甘肃西南之畜牧

民国三十年暑间中华自然科学社,有西北科学考察团之组线,作者承该团之邀,分担畜牧考察,於七月廿六日自蓉出发至绵阳,折川北,越江油,过青川,以达川甘交界之碧口,自此沿白龙江北行,经武都,再循岷江,直趋岷县,过岷县後,溯洮河上游,经临潭,以达韦尼,由卓尼西北行,经旧城,过完科洛,黑错,哈家之草地,以达夏河,更进而至甘青交界之甘坪寺,此为西北大草地之边界,继而折返夏河,向东北行,越临夏而至兰州,搭车过天水,微县,褒城,广元,返归成都,此行往返为时计三月。足迹所至,仅甘肃一隅,可谓仅徘徊於西北之大门,而未入其堂奥,盖受时间经济之限制,致未能窥西北之全豹也。     

大美草原

七月的内蒙古到处是一片绿,绿色的草丛,绿色的树木,绿色的麦田……绿的可爱,绿的温馨。蓝蓝的天空,偶尔有几片白云,在流动,云朵,像雪白的棉花堆一样,时而堆集,时而分散,看上去是那样的悠闲,那样的自然,真让人陶醉。进入了丘陵地带,这里有村庄、有麦田,还有黄黄的油菜地,一条一条地分散在绿色的田野里,远远地看上去真是美极了。草原的路是笔直的,视线很好,一眼顺路望的很远。路的两旁大多都是草原,部分草原上近年来有些沙化,一丛一丛的野苜蓿,顽强地在那守护着,在沙化严重的地带里显得尤     

Urban vacant land in growing urbanization:An international review

Urban growth and shrinkage constitute the overall pattern of growing urbanization across the globe.Studies on urban vacant land(UVL)are few,and have proved to be mainly rudimentary and subjective.This paper first presents the definition of UVL based on bibliometric analysis.Typology,morphology,proximate causes,and the multiple functions of UVL are then analyzed at parcel,transect,city,and national levels based on an international review.Results show that UVL can be categorized by land cover,land usage,and land ownership.Worldwide,UVL has been widespread and extensive.For example,the occurrence probabilities of UVL in the cases of Guangzhou and New York are 8.46%-8.88%and 3.17%-5.08%,respectively.The average vacancy rate of residential land amounts to 11.48%in 65 U.S.cities.Generally,UVL shows fragmentation and irregular shape,and significant spatial differences exist at parcel,transect,city,and national levels.Proximate causes,such as excessive land division,irregularly shaped land parcels,decreases in resident population,deindustrialization,land speculation,insufficient investment,and environmental concerns,can all result in UVL.Currently,UVL has become a gray area of social,economic,and ecological space.However,it can also be considered a potential resource for enhancing urban sustainability.Policy implications to promote urban sustainability using monitoring,control,and differential revitalization of UVL are presented.     

我心中的玛瑙湖

很早就有进入玛瑙湖的打算. 一直想找机会,看一看长河落日圆,大漠孤烟直的塞外风光,或者闲暇时接一接地气,捡一捡石头,朝拜心中祈盼已久的玛瑙湖,这一切对我来说真的是一种莫大的消遣和受用. 然而,每当听说我要进湖时,几位石商朋友总是笑着摇头对我说,“还是别去了,现在什么也没有了,石头都被人捡完了.不去后悔一阵子,去了后悔一辈子……”然而,无论朋友怎样劝,我还是坚持一定要去,因为我和他们的追求不一样,心境也不大一样.     

典型硬质岩区泥石流的发育研究

泥石流一般发育在岩性强度低、岩性较为破碎的地区,由于岩性差,岩体较为破碎,它易形成泥石流的物源,配合一定的地形条件和气象条件,造成泥石流发生.硬质岩区由于其强度高,不容易发生崩塌、滑坡等,形成泥石流物源.本文通过一个硬质岩区发生的泥石流调查表明:在硬质岩区,由于不合理的人类活动,造成降雨水时,水从高处经过硬质岩崩塌坡积物向下流动时,由于在高比降情况下,水的侵蚀能力强,坡形陡,硬质岩崩塌坡积物容易垮塌为其提供了物源.它的发生频率高,对下游危害大,因此,在这种地区进行工程活动时,必须对这种现象引起高度的重视.     

