Archive

  • Select all
    |
    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Hong yu, LU Xian guo, LIU Zhen qian
    Download PDF ( )   Knowledge map   Save
    With a large area, various types and complex landscape structure, wetlands in the Liaohe and Huanghe Deltas have substantially benefitted the regional economic development. Based on the classification system of wetlands, the present situation and distribution characteristics are studied through RS and GIS techniques. At present, there are 314,857 ha of wetlands in Liaohe Delta,accounting for 79.5% of the total urban area; among which there are 159,919 ha of natural wetlands and 154,838 ha of artificial wetlands, accounting for 50.8% and 49.2% of the total wetland area, respectively. In Huanghe Delta,the total wetland area is 333,427 ha,being 42.7% of the total urban area; and there are a natural wetland area of 229,329 ha,and artificial wetland area of 104,098 ha,accounting for 68.78% and 31.6% of the total wetland area, respectively. Because of the regional resources exploitation for many years, wetlands have changed a great deal both in area and structure. Some strategies concerning protection of ecological function of wetlands and solution to the problems of the sustainable development between resources exploitation and wetland protection are put forward in this paper.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CUI Bao shan, LIU Xing tu
    Download PDF ( )   Knowledge map   Save
    With over half century reclamation,great changes have taken place in ecological features of wetlands in Naolihe Drainage Basin.The paper analyses the main changes,including change in wetlands,change in water condition and water quality,all related to non sustainable exploitation of wetlands.Reclaiming and destorying wetland resources has led to a series of ecological problems,such as serious soil erosion,increase in local desertification area and water erosion,only the emphasis on use without measures of protection,the divorce between reclamation and construction,resultins in decline of soil fertilities to different degrees and the intensification of environmental pollution as well as biodiversity decreasing.Naolihe Drainage Basin is an important part of Sanjiang Plain,wetland changes will seriously affect the sustainable development of Sanjiang Plain.So,as the new policy comes with the advent of the new century,Naolihe Drainage Basin will get the best period of regulation.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Yao guang
    Download PDF ( )   Knowledge map   Save
    The Liaohe Delta is one of the four great deltas in China,namely,the Changjiang Delta,the Huanghe Delta,the Zhujiang Delta and the Liaohe Delta.The core position of the Liaohe Delta is located in Panjin City,Liaoning Provines.It is rich in natural resources,such as flat land resources,petroleum and natural gas resources buried underground and a vast area of reed,wetland and tideland.There are many favorable conditions for developing industry and agriculture in Liaohe Delta.To utilize the land resources fully and reasonably,the characteristics of the present structures in land utilization of the Liaohe Delta are analyzed.Some parameters concer ning land utilization structures are investigated on the spot.The optimization model of the reasonable structure in land utilization is identified by applying the linear programming method .In the optimization model,a linear inequality is built with many variables such as the areas of paddy field,dry land,reed,oilfield,salt pan and shrimp pond.And the objective function and the restrained conditions in the near future and in the long run are set out.By means of calculating optimization,the optimum composition of current land utilization in the near future and in the long run is obtained for the region of the Liaohe Delta.The values of the objective function are obtained from the optimum structure in land utilization in different period times.At the end of the paper,twelve countermeasures are put forward to realize the optimization of the land utilization structure and the sustainable land utilization of the Liaohe Delta.And the steps which ought to be taken for each countermeasure are also put forward.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YANG Gui shan
    Download PDF ( )   Knowledge map   Save
    The Yangtze River Delta is one of the regions with most densely population,fastest economic growth and most intensive land use,the contradiction of land shortage sharpened by high speed economic development has become the problem not to be ignored which restricts regional sustainable development This paper has revealed the characteristics of high intensity land exploitation and the basic process and driving forces of change in arable land area according to the data of long series statistics of arable land area during the past 50 years and detailed investigation of land use during the recent five years The research results show that there is a trend of obvious fluctuant decrease in arable land area during the past 50 years.The changes of arable land area undergo the process from increase to steep decrease to gently decrease to rapid decrease,in which,there are three height periods of decrease in arable land,they are 1958 to 1963,round about 1985 and round about 1993 respectively The mechanism of decrease in arable land are mainly the driving forces of policy,economic development and population growth
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    XU Yue tong, FENG Hai xia, WU Yuan fang, LI Hong mei, ZHOU Chen, LI Fu lin
    Download PDF ( )   Knowledge map   Save
