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1.
生态水文学学科体系及学科发展战略   总被引:1,自引:1,他引:0  
生态水文学是一门新兴学科,构建完善的学科体系、制定未来发展战略,对推动生态水文学学科发展具有重要意义。通过查阅文献资料,系统梳理和阐述了生态水文学学科的发展历程,共划分为5个阶段,即生态水文学萌芽期(1970年左右至1986年)、术语提出与初步探索期(1987—1991年)、学科建立与初步发展期(1992—1995年)、学科快速发展期(1996—2007年)和学科完善期(2008年至今);基于对该学科发展历程的分析,提出了以"理论—方法—实践—分支学科"为框架的生态水文学学科体系;最后,从学科研究计划、重点研究项目、国家重大需求、学科建设和国际合作5个方面对生态水文学学科未来发展战略进行了展望,为促进和建立完善的生态水文学学科体系提供支撑。  相似文献   

2.
南印度克拉通(Godvari-Narmada裂系的南部和西南部)是由年龄为3400Ma~600Ma的岩石组成。这些岩石构成(1)太古代Karnataka和Jeypore-Bestar陆核(2600Ma);(2)早元古活动带(2300~2000Ma);(3)中元古活动带(2000~1500Ma);(4)元古代沉积盆地(1700~700Ma);和(5)Kerala和邻近地区的晚元古高级麻粒岩地体。两个陆核的太古代岩石,特别是Karnataka陆核,发育了1000Ma时期的岩石,并显示了较大的成分差异。这些陆核是由多期片岩带的片麻岩和花岗岩组成。现在发现几个  相似文献   

3.
冯景蘭 《地质论评》1946,11(Z3):400-401
根据时间和空间之两概念以研究矿产,名造成矿床之地质时代,为造卵时期;矿产所分布之地区,为矿产区域。(甲)云南之造矿时期为:(一)太古代(含金石英脉);(二)震旦纪(东川式铜矿及易门式铁矿);(三)寒武纪(昆阳式磷矿);(四)石  相似文献   

4.
卢良兆教授1930年生于浙江省黄岩县,1950~1952年就读于南京地质探矿专科学校,毕业后一直在长春地质学院(合校后为吉林大学地球科学学院)任教,1985年晋升为教授,1990年评聘为岩石学博士生导师.  相似文献   

5.
卢良兆教授1930年生于浙江省黄岩县,1950~1952年就读于南京地质探矿专科学校,毕业后一直在长春地质学院(合校后为吉林大学地球科学学院)任教,1985年晋升为教授,1990年评聘为岩石学博士生导师.  相似文献   

6.
水文科学的基本问题及当代前沿   总被引:1,自引:4,他引:1       下载免费PDF全文
刘国纬 《水科学进展》1990,31(5):685-689
回顾了新中国70年来水文科学的发展历程。阐述了水文科学的基本问题及其当代前沿:水圈及其与地球其他圈层的界面过程;水文循环及人类活动对水文循环的扰动;水文学研究的特点及其方法论;水文知识的应用等。提出了划分水文科学分支学科的科学基础,建议将水文科学划分为普通水文学、水文气象学、陆地水文学、生态水文学和应用水文学5个分支学科。  相似文献   

7.
刘国纬 《水科学进展》2020,31(5):685-689
回顾了新中国70年来水文科学的发展历程。阐述了水文科学的基本问题及其当代前沿:水圈及其与地球其他圈层的界面过程;水文循环及人类活动对水文循环的扰动;水文学研究的特点及其方法论;水文知识的应用等。提出了划分水文科学分支学科的科学基础,建议将水文科学划分为普通水文学、水文气象学、陆地水文学、生态水文学和应用水文学5个分支学科。  相似文献   

8.
国际水资源协会名誉主席、美国伊利诺斯大学教授周文德于1980年6月18日至7月11日来我国讲学,其中随机水文学是周教授在京期间的主要讲学内容。这次讲的随机水文学共有五个方面:(一) 随机水文学基础;(二) 水文时间序列;(三) 拟随机流域系统;(四) 随机流域系统;(五) 长记忆随机水文模型。现由地理所同志整理成本文,以供我国水文工作者学习参考。  相似文献   

9.
程懋堃简介程懋堃,1930年生于南京,1950年毕业于上海交通大学土木工程系。现任北京市建筑设计研究院顾问总工程师。1951年~1952年上海基泰建筑结构工程设计事务所工程师,1952年~1954年北京兴业公司建筑工程设计部工程师,1954年~1986年北京市建筑设计研究院结构组长、设计室主任工程师,1986年~1998年北京市建筑设计研究院院总工程师,1999年~至今,北京市建筑设计研究院聘为院顾问总工程师。Maokun Cheng,born in1930in Nanjing,graduated from civil engineering of Shanghai Jiaotong University in1950.Now he is consultingchief e…  相似文献   

10.
消息报道     
《水文》1986,(2)
《环境水文学》讲座在南京举办受水电部水文局的委托,南京水文水资源研究所于1986年3月11日至22日在南京举办了《环境水文学》讲座。来自全国6个流域的水资源保护局(办)和23个省(自治区、直辖市)以及有关院校、设计、科研单位的水质科技人员共56人参加了这次讲座。环境水文学是运用水文学、水化学和生态学的理论和方法,研究水文状况变化对生态环境影响的一  相似文献   