老子出生地之谜可能还要谜下去

司马迁《史记》没记清民间传说说不清鹿邑县志写不清老子,姓李,名耳,字伯阳,春秋末期人,出生于鹿邑县,在洛阳担任周朝守藏史。他是世界公认的大哲学家,是百姓津津乐道的智慧老人。2500年前,他在函谷关留下《老子》(后称《道德经》)五千言,骑青牛悠悠西去,从此了无踪迹,不知所终……从此,洛阳城中少了一个旷世高人,文化宝库多了一道千     

风景小城 四面环水有5个湖泊环绕 风景小岛 家家临水有15条河流流淌 风景小桥 户户通舟有49座桥相连接 江苏省吴江市同里镇以悠久历史典型水乡风格“东方小威尼斯”的美誉推靓了其地名俏姿

同里隶属江苏省吴江市,位于太湖之滨,京杭大运河畔,紧依上海、苏州、杭州中国南方三大著名城市,距苏州市18公里,距上海80公里,面积33公顷,被五个湖泊环抱。同里风景优美,镇外四面环水,镇内由15条河流纵横分割为7个小岛,全镇由49座     

听得白狼山的心跳

来到辽西的人,谁能不为白狼山所心动?山的前面还是山。古老的燕山山脉提起精神,从河北平原北侧的潮白河谷启程,越过努鲁儿虎山,向着蔚蓝的渤海湾,一口气跋涉了600余公里,历苍茫而雄浑,聚烟霞而秀气,在辽西建昌县城东5公里处,惊讶于原野的广袤,仰天一声长叹,白狼山拔地而     

以剡溪水而得名 以“海上蓬莱”而闻名 以自然风光而著名 千年古镇溪口镇是游人如织的好地方

溪口镇,位于浙江省奉化市西北,距宁波市区22公里。溪口以剡溪之水而得名。剡溪源头,主流出于剡界岭,由新昌入奉化境,称“剡源”。沿溪风光优美,剡源九曲为古代旅游胜地。九曲公棠以下称“剡溪”,由西向东流过全镇,至东端,有武岭头与溪南山阻隔成口,“溪口”之名由此而来。又以武岭横亘镇东,以山名命地,故也称“武岭”。溪口风景名胜区位于浙江省宁波市西南20公里,为首批国家4A级旅游区,依山傍水,风光旖旎。     

北倚长城 境内绵延80余公里古长城有万里长城最窄处和千年长城交汇点 头枕燕山 境内有我国现存规模最宏大体系最完整的帝王陵建筑群 身偎滦水 鹫峰山禅林寺有国内现存规模最大的千年银杏园 “畿东第一城”遵化古韵古迹名胜佳境如画风景极大地拨动着游人们的心弦

遵化,头枕燕山,身偎滦水,北倚长城,西眺北京,南临津唐,东通辽沈,素有"畿东第一城"之称。遵化,自古便以"风水宝地"而被世人所称道。"万里河山有燕塞,千年风气自荆轲",充分展示了这里诱人的风貌。     

明代以来大陆泽与宁晋泊的演变过程

采用历史文献及地名学的研究方法,对明代以后海河南系平原地区的湖沼演变过程进行分析。结果表明,明代至16世纪后期,该区主要有南起任县、北至宁晋的广阔湖泊——大陆泽。17世纪初,大陆泽分解成南泊大陆泽与北泊宁晋泊。分解时,大陆泽比宁晋泊更为深广。此后大陆泽不断缩小,宁晋泊却持续扩大。至19世纪初,宁晋泊已3倍于大陆泽。19世纪二三十年代之后,两湖泊同时发生显著萎缩。19世纪末,大陆泽就已走向消涸,宁晋泊此时也已"不显泊形",并在20世纪初同样走向终结。     