    The 185.1 km long section of the Yellow River locating in Jinan City covers a drainage area of 2,778 km2. Both interannual and intra annual water discharge of the Yellow River in Jinan varies greatly.The maximum quantity of runoff is 21.8 times as the minimum one.The runoff concentrates in flood season during the months of July to October,representing 60.7% of the annual value averaged on many years.In recent years,the runoff quantity of the Yellow River in Jinan shows a decreasing tendency year by year and the state of breaching of has been intensified.In 1997,the Yellow River ran dry for 132 days at the Luokou hydrological station.At the same time,the sediment content of the Yellow River in Jinan is high,averaging 24.9 kg/ m3 over years,showing an increasing trend.In recent years the quantity of water from the upper reaches has been decreased and the water using quantity has been increased.The water resources have been seriously wasted.The water has been polluted to some degrees.The regular capacity of reservoir is low,the water resources have not been dispatched and administered in a sustainable way.All these mentioned above have hindered sustained utilization of the Yellow River in Jinan section.The article,based on the analysis of existing status of water resources and the main problems in resources exploitation and utilization,on the prediction of water delivery and water demand,addresses the main countermeasures to the sustained utilization of the Yellow River water resources in Jinan section.(a)Taking sustained strategy as a principle,making overall planning and administering as a whole and making centralized dispatch.(b)Extending the present reservoirs and building new ones.Making full use of these water conservancy projects to ensure the water used in ecology.(c)Combined utilization of surface water and groundwater resources.(d)Building a water saving production system and society,improving effective utilization rate of water resources.(e)Adjusting price of water according to economic leverage.Promoting water saving awaveness and implementing water saving measures.(f)Reinforcing the dikes of the Yellow River and planting trees to control sand and prevent flood and ice dam,for the sake of achieving regional sustainable development of the Yellow River in Jinan section.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    MA Jin zhu, LI Ji jun
    Download PDF ( )   Knowledge map   Save
    Groundwater has been changing extensively affected by human activities combined with desiccating climate conditions.In modern times,population growth,accompanied by development of industrial and agricultural production and the petroleum exploitation,brought about rapid expansion of artificial oasis with abruptly increasing of water demand.As a consequence,the artificial hydraulic irrigation project took the place of natural river system,the reservoirs took the place of natural lakes which in turn enhanced the space time redistribution of surface water based on natural evolution,and so did groundwater.The groundwater recharge reduced by 26.2% in 46 years from 1950 to 1995 in southern piedmont of the Tarim Basin based on mean yearly population increase rate of 27.7‰ associated with water use rate increasing from 24.6% to 58.4%.At the same time seepage of artificial water system plays a leading role to groundwater recharge,which is up to 57.6% whilst that of the river bed reduce to 33.7%.As a result,groundwater table generally dropped by 3~5 m except some irrigated areas and surroundings of plain reservoirs.Spring water discharge also reduced by about 28.7% and discharge zone continuously moved away to the north with values of 0.5~1.2 kilometers in the past 40a.Meanwhile,groundwater contamination began to rise up quickly,especially in some towns and irrigated areas a lot of organic nutrients such as NH4 N,DOC and SRP were brought to aquifers where groundwater was recharged by surface water.Besides,groundwater evolution has led to serious plant degradation and land desertification.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    FENG Hao, SHAO Ming an, WU Pu te
    Download PDF ( )   Knowledge map   Save
    Based on the situation of serious shortage of water resources and the need of developing eco environment on the Loess Plateau,this paper puts forward theoretical,available and realistic potentials of converting rainwater into resources and discusses the principle and method for calculating the potentials of developing rainwater resources by taking small watershed as research unit and rainwater as research object.A preliminary assessment method for developing rainwater resources is provided combination with 11 small watersheds on the Loess Plateau.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    DONG Yu xiang
    Download PDF ( )   Knowledge map   Save
    Based on the surveying data of land desertification,this paper presents detailed analyses of the types,degrees,area and distribution of land desertification in Tibet,introduces the damages and economic loss caused by desertification and analyses the driving force of the desertification.According to basic line of thinking and strategies for as well as priority field of the large scale development in western China,the project cons truction of land desertification control should be the important construction project of eco environmental protection of Tibet amongst the large scale development project in western regions.The strategy,countermeasures and techniques as well as methods of land desertification control in Tibet are discussed.The basic rules,directions,targets,tasks and important projects of land desertification control in Tibet are analyzed.The main research results are as follows:In Tibet,the area of desertified land is 1,997.40×104ha,being 16.58% of the total land area of the region.There are 3 classes and 5 types of desertified land.The former include serious degree,middle degree and slight degree,making up respectively 