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This is a brief report of a preliminary survey of certain rain-bearing systems over China in later spring and summer. In the first part, a general description of the methods of analysis used in this survey is given. As the temperature and wind fields are weak, and the precipitation is heavy, smaller intervals for the isotherms and contours in the constant pressure surface and pseudo-equivalent potential instead of potential temperature in the cross section analysis are used.In the second part, there are descriptions...

This is a brief report of a preliminary survey of certain rain-bearing systems over China in later spring and summer. In the first part, a general description of the methods of analysis used in this survey is given. As the temperature and wind fields are weak, and the precipitation is heavy, smaller intervals for the isotherms and contours in the constant pressure surface and pseudo-equivalent potential instead of potential temperature in the cross section analysis are used.In the second part, there are descriptions of the structure and development of five frequently observed rain-bearing systems i.e. cold front, blocking high and cold vortex, monsoon heat low, warm front and typhoon.The last part consists of discussions of some points of view in synoptic meteorology in China. It is stated that the monsoon precipitation is various in intensity and duration according the large-scale flow patterns. The difference of moisture content in the middle troposphere as a criterion for the identification of equatorial or tropical maritime air mass is proved to be missleading. It is shown that the upper air moist content is high only within the raining region near the polar or equatorial front. To the south of the equatorial front within the so-called equatorial air mass, the moist content in the middle troposphere is as low as within the tropical maritime air mass. It is the convergence and lifting of the tropical air mass which releases the convective instability and induces the surface moist air rising to the middle troposphere. The phenomenon of the forward-inclination of the so-called North-West Trough based on the time cross-section of wind is proved to be a mistake by combining two systems into one trough. The terminology of shear line, and the correct application of synoptic models in weather analysis and forecas-ting are also discussed.

本文是一年来从事夏季降水天气初步普查的简单报告。第一节首先指出所用分析方法与一般国内所通用者,稍有不同。高空等压面分析,取20米作为等高缐间隔,2℃作为等温缐间隔。代替40米及5℃的间隔,以适应夏半年较弱的温度场与气压形势场,在剖面分析中以等假相当位温缐代替位温缐,与等温缐配合以适应降水天气的凝结降水过程。 第二节讨论了五种夏半年基本降水天气系统,即冷锋、阻塞高压与冷涡、季风热低压、 暖锋及有风的结构,并简单地叙述了演变过程。 第三节对某些天气概念提供一些批判性的讨论。根据现已增加的观测材料,论证季风与梅雨是多样性的,决定于大规模的温度场与流场特性,以高空湿度大小区分赤道气团与热带海洋气团,证明是不适当的,因为中国赤道锋降水区域以南,即在所谓南南季风的赤道气团中,中层大气仍是干燥的。降水区域内,中层对流层的大量水份,是由于辐合或抬升的作用,使潜势的对流不稳定性成为现实的不稳定性,而由下层空气上升带上去的。文中还论证了所谓西北槽槽缐前倾是将两个系统混作—个系统的不正确桔果。最后还讨论了切交缐及一般模型在天气分析预报中的应用与限制。

This paper deals with ecology and part of the Life history of the Chinese alligator. In making the investigation, the auther has paid visits to the Lower Yangtze basin and its adjacent territory during February-October in 1951, 1954, and 1956 in south Anhwei.The Chinese alligator inhabits the alluvial plain. During the growth and development of river, there are two seasonal periods in a year. The rainy season covering from April to October, and the dry season from October to March of the next year. During...

This paper deals with ecology and part of the Life history of the Chinese alligator. In making the investigation, the auther has paid visits to the Lower Yangtze basin and its adjacent territory during February-October in 1951, 1954, and 1956 in south Anhwei.The Chinese alligator inhabits the alluvial plain. During the growth and development of river, there are two seasonal periods in a year. The rainy season covering from April to October, and the dry season from October to March of the next year. During the dry season, one side of a broad sand swamp is an artifial dam, while the opposite is the natural bank, which may be gradually destroyed by the current in the rainy season year after year.During the rainy season, the water level is higher which serve as a shelter to the hidden alligator.The Chinese alligator is not only found along the basin of the lower Yangtze River, but also in south Anhwei districts along Chin-I-Kiang and Cheun-Ho River system. The plain is always sunk down by the tide, its surface being usually covered by a harder mud. A lot of burrows are distributed here and there. Each burrow has seveal holes. It is seaier to find out such burrows in the fall and winter, because the reeds are then cropped.Investigations showed that there were two types of burrows with respect to the sex of the alligator found inside. The male burrow is a simple tunnel with two openings, while the female's is more complicated.A longitudinal section of the female's burrow shows that the burrow is somewhat like a three-storied building. The differences in the level of diggings are considered as adaptations to different water levels.The following table presents burrow types in sexual diamorphism.The changes of water levels of the alluvial plain of definite regional river system may be related, according to our field examination, to the period of the animal's hibernation. The burrowed creature is coiled underground in 2m. deep during the winter season. The types of the burrows may be shown in the following table:In the wet season, the water level is about 8m. deep, just reaching.the surface of plain. This fact indicates that water is essential to the animal in the regulation of its physiological processes.The alligator mates in May and June, nesting at the end of June, laying The words "Doors'' and "Windows" adopted here are taken to indicate the various openings of the nests of the alligators.eggs in the July and August. The eggs measure 59 mm. in diameter. The shell is very hard, being ashy white in colour.The head and body length of the breeding adults as well as the number of eggs found in females may be given in following table:Other observations on the night movement during the breeding period may be shown as follows:

1.我国古代早在商周时期,即对此项动物加以记载,下至晋唐,都曾有记述,包括分布、形态和生态诸方面。综合辨考前人记载鼍及其近种的分布,是在今日的湖北、山西、广西、广东、安徽、福建、江苏、江西和当时邻国柬埔寨等地。 2.动物的栖息地为河流、湖泊、丘陵山涧的河漫滩的芦苇及竹林丛中。调查地包括了安徽省、江西省沿江的河漫滩及属於黄山天目山的青弋江、渲河、青山河的下游和芜湖、南陵、宣城、泾县、当涂、高淳、宁国、郎溪诸县。时间是1951年,1954年,1956年2—10月间。 3.据据39尾鼍的标本测定,其雌雄的外形性徵差异不显著,但其所营穴窟却有显著的两性相异形式。二者均包括有洞身和各种不同的洞口,适於进出、呼吸等用。 4.雌性个体异穴分居。 5.动物每年4月初开始出洞活动,6月间配偶,7月初至8月中旬筑巢产卵,在在6—8月间最为活动,10月下旬开始入蛰休眠。 6.动物在竹林芦苇田中筑巢,取材枯叶、杂草、乾枯稻草和菱白叶。体长92.1厘米者,巢中的卵数20。卵长59毫米,径34毫米,围110毫米,卵重43克,壳重3.75克。 7.动物昼伏夜出,风雨之夜概不出洞。最热季节,日中当大气气温31—35℃、湿度40—48°时,曝...

1.我国古代早在商周时期,即对此项动物加以记载,下至晋唐,都曾有记述,包括分布、形态和生态诸方面。综合辨考前人记载鼍及其近种的分布,是在今日的湖北、山西、广西、广东、安徽、福建、江苏、江西和当时邻国柬埔寨等地。 2.动物的栖息地为河流、湖泊、丘陵山涧的河漫滩的芦苇及竹林丛中。调查地包括了安徽省、江西省沿江的河漫滩及属於黄山天目山的青弋江、渲河、青山河的下游和芜湖、南陵、宣城、泾县、当涂、高淳、宁国、郎溪诸县。时间是1951年,1954年,1956年2—10月间。 3.据据39尾鼍的标本测定,其雌雄的外形性徵差异不显著,但其所营穴窟却有显著的两性相异形式。二者均包括有洞身和各种不同的洞口,适於进出、呼吸等用。 4.雌性个体异穴分居。 5.动物每年4月初开始出洞活动,6月间配偶,7月初至8月中旬筑巢产卵,在在6—8月间最为活动,10月下旬开始入蛰休眠。 6.动物在竹林芦苇田中筑巢,取材枯叶、杂草、乾枯稻草和菱白叶。体长92.1厘米者,巢中的卵数20。卵长59毫米,径34毫米,围110毫米,卵重43克,壳重3.75克。 7.动物昼伏夜出,风雨之夜概不出洞。最热季节,日中当大气气温31—35℃、湿度40—48°时,曝晒於水面。

The city of Lanehow lies in the central part of China in latitude approximate 36°03′north, longitude 103°57'east, at elevation 1,508.53 M. Kowlanshan, the area surveyed, being one of the many loess plateau hills surrounding Lanchow, situates on the southeastern suburb of the city. Physiographically, the area is a part of the dissected loess plateau with an altitude of 1,508-2100 M. Owing to the influences of the geographical condition and high elevation, the climate of this area is of continental climatic type....