基于多源空间数据的塔里木河下游湖泊变化研究

利用历史图件、地形图及遥感数据监测塔里木河下游诸多湖泊水域面积并分析近一百多年的变化情况。根据湖泊水域及其变化,该区湖泊在100多年内变化过程可以分为3个时间段：① 20世纪60年代以前,该区水文条件较好,19世纪末20世纪初湖泊总面积超过2000 km²;20世纪60-70年代至20世纪末,随着水利设施的陆续兴建,湖泊水域缩小,甚至某些湖泊彻底干涸;21世纪随着塔里木河流域综合治理与下游生态输水工程的实施,该区水文条件有所好转,干涸多年的一些湖泊重新形成水域,2013年湖泊水域总面积达760 km²。② 根据湖盆成因及水域变化把该区湖泊分为：河道西侧的风成湖,河道网之间及东侧的河成湖及河道末端的构造湖等三类。③ 初步总结风成湖演变过程,发现该区风成湖与河成湖在形状、深度、水质、形成时间等方面有较大差异。④ 近代人为因素对湖泊水域变化的影响高于自然因素。     

近百年湖北省湖泊演变特征研究

利用20世纪初以来的地图、历史文献资料和1986～2005年期间7年不同时相的TM影像数据,采用遥感和地理信息系统技术和方法,分析近百年湖北省湖泊的时空演变特征。研究结果表明:①近100多年来,湖北省湖泊演化可以分为4个阶段,并且具有明显的地域差异性。②20世纪初期,湖北省湖泊面积约为26000km2,到2005年为3025.6km2,仅为百年前的11.64%;近百年来绝大部分湖泊面积都在缩小,部分湖泊因围垦或其他原因已完全消失或变为它用,部分湖泊形态发生了较大变化;人类活动是湖北省湖泊百年变迁的主导因素。③20世纪下半叶湖北省湖泊变化迅速,湖北省湖泊面积由50年代的约8503.7km2波动减小至80年代的约2977.3km2,发生在60～80年代的围垦是造成湖泊萎缩的主要原因;从90年代开始,因重视湖泊保护和退田还湖,使湖泊萎缩的态势得到遏制,局部湖泊面积有所恢复。     

江苏省近两千年气候变化研究

建立一个温度指数序列和苏南、苏北两个旱涝等级序列,序列长度在６００￣１８００ａ间。分历史气候时期（近２０００ａ）和实测资料时期（近百年）对冷暖（温度）和旱涝（降水）变化规律作研究,提出宏观趋势。     

Recent lake level variations in Lake Haubi, central Tanzania, interpreted from pollen and sediment studies

Variations in pollen assemblages and in physical and chemical composition of a dated sediment record from the small Lake Haubi in north central Tanzania, reveal lake level fluctuations since the late 19th century. Lake Haubi changed from a seasonally inundated swamp to a lake in the beginning of the 20th century. With the exception of 1942-44, when it dried out completely, it remained water filled until 1994 when it again turned into a swamp. The lake level fluctuations in Lake Haubi are largely in phase with fluctuations of the larger East African lakes levels during the 20th century, and are therefore interpreted as being mainly controlled by regional climatic fluctuations. However, the initial formation of Lake Haubi at the turn of the century was likely due to local catchment specific causes, e.g. changes in land use, as the rapid increase in the water level at this time does not correspond to other lake level records from the region.     

基于雷达遥感的内蒙古额济纳旗东北部中晚早更新世古水系演化

Radar remote sensing can acquire information of sub-surface covered by sand in arid area,detect surface roughness and vegetation coronet′s layer and linear feature such as linear structure and channel sensitively. With sediment facies analysis, this paper studies the features of environmental evolution in mid-late Epipleistocene (60 ka BP-20 ka BP) in northeastern Ejin Banner. The conclusions are listed as follows: (1) The evolution of the three lakes, i.e. Gaxunnur, Sugunur and Tian′e lakes, are dominated by faults and regional climate. (2) By analyzing sedimentary section of old Juyanze Lake,the three lakes used to be a large outflow lake before 50 ka BP in northeastern Ejin Banner, and at 50ka BP, temperature declined rapidly in northwestern China. The event caused the lake′s shrinkage. (3)By fault activity uplift in the northern part of old Juyan Lake and depression in the southern part, the lake′s water followed from north to south at around 35 ka BP, old Juyanze fluvial fan was formed. At the same time, Juyan Lake separated from Sugunur Lake and Wentugunr old channel was abandoned.(4) In recent 2000 years, Ruoshui River is a wandering river, sometimes it flows into Juyan Lake and sometimes Sugunur and Gaxunnur lakes. Due to human activities and over exploitation, the oasis ecosystem is rapidly degenerated in 15 years (1986-2000).     

