From the study of landform,stratum,spore-pollen、fossil,ancient culture sites,tectonism,sea-level change and so on,the environmental change of Taiwan since late Pleistocene is analysed in this peper.In late Pleistocene or before,the environmental chafe of Taiwan was affected chiefly by tectonism and sea-level change during glacial and interglacial stages.In Holocene,however,it was affected chiefly by climate and sea-level changes.The environment of Taiwan in early Holocene was similar to that in late glacial stage,but the temperature had gone up again.The environment of Taiwan was tropical environment in middle and late Holocene with some fluctuation.
Genesis of drainage and forming mechanism of granite seem to be absolutely different problems,however,it is discovered that the larger rivers always avoid the late Mesozoic granite bodies,while most of the smaller ones often run through the bodies in the lower Pearl River System.It is very difficult to explain the phenomenon by the opinions of either lithologic differences,fault controls or modem topography,while"sins the theory of remelting of granite formation,the problems can be readily solved.According to the theory,with the rise of the ancient geothermal gradient in late Mesozoic caused by the intense collision between Eurasian Plate and Pacific Plate,partial remelting in layer,thining as well as folding under the lateral strong compression occurred in the upper crust,as a result,the granitic magma should be squeezed upward to the relative low pressure area in the top portion of anticlines,meaning that the large number of the granite theies in the same period are only the doming portions of the same remelting layer.So the ancient rivers of that time in the lower Pearl River System certainly run in low areas avoiding the relative higher dome mountains (became granite bodies after stripped),and this regimen has been inherited until nowadays though many of them had not been connected and had not become external rivers (they just ran into the nearby basins) until ligocene,which is real cause of the phenomenon.The relationship betWeen the large rivers and fate Mesozoic granite theies are not only found in the researched area,but abc in other areas that contain late Mesozoic (or early Tertiary) granite both in China and abroad,suggesting that the aSes of the rivers in those areas may be older than late Tertiary and that remelting mechanism has been the most important forming way of granite since Mesozoic.
According to the hierarchic system of integrated physicogeographical regionalization in physical of China edited by Chinese Academy of Sciences(1985),the 5 grading units from high to low are great nature area,nature area,nature region,nature sub-region and nature minor-region.The Nansha Islands is in the South China Sea Tropical Islands Evergreen Forest Nature Region (the third grade region),which belongs to the South China Tropical Humid Area (second grade region) in the Eastern Monsoon Area (first grade region).Nansha Islands area may also be divided into 2 regions of fourth grade and 4 regions of fifth grade.The two nature subregions (fourth grade region)are:I1 The Equatorial Shelf Shallow Sea and Coral Reef Nature Subregion in South Nansha Islands.I2 The Tropical Deep Sea and Limesand Islet Evergreen Forest Naturesub-region in North Nansha Islands.The four natural minor-regions (fifth grade region) are I1-1 The Coral Reef Region in South Nansha Islands.I1-2 The Equatorial Shelf Shallow Sea Region in South Nansha Islands.I2-1 The Limesand Islet Evergreen Forest Region in North Nansha Islands.I2-2 The Tropical Deep Sea Region in North Nansha Islands.A map of physicogeographical regionalization of the Nansha Islands is drawn.The principal characters of the nature sub-regions and nature minor-regions are described.And the vertical zonality from surface to bottom in deep sea is preliminarily discussed.
The effects of three types of vegetation which are barren land,eucalyptus and broad-leaf mixed forest on soil are compared.The researched site is located at a tract of seriously eroded terrace land in Xiaoliang,Dianbai County,Guangdong (110°54'E,21°27'N),where the annual mean rainfall is about 1700mm and temperature 23℃,the soil is laterite.The result shows that the nutrient content within plant depends mainly upon its own physiological features,with no direct relation to nutrient supply by soil.Vesetation helps the accumulation of some elements in soil,or help to increase the element availability.Long term leacbog of soil das not shake the hots for srowing plant.The soil havins been seriously eroded conjoins normal quantity of mineral nutrient as the zonal soil.Different vegetation cover has different impact on soil.Soil on barren land is in degradation,where the poor properties impair the development of vegetation.Pure eucalyptus forest growing on bare hod does not improve the soil significantly.It even forms a crust on land surface to lessen the infiltration of rainfall.However,eucalyptus forest protested through human interference helps to increase the content of organic matter,totul nitrogen and available phosphorus of the soil.The broad leaf mixed forest is the best type of vegetation for soil improvement.
