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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CHEN Bai ming, ZHANG Feng rong
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    Developing indicator system of sustainability for land resources is one of the superiority fields of study of science and technology put forward in Agenda 21st for each country.The Ministry of Land and Resources has started to deal with this project.The paper probes into the theory and methodology for developing the indicator system of sustainable land use in China.It firstly reviews the domestic and overseas evolvement in the study on sustainable land use,then analyzes and summarizes the current conditions and experience about indicator system for sustainable land use in foreign countries.It points out that three aspects must be taken into consideration to researches of the indicator system for sustainable land use.They are:1)to divide land use regions and establish territorial indicator system for sustainable land use;2)to classify main land use systems and set up their indicators and threshold for sustainable land use;3)to select indicator system and threshold of sustainable land use in typical areas for case study.Only to integrate the three aspects organically can the scientific meaning,systemalization and practicability be assured.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CHEN Fu, CHEN Gang, BAO Hao sheng, PENG Bu zhuo
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    Based on remote sensing images in 1988,1993 and 1998,measurement of Mashans land use was conducted through methods of maximum like and probabilistic relaxation,which revealed the city's spatial process in the past 11 years.The conclusions may be distinguished as follows:(a) The results of the detection are reasonable and it is feasible to calculate the transfer matrix of land use to show spatial pattern of land use distribution as unit of image pixel.(b) The main characteristics of Mashans land use change are the obvious reduction of the existing farm land and forest land,and subsequent rapid increase in urban land along Guzhu road and tourism/vocationing district along ring road which are the main developing axes during the recent 10 years.In 1988,agricultural production was the main human driving force that impacted Mashan landscape,but in 1998,urban development became the main one.The typical agricultural landscape in 1988 has been transformed into the urban fringe landscape in 1998.(c) Under the favorable policy formulated by the central and local governments,the main driving forces of land use change in Mashan are the rapid growth of population,foreign investment,fixed assets investment and development of the tertiary industry which was based on tourist industry.The driving forces will continue to affect land use in the future.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    GONG Dao yi, SHI Pei jun
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    The high variability of summer rainfall over northern China has great impacts on environmental and socio economic system.In this manuscript,the decadal variability is analyzed.Power spectral analysis indicates a 35 yr period dominated by low frequent variations exists.The locations of 250 mm isohyet also show great annual variations and dramatic decadal changes.The averaged latitudinal location before and after 1978 changed about 1.5 degrees.The relationship between summer rainfall over northern China and spring surface temperature over vast expanse is investigated.There are two regions found connecting to summer rainfall significantly,one is India,Pakistan and their adjacent ocean sectors where positive correlation occurs,and the other is over inner continent in central and West Asia where negative relationships exist.The spring temperature of these two regions can explain 15% of the difference in summer rainfall in northern China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Hong
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    Responses of NPP of salinized meadow in hyper arid area to global change were predicted using the NPP model,developed by the author to simulate the NPP of natural salinized meadow in northern part of Tarim Basin.The result shows that the NPP of salinized meadow in hyper arid area is the function of underground water table(UWT) and the temperature in given soil conditions.The NPP of salinized meadow decreased with increase of underground water table.Responses of NPP to change of UWT and temperature increase resulting from global change vary with different UWT of salinized meadow in hyper arid area.The impacts of global change to NPP of salinized meadow,therefore,depend on differing UWT of salinized meadow.It is extrapolated that responses of NPP of salinized meadow to global change are more sensitive with greater UWT than those with shallower UWT.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    DENG Guo, WANG Ang sheng, LI Shi kui, ZHOU Yu shu
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    Risk analysis theory mainly refers to use scientific methods to reduce losses resulting from all kinds of uncertainties to the minimum through differentiation, estimation and disposal. Based on the theory, this article discusses the risk problems in grain yield. Given a grain yield sequence, firstly we decompose it into two main parts according to different factors that affect yield. Secondly we translate the two parts into a ratio sequence, through which we could get rid of the influence of dimension as well as productivity, and the sequence reflects the information of fluctuation of grain yield during recent years. In addition, we form a function to simulate the rate sequence and subsequently calculate the probability of a cerain risk level of the sequence using the method of integral. This kind of information conduces to disaster management as well as formulation of proper policies in disaster reduction.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WU Guo qing
