汉平原典型河流为研究对象,从基本生态、特殊生境以及水环境保护等方面开展平原河网区的生态流量阈值研究,以多样化、动态化的需水过程定义生态流量阈值,结果与实际相符,研究成果可为平原河网区生态流量阈值的确定及应用提供借鉴。 展开更多
关键词 生态流量 阈值 平原河网区 江汉平原
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基于高塔数据的山区丘陵与平原湖区风能参数差异分析
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作者 许杨 陈正洪 +1 位作者 申彦波 孟丹 《南方能源建设》 2024年第1期19-32,共14页
[目的]为促进风能资源开发的持续健康发展,为内陆地区风能资源的合理开发及利用提供科学依据,文章重点分析山区丘陵与平原湖区主要风能参数特征及差异。[方法]选用11个塔高为90~150 m的测风塔1整年观测资料,对湖北省山区、丘陵、平原及... [目的]为促进风能资源开发的持续健康发展,为内陆地区风能资源的合理开发及利用提供科学依据,文章重点分析山区丘陵与平原湖区主要风能参数特征及差异。[方法]选用11个塔高为90~150 m的测风塔1整年观测资料,对湖北省山区、丘陵、平原及湖区等5种不同地形形态下的主要风能参数特征及差异进行探讨。[结果]分析结果表明:(1)各塔高层风速日变幅在1.0~2.3 m/s,山区丘陵地形下变幅明显大于平原湖区,且各层变化趋于一致,均为白天小晚上大,平原湖区低层风速日变化与高层特征相反,为白天大晚上小;(2)各塔综合风切变指数在0.055~0.328之间,在山区丘陵地形下大于平原湖区,风切变指数日变幅在0.063~0.378,变化特征为白天小晚上大,平原湖区风切变日变幅明显大于山区丘陵,大风情况下的风切变在山区丘陵地形下分布较为离散,平原湖区地形下则相对较为集中,基本稳定在0.1~0.2之间;(3)各塔高层有效风速段年平均湍流强度为0.13~0.18,山区地形下大于平原湖区,各塔湍流强度日变幅在0.07~0.15,变化特征均为白天大晚上小,但山区丘陵地形下变幅明显大于平原湖区。[结论]不同地形下的风能资源特征在动力和热力作用下表现出明显的时空变化差异,分析结果可为风能资源开发利用提供指导。 展开更多
关键词 风能资源 测风塔 特征分析 山区丘陵 平原湖区 参数差异
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基于AHP-熵权法的鄞西平原河网水环境改善效果综合评价
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作者 宋炳坤 刘俊 +2 位作者 尹文昊 张晓峰 黄星宇 《水电能源科学》 北大核心 2024年第3期68-72,共5页
随着城市化的发展,河流间原有的联系被打断,水动力条件变差,继而引发水质污染、水生态功能衰退等问题。以鄞西平原为例,提出一种基于层次分析-熵权法的水环境改善效果评估方法,在水动力、水质参数的基础上,综合考虑经济效益和感官参数,... 随着城市化的发展,河流间原有的联系被打断,水动力条件变差,继而引发水质污染、水生态功能衰退等问题。以鄞西平原为例,提出一种基于层次分析-熵权法的水环境改善效果评估方法,在水动力、水质参数的基础上,综合考虑经济效益和感官参数,全面评估水环境改善方案的效果。量化比选研究区提升效果,最终确定方案3为研究区改善效果最优方案。研究表明,基于层次分析法和熵权法的综合评价方法相较于传统仅考虑水动力、水质或其他单一因素的评价方法,能够克服定性数据和主观赋权对评价结果的影响,更加全面地评价不同连通方案的提升效果,实现了方案综合评价与优选。 展开更多
关键词 平原河网地区 水系连通 层次分析法 熵权法
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平原水网地区开发区水土保持评估报告编制探讨
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作者 费国松 潘杰 +3 位作者 汪姗 胡尊乐 仲兆林 潘敏峰 《江苏水利》 2024年第3期1-6,16,共7页
探讨平原水网地区开发区水土保持区域评估报告编制的重点内容和存在的难点,并结合已批复的开发区水土保持区域评估报告,分析评估报告编制应注意的方面:①开发区水土保持评估报告编制大纲应参照国标并可做章节简化,体现整体性、全局性和... 探讨平原水网地区开发区水土保持区域评估报告编制的重点内容和存在的难点,并结合已批复的开发区水土保持区域评估报告,分析评估报告编制应注意的方面:①开发区水土保持评估报告编制大纲应参照国标并可做章节简化,体现整体性、全局性和指导性;②水土流失防治目标要结合个性指标并相应提出区域性控制指标;③土石方量可参考区内典型已验收生产建设项目的土石方挖填模数进行计算,土石方平衡遵循表土应剥尽剥,区内综合利用的原则;④要突出开发区水土保持总体布局和防治体系的完整性,明确单个防治分区的防治措施体系、防治标准和任务;⑤开发区管理机构应有明确的职责,实施负面清单制度。 展开更多
关键词 平原水网区 水土保持 功能定位 区域评估
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