The city of Lanehow lies in the central part of China in latitude approximate 36°03′north, longitude 103°57'east, at elevation 1,508.53 M. Kowlanshan, the area surveyed, being one of the many loess plateau hills surrounding Lanchow, situates on the southeastern suburb of the city. Physiographically, the area is a part of the dissected loess plateau with an altitude of 1,508-2100 M. Owing to the influences of the geographical condition and high elevation, the climate of this area is of continental climatic type. The mean annual precipitation is 338.6mm. with 61.1% of it falling in June, July and August, annual mean temperature, 6.9℃., relative humidity, 58%, annual total evaporation, 3,571mm. and annual mean wind velocity 5.8m/sec. The upper portion of the hill is entirely covered with a thick layer of loess and underneath lies the red earth of the tertiary period. As a result of that, soils in the area surveyed, which has been developed from the loess, is high in calcium content. It belongs to the chestnut soil type with a PH value between 7.6 and 8.1. The vegetation of this area shows the following ecological characteristics: 1) The specific composition of the plant is rather scanty with about. 124 speeies belonging to 93 genera and 41 families; 2) The vegetation bears a simple physiognomy. No natural growth arbor been found in the whole area during the period of investigation, though a few species of cultivated trees are found and the vegetation is mainly composed of semi-frutexes and herbages; 3) Most of the essential species distributing here express distinct xeromorphic structures and many of them are typical components of the vegetation of the steppe and semi-dessect, such as Caragana spp., Hololachne soongarica Ehrenb., Artemisia spp., Chrysanthemum neofruticulosum Ledeb., Stipa spp. Achnatherum splendens Ohwi. and so on. Four plant associations are found in this area. Three of them distribute on the Dorthern slope and one on the southern slope of the hill. They are described as follow: Ⅰ. Chenupodium album+Artemisia annua+Elymus dasystachys Association. The distribution of this association is limited to the erosion valleys situating on the piedmont belt of the northern slope at an elevation between 1, 510 and 1, 560 M., where the edaphic condition is marked by high soil moisture content. The climatic features are of low light intencity with short duration of daily sunshine, high relative humidity and low wind velocity. Three hygrophilous and shade-loving species are the main constituents of this association. They are chenopodium album L., Artemisia annua L., and Elymus dasystachys Trin. Other herbaceous plants are Chenopodium glaucum L.. Sonchus aler- aceus L., Xanthium strumarium L., Polygonum amphibium L., P. aviculare L. etc. A few shrubs are present in the association. They are Lycium chinensis Mill., Lonicera heteroloba Batal. and Lonicera ferdinandi Fr. Ⅱ. Artemisia pectinata Association. The Artemisia pectinata Association occurs on the piedmont belt of the northern slope at an elevation varying from 1510 to 1580 M. It occupies the open slope with gradients under 15°. The climatic conditions, in speaking of the northern slope, are rather high in temperature, strong light intencity, low relative humidity and low wind velocity. The projective total cover-degree is about 50% and Artemisia pectinata Pall. appears to be the dominant species in the association. Besides, there are species of thermophilous and heliophilous plants such as Salsola kali L., S. arachnoides‘Moq’. Kung, Cymbaria mongolica Maxim., Artemisia capillaris Thumb., Aster altaicus willd., chrysanthemum neofruticulosum Ledeb., which are frequently scattered among the dominant plants. Plants growing in this association, are all below 10 cm. in height. They give an appearence of open association. Ⅲ. Chrysanthemum neofruticulosum+Artemisia sacrorum var. latiloba—Polytrichum sp. Association. This association, being the largest one in the surveyed area, appears on the northern slope, where it occupies the space ranging from altitude 1,580M. to the top of the hill,2,100M, above the sea level. Soil is of chestnut soil type with a PH value of 8. 0—8. 1.The soil moisture content varies between 6.0 and 7.4%(layer above 60 cm.). In vertical structure, the association consists of two strata. They are described below: Stratum Ⅰ: This stratum includes all shrubs, semi-frutexes and herbages which are taller than 10 cm. in height. Among the plants found in this stratum, chrysanthemum neofruticulosum Ledeb. and Artemisia sacrorum var. latiloba Ledeb. are dominant species and Stipa Bungeana Trin. is the subdominant one. Other species one may frequently meet with are Allium subangulatum Rag., Saussurea nigrescens Maxim., Peganumharmala L., Astragalus dahuricus Dc., Potentilla multifida L., Linum perenne L., Car-agana frutex K. Koch. etc. They spread widely in almost all over the association. Stratum Ⅱ: This stratum is composed of those species less than 10 cm. in height, forming the ground flora of the association. Polytrichum sp. and Lichens are the essential plants in the stratum. One may occasionlly find species of Plantago Lessingii and Gentiana squarrosa Ledeb. growing among those main constituents. The underground stratification of the association has also been studied during the time of surveying. IV. Stipa Bungeana+Aster altaicus+Chrysanthemum neofruticulosum Association. This association distributes on the entire southern slope except the portions tilled for agriculture purposes. The striking local ecological conditions of this association are strong light intensity with long duration of daily sunshine, high temperature, low relative humidity and extremely low in soil moisture content which ranges between 2. 7 and 4. 0% (the layer above 60cm.). On account of the severe destruction of natural vegetation by man and cattle in the past years, the degree of soil erosion is serious throughout the slope where the association locates. The PH value of the soils is 7.4-76. The polydominant plants in this association are Stipa Bungeana Trin., Aster altaicus Willd. and Chrysanthemum neofruticulosum Ledeb. They are quite adaptable to the drought condition of the environment and distribute widely in the association. Besides, other xerophilous or drought resistant plants are frequently met, such as Hololachne soongarica Ehrenb., Linum perenne L., Astranalus dahuricus Dc., Peganum harmala L., Artemisia sacrorum var. latiloba Ledeb., Artemisia capillaris Thumb., Incarvillea Iutea Bur.&Franch., Kochia scoparia Schred. etc. They dispersely grow in the association. In addition to the frequent species mentioned above, Salsola ruthenica Iljin. and S. arachnoides‘Moq’. Kung form seperately micro-associations lying scatterly on the slope. No ground flora stratum may be found and the association shows no above ground stratification. The projective total cover-degree of this association is only about 25-30%. Owing to the difference in the aspects of the northern and sourthern slopes, the climatic and edaphic conditions vary remarkable. Therefore, the vegetation of the surveyed area shows distinctions in distribution, floristic composition, physiognomy, structure, condition in growth and development of plants in the association of different slopes. Taking the floristic composition for example, the following species are entirely absent in the association of the northern slope, yet they are main components on the southern one: Pappophorum brachystachyum Taub. et Spach, Thermopsis lanceolata R. Br., Caragana spinosa Dc., Stellera chamaejasme L., Hololachne soongarica Ehrenb., Nitraria schoberi L., Pennisetum flaccidum Griseb. Differences in elevation also induce striking changes in climatic and edaphic con-ditions especially in aspects of air temperature, relative humidity and soil moisture content. All these gives great influence to the alterations either in quantity or in quality of each species distributing along the northern slope of the area. Following the seasonal change, the physiognomy of the associations expresses sucession of seasonal aspect. Vernal, aestival and autumnal aspects have been observed and recorded.

