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Balance of Water Supply-demand in Paddy Fields in Hilly Regions in Sichuan Province
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作者 张鸿 姜心禄 +1 位作者 樊红柱 郑家国 《Agricultural Science & Technology》 CAS 2012年第7期1489-1492,共4页
[Objective] The aim was to study the effects of water supply and consumption on water saving and drought resistance. [Method] Controlling field experiment was conducted to explore water balance between supply and dema... [Objective] The aim was to study the effects of water supply and consumption on water saving and drought resistance. [Method] Controlling field experiment was conducted to explore water balance between supply and demand in paddy fields in hilly regions in Sichuan Province. [Result] Rainfall in hilly areas was 3 611.10 m3/hm2; water for irrigation was 6 299.25 m3/hm2; evapotranspiration of rice was 6 424.95 m3/hm2; deep leakage was 2 459.55 m3/hm2; overflowing amount was 1 026.00 m3/hm2. In addition, water consumption totaled 8 884.50 m3/hm2 during rice production; water use was 0.99 kg/m3 and use efficiency of irrigated water was 1.40 kg/m3. [Conclusion] Water supply and consumption should be further organized to save water and fight against drought in hilly areas in Sichuan Province. 展开更多
关键词 RICE Water balance between supply and demand Sichuan Province Hilly areas
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THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR 被引量:9
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作者 GAOQian-zhao DUHu-lin 《Chinese Geographical Science》 SCIE CSCD 2002年第1期23-29,共7页
The Hexi Corridor is an important base of agriculture development inNorthwest China. According to recent statistics, there are 65. 94 x 10~8m^3 of water resourcesavailable in the Hexi Corridor. At present, net consump... The Hexi Corridor is an important base of agriculture development inNorthwest China. According to recent statistics, there are 65. 94 x 10~8m^3 of water resourcesavailable in the Hexi Corridor. At present, net consumption in development and utilization is 43. 33x 10~8m^3. Water supply and demand reach a balance on the recent level of production, but loss ofevaporation and evapotranspiration is as much as 25. 69 x 1010~8m^3. So net use efficiency of waterresources is 59% Based on analyzing balance between water and land considering ecologicalenvironment at present, there exists the serious water shortage in the Shiyang River system whereirrigation lands have overloaded. There is a comparative balance between supply and demand of waterresource in the Heihe River system; and the Sule River system has some surplus water to extendirrigation land. Use of agriculture water accounts for 83. 