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1.
I INTRODUCTIONNatllral environment and water transform in theworld have changed faster and faster under the effect ofhuman activities. The study on effect of human activities to hydrological processes, and its extent and tendency has been more and more important as one of theresearch projects of hydrology in the world (RAI et al.,1998, BASS et al., 1998, WANGet al.,, 1998; HILLet al., 1998; LIU, 1997). It became one of the mainresearch program of international Hydrological Decade(… 相似文献
2.
陈百明 《中国地理科学(英文版)》1997,(1)
I.MR.BROWN'SMAINOPINIONMr.LesterBrown,'presidentoftheWorldWatchinstituteintheU.S.A,publishedalongicicletitledas"WhowillfeedChina"in1994(Brown,1995),whicharousedgreatresponSeSfromhomeandabroadandattractedmuchattentionfromallsides.Theadnideasofthearticleincludethefollowingthreepoints:(1)ItisestimatedthatthepopulationofChinawillincrare490whitionfrom1990tO2030,uptol,600whition;thecultivatedlandofChinaisaffectedbythemedeAnzationoftheeconomy,andisevendisap~ng;inaddition,thepotentiality… 相似文献
3.
The South China Sea water can be divided according to depth into three boxes by the pycnoclineand a sill.Using a box model with matter balance,the net seawater fluxes were calculated to be317.9×10~4 m~3/s in box Ⅰ for the upper homogeneous layer outflowing to the adjoining oceans;67×10~4 m~3/s in box Ⅲ for the water entering the basin;240×10~4 m~3/s in box Ⅱ for water entering theSouth China Sea.The upward speed of basin water was calculated to be 8.4×10~(-5) cm/s and that ofseawater flowing up along the pycnocline was calculated to be 8.9×10~(-5) cm/s. 相似文献
4.
STUDY OF WATER—TRANSPORT THROUGH SOME MAIN STRAITS IN THE EAST CHINA SEA AND SOUTH CHINA SEA 总被引：7，自引：0，他引：7
OCCAM global ocean model results were applied to calculate the monthly water transport through 7 straits around the East China Sea(ECS)and the South china Sea(SCS).Analysis of the features of velocity profiles and their variations in the Togara Strait,Luzon Strait and Eastern Taiwan Strait showed that;1)the velocity profiles had striped pattern in the Eastern Taiwan Strait,where monthly flux varied from 22.4 to 28.1 Sv and annual mean was about 25.8 Sv;2)the profiles of velocity in the Togara Strait were characterized by core structure,and monthly flux varied from 23.3 to 31.4 Sv,with annual mean of about 27.9 Sv;3)water flowed from the SCS to the ECS in the Taiwan Strait,with maximum flux of 3.1 Sv in July and minimum of 0.9 Sv in November;4)the flux in the Tsushima Strait varied by only about 0.4 Sv by season and its annual mean was about 2.3 Sv;5)Kuroshio water flowed into the SCS in the Luzon Strait throughout the year and the velocity profiles were characterized by multi-core structure.The flux in the Luzon Strait was minimun in June(about 2.4 Sv)and maximum in February(about 9.0 Sv),and its annual mean was 4.8 Sv;6)the monthly flux in the Mindoro Strait was maximum in December(3.0 Sv)and minimum in June(Only 0.1 Sv),and its annual mean was 1.3 Sv;7)Karimata Strait water flowed into the SCS from May to August,with maximum in-flow flux of about 0.75 Sv in June and flowed out from September to April at maximum outflow flux of 3.9 Sv in January.The annual mean flux was about 1.35 Sv. 相似文献
5.
GlObalwa-rmingisoneoftheseriousenvironmentproblemswhichattractattentionsofscientistsandgove~entsofvariouscountries.TheglobalatmOSpherecomponentschangebecauseofhtirnanactivitiesandthedevelopmentofindustry.Theincreaseofgreenhouseeffectleadstoglobalw~ng.Basedonthepredictionofgeneralcirculationmodel(GCM),bythemiddleofnextcentury,theconcentrationofopwillbedoubledandtheglobaltemperaturewillinCreasebyZt(Han,1993;She~,1983).WestudiedthelawofvegetationalterationunderthisconditioninnortheastChinain… 相似文献
6.