Based on the monthly mean data,the characteristics of 3~5 year period of air temperature in Hubei Province and its association with 3~5 year low-frequency variation of the 500hpa height field in the Northern Hemisphere are analysed.It is shown that the 3~5 year period fluctuation of interannual temperature variation is significant,and is related to 3~5 year fluctuation of N.H.500hPa circulation.The relationship between the two 3~5 year period components is closer than that between the two total amounts.It is also found the relationship between the interannual low-frequency variations of the temperature and teleconnections of the atmosphere is clear,particularly for the relationship between the air temperature in January and PNA anomaly.The correlation analysis betWeen the PNA index in Januny and the 3~5 year SST fluctuation over the northern Pacific shows that the SST anomaly can result in the anomalious PNA pattern of circulation over the Pacific-North America 3~4 months later,which causes the air temperature anomaly in January over Hubei.
In this paper,the 1956～1990 rainfall data of May for 26 representative stations in Yunnan are analyzed by using EOF method.Distribution feature and distribution types of rain in for since 1956 are investigated.The results show that the time coefficient of the first three characteristic fields in May in Yunnan is of remote correlation with the SST of tropic Pacific during the same period.If an EL Nino phenomenon occurs,rainfall in May in Yunnan will be less,and if an negative EL Nino phenomenon occurs,that will be more.
In this paper,the laws of temporal and spatial distribution,the physical mechanism of formation and dissipation,and the micrortructure of the radiation fog in Jinghong,Xishuangbanna are studied.The results show that; 1) the radiation fog is the most in fog season,and in January it is formed the earliest and dissipated the latest,with the longest sustained time;2) the fog is formed firstly at the layer between 50m to 100m above ground level,then the top of the layer can rise to the height of 300m;3) the formation of the fog is mainly caused by the radiative cooling of the earth surface and the atmosphere,and its dissipation is due to the heating of the ground by solar radiation and the turbulent tranSport of heat to the atmosphere.
Numerical simulations of climatic change resulted from deforestation in the Amazon Basin were made abroad.It is predicted that if the Amazon Basin were denuded of forest,climate there would become more drought and hot because of the weakenness of the hydrological cycle.The precipitation would decrease by 20% and evapotranspiration by 30%,while the surface temperature increase by 2.0-3.0℃.Moreover,if the basin became desert like North Africa,the precipitation would be reduced by 60 percent.
Based on the meteorological data in GuangZhou from 1951 to 1990,the climatological survey of the urban co temperature(≥35.0℃) and its cause in Guangzhou are analysed in this paper.The countermeasures to relieve the urban high temperature are also put forward.There were 238 high temperatUre days in the past 41 years;or 5.8 days a year on average,in Guangzhou.The high temperature appears mainly on July and August.The maximan temperature is 38.7℃.The rank of high temperature is usually between 35.0℃ and 36.9℃.The high temperature days annually are generally from 5 to 7,but the longest was 32 days (in 1990).The lougest countinuous period of high temperature lasted 11 days (in 1990).The high temperature in Summer in Guangzhou is caused by the combination of the urban heat island effect and the restonal high temperature background.The regional high temperature occurs under the influence of typhoons and subtropical high pressures.The urban heat island effect aggravates the high temperature.In the urban heat island,the temperature can be raised by 3.9-4.7℃ in some cases,but normally about 1.0℃.In order to weaken the intensity of the urban heat island and to relieve the high temperature,an effective way is to strenthen the work of afforestation in urban area,in addition to reasonal urban planning to reduce the amount of the anthropogenetic heat,so as to make the working and living environment better for people.
Since the reform and opening to the outside world,GuangZhou has developed rapidly,and industry has hems moved from urban centte to suburb,which is called industrial suburbanization.In this paper,the development of industry and its internal structure adjustment,the rapid development of the tertiary industry,the high density of population and lack of land for construction,and the requirement of environmental protection in urban center,etc.F which are the main causes of industrial suburbanization,are discussed.Some suggestions.about the regulation of industrial suburbanization are put forward:1) to choose a proper orientation of industrial suburbanization,developing new industrial areas and industrial towns ;2) to study the law of urban land location and interests;3) to make appropriate policies for the move of industry from the urban center;and 4) to approve living conditions of the new industrial areas.