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    Resources and environment are the key part and base for regional agricultural sustainable development.Ecological safety for agricultural and rural development means that resources and environment on which agricultural and rural development depend are balance,and agro ecosystem is health.There are many characteristics on ecological safety,such as strategy,integrity,regionality,hierarchicity,dynamic and periodicity.As a case study of Jiaxing city,Zhejiang province,the paper discusses the method and process of evaluation of ecological safety on agricultural sustainable development,and identifies an indicator system of ecological safety that has 23 indicators group on resource ecology environment pressure,quality and protection ability.Mathematics model on indicators calculation is set up.Indicator standards on ecological safety are given.The approach to and strategy for constructing ecological safety on agricultural sustainable development are pointed out by taking Jiaxing city as a case in this article as well.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LI Bao lin,, ZHOU Cheng hu
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    West sandy land of Northeast China Plain lies in the eastern fringe of huge sandy belt of middle latitude in Eurasia Continent which is also the eastern fringe of desertified land with best bio climatic conditions in China.With the development of economy and the deterioration of eco environment,desertified landscape becomes increasingly obvious and is very anxious for us.Climatic factor is a fundamental factor for desertification development,the climate in west sandy land of Northeast China Plain is the best among the sandy lands in northern China.So far no systematic research work on climatic change and desertification has been carried out in this region.This paper analyzes the modern climatic features that affect desertification in west sandy land of Northeast China Plain,explores the relations between climatic variations,human activities and desertification,and predicts the possible trend of desertification under the effect of natural factors according to climate development trend in the future, providing the basis for desertification control.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Jian dong, ZHOU Xiu ji, YU Qiang
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    A combined model was established for simulating canopy photosynthesis based on the data observed with portable Licor 6200 photosyntometer. The architecture of crop canopy was fully considered in the model,and the model can simulate instantaneous photosynthesis.Results of the validation of the model by the observation data measured with GHX 305 CO2 analyzer showed that the model can simulate photosynthesis rate of crops in field fairly well.Results of the simulation of the totals of daily CO2 assimilation with the model showed that greater deviations existed in the basic parameters of FAO productivity model.The basic parameters in FAO productivity model were reconstructed in this paper,which will provide theoretical basis for estimating crop productivity more accurately.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Shu hua, MAO Han ying
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    In recent years,eastern China has made great progress in economy. But with its rapid development,man land conflicts have become more and more serious. This paper,based on the review land carrying capacity,constructs a set of indicator system for comprehensive evaluation of regional land carrying capacity that can be adapted to eastern China. More over,by the use of a certain mathematical method,we can divide this region into three types according to the carrying capacity: the lower level carrying capacity subregion;the mid level carrying capacity subregion;and the higher level carrying capacity subregion. All these types stand for three steps of succession to the land carrying capacity,that is,from the harmonious step at lower level,imbalance step at middle level to the harmonious step of the advanced system.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    HE Chun yang, CHEN Jin, CHEN Yun hao, SHI Pei jun
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    In the current land use/cover change detection,post classification is often used for its little limitation to radiometric correction.However,as the error in the individual date classification map will also be present in the final change detection map and usually causing the fault of the change detection,a new change detection method combining Change Vector Analysis (CVA) and Post classification is thus given in this paper.From the result of the case study in Haidian District of Beijing,one can see that the error in post classification was reduced greatly and the relatively reliable land use/cover change information was also obtained,although the shortcoming of error accumulation can not be solved entirely.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHOU Bin, YANG bai lin