3% and ecological forest and grass for 6.9% . The Hexi Corridor still has a great potential for water saving in agriculture production.Water-saving efficiency of irrigation is about 10% by using such traditional technologies as furrowand border-dike irrigation and small check irrigation, and water-saving with plastic film cover andtechniques of advanced sprinkler and drip/micro irrigation etc. can save more than 60% of irrigatedwater. Incremental irrigation area for water-saving potential in the Hexi Corridor has beenestimated as 56% - 197% to original irrigation area. So the second water sources can be developedfrom water saving agriculture in the Hexi Corridor under Development of the Western Part of China inlarge scale. This potential can be realized step by step through developing the water-savingmeasures, improving the ecological condition of oasis agriculture, and optimizing allocation ofwater resources in three river systems. 展开更多
关键词 water resources balance between supply and demand water-saving potential ofagriculture hexi corridor
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The Supply and Demand of Agricultural Products in China Based on Balanced Diet 被引量:1
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作者 ZHOU Zhen-ya,ZHANG Qing,GAO Ming-jie,LI Jian-ping Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China 《Asian Agricultural Research》 2012年第8期5-10,共6页
Promoting agricultural production and ensuring the supply of agricultural products has always been the main task of agricultural development in China,but the agricultural production in China has not yet been combined ... Promoting agricultural production and ensuring the supply of agricultural products has always been the main task of agricultural development in China,but the agricultural production in China has not yet been combined with the Chinese residents' dietary needs to formulate reasonable development goals,with a certain blindness in production. According to the dietary standards in The Dietary Guidelines for Chinese Residents developed by the Chinese Nutrition Society,we calculate the demand of various types of agricultural products in China under the conditions of balanced diet. In comparison with the output of various types of agricultural products in China at present,we find that the output of most of agricultural products in China has exceeded the reasonable demand of the Chinese residents under the conditions of balanced diet. Therefore,adjusting the agricultural production structure in China and advocating balanced diet has become an important way to solve the problem of balance between supply and demand of agricultural products. 展开更多
关键词 balanceD DIET AGRICULTURAL products supply and DEM
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High Proportion Renewable Energy Supply and Demand Structure Model and Grid Impaction