兰州位于我国的中心,约占北纬36度03分,东经103度57分,拔海1508.53米。皋兰山是兰州四周环山中的最高峰,位居兰州市东南郊。在地形上,皋兰山属于分割黄土高原山岭的一部分,拔海高度约为2100米。由于地理位置及海拔的影响,兰州的气候属大陆性气候类型。年平均温度为6.9℃,年平均雨量为338.6毫米,而61.61%集中在6、7、8、三个月,全年各月平均相对湿度为58%,年蒸发量则达3,571毫米,风力为5.8米/秒。皋兰山山岭的顶部均为厚层的黄土所掩盖,其下则为第三纪红土层。因此,调查区的土壤,全由黄土母质发育而来,含多量钙质,属栗钙土类,PH值为7.6—8.1。调查区的植被,有如下的生志特点:(1)植物种属比较贫乏:全区植物只有41科,93属,124种;(2)群落外貌单纯:调查区内缺乏自然生长的乔木,植被主要由半灌木与草本植物所构成,属干燥草原区的灌木草本群落型;(3)植物具明显旱生形态:群落主要成分,很多是干燥草原区的代表种属,如锦鸡儿属、蒿属、菊属的小黄菊(Chrysanthemum neofruticulosum Ledeb.)、羽茅属、芨芨草等。它们都具有各种适应干旱环境的形态特征。调查区植物...