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    The land use changes in Anshun City,Guizhou Province from 1987 to 1995 were detected by using direct classification of stacked multitemporal TM images. Compared with other methods,such as postclassification comparison and pixel to pixel comparison methods,the change detection algorithm used herein can not only bypass the illogical error,but also obtain the “from to” information directly.The results showed the difference or ratio bands had poor classification accuracy(overall accuracy equal approximately to 30%~40%),while those bands could well inherited the original ones achieved better accuracy(overall accuracy>70%).In addition,the different radiometric rectification methods could affect the accuracy of change detection to a large degree,the preliminary research indicated that the dark set bright set method might improve the accuracy by 16.6% in comparison with the histogram algorithm.Also,our results indicated that the study area had experienced some notable land use changes during 8 years,such as urban expansion,cultivated land encroachment and spatial change of vegetable land.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Xi qin
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    The decision making model of water environmental protection and economic development was proposed by means of modularization design idea.This model mainly consists of water demand module,water environmental capacity module,macro economy module,water pollution control module and economic structure optimization module.With a multilevel model,by solving equations representing each of these components,the rational economic structures and appropriate development speed,which either accord with economic development aim or meet water environmental protection needs,were achieved.It provides a trajectory and method for the study of water environmental protection and economic development.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Xin hua, BI Jian tao
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    In this paper we develop a classification model on coal resources with the method of fuzzy clustering neural networks by combining Adaptive Resonace Theory with Error Back Propagation which can calculate the fuzzy questions,and is more adaptable to the needs of resources evalution.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Wan jun, GUO Yu wen, WANG Dou tian, HANG Ming yong, ZHANG Min sheng, MA Jia yong
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    Aiming at the status qua of the shortage of soils suitable for landscaping construction in TEDA,the demands for sustainable development of the environmental construction and the existence of large quantities of three solid wastes (ooze,alkaline slag, coal ash) in coastal zone of Tianjin,their physical and chemical properties were studied in detail. Based upon which,the feasibilities of replacing earth brought in from elsewhere with the wastes are discussed. The results of experiments and popularization demonstrated that they could be developed into a new type of soil and substitute the earth brought in from elsewhere. They also showed that the most feasible proportion of mixing sea silt to alkaline slag or coal ash is 3:1,and besides,which is superior to sea shore saline soil in plant growth.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WENG De bao, HUANG Xue fang, YANG Ji lou
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    Four kinds of traditional wild vegetables have been cultivated and utilized in Nanjing.Taking the egg protein as standard protein and WHO/FAO reference model of essential amino acid(EAA) as an appraisal criterion and putting 6 kinds of vegetables as a series of contrast, the authors evaluated the protein nutritional values of these cultivated wild vegetables in Nanjing by using the method of fuzzy discrimination and the method of ratio coefficient of amino acid(AA) respectively.The results showed that the protein contents of these wild vegetables ranged from 2.3%~5.0%.These gross proteins were rich in all kinds of AA which accounted for 77.73%~89.36%.EAA took up 36.72%~42.04% of total AA.The first limiting AA was sulfur containing AA, Met and Cys.The protein quality of these cultivated wild vegetables was far superior to that of some common vegetables belonging to the same family respectively.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Meng heng, RU Jiang, SONG Xiao zhi
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    Along with the increasing awareness of global environmental problems,develo ping countries will ratify more and more international environmental conventions to participate in the international cooperation of environmental protection.Though most conventions clearly state that the parties of developed countries shall offer enough fund and necessary technologies to the parties of developing countries to help them implement their commitment,yet there are still obstacles to technology transfer.This paper discusses the impediments in the implementation of international environmental conventions and studies the real problems developing countries are facing.Chinas experiences in the implementation of Montreal Protocol on Substances that Deplet the Ozone Layer are analyzed as a case study.The reasons for the existing impediments and their potential impacts are presented.Finally,the suggested strategies for developing countries in the implementation of international conventions are proposed.