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作者 Xiaoxia Wei Jie Liu +1 位作者 Tiezhong Wei Lirong Wang 《Journal of Power and Energy Engineering》 2016年第2期1-12,共12页
In considering of high proportion of renewable energy supply in 2050, the accelerating of energy consumption gross, source and environment can affect the energy system restrict affection are stronger. Add wind and sol... In considering of high proportion of renewable energy supply in 2050, the accelerating of energy consumption gross, source and environment can affect the energy system restrict affection are stronger. Add wind and solar to electricity energy with large amount of energy source exploitation. The energy source amount per person is lower. Considering the renewable energy amount and supply, primary energy storage and structure problem is standing out. Before the wide spread of renewable energy, Using the high-carbon energy in China can pollute seriously. Chinese energy supply and demand problem is research key point. This paper researches Chinese energy supply and demand pattern system and evaluation methodology, gives out the inner and outer influencing elements. And evaluate Chinese energy supply and demand pattern from energy gross, structure, distribution and transportation. Use energy supply synthesize radar comparison chart in certain time period. From energy security, economy, clean and efficiency, analyze the benefit comparisons of Chinese energy supply and demand pattern. This energy supply and demand pattern model will give one certain theoretical analysis and practice reference to the further high proportion of renewable energy. 展开更多
关键词 high Proportion of Renewable Energy supply Inner and Outer Element Power Grid Affection supply and demand Pattern
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The Estimation of Water Supply and Demand in Hotan Oasis
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作者 杨依天 杨佳禾 魏胜利 《Agricultural Science & Technology》 CAS 2016年第3期742-746,750,共6页
[Objective] The purpose of this study is to estimate water supply and demand, which can provide a basis for how to allocate rationally water resources in Hotan Oasis. [Method] The water supply and demand in Hotan Oasi... [Objective] The purpose of this study is to estimate water supply and demand, which can provide a basis for how to allocate rationally water resources in Hotan Oasis. [Method] The water supply and demand in Hotan Oasis in the next15 years were calculated according to water-soil balance. [Result] When the runoff of Hotan River is at a probability of 50%(P=50 for short), the total water resource is 50.57×10^8m^3, and there is only 33.13×10^8m^3available for social and economics,but there would be a need of 33.44×10^8and 