The base of sustained socio-economic development is the sustainable utilization of land resources,for which the key link is to protect cultivated land and to keep up the ecological balance of natUral environment.Guangzhou City is not only the capital of Guangdong Province,but also an administrative with widespread agricultural hinterland,so it is very important to protect its cultivated land and natural environment.Because of the increase of the population in the city,and the rapid development of towns and industry,environmental pollution is becoming more serious.For the sustainable utilization of land resources,the following measures are suggested:1)make a scientific overall land-use plan,2) correct the deviations in city planning so as to efficiently protect the cultivated land,3) improve the system of administration and supervision land,4) set up a reasonable structure of land-use,5) strengthen the management and construction of environment,6) set up a system of natural ecological environment protection with land protection aS its key link,and 7) exploit positively reserved land resources.
The economic benifits of the industries in Guangdong are studied by factorical analysis and cluster analysis.Eighteen industries are classified into 4 types,and their advantages and disadvantages are evaluated.1) The development of type Ⅰ is accelerated by the growing market demand,but the cost of production is not saved.2) Tin Ⅱ shows good prospects of low cost,high profit and quick fund turnover,but labour productivity is not satisfactory.3) Type Ⅲ is profitable,but the high cost,inflexible fund turnover and low labour productivity restrict the raise of the economic beninfits.4) The economic benifits of Type Type fall into deep valley because of low labour productivity,low profit and high cost.To achieve better economic benofits,some suggestions are put forward as follows:1) make proper industry policy and organization policy according to the relation between industrial economic benifits and its influence coefficient 2) pay attention to the industry link chain while supporting the leading industries.3) strengthen the management of industrial macrosmicture,and reduce the cost and increase the output of the enterprises.
Since the reform of economic system and opening to the outside world,the information service sector in Guangzhou City has developed rapidly.It is necessary to do wide and deep researches on its developerment and tendency so as to provide a theoretical base for further study.During the period since the reform,the great changes and rising trend in the channels of information sources,relative significance of these channels,technological efficiency of information collection and processing,quality of information products,and scale,ways and process of information diffusion of Guangzhou Daily,could be identified.Furthermore,the spatial pattern of the information product diffusion of Guangzhou Daily has been characterized by the acceleration of diffusion speed,expantion of spatial scope,relative centralizaton and absolute decentralization of distribution pattern,with the improvements of regional traffic conditions,residents'incomes and educational level,and informational product quality.The theoretical significance of this case study is that a comprehensive and concrete analysis,which focuses on the processes of information collection,processing and diffusion implemented by a typical enterprise for information dissemination in a central city,will be helpful to the understanding of temporal and spatial processes of information in the central city,remedy the defects of some researches at the macro level,and provide a bee for further study.
The Five-Finger Crags tourism area lies in Chagan Town,in the north of Pingyuan County of Guangdong Province.It is a typical Danxia landform scenic spot with distinctive local style,which is characterized by a) pricipitous finger-shaped hills,b) big and deep rifts in the rocks,c) hazy and changeable views,and d) marvelous and beautiful natural landscape.The tourism area can be divided into six scenic spots:Five-Finger Crags tourism comprehensive development spot,Xihai stone-forest viewing spot,Yazizai mountain-climbing,exploring and hunting spot,fortified mountain village scenic spot,Yunzhuanshi scenic-touring spot;and Taipingding ecoagriculture viewing spot.For the development of the area,some measures are suggested:1)making a good image design for the tourism area as a whole.2) Dealing correctly with the relation between the exploitation of the,central part and that of other oarts in the area.3) Solving the problems of tourism traffic and water supply.4) Developing a series of tourism products to meet the demands of the tourism market.
As the fourth dimension of geography discipline,the time quality has historical geography stay in the center of time-space study on modern geography,and promotes the development of the discipline synthetically.There are three couples of opposing time concepts in the reality:1.the steady calendar time and the lasting real time;2.the historical tine recorded only in the document and the whole time of human history;3.the only historical time of the "past" and the united historical time of "past","current" and "future".The time concept of study on historical geography is certainly the concept of the lasting real time,the whole time of human history,and the united historical time of "past","current" and "future".The study on geographiCal environment should be done in its lasting course by means of different time systems and time scales.The former or later positions of the factors of geographical system on the time dimension,combined with the sires and directions in the geographical areal become the massive complex system of geographical realities.