1.69%,55.96% and 42.35% of the total desertified area in Tibet.The latter contian shifting dunes land,semi fixed dunes land,bare gravel land,fixed dunes land and semi bare gravel land,covering respectively an area of 33.65×104ha,96.80×104ha,1,021.04×104ha,29.32×104ha and 816.59×104ha.The causes of land desertification in Tibet are the results of comprehensive functions of natural basis,climatic change and human activities.The dry climate,rich land material in soil,high velocity of wind and bare land are accountable for land desertification.The climatic change,reduction of rainfall and rise of temperature expanded the area and intensified the degree of wind drifting sand activities,which led to the natural process of land desertification in Tibet.Meanwhile,the human activities also expanded the area and intensified the degree of wind drifting sand activities,which led to the artificial process of land desertification in Tibet accompanied with rapid human population growth and livestock population increase.With interaction and intensification of natural and artificial processes of land desertification,the desertified area became increasingly enlarged and the degree of desertification became increasingly serious.So,the climatic change and human activities are the main driving forces of land desertification in Tibet.With the origination and development of land desertification in Tibet, serious dama ges have been resulted.The main damages are leading to the deterioration of eco environment and living conditions,destroying construction projects and hindering the economic development,doing great harm to farming and production and living installations,making great economic loss and serious potential pressure.Serious damages made the control of land desertification a very important and urgent construction task in Tibet.According to the basic line of thinking and strategies for as well as priority field of the large scale development in western China,the project construction of land desertification control in Tibet is analyzed.Eight countermeasures,2 ways and 4 kinds of techniques as well as 6 methods for land desertification control in Tibet are given.The rules and basic thinking of project construction of land desertification control in Tibet is discussed.The targets,tasks and important projects of land desertification control in Tibet are analyzed.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Yun fen, OUYANG Hua, CAO Guang min, LUO Ji, ZHANG Xian zhou, ZHAO Xin quan, YANG Qing wei
    Download PDF ( )   Knowledge map   Save
    It is of practical significance and important scientific value to probe into carbonic balance in different ecosystems and its environmental factors affecting it,and to reveal its influence on and response to the changes of global carbonic greenhouse.Experimental studies of soil CO2 emission flux by enclosed chamber technique were conducted at Haibei Frigid Meadow Ecological Station,Gongga Mountain Alpine Forest Ecological Station,and Lhasa Agroecological Station.The diurnal mean value of soil CO2 emission flux was 215.87~329.68 mg CO2m-2h-1 in highland meadows,713.72~2,102.56mgCO2m-2 h-1 in alpine forests,and 913.05~1,135.83mgCO2m-2h-1 in farmlands.Daily change of soil CO2 emission flux showed a single peak in farmlands and growing frigid meadows,both reached the highest at local time of 8∶00 to 16∶00,and the lowest from 0∶00 to 8∶00. In farmland and meadow,soil CO2 emission increased along with the accelerating growth of crops and pasturage.Before closing to the ripening period,the value went down.However in forest area,the highest value of soil CO2 emission reached to a peak from June to September.We found that there was a good correlation between temperature and soil CO2 emission,and temperature appears an important factor affecting soil CO2 emission,so the global warming will very likely increase soil CO2 emission.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LI Jun, , WANG Li xiang, SHAO Ming an, FAN Ting lu
    Download PDF ( )   Knowledge map   Save
    The shortcomings of traditional research method on crop productive potential were analyzed,and advantages of crop growth modeling on the field were proposed.Based on model validation and establishment of weather,soil and crop parameter database,the CERES wheat model of DSSAT3 was used to simulate wheat thermal potential productivity (TPP) and climate potential productivity (CPP) of 28 sites on the Loess Plateau region.The mean yield,yield standard deviation,maximum yield and minimum yield of wheat TPP and CPP were calculated for each site.The annual and locational changes of TPP and CPP were analyzed,and water content ratio (WCR,WCR=CPP/TPP) was calculated.The values of TPP,CPP and WCR of winter wheat on Loess Plateau are 7,970~8,647kg/ha,2,219~7,545kg/ha and 0.278~0.872 separately.And values of TPP,CPP and WCR of spring wheat in the region are 7,436~9,127kg/ha,0~7,598kg/ha and 0.192~0.961 respectively.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Zhi ping, LIU Ai min
    Download PDF ( )   Knowledge map   Save
    This paper applies the research method of model evaluation and optimization and necessary technical system.Agropastoral structure is the main model for agricultural production in piedmont of Taihang Mountains.It can become an optimized model by evaluation and necessary technical system,and can facilitate high efficiency utilization of resources.Alfalfa shows remarkable effects of economy,water and fertility.Farmland subsystem of agropastoral model can save irrigation quota by 35% and possesses remar kable economic and energy efficiencies.Nitrogen and phosphate output/input of alfalfa is much higher than that of wheat maize system and cotton.Some 32.7% of nitrogen and 25.9% of phosphate of animal husbandry subsystem may be returned to the field and finish the definite nutrient cycle.Necessary techniques of optimized model of agropasture are the rational proportion between farming and pasturing,high efficiency management of field,adjustment of husbandry structure,straw fodder treatment,forage planting and agropastoral substance cycle.Among which the rational proportion and adjustment of husbandry structure are the key techniques.Applying rationally theses techniques,comprehensive utilization efficiency of agricultural resources can be added by 20%~30% based on the optimized agropastoral model.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    SHEN Chang Jiang
