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1.
Ling Feng 《寒旱区科学》2010,2(2):0175-0184
"The value of the world's ecosystem services and natural capital" by R.Costanza et al.in 1997 is generally regarded as a monument to the research of valuing ecosystem services.However,the classification of ecosystem services,the method of various services summation,and the purpose for static global value had many criticisms.Based on a summary of these criticisms and suggestions,further study direction—on the sustainability of ecosystem services—is presented.The two basis indicators in ecology—productivity and biodiversity,respectively characterize the ability of producing and self-organizing—not only represent the internal function of ecosystem,but also can be proportioned to its external function of supporting and providing for human life.Theoretically,the two indicators combined could physically assess the sustainability of ecosystem services based on the traditional procedure of Costanza's.The case study of Hohhot City in 1995-2005 shows that the new model reflects the changes of ecosystem services at spatial and temporal scale,and the functionally adjusted assessment shows the sustainability of Hohhot City became gradually stronger during the study decade.But due to the enormous value per unit of water ecosystem,the minimal loss of water area leads to the final result being opposite to the processing analysis,which gives a clue to the further experimental testing research.  相似文献   

2.
正The workshop on the innovative development of Sciences in Cold and Arid Regions(SCAR)was successfully held on October 14,2017 in Lanzhou Library of Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences.Academician Guodong Cheng—Editors-in-chief of SCAR—hosted the meeting,more than 20 experts from Lanzhou University,Northwest Normal University and Northwest Institute of Eco-Environment and Resources attended this conference.  相似文献   

3.
(1) A General Statement.— The west part of Tao-ho which has become ourdominion since the Han Dynasty is still obscure for its geography. It containsnine districts of Kansu Province and two districts of Kokonor Province, andholds an important position in the development of the north-west China.  相似文献   

4.
P2082006010929地学信息体视化中3维交互技术的研究与实现=The re-search and realization of3Dinteractive techniques for the vol-ume visualization of geo-information/颜辉武,马晨燕…∥测绘学报.—2005,34(1).—64~70图8参11(作者)CheTP3112006010930多尺度时空数据的集成与对象进化模型=The integration ofmulti-scale spatiotemporal data and the object evolution model/佘江峰,冯学智…∥测绘学报.—2005,34(1).—71~77图7参23(郭梅菊)CheP333.62006010931基于Brown-Forsythe检验的水文序列变异点识别=Brown-Forsythe bas…  相似文献   

5.
Face-to-face interviews(n=860) were conducted to determine cash-gift behavior, cognition and complexity of social relations, and family water consumption for agricultural production in a typical oasis area in Northwest China. The survey results revealed cash gifts to be the second-largest expenditure(1,330 Yuan) for rural households, far beyond the average spending on health(854.1 Yuan) or education(890.8 Yuan). The amount of cash-gift expenditures indirectly reflects a family's social relations level, and our developed Social Relations Extent Coefficient—based on cash-gift and food expenditures—can directly reflect the extent or level of these relationships. Different types of farmers or farming families have different coefficients. The coefficient also shows how social station affects a family's water resource utilization, and how water is distributed among different types of farmers. Despite the current inequities, however, promotion of better agricultural techniques and large-scale cultivation in this area could help distribute water resources more equitably and effectively.  相似文献   

6.
Phenological modeling is not only important for the projection of future changes of certain phenophases but also crucial for systematically studying the spatiotemporal patterns of plant phenology. Based on ground phenological observations, we used two existing temperature-based models and 12 modified models with consideration of precipitation or soil moisture to simulate the bud-burst date(BBD) of four common herbaceous plants—Xanthium sibiricum, Plantago asiatica, Iris lactea and Taraxacum mongolicum—in temperate grasslands in Inner Mongolia. The results showed that(1) increase in temperature promoted the BBD of all species. However, effects of precipitation and soil moisture on BBD varied among species.(2) The modified models predicted the BBD of herbaceous plants with R~2 ranging from 0.17 to 0.41 and RMSE ranging from 9.03 to 11.97 days, better than classical thermal models.(3) The spatiotemporal pattern of BBD during 1980–2015 showed that species with later BBD, e.g. X. sibiricum(mean: day of year 135.30) exhibited an evidently larger spatial difference in BBD(standard deviation: 13.88 days) than the other species. Our findings suggest that influences of temperature and water conditions need to be considered simultaneously in predicting the phenological response of herbaceous plants to climate change.  相似文献   