A collection of brachiopods by the Institute of Oceanology . Academia Sinica (Qingdao ). contains eight species from seven genera. Six of the species have been recorded previously from Chinaseas -- Lingula adamsi . L. anatina, Discinisca Stella. Pelagodiscus allanticus, Campages mariae,Terebratalia coreanica . Two species (Terebratulina hataiana and Frenulina sanguinolenta)have been described from other parts of the Pacific area . The apparent absence of any endemic species is a noteworthy feature of Chinese in comparison with Japanese faunas . 相似文献
7.
YU Tao-fang 《中国地理科学(英文版)》2006,16(1):1-8
1INTRODUCTIONAs significant economic motors and political actors, the global cityregions have been regarded as crucial parts of development strategies in China. In the "Eleventh Five- year Plan" by the National Development and Reform Commission of P. R. China, the Beijing-Tianjin-Hebei Province (Jing-Jin-Ji) region, one of the typical mega- lopolises or global cityregions in the East Coastal China will be paid much more attention in the future (GU and YU,2002;YAO,2005;MAO,2005)… 相似文献
8.
This paper introduces the experiences and models of land resources use in China. They are: (1) to protect farmland is as the basic state policy; (2) to carry out land resources survey and land use planning; (3) establishing a resource-saving agricultural production system with land saving as its priority; (4) to develop agriculture in the whole territory and explore food resources; (5) improving eco-environment and protecting land resources; (6) population control'and moderate consumption to release the pressure on land resources; (7) the integrated development and experiment of the typical regions. 相似文献
9.
The seawater complexation capacity for heavy metals (copper, lead and cadmium )in the South China Sea was determined by anodic voltammetry and the conditional stability constants of these complexes were calculated. The data showed that the complexation capacity of the South China Sea water was greater than that of seawater in the Huanghe Estuary and the coast water of Qingdao. The sequence of complexation capacity is C(CuL)>C(PbL)>C(CdL), and the conditional stability constants were in an opposite sequence: K.(CuL) Cd and Pb were similan to those obtained by Buckley (1986) for the Atlantic Ocean water. Complexation capacity is maximum at the surface layer, decreasing with depth, reaching minimum at 750m, but increasing again near the sea bottom. 相似文献
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11.
Nearshore sea levels in the East China Sea(ECS) and the South China Sea(SCS) during tropical cyclones-Typhoon 8007(Joe, 1980) and Typhoon 7209(Betty 1972) were simulated. The tide-surge interactions in the two regions are remarkable and locally produced. The corresponding nonlinear effects were derived from the different nonlinear terms. The contribution of the quadratic friction term is the most important, the shallow term comes second the convective term is the least; the phases of the interactions generated by the various nonlinear terms are asynchronous. Both the quadratic friction and the convective term can stimulate and aggravate the surge structure with more peaks. The bottom friction features have crucial influences on tides and surges, and the interaction is sensitive to the changes of tide and surge. 相似文献
12.
肖笃宁 《中国地理科学(英文版)》1992,2(1):18-29
Alfisols are important soils in China. They occupy about 1.25 million km3, or about 13% of the land area. In the current Chinese system of soil classification, burozem, yellow-brown earths, Baijiang (Planosol) soils and parts of drab soils. They are mostly forested soils with an estimated 5-13 t / ha · yr of organic matter returned to the soils from temperate mixed conifer and broad-leaved forest. In terms of elemental bio-cycling, Ca is prominent.In a comparison of 30 profiles the average ratio of clay (B/ A) was 1.47 for Cryoboralfs and Eutroboralfs; 1.88 for Hapludaifs and 2.53 for Paleudalfs. From Eutroboralfs to Paleudalfs the average gain (or loss) in clay during soil development is about a factor of seven.The moisture regimes vary considerably between Hapludaifs, Cryoboralfs, and associated Cryaquepts, but the amount of water is always enough to cause significant leaching. In the weathering, and pedogenesis processes TiO2, MgO and Fe2O3 are accumulated, respectively, in both A and BA horizons; b 相似文献
13.
The following six aspects in the utilization of lake resources and progress of limnological research in China are described : 1 . Expeditions for comprehensive investigation of lakes ; 2 . Physical limnology; 3 . Lacustrine sedimentology and paleolimnology ; 4 . Hydrobiology and ecology ; 5 . Hydrochemistry and environmental protection; 6 . Development and utilization of lake resources. 相似文献
14.