    Download PDF ( )   Knowledge map   Save
    The author considers that the global problems of resources,especially of the natural resources are serious becoming more and more.One of the important reasons is lack of the holistic concepts and the philosophical ideas of the comprehensive Resources Science.For this reason,modern Resources Science must be developed and constructed,which has dual significance of theory and practice.From this point of view,the author has studied and discussed that what is the Resources Science and what is the disciplinary system of Resources Science.The“three dimensional network structure " disciplinary system has been discussed.The three dimensions are expressed as three parts of Resources Sciencse:General Principles,Individual Resource Branches and Regional Branches,respectively.This multi disciplinary system is a comprehensive disciplinary group of Resources Science,including Natural Resources Science.The knowledge of these disciplines can provide the scientific basis for improvewent of resources management and reform of education for Resources Science.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LUO Jian cheng, ZHOU Cheng hu, YANG Yan
    Download PDF ( )   Knowledge map   Save
    Land cover/land use has become one of the crucial but basic tasks in carrying out a series of important work,such as the prediction of land use change,prevention of natural disasters,management and planning of land use,protection of environment,etc.With the development of remote sensing techniques and Geo analysis model,using remotely sensed data to monitor the status and dynamical change of land cover/land use has become one of the most rapid,credible and effectual approaches.In this article,after we firstly present the RSIGIM model,the intelligent land cover/land use classification framework and system is built up.Based on remote sensing intelligent Geo interpretation model (RSIGIM),the characteristics of traditional RS classification models can be synthetically integrated so that the Geo decision knowledge can be structurally and parametrically fused into.The target aims to build a new systematic structure of land cover/land use classification with the experimental case in Hong Kong,with the support of the data fusion model between the multi platform remotely sensed data and ancillary geographic data.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WEI Wei, QIAN Ying qian, MA Ke ping, PEI Ke quan, SANG Wei guo
    Download PDF ( )   Knowledge map   Save
    The food safety assessment of transgenic organisms has been a world wide concerned issue.Although there are some limitations,the principle of substantial equivalence is widely applied in the assessment of novel food derived from transgenic orga nisms.Many kinds of transgenic food have been assessed,such as potato,soybean,tomato,cotton,rice,squash,tobacco,and asparagus.The methods,principles and results of food safety assessment are discussed in this paper,as well as the potential problems.The progress and problems for the safety assessment of food derived from transgenic organisms are reported in a relatively comprehensive and objective manner.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    MA Zhong yu
    Download PDF ( )   Knowledge map   Save
    Facts of numerous surveys indicate that the location of tourism resources is highly overlapped with poverty stricken areas,it is particularly so for ecotourism resources.Because those areas are always remote and under developed in mass transportation system,and less impacted by human economic activities and cultural intrusion,the natural environments and ethical culture have been kept in a good condition and served as a major tourist feature attracting an increasing number of visitors.Therefore,integrating poverty alleviation activities into the framework of tourism development is one of the most effective ways for alleviating poverty in those areas.However,neither international communities nor Chinese government,have paid enough attention to impacts of tourism development on poverty elimination.The following issues are fully addressed in this paper:(a)Some 592 severely poverty stricken counties in China possess extremely plentiful of tourism resources,where is the major field for implementing the Eight Seven Poverty Alleviation programme by central government.(b)The 592 poverty striken counties are mainly located in the middle and west part of China,where holds the greatest growth potential of Chinas future tourism economy but less potential in agricultural development and fragile environment.The suggestion is made for Chinese central government to take the integration of poverty alleviation with tourism development into the Project of Western Chinas Development.(c)Tourism industry has advantages over other economic sectors in relation to poverty alleviation.(d)It is suggested to build Chinas Pro Poor Tourism Strategy,and the relevant strategic measures at policy and planning framework level for developing pro poor tourism in China are pointed out in order to alleviate poverty in middle and west part of China through tourism development as soon as possible.