摘要
云南高原位于我国西南隅,北与四川西部及西藏东部相连,地势甚高,一般有2,000—3,000米以上,向东向南逐渐降低,但亦在2,000米上下;东面与贵州、广西相连;南部较低,在1,000米上下,与越南、老挝及缅甸接壤,西部与缅甸及印度接壤。境内地形复杂,气候温和。
There are many lakes upon the Yunnan Plateau of South-western China,with an elevation of about 2,000 metres above sea level.They are mostly distributed over the eastern part of the Plateau,surrounding the Kunming region and forming the Kunming lake group,which consists of 7 lakes,namely Kunminghu Lake,Chuhu Lake,Yanglinhu Lake,Yangchunghai Lake,Fusienhu Lake,Singyunhu Lake and Ch’iluhu Lake.All but the last mentioned lake have their maximum-length axes run south and north,thus coincident with the orientation of the orographic foldings of the Yunnan Plateau thrown up during Yanshanian and Himalayan orogensis.In 1957,from July to October,we made a general limnological survey of most lakes of the Kunming lake group,as well as Ilunghu Lake and Dat’unhu Lake to the south and Erhai Lake to the west.The morphometric aspects of the lake basins,the physical and chemical properties of lake waters,and the biological conditions,including phyto-plankton and zoo-plankton,benthos,aquatic vascular plants,fishes and the production of lakes have been investigated.In this paper,only the general features of.the lakes are given.Detailed report for each lake will.be published separately elsewhere.Most of the lakes are shallow,with mean depths less than 15 metres.Yangchunghai Lake is deeper,having a mean depth of 20.27 m and a maximum depth of 28 m.Outstanding among the group is Fusienhu Lake;its mean depth of 88.7 m and maximum depth of 160 m make it the second deepest lake in China,next to Tiench’ih Lake in Kirin Province.The thermoregime of the lake water is very characteristic.The water temperature is higher than 15℃year-round in the lakes of southern part,higher than 10℃in the Kunming Lake group and-in Erhai Lake.During July to October,thermo-stratification is not so conspicuous in the shallow lakes,but is very distinct in those with mean depth over 15m.However,no thermocline has been observed,except for those that temporarily occur at certain period of day time.The transparency of the lake water is less than 200 cm in shallow lakes,but reaches 300-600 and 700-850 cm in Yangchunghai Lake and Fusienhu Lake respectively.The dissolved oxygen content is very high and generally has a stratified distribution.pH values are more than 8.3,since the lakes are mostly localized in limestone region.The hardness of water is extraordinarily high,mostly higher than 60°(German unit),some even as high as 117.23-134.47°(Ilunghu Lake).Therefore it is very clear that the lakes of Yunnan Plateau possess the nature of alkaline water of calcium-type.Dissolved biogenic elements are low in content.The NO_(3)-N is mostly below 0.13 mg/1,PO_(4)-P between 0.012-0.059 mg/1.Erhai Lake and Kunminghu Lake have higher PO_(4)-P concentration,amounting to 0.026-0.217 and 0.09-0.13 mg/1 respectively.The horizontal and vertical distributions of phyto-plankton and zoo-planktons have been studied quantitatively.In some of the lakes,such as Fusienhu Lake and Yangchunghai Lake,diurnal vertical movement of planktons has been observed.Planktons are abundant in shallow lakes,but very poor in deep lakes.The benthos and aquatic plants exhibit the same phenomenon.The fish fauna of these lakes is also very characteristic.A total of 42 species has been collected.The regional distribution is very distinct,especially with reference to the subspecies,of the genus Cypinus and the species of the genus Anabarilius.It is clear that the speciation is closely related to the isolation of the water systems concerned.The natural production of fishes of the lakes is less than 40 kg/hectare.Based upon the results of this investigation,we suggest that the lakes of the Yunnan Plateau may be classified into two types,namely,Eutrophic type of subtropic limestone region in tectonic basin and Oligotrophic type of subtropic limestone region in tectonic basin.Suggestions on fish-management have also been given.
作者
黎尚豪
俞敏娟
李光正
曾继绵
陈嘉佑
高宝云
黄宏金
LEY SHANG-HAO;YU MIEN-KUAN;LI KUANG-CHENG;TSENG CHI-MIEN;CHEN CHIA-YIU;KAO PAO-YUN;HUANG FONG-CHIN(Institute of Hydrobiology,Academia Sinica)
出处
《海洋与湖沼》
1963年第2期87-114,共28页
Oceanologia Et Limnologia Sinica