7.
Using the Global Energy and Water Cycle Experiment—Asian Monsoon—Tibet Plateau Experiment (GAME-Tibet) observational data—from October 2002 through September 2003—of Gaize in the western Qinghai-Xizang Plateau (QXP), the land-surface characteristics of the Qinghai-Xizang Plateau are simulated by the improved land-surface model Common Land Model (CoLM). The results show that CoLM can reproduce the land-surface characteristics of plateau areas well. In the surface-energy balance of the western QXP in the winter half year, the sensible heat (SH) flux constituted the dominant energy, and the latent heat (LH, here and after) flux is very small. Although the LH flux nearly equals zero in freezing season, it cannot be ignored during the period of freezing–thawing in QXP. In the transition season from mid- to late-May, the frequent phase change of soil water that is caused by the freezing–thawing process leads to the increase of LH flux and decrease of the Bowen ratio. The simulation results also indicate that the changes of surface effective heat fluxes (SH and LH flux) are associated with precipitation and the frequent change between freezing and thawing processes in soil surface.  相似文献   

8.
土壤地理     
S153.62006010241三峡库区土壤中硒、碘、氟分布特征与规律研究=The distri-bution characteristics of Se,I,Fin soils in the district of ThreeGorges Reservoir/唐将,李勇…∥长江流域资源与环境.—2005,14(4).—491~495表5参16(宋金叶)HNS15,X1442006010242冻融条件下土壤  相似文献   

9.
Air pollution is a serious problem brought by the rapid urbanization and economic development in China, imposing great challenges and threats to population health and the sustainability of the society. Based on the real-time air quality monitoring data obtained for each Chinese city from 2013 to 2014, the spatiotemporal characteristics of air pollution are analyzed using various exploratory spatial data analysis tools. With spatial econometric models, this paper further quantifies the influences of socioeconomic factors on air quality at both the national and regional scales. The results are as follows:(1) From 2013 to 2014, the percentage of days compliance of urban air quality increased but air pollution deteriorated and the worsening situation in regions with poor air quality became more obvious.(2) Changes of air quality show a clear temporal coupling with regional socioeconomic activities, basically "relatively poor at daytime and relatively good at night".(3) Urban air pollution shows a spatial pattern of "heavy in the east and light in the west, and heavy in the north and light in the south".(4) The overall extent and distribution of regional urban air pollution have clearly different characteristics. The formation and evolution of regional air pollution can be basically induced as "the pollution of key cities is aggravated—pollution of those cities spreads— regional overall pollution is aggravated—the key cities lead in pollution governance—regional pollution joint prevention and control is implemented—regional overall pollution is reduced".(5) At the national level, energy consumption, industrialization and technological progress are the major factors in the worsening of urban air quality, economic development is a significant driver for the improvement of that quality.(6) Influenced by resources, environment and the development stage, the socioeconomic factors had strongly variable impacts on air quality, in both direction and intensity in different regions. Based on the conclusion, the regional differentiation and development idea of the relationship between economic development and environmental changes in China are discussed.  相似文献   

10.
The use of continuum regression(CR)for the identification of finite impulse response(FIR)dynamicmodels is investigated.CR encompasses the methods of principal component regression(PCR),partialleast squares(PLS)and multiple linear regression(MLR).PCR and MLR are at the two extremes of thecontinuum.In PCR and PLS,cross-validation is used to determine the optimum number of factors or‘latent variables’to retain in the regression model.CR allows one to vary the method in addition.Cross-validation then determines both the optimum method and the number of latent variables.The CR‘prediction error surface’—a function of the method and number of latent variables—is elucidated.Theoptimal model is defined as the minimum of this surface.Among the cases studied,the optimal modelusually comes from the region of the continuum between PCR and PLS.Few derive from the regionbetween PLS and MLR.It is also demonstrated that FIR models identified by CR have frequency domainproperties similar to those identified by PCR.  相似文献   