36.06×10^8m^3, and the water shortage would be 1.31 ×10^8and 2.93 ×10^8m^3in 2020 and 2030 respectively. When P =75,the total water resource is 44.30×10^8m^3, there is only 29.39×10^8m^3water available for social and economics. However, there would be a need of 31.43 ×10^8and33.11×10^8m^3, and the water shortage would be 2.04×10^8and 3.72×10^8m^3in 2020 and 2030, respectively. [Conclusion] The problem of water shortage would be serious over the next 15 years, and the fragile ecosystem would be destroyed dramatically with the large-scale land reclamation against natural laws. Hence, the effective policies and measures should be taken timely to prohibit reclamation and to cope with ongoing water shortage, based on the water supply and demand estimation under the background of climate change. 展开更多
关键词 ESTIMATION Water-soil balance Water supply and demand Hotan Oasis
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Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China 被引量:11
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作者 JI Xi-bin KANG Er-si +3 位作者 CHEN Ren-sheng ZHAO Wen-zhi XlAO Sheng-chun JIN Bo-wen 《Agricultural Sciences in China》 CAS CSCD 2006年第2期130-140,共11页
Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance o... Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year (2003), the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system. 展开更多
关键词 middle reaches of Heihe River irrigation region water resources supply and demand balance evaluation of the security of water resources
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Supply and Demand Information
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《China's Foreign Trade》 2001年第6期45-45,共1页
关键词 high supply and demand Information
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Analysis on the Situation of Power Supply and Demand in Shandong
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作者 Sun Wei Department of Development Planning, Shandong Electric Power Corporation Jia Yulu 《Electricity》 2008年第1期40-42,共3页
In the first half of 2007, the power industry in Shandongprovince continued to maintain a rapid growth momentum.The gross electricity consumption amounted to 121.25 TWh,14.4% higher over that in the same period of las... In the first half of 2007, the power industry in Shandongprovince continued to maintain a rapid growth momentum.The gross electricity consumption amounted to 121.25 TWh,14.4% higher over that in the same period of last year. The totalinstalled capacity reached 53.29 GW. It was expected that bythe end of 2007, the gross electricity consumption in Shan-dong would reach 260 TWh, increasing by 14.4% on ayear-on-year basis; the maximum load would reach 40. 展开更多
关键词 Analysis on the Situation of Power supply and demand in Shandong high