兰州位于我国的中心,约占北纬36度03分,东经103度57分,拔海1508.53米。皋兰山是兰州四周环山中的最高峰,位居兰州市东南郊。在地形上,皋兰山属于分割黄土高原山岭的一部分,拔海高度约为2100米。由于地理位置及海拔的影响,兰州的气候属大陆性气候类型。年平均温度为6.9℃,年平均雨量为338.6毫米,而61.61%集中在6、7、8、三个月,全年各月平均相对湿度为58%,年蒸发量则达3,571毫米,风力为5.8米/秒。皋兰山山岭的顶部均为厚层的黄土所掩盖,其下则为第三纪红土层。因此,调查区的土壤,全由黄土母质发育而来,含多量钙质,属栗钙土类,PH值为7.6—8.1。调查区的植被,有如下的生志特点:(1)植物种属比较贫乏:全区植物只有41科,93属,124种;(2)群落外貌单纯:调查区内缺乏自然生长的乔木,植被主要由半灌木与草本植物所构成,属干燥草原区的灌木草本群落型;(3)植物具明显旱生形态:群落主要成分,很多是干燥草原区的代表种属,如锦鸡儿属、蒿属、菊属的小黄菊(Chrysanthemum neofruticulosum Ledeb.)、羽茅属、芨芨草等。它们都具有各种适应干旱环境的形态特征。调查区植物群落,可区分为下列的四个群丛: 1.白药+黄花蒿+厚穗滨草群丛(Chenopodium album+Artemisia annus+Elymus dasystachys Association) 本群丛分布于皋兰山山麓的侵蚀沟谷内,约占海拔1510至1560米的地段。所在地气候与土壤特点是光线弱、日照时间短、风力小、大气相对湿度大与土壤潮湿。群丛优势种有白藜、黄花蒿和厚穂滨草三种喜湿耐阴植物。此外,伴生有灰绿藜、苦苣菜、苍耳、两栖蓼、扁蓄等草本植物。灌木则可见枸杞(Lycuim chinensis Mill)、紫金银花(Lonicera heteroloba Batal.)、裴氏金银花(L.ferdinandi.Fr.)三种。 2.篦叶蒿群丛(Artemisia pectinata Association) 这一群丛占据皋兰山北坡山麓海拔1510—1580米,坡度在15°以下的开旷地段。其环境条件,在北坡来说,主要表现于阳光充沛,温度高,大气相对湿度低与土壤干燥。群丛总夏盖度约为50%,而以篦叶蒿最占优势。常见植物有钾猪毛菜、灰蓬(Salsola arachnoides‘moq’Kung)、蒙古芯芭(Cymbaria mongolica Maxim.)、茵陈蒿、阿尔泰紫菀、小黄菊等喜光喜温种类。 3.小黄菊+供蒿-藓群丛(Chrysanthemum neofruticulosum+Artemisia sacrorum var latiloba-Polytrichum sp. Association) 本群丛包括皋兰山北坡自海拔1580米以上一直至山顶(海拔2100米)的全部地段,为调查区内分布面积最广的群丛。其生态环境是阳光弱、日照时间短、蒸发量小、气温低;土镶为栗钙土,PH值在8.0—8.1左右,土壤风干含水量为5.2—5.6%。群丛在垂直结构上,可分为两层:第一层包括高度在10厘米以上的灌木、半灌木与草本植物,而以小黄菊和供蒿最占优势。本氏羽茅则为本属中的亚优势种。常见植物尚有野葱、青木香(Saussurea nigrescens Maxim.)、骆驼蓬、达乌里紫云英,多裂委陵菜、宿根亚麻、木锦鸡儿(Caragana frutex K. Koch.)等。第二层为地被层,主要由藓类和地衣所组成。此外,偶尔出现细叶车前(Plantago Lessingii)与鳞叶龙胆(Gentiana squarrosa Ledeb.)铺地生长。群丛总复盖度约为67%。 4.本氏羽茅+阿尔泰紫菀+小黄菊群丛(Stipa Bungeana+Aster altaicus+Chrysanthemum neofruticulosum Association) 这一群丛占皋兰山南坡除农田以外的全部地区。其气候与土壤条件,可归纳为下:日晒强烈、日照时间长、气温高;人为对自然植被破坏强烈,表土冲刷现象异常严重。土壤水分含量甚低,仅占风干重的1.88—3.41%,pH值为7.4—7.6。本氏羽茅、阿尔泰紫菀与小黄菊为群丛中的主要种类。它们对于干旱的环境均具有强大的适应力。其他常见植物有红砂、宿根亚麻、达乌里紫云英、骆驼蓬、供蒿、茵陈蒿、黄角蒿(Incarvillea lutea Bur.&Franch.)地肤等抗旱或耐旱种类。苏联猪毛菜(Salsola rutheniea Iljin)和灰蓬,常各成单纯小群丛,出现于山坡间。本群丛中缺地被层,无地上成层现象。群丛总复盖度仅为25—30%。由于南北坡取向不同所引起气候与土壤因子的变化,调查区植物群落,在分布、结构、外貌、种类成分及生长发育状况上,也随着发生很大的差异。海拔高度的改变,对气温、相对湿度,土温及土壤水分状况的影晌,也明显地反映在群落中各个种间的数量比例关系上。随着季节的更换,群落中的种类成分,表现出比较显著的季相演替关系。作者等曾作北坡群丛春、夏和秋三季季相的观察与纪录。

 
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