SNOW HAZARD REGIONALIZATION IN CHINA 总被引：1，自引：1，他引：0
For the zoning of snow hazard in China, on the principles of (a) comprehensive analysis integrated with dominant factors, (b) multi-level division, and (c) serving the agriculture and stock-raising, transportation and communication, we first classified China into two large zones according to the situation of snow or no snow distribution. Secondly, based on the climate and landform, properties of snow cover and main features of snow hazard, the large zone of snow hazard can be classified into three second-level regions. In order to obviously reflect the difference of snow cover quantity and snow hazard type as well as hazardous degree, twenty subregions (third-level) of snow hazard are further divided in detail. In addition, the boundaries and the principal features of the differences between the various snow hazard regions are provided. 相似文献
15.
The ciliate community in the Bohai Sea (China) was studied from 23 September to 7 October 1998. A hurricane struck the study area between the two grid station investigations, which were six days apart. Six tintinnid species ( Favella panamensis, Leptotintinnus nordqvisti, Tintinnopsis but-schlii, T. karajacensis , T. Radix and Wangiella dicollaria ) were identified. Total cililate abundance in the surface layer ranged from 20 to 770 ind/l. In the first grid investigation, Tintinnopsis karajacensis dominated in the warm, low salinity waters at the Huanghe River mouth. Aloricate ciliate sp. 1 dominated in the cold, high salinity waters in the northwest of the study area and the Bohai Strait. In the second grid investigation, T. Karajacensis almost disappeared. The abundance of aloricate ciliate sp. 1 decreased drastically. The aloricate ciliate sp. 2 dominated at the Bohai Strait. The change of ciliate abundance may be due to the disturbance of hurricane. 相似文献
16.
Commercial economic region (CER), or commercial geographical region, is the result of socialized production and development of commodity economy, characterized by system holisty, regional independence, interregional openness and relative steadiness. Commercial economic regionalization provides a scientific basis for organizing and building a commodity circulation network system with all directions, multifunction and openness, rational planning the direction of commodity flow. The principles of commercial economic regionalization are as follows: The principle taking a city business center as the core; the optimization principle of integrated function; the difference principle of physical geographical environment; the uniformity principle of human geographical environment; and the order principle of dissipative structure. According to the above-mentioned principles, China's CER can be divided into 4 1evels. 相似文献
17.
COASTAL SALT MARSHES AND MANGROVE SWAMPS IN CHINA 总被引：6，自引：0，他引：6
Based on plant specimen data,sediment samples,photos,and sketches from 45 coastal cross-sections,and materials from two recent countrywide comprehensive investigations on Chinese coasts and is-lands,this paper deals with China’s vegetative tidal-flats:salt marshes and mangrove swamps.Thereare now 141700 acres of salt marshes and 51000 acres of mangrove swamps which together cover about30% of the mud-coast area of the country and distribute between 18°N(Southem Hainan Island)and41°N(Liaodong Bay).Over the past 45 years.about 1750000 acres of salt marshes and 49400 acres ofmangrove swamps have been reclaimed.The2.0×10~9 tons of fine sediments input by rivers into the Chinese seas form extensive tidal flats,the soil basis of coastal helophytes.Different climates result inthe diversity of vegetation.The 3～8m tidal range favors intertidal zone development.Of over 20plant species in the salt marshes,native Suaeda salsa,Phragmites australis,Aeluropus littoralis,Zoysiamaerostachys,Imperata cylindrica and in 相似文献
18.
1 IntroductionTomonitorthecurrentcrustalmotionandearthquakehazardsinNorthChinaarea,theFirstCrustalMonitoringandApplicationCenter (FC MAC)oftheChinaEarthquakeAdministration(CEA)hasestablishedaGlobalPositioningSystem(GPS)monitoringnetworkinNorthChinaandtheCapital(Beijing)Circlearea .TheobservedstationsaremainlydistributedinthenorthernpartofNorthChinaandCapitalCirclearea (Fig .1 ) .Theregionisbetween 1 0 7°Eand 1 2 2°E (about 1 40 0km) ,andbetween 33°Nand 42°N (about 80 0km) .… 相似文献
19.
王明远 《中国地理科学(英文版)》1993,3(4):376-380
We have made progress in medico-chemical geography as follows: the correlative law of organism with geochemical environment; the geochemico-ecological classification of chemical elements; the types of formative cause of biogeochemical provinces in China; the parabolic correlation between contents of iodine in drinking water and prevalence rate of endemic goiter; the discovery and proof of the low selenium zone in China; the successive discovery of endemic fluorosis of the types of pollution from burning coal, drinking high fluoride tea and high fluoride table salt from the year 1978; the study on chemical geography of schistosomiasis and the compilation of the Atlas of Endemic Diseases and Their Environments in the People's Republic of China. 相似文献