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我国城市幼儿园空间布局适配性的现状、成因与优化建议 被引量:4
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作者 蔡迎旗 崔财艳 +1 位作者 资明贵 张春艳 《学前教育研究》 CSSCI 北大核心 2024年第1期24-37,共14页
供需适配的幼儿园空间布局是促进学前教育资源均衡配置的关键举措,能有效推动学前教育高质量发展。本研究以我国中部地区某省会城市主城区759所幼儿园为例,运用地理信息分析工具中的核密度估计、最近邻指数等方法,分别从“有园上”“入... 供需适配的幼儿园空间布局是促进学前教育资源均衡配置的关键举措,能有效推动学前教育高质量发展。本研究以我国中部地区某省会城市主城区759所幼儿园为例,运用地理信息分析工具中的核密度估计、最近邻指数等方法,分别从“有园上”“入园近”“上好园”“园幼共生”四个维度对幼儿园空间布局是否存在错配的核心议题进行深入剖析。研究发现:该市部分幼儿园空间分布存在欠适配现象,且形成了空间与结构错配的问题,其主要原因是资源投入层面的财政失衡、需求提出层面的逐优心理和城市规划层面的建设滞后。本文建议通过构建数字化管理平台、优化供需对接机制、加强配套园治理、加大治薄扶弱补缺的力度等措施,推动幼儿园空间布局从错配到适配的转换,从而促进区域学前教育公共服务一体化和高质量发展。 展开更多
关键词 幼儿园 空间布局 供需适配 高质量发展 优化建议
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中药饮片产业发展现状及供给侧问题与对策 被引量:2
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作者 郁红礼 李林 +8 位作者 金传山 杜伟峰 马恩耀 张伟 季德 张兴德 彭瑞潭 申诺 陆兔林 《中国现代中药》 CAS 2024年第3期439-446,共8页
分析了中药饮片产业及市场规模现状,相关法律、法规、政策等,从供给侧剖析产业发展瓶颈,解析中药饮片生产标准化、规模化程度低,技术及产品创新不足,缺少协调供需平衡的宏观统筹问题,提出加强炮制理论基础研究、提高中药饮片生产标准化... 分析了中药饮片产业及市场规模现状,相关法律、法规、政策等,从供给侧剖析产业发展瓶颈,解析中药饮片生产标准化、规模化程度低,技术及产品创新不足,缺少协调供需平衡的宏观统筹问题,提出加强炮制理论基础研究、提高中药饮片生产标准化水平的对策措施,包括提高中药炮制技术的标准化水平、完善质量控制标准、建立等级标准等,倡导提高产业规模化水平、实施大品种战略、鼓励科技创新、组建创新联合体,加快中药饮片数字化、智能化生产管理研发及新产品研发,并从调控供需平衡角度提出了推进中药饮片区域化生产与流通的措施等,以期构建以高品质中药饮片为核心的创新型产业发展格局,探寻振兴中药饮片产业高质量发展之路。 展开更多
关键词 中药饮片产业 发展现状 标准化 规模化 供需平衡 创新生产
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山地多中心城市公园绿地生态系统文化服务供需匹配特征 被引量:1
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作者 骆畅 王方民 +1 位作者 李高高 杨朝现 《生态学报》 CAS CSCD 北大核心 2024年第13期5816-5827,共12页
城市公园绿地为居民提供了重要的生态系统文化服务,在促进居民身心健康和提高社会福祉方面发挥着关键作用。以典型山地城市重庆中心城区为例,构建供需匹配评估体系,利用多源数据量化供给与需求,识别供需平衡与协调发展关系。结果表明:(1... 城市公园绿地为居民提供了重要的生态系统文化服务,在促进居民身心健康和提高社会福祉方面发挥着关键作用。以典型山地城市重庆中心城区为例,构建供需匹配评估体系,利用多源数据量化供给与需求,识别供需平衡与协调发展关系。结果表明:(1)重庆市中心城区城市公园绿地生态系统文化服务供需具有显著空间异质性,供给呈北高南低、分散布局的格局,需求呈中心高、外围低的格局;(2)生态系统文化服务供需失衡特征显著,其中52.38%的组团文化服务供给滞后,33.33%的组团属于供给超前状态;供需耦合协调指数平均值为0.50,协调发展程度空间分布呈“中心高、外围低”格局;(3)综合分析供需均衡与耦合协调结果发现,由于供给超前导致了外围城市组团的失调发展,而城市中心区域组团在供给滞后状态下维持了中等水平协调发展程度。总体来看,重庆市中心城区各组团存在不同程度的公园绿地生态系统文化服务供需错配,基于评估提出针对性的城市公园绿地优化策略,可为公园绿地的合理配置与规划提供重要支持。 展开更多
关键词 城市公园绿地 生态系统文化服务 山地城市 供需平衡 协调发展
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我国健身服务业高质量发展的推进路径——基于供需平衡理论 被引量:1
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作者 吴越 左为东 《湖北体育科技》 2024年第2期92-96,共5页
健身服务业作为体育产业的重要组成部分,基于其潜在的市场考验和广阔的发展前景,本文采用文献资料、专家访谈、逻辑分析等方法,分析供需平衡理论框架下健身服务业高质量发展的宏观形态。从健身服务市场主体发展态势看,我国传统健身服务... 健身服务业作为体育产业的重要组成部分,基于其潜在的市场考验和广阔的发展前景,本文采用文献资料、专家访谈、逻辑分析等方法,分析供需平衡理论框架下健身服务业高质量发展的宏观形态。从健身服务市场主体发展态势看,我国传统健身服务市场主体虽已发展成熟,但存在盈利模式单一、价值增值能力弱、供需错位以及结构失衡等诸多问题;从健身服务市场客体看,我国消费出现有效需求转化、广泛人群需要层次提升、潜在消费人口发展、消费理性预期改善、消费内容空间扩大等变化。因此,必须形成“三位一体”,即政策、供给、需求的健身服务经济价值新路径,以推进健身服务业高质量发展。 展开更多
关键词 健身服务业 供需平衡 体育产业 经济价值
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把握数字消费高质量发展的着力点 被引量:3
