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1.
本文采用奥多姆(Odum H T)的能值分析方法,针对山西省2000年~2016年生态经济系统的主要能值投入与产出、运行效率以及环境负荷作了系统分析,并通过构造生态经济系统能值评估体系分析区域实体经济发展的整体趋势及可持续性.结果表明:山西省经济发展状况仍然十分滞后,主要由于工业与煤炭资源息息相关,产业单一,抗风险能力差.从2000年到2016年,可更新资源能值量基本保持在3.56E+22sej,无显著变化差异;人均能值量从1.94E+15sej提升到2.66E+15sej;环境负荷率(ELR)从0.77提升到1.74;生态经济系统能值投资率从0.59提升到1.07.能值可持续指标从3.44降到1.10,可持续性有所改善.  相似文献   

2.
基于能值分析的县域耕地利用效益比较研究   总被引:1,自引:0,他引:1  
采用能值分析法,在对耕地利用效益内涵界定的基础上构建评价能值指标体系,以湖北省资源型城市潜江、轻工业型城市仙桃、生态旅游型城市鹤峰3种不同类型的县市为研究对象,测算2010年的各县市的耕地利用效益能值效率.研究结果表明:①2010年潜江市耕地利用产生的社会效益最好,粮食安全保障度能值达到1.944E+17sej/hm2,粮食安全度最高,农村人均能值量为1.45E+16sej/hm2,农民生活最好,仙桃次之;②2010年仙桃市耕地利用产生了最好的经济效益,耕地集约度达到1.38E+16sej/hm2,土地集约利用度最高,潜江次之;③2010年鹤峰耕地利用生态效益最高,耕地利用的挖掘潜力最大.研究结果对不同类型城市如何挖掘耕地系统的持续生产能力、缓解粮食安全压力具有一定的指导意义.  相似文献   

3.
引用2010—2014年相关统计数据,采用能值分析方法,对黑龙江省富锦市的人均能值用量、电力能值使用量比、能值-货币比率、能值功率密度、废弃物能值比率、人口承载力、能值自给率等指标进行了研究,同时与其他地区的相关指标进行了比较,系统分析了富锦市生态经济系统的发展状况.结果表明:(1)2010—2014年,人均能值用量虽有增长但仍很低,表明富锦市居民平均生活水平依然很低;富锦市的电力能值使用量比从11.54%上升到16.80%,虽有上升但仍很低.(2)富锦市的能值-货币比率从2010年的9.52×1012sej/$下降到2014年的5.97×1012sej/$,表明近几年富锦市的经济有所发展,但经济开发程度依然很低.(3)富锦市的能值功率密度低于世界能值功率密度的平均水平,但高于泰国和印度,说明富锦市具有一定的发展潜力.(4)2010—2014年,废弃物能值比率虽有上升但仅升为3.4%;富锦市的人口承载力有减少的趋势;富锦市的能值自给率虽有下降但仍很高,表明富锦市的经济发展程度低且对当地自然资源的依赖程度高.  相似文献   

4.
宁夏生态经济系统能值分析   总被引:2,自引:0,他引:2  
运用能值理论对宁夏生态经济系统进行了分析,计算得出宁夏总能值用量为8.74×1022sej,可更新资源为5.89×1021sej,可更新资源产品为1.83×1022sej,不可更新资源为7.99×1022sej,货币流为8.02×1022sej,废弃物为6.55×1022sej.在此基础上,编制了宁夏生态经济系统能值评估表,选取环境负载率、能值自给率、能值货币比率、电力能值比率、人均能值用量、能值使用强度等6个能值指标与部分省份和国家对比分析,认为宁夏目前的发展模式主要是一种高资源消耗型经济,经济发展主要建立在对本地不可更新资源的开发利用上.因此,应改变发展模式,调整产业结构,提高资源利用率,加强反馈能值的引入,发展绿色无公害产品,增加产品附加值,促进生态经济系统健康可持续发展.  相似文献   

5.
为促进干旱区城市可持续发展,以乌鲁木齐城市系统为例,基于2004和2010年统计数据,利用相图法分析得出:2003和2009年系统对不可更新自然资源的利用比例极大,对可更新自然资源利用比例最小;6年间系统对自然资源利用比例下降,尤其对可更新资源利用比例下降显著,为33.84%,而社会反馈投入能值比例上升;两年系统虽都处于可持续发展状态,但可持续发展指数有所下降且均接近下限。欲提升系统可持续发展性能,必须合理调整其能值利用结构。  相似文献   