Former glacial lakes of the Bunger Hills,Antarctica

The Bunger Hills in East Antarctica occupy a land area of approximately 400 km². They have been exposed by Holocene retreat of the Antarctic ice sheet and its outlet glaciers. The accompanying sea level rise flooded the marine inlets that now separate the northern islands and peninsulas from the major part of the hills. During deglaciation the continental ice sheet margin retreated south‐eastwards with several temporary halts, during which ice‐dammed lakes were formed in some valleys. These lakes were maintained long enough to permit formation of beaches of sand and gravel, and for the erosion of shore platforms and low cliffs in bedrock. Around the western end of Fish Tail Bay impressive shoreline features 20 m above sea level define a former ice‐dammed lake that was 5.5 km long. A similar 7 km long former ice‐dammed lake was formed at Lake Dolgoe. The more extensive and deeper glacial lake is revealed by well‐developed and preserved shoreline features cut at 29 m which is 16 m above present lake level. In addition, several small ice‐dammed lakes existed temporarily near Lake Shchel and in the valley to the west. Lake Fish Tail existed more than 6,900 ¹⁴C years ago and Lake Shchel probably more than 6,680 ¹⁴C years ago. It is inferred that the shore platforms and beaches were formed by lake ice and wave action over considerable periods when the lakes were impounded by steep cold ice margins. There appears to have been a balance between meltwater input and evaporative loss from the lakes in the cold dry continental climate. There is no evidence for rapid lake level fluctuations, and there was very little input of clastic sediment. This resulted in poor development of deltaic and rhythmically laminated lake floor deposits. It is suggested that such deposits are more characteristic of ice‐dammed lakes formed in association with wet‐based temperate ice than those associated with dry‐based polar ice.     

中国东西部平原区湖泊近期变化之比较

本文通过对中国部湖泊近期演化及其对环境影响的比较研究，认为导致东西部湖泊近期大面积退缩的主要原因都是人类活动。平原区湖泊的许多传统功能正逐渐被水利工程所取代，今后湖区资源的开发应充分注意这一趋势。     

Historical genetics on a sediment core from a Kenyan lake: intraspecific genotype turnover in a tropical rotifer is related to past environmental changes

Using molecular genetic methods and an ancient DNA approach, we studied population and species succession of rotifers of the genus Brachionus in the Kenyan alkaline-saline crater lake Sonachi since the beginning of the 19th century as well as distribution of Brachionus haplotypes in recent and historic sediments of other lakes of the East African Rift System. The sediment core record of Lake Sonachi displays haplotypes of a distinct evolutionary lineage in all increments. Populations were dominated by a single mitochondrial haplotype for a period of 150 years, and two putatively intraspecific turnovers in dominance occurred. Both changes are concordant with major environmental perturbations documented by a profound visible change in sediment composition of the core. The first change was very abrupt and occurred after the deposition of volcanic ash at the beginning of the 19th century. The second change coincides with a major lake level lowstand during the 1940s. It was preceded by a period of successively declining lake level, in which two other haplotypes appeared in the lake. One of these putatively belongs to another species documented in historical and recent Kenyan lake sediments. The analysis of plankton population dynamics through historical time can reveal patterns of population persistence and turnover in relation to environmental changes.     

我国亚热带划分中的一些问题

我国的亚热带幅员辽阔、物产丰富、人口密集、地形复杂、气候多样,气候带如何划分是一个重要问题。在区划的原则、等级、指标和界线等问题上,都有不同的看法。作者就这些问题发表了意见,并提出了划分亚热带的具体方案。