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作者 毛中根 贾宇云 《东北财经大学学报》 2024年第2期3-13,共11页
推进经济高质量发展必须构建以国内大循环为主体、国内国际双循环相互促进的新发展格局,发挥消费对经济发展的基础性作用。数字经济快速发展,引发居民消费发生巨大变革,在消费主体、消费客体和消费环境方面,数字消费都呈现出典型的新特... 推进经济高质量发展必须构建以国内大循环为主体、国内国际双循环相互促进的新发展格局,发挥消费对经济发展的基础性作用。数字经济快速发展,引发居民消费发生巨大变革,在消费主体、消费客体和消费环境方面,数字消费都呈现出典型的新特征。数字消费有助于提升消费需求、有助于推动产业结构升级、有助于促进供需匹配。应着力于消除城乡消费差距过大、推进新型基础设施建设、培育供需匹配创新动力和推进数字消费治理升级等多个方面,助推数字消费高质量发展,加快构建双循环新发展格局。 展开更多
关键词 数字消费 消费升级 高质量发展 供需匹配 新发展格局
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区块链赋能全民健身公共服务供给治理研究 被引量:3
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作者 贾炳涛 邹青海 《辽宁体育科技》 2024年第1期42-48,共7页
运用文献资料法,探究区块链赋能全民健身公共服务供给治理的理论框架、变革向度及精准路径。研究认为:基于“服务金三角”理论模型构建全民健身公共服务供给治理框架,从服务需求重构、供给战略重构、供给系统重构、供给主体重构等方面... 运用文献资料法,探究区块链赋能全民健身公共服务供给治理的理论框架、变革向度及精准路径。研究认为:基于“服务金三角”理论模型构建全民健身公共服务供给治理框架,从服务需求重构、供给战略重构、供给系统重构、供给主体重构等方面诠释变革向度。并提出建构“链式”管理、“公有链”运作平台、需求精准管理和供给科学决策、创新赋能机制的供给实践框架,从供给需求、供给战略、供给系统、供给主体层面阐释区块链嵌入供给治理风险,为规避风险提出政府、企业、社会、个体应对路径。 展开更多
关键词 区块链赋能 全民健身公共服务供给 服务金三角理论模型 全民健身 供需平衡
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供需平衡视角下昆仑山北坡县域单元地表水资源开发利用潜力初探
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作者 周洪华 杨玉海 +1 位作者 朱成刚 方功焕 《干旱区地理》 CSCD 北大核心 2024年第7期1106-1115,共10页
定量分析地表水资源开发利用潜力有助于明晰区域水资源禀赋,对区域未来水资源科学规划和可持续开发利用具有重要的指导意义。通过供需水量平衡,从地表径流量、生态需水量、地表水可利用量角度,初步探讨了昆仑山北坡县域单元的地表水资... 定量分析地表水资源开发利用潜力有助于明晰区域水资源禀赋,对区域未来水资源科学规划和可持续开发利用具有重要的指导意义。通过供需水量平衡,从地表径流量、生态需水量、地表水可利用量角度,初步探讨了昆仑山北坡县域单元的地表水资源开发利用潜力,以期为昆仑山北坡科学规划和兵团南进布局提供水资源保障依据。结果表明:(1)昆仑山北坡河流径流2000年后呈显著增加趋势,主要河流2001—2010年年均径流量较2000年以前平均增加了23.36%,2011—2020年较2000年以前平均增加了42.89%,其中车尔臣河增幅最大,和田河增幅最小。(2)车尔臣河流域、克里雅河流域和和田河流域的生态基流量分别为4.67×10^(8)m^(3)、5.38×10^(8)m^(3)和20.26×10^(8)m^(3),天然植被生态需水量分别为4.34×10^(8)m^(3)、4.00×10^(8)m^(3)和2.62×10^(8)m^(3)。(3)昆仑山北坡各县域单元现状地表水已用水量范围为0.1×10^(8)~8.73×10^(8)m^(3),地表水资源潜力范围为-0.07×10^(8)~3.17×10^(8)m^(3),空间差异非常显著,其中水资源潜力大于2.00×10^(8)m^(3)的有墨玉县、铁门关市38团、策勒县、且末县、和田县、民丰县和洛浦县。现状区域的地表水资源调蓄能力不足,水资源利用上限偏低,虽有潜力但有水难用,未来昆仑山北坡各县域单元需制定修编更为适宜的地表水资源规划并加强基础水利工程建设,提升地表水资源利用效率,为区域高质量发展提供水资源支撑保障。 展开更多
关键词 昆仑山北坡 地表径流 供需平衡 生态需水 地表水资源潜力
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基于生态需水的黄河中游水平衡分析--以沁河流域为例
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作者 刘义 史佩东 +3 位作者 刘淼 许凯然 张宁 姜鹏 《水文地质工程地质》 CSCD 北大核心 2024年第1期30-40,共11页
为推动黄河流域生态保护及高质量发展,解决地表水资源供需矛盾,亟需开展水平衡分析,建立水平衡模型,为水资源合理分配提供参考依据。作为黄河的重要支流,沁河流域位于黄河中游末端,由于近年来上游调水政策的施行以及流域内生活、生产用... 为推动黄河流域生态保护及高质量发展,解决地表水资源供需矛盾,亟需开展水平衡分析,建立水平衡模型,为水资源合理分配提供参考依据。作为黄河的重要支流,沁河流域位于黄河中游末端,由于近年来上游调水政策的施行以及流域内生活、生产用水的增加,用水矛盾突出,出现了河道断流、入黄水量偏枯等问题。为保障河流生态环境健康,优化引沁入汾跨流域提水工程实施后的流域水资源供需平衡,以2021年为现状年,在“自然-人工”二元水循环研究理论的指导下,运用水平衡分析理论与方法,以河道内生态需水为保障基础,对沁河流域水资源需求、供水能力与供需平衡进行了分析与讨论。结果表明:(1)沁河流域水资源供给和需求在空间分布上具有分异性,上游山西省境内各河段河道内均能够保障适宜的生态需水量,下游河南省境内,仅可满足最小生态需水量;(2)沁河流域可供给水资源总量为10.04×10^(8)m^(3),河道外生产、生活及生态用水总量为8.89×10^(8)m^(3),剩余河道内水量仅为1.15×10^(8)m^(3),仅可满足河流最小生态需水;(3)推算至2030年,流域内工业生产及生活取用地表水量将达到6.98×10^(8)m^(3),河道外用水总量将达到9.81×10^(8)m^(3),剩余水量无法满足最小生态需水。建议采用降低工业用水量、提高农田灌溉用水利用率、推广使用高效节水技术,进一步增强水资源的有效利用,改善流域生态环境。研究结果可为合理规划沁河流域水资源调度提供参考,也可为黄河中游水平衡分析提供范例。 展开更多