6.
以能值理论为基础,选择舟山市东极贻贝养殖生态系统为研究对象,在定量分析贻贝养殖生态系统的物质流和能量流的基础上,通过建立能值评价指标体系,综合评价东极贻贝养殖对环境的影响及其可持续性。结果表明:东极贻贝养殖生态系统的太阳能值转化率TR为3.35E+09sej/g,环境负荷率ELR为0.45,能值产出率EYR为3.22,能值投入的生产效率PEEI为9.60E-10g/sej,系统可持续发展指数ESI为7.16。最后将其与其它四种养殖系统进行比较,分析得出贻贝养殖生态系统能值产出率和可持续性均较高。  相似文献   

7.
为探究农业循环经济在土壤侵蚀区的适应性与发展潜力,选取福建省长汀县典型农户循环经济(模式Ⅰ)及传统类型(模式Ⅱ)进行能值流动比较,并运用净能值产出率(EYR)、能值投资率(EIR)环境负载率(ELR)、可持续性发展指数(ESI)、能值投入密度及能值反馈率指标进行评价.结果表明:模式Ⅰ的EYR、EIR、ELR分别是模式Ⅱ的4.15倍、1.13倍和0.15倍,模式Ⅰ经济发展程度相对较高,对环境的依赖相对较弱;从可持续性指数方面可得出,模式Ⅰ与模式Ⅱ的能值ESI分别为6.85,0.26,表明模式Ⅰ具有活力与发展潜力,模式Ⅱ属于消费型经济系统,不具有可持续性;模式Ⅰ的能值投入密度为1.90E+12 sej,高于模式Ⅱ的1.66E+12 sej,模式Ⅰ开发程度和集约化程度比模式Ⅱ高,结构较为合理;模式Ⅰ能值反馈率为4.3%,具有一定的主动调节、组织能力.因此总体上说,红壤侵蚀区循环经济模式具有更高的经济效益和环境效益,可推动当地农户可持续发展.  相似文献   

8.
从渤海海峡跨海通道"零替代方案"的研究视角出发,构建了社会经济与生态环境协调发展评价指标体系,对山东省生态经济系统协调发展进行测度,并用GM(1,1)模型对结果进行预测.结果表明:2003-2012年社会经济效益与生态环境效益呈现出上升的趋势,2003-2012年山东省社会经济与生态环境协调发展度状况良好.根据发展状况,协调发展度可以明显分为3个阶段:2003-2004年为初级协调发展阶段,2005-2009年为中等协调发展阶段,2010年后开始转入良好协调发展阶段.GM(1,1)模型预测结果显示,生态经济系统协调度和协调发展度发展趋势将总体上处于先上升后下降状态,且下降趋势明显.  相似文献   

9.
<正>西藏水资源生态足迹评价与动态预测水资源是人类生存之根本,是社会发展之命脉,随着水危机的日益加剧,水资源短缺已成为全球关注的热点问题。生态足迹概念是用来评价生态可持续发展状况的一种方法。西藏大学赵忠瑞等使用生态足迹模型评估了2003—2012年西藏自治区的水资源状况,结果表明:西藏水资源生态足迹2003—2008年间由0.0154 hm2·人-1上升至0.0212 hm2·人-1,2009—2012年逐渐下降,10年平均水资源生  相似文献   

10.
厦门市生态环境与社会经济协调发展研究   总被引:1,自引:0,他引:1  
以厦门市全域为研究区域,通过采用熵值赋权法确定各项指标权重,建立厦门市生态环境与社会经济协调发展度评价模型,对该区域2003-2012年间生态环境、社会经济系统内部各要素层间的协调性及其两系统间的总体协调发展度进行了定量评价与分析.分析结果表明:厦门市生态环境系统、社会经济系统内部协调性整体良好,且两系统间协调发展状况总体呈现比较稳定的上升趋势,但二者协调发展进程较为缓慢,在近10 a间均属于中度失调发展类型.值得注意的是,在此期间两者的协调发展水平呈现出明显的阶段性特征,即2003-2007年为城市社会经济滞后型,2008年变为生态环境滞后型,2009-2010属于城市社会经济滞后型,2011-2012年又转变为生态环境滞后型,二者在相互协调发展中具有交替式上升的特征.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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