11.
海洋水文     
P7312006010080粤西水东单点系泊海域潮流和低频流特征=The character-istics of low frequency currents in the area of Shuidong an-chored floating whelf in the west of Guangdong coastal waters/严金辉,陈达森∥海洋湖沼通报.—2005(3).—8~15图4表2参6(许桂红)NX8242006010081长江口及其邻近海域悬浮物浓度和浊度的对应关系=Cor-responding relationship betweensuspended matter concentrationand turbidity on Changjiang estuary and adjacent sea area/翟世奎,张怀静…∥环境科学学报.—2005,25(5).—693~699根据该次调查…  相似文献   

12.
The paper presents a procedure to obtain response surfaces with non-designed data.The method is basedon PLS modelling of the expanded X-matrix followed by transformation of the PLS loadings intopolynomial coefficients and detection of the co-ordinates of the best response within the experimentaldomain.The results are presented both graphically and numerically.The procedure is validated on anoptimization study of the yield of an organic reaction.  相似文献   

13.
The Institute of Geographic Sciences and Natural Resources Research (IGSNRR),Chinese Academy of Sciences (CAS) was established in 1999 through a merger of two former CAS institutes:The Institute of Geography (IOG) and The Commission for Integrated Survey of Natural Resources (CISNAR).The former was established in 1940 and the latter in 1956.  相似文献   

14.
医学地理     
X1412006010866贵州碘缺乏病区生态地质环境特征=The characteristics ofeco-geological environment of iodine deficiency disease inGuizhou/廖莉萍,廖桂香…∥吉林大学学报.地球科学版.—2005,35(1).—104~108为了探讨贵州碘缺乏病与生态环境关系,对贵州碘缺乏病区岩石、土  相似文献   

15.
<正>The Institute of Geographic Sciences and Natural Resources Research(IGSNRR), Chinese Academy of Sciences (CAS) was established in 1999 through a merger of two former CAS institutes:The Institute of Geography (IOG) and The Commission for Integrated Survey of Natural Resources (CISNAR).The former was established in 1940 and the latter in 1956.Both institutes had a long history of distinguished engagement in and contribution to the development of geography and natural resources  相似文献   

16.
<正>The modern geopolitical situation clearly demonstrates the development of two opposite directions.The first one includes the formation of a common global space,which unites the interests of individual countries that have similar political goals.The formation of the military alliance of NATO and countries of the European Union that seek to dominate in the world politics is a remarkable example of such  相似文献   

17.
The 5th International Symposium on the Tibetan Plateau/The 24th Himalaya - Karakorum-Tibet Workshop Joint Conference was held on August 11-14 in Beijing, China. The Joint Conference was hosted by Chinese Academy of Sciences (CAS), The Ministry of Land and Resources of China (MLR) and People's Government of the Tibet Autonomous Region (TAR). Organized by Institute of Tibetan Plateau Research, CAS (ITPCAS), Institute of Geology, Chinese Academy of Geological Sciences (IGCAGS), The China Society on Tibetan Plateau (CSTP), Department of Science and Technology, TAR, Institute of Geographic Sciences and Natural Resources Research, CAS (IGSNRR), International Centre for Integrated Mountain Development (ICIMOD).  相似文献   

18.
生物与土壤     
S154.42006032259森林凋落物-土壤动物-土壤系统中营养元素含量关系及分异=The relation and difference of nutritional elements inforest litter-macrofaunas-soil system/殷秀琴,邱丽丽…∥地理研究.—2006,25(2).—320~326在较缓的丘陵坡面上,6中营养元素的纵向分异并不十  相似文献   

19.
自然保护     
Q959.82007010824基于层次分析法的秦岭地区大熊猫栖息地质量评价=The quality evaluation of giant panda’s habitat based on analytic hierarchy process/李军锋,李天文…∥山地学报.—2005,23(6).—694~701栖息地是大熊猫存在与否的决定因素,栖息地保护的重要性远比对大熊  相似文献   

20.
区域规划     
F061.52007043667地域主体功能区划理论与方法的初步研究=The theoriesand methods of major functionregionalization/朱传耿,仇方道…∥地理科学.—2007,27(2).—136~141在对地域主体功能区划的理论依据与原则等进行深入分析的基础上,提出通过生态敏感性等级分区与经济社会发  相似文献   

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