关键词 水资源 生态需水 供需平衡 沁河 需水预测 黄河中游
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数字经济赋能消费升级:微观机制和关联效应
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作者 金晶 董敬畏 《技术经济与管理研究》 北大核心 2024年第7期56-63,共8页
数字经济发展是高质量建设共同富裕示范区的重要动力。居民消费升级是实现共同富裕目标的重要成果之一。供需双侧在数字化转型的过程中产生新的增量,推动供需双侧实现更高水平的平衡。通过逻辑推演,阐释消费升级是高质量发展实现共同富... 数字经济发展是高质量建设共同富裕示范区的重要动力。居民消费升级是实现共同富裕目标的重要成果之一。供需双侧在数字化转型的过程中产生新的增量,推动供需双侧实现更高水平的平衡。通过逻辑推演,阐释消费升级是高质量发展实现共同富裕的逻辑终点,是共同富裕实现程度的重要参照;分析数字经济对深化供给侧结构性改革和增加有效需求的驱动作用。通过理论分析,以市场经济一般均衡理论为基础,阐释数字经济在创造新的供需动态平衡,追求市场最优的过程中实现消费升级的微观机制。同时,以浙江省为例进行有限的实证分析,通过灰色关联度分析和中介效应分析验证数字经济赋能下,供需双侧驱动消费升级的路径有效性和存在的阻滞点。 展开更多
关键词 数字经济 消费升级 供需平衡 高质量建设
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水生态系统韧性视角下热带雨林地区的蓝绿空间评价——以五指山市南圣河为例
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作者 车乐 李媛钰 +1 位作者 赵渺希 叶鸿任 《热带地理》 CSCD 北大核心 2024年第4期709-723,共15页
热带雨林地区因特殊的气候特点及空间特征,河流蓝绿空间面临的雨洪压力与人类社会活动压力较大,其韧性建设对于整个生境具有关键性影响。国内外研究聚焦于韧性承洪实践与韧性评估量化,鲜有基于不同生态压力冲击对河流蓝绿空间开展多维... 热带雨林地区因特殊的气候特点及空间特征,河流蓝绿空间面临的雨洪压力与人类社会活动压力较大,其韧性建设对于整个生境具有关键性影响。国内外研究聚焦于韧性承洪实践与韧性评估量化,鲜有基于不同生态压力冲击对河流蓝绿空间开展多维韧性评价。文章以南圣河为对象,基于雨洪等自然灾害的脉冲式压力与人类社会对生态系统施加的慢性压力两类情境,构建水生态系统的“压力-脉冲-韧性”模型,通过“构建理论模型―叠合双维承压评价―解析吻合/冲突点―探析韧性策略”的逻辑方法实现特定地域蓝绿空间的评价与优化。研究发现:1)生态系统服务价值越高,调节功能越高,蓝绿空间韧性越强。2)突发性脉冲方面,在极端日降雨量增加情景下,河流水系的缓冲半径与水源类型密切相关,水库受到水安全威胁的风险大于河流,地表的径流曲线数值(简称CN)一般与历史经验相关。3)慢发性压力方面,韧性压力与城市人口密切相关,人口越密集,韧性压力越大;且不同季候的游憩密度与丰枯期存在分异,丰水期雨洪威胁大,游憩密度低,枯水期雨洪威胁小,游憩密度高。 展开更多
关键词 水生态系统 压力-脉冲-韧性 热带雨林地区 蓝绿空间评价 供需平衡 五指山市
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基于一元线性回归模型的供水网络中水表读数虚高问题研究 被引量:1
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作者 韩义秀 《浙江工贸职业技术学院学报》 2024年第1期70-73,84,共5页
为了定量研究供水网络中总表漏水程度和分表读数虚高程度,根据水量平衡分析法的原理,结合大数据分析技术,建立了一元线性回归方程,回归常数代表总表漏水量程度,回归系数代表分表读数虚高程度。通过针对2021年某高校供水管网的实证研究表... 为了定量研究供水网络中总表漏水程度和分表读数虚高程度,根据水量平衡分析法的原理,结合大数据分析技术,建立了一元线性回归方程,回归常数代表总表漏水量程度,回归系数代表分表读数虚高程度。通过针对2021年某高校供水管网的实证研究表明,总表日均漏水量为15.5958吨,分表读数虚高率为1.07%。该方法对供水管网漏损率的精准评估等问题的解决提供了新的思路和方法。 展开更多
关键词 供水网络 水量平衡分析法 一元线性回归模型 漏水量 虚高
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2024年我国无烟煤市场发展与展望
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作者 冯雨 杨玲 杨小敏 《中国煤炭》 北大核心 2024年第4期27-35,共9页
通过对宏观政策以及产业政策动态等多维度进行剖析,对无烟煤下游行业的消费现状和趋势进行详细分析和预测。介绍了我国无烟煤资源分布、生产和进口现状,对我国无烟煤生产和进口趋势进行了预测。综合分析供需、成本、政策等影响无烟煤价... 通过对宏观政策以及产业政策动态等多维度进行剖析,对无烟煤下游行业的消费现状和趋势进行详细分析和预测。介绍了我国无烟煤资源分布、生产和进口现状,对我国无烟煤生产和进口趋势进行了预测。综合分析供需、成本、政策等影响无烟煤价格的因素,特别是需求和供应关系,对2024年无烟煤价格走势进行了定性分析。整体认为,2024年,我国无烟煤将处于供需紧平衡状态,但较2023年略有宽松;价格中枢有望小幅下移,但仍将处于相对较高的位置。 展开更多
关键词 无烟煤市场 无烟煤消费 无烟煤供应 供需平衡 煤炭价格
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