11.
The spatial changes in forest cover of Similipal biosphere reserve, Odisha, India over eight decades (1930–2012) has been quantified by using multi-temporal data from different sources. Over the period, the forest cover reduced by 970.8 km2 (23.6% of the total forest), and most significantly during the period, 1930–1975. Human-induced activities like conversion of forest land for agriculture, construction of dams and mining activities have been identified as major drivers of deforestation. Spatial analysis indicates that 399 grids (1 grid = 1 × 1 km) have undergone large-scale changes in forest cover (>75 ha) during 1930–1975, while only 3 grids have shown >75 ha loss during 1975–1990. Annual net rate of deforestation was 0.58 during 1930–1975, which has been reduced substantially during 1975–1990 (0.04). Annual gross rate of deforestation in 2006–2012 is indeed low (0.01) as compared to the national and global average. This study highlights the impact and effectiveness of conservation practices in minimizing the rate of deforestation and protecting the Similipal Biosphere Reserve.  相似文献   

12.
An historical summary of the distribution and abundance of submerged aquatic vegetation (SAV) in the Chesapeake Bay is presented. Evidence suggests that SAV has generally been common throughout the bay over the last several hundred years with several fluctuations in abundance. The decline ofZostera marina (eelgrass) in the 1930’s and the rapid expansion ofMyriophyllum spicatum (watermilfoil) in the late 1950’s and early 1960’s were two significant events involving a single species. Since 1965, however, there has been a significant reduction of all species in most sections of the bay. Declines were first observed in the Patuxent, Potomac and sections of other rivers in the Maryland portion of the Bay between 1965 and 1970. Dramatic reductions were observed over the entire length of the bay from 1970 to 1975. Particularly severe losses were observed at the head of the bay around Susquehanna Flats as well as in numerous rivers along Maryland’s eastern and western shores. Changes in the lower, Virginia portion of the bay occurred primarily in the western tributaries. Greatest losses of vegetation occurred in the years following Tropical Storm Agnes in 1972. Since 1975 little regrowth has been observed in the Chesapeake Bay. Other areas along the Atlantic Coast of the U.S. during the same period have experienced no similar widespread decline. It thus appears that the factors affecting the recent changes in distribution and abundance of submerged vegetation in the bay are regional in nature. Causes for this decline may be related to changes in water quality, primarily increased eutrophication and turbidity.  相似文献   

13.
Eighty-two-year rainfall time series have been studied together with climatic patterns of NAO using classical statistical methods. Then, the wavelet approach has been applied to show annual (1 year (1y)) and inter-annual (2–4 years (2-4y), 5–8 years (5-8y), and 8–16 years (8-16y)) modes distributed following four major discontinuities: 1945, 1960, 1975, and 1995. The 1y, 2-4y, and 5-8y powers show high energy during the wet period 1922–1930 and a low one in 1928–1938. After 1945, the annual mode highlights a high energy while the inter-annual modes present low energy. Between 1975 and 1995, powerful modes of 1 and 2–4 years are identified with low power of 5-8y and 8-16y modes. Since 1995, the low power of 5–8y decreases, while the 8-16y mode emphasizes a high variability. The coherence between NAO and Marrakech precipitation is strongly defined for low frequencies with a total contribution of 75 %. This coherence is in phase in the beginning and presents out phase signs since 1945. The change of phase can be associated to a decreasing of coherence especially around 1990. This finding is useful to understand the relationship between the hydrological variability and NAO climate patterns in the southern side of the Mediterranean Sea.  相似文献   

14.
美国地理学家联合会会刊》代表着美国地理学的最高水平,其载文及其变化从一个侧面反映出美国地理学的发展历程。通过对其学术论文进行统计分析,考察美国地理学的总体地位和不同领域相对地位的变化,梳理美国地理学百年发展脉络,得出以下结论:20世纪以来美国地理学经历了战前初步发展、战后快速发展和20世纪80年代以来的持续发展三大阶段,美国地理学的第二个春天正在到来;逐步形成了环境科学,研究方法、模式和地理信息科学,自然与社会,人口、地方、区域,综合地理五大领域框架;长期关注与人类发展密切相关的问题,人文地理学始终占据主导地位;非常注重实践,强调理论来源于实践、应用于实践;研究领域相对稳定,但不同方向的相对地位却此消彼长。依据载文数量的相对比例,可以概括出美国地理学发展脉络:自然(1911—1915)→经济(1916—1920)→自然(1921—1925)→地图学(1926—1930)→地方(1931—1935)→自然(1936—1940)→地理教育(1941—1945)→生态环境(1946—1950)→地方(1951—1955)→经济(1956—1975)→自然(1977—1990)→经济(1990—2005)。上述研究领域、方向及其变化,也基本上代表了世界地理学的整体发展规律。   相似文献   

15.
A unique historical data set describing the 142 storms each producing losses in excess of $100 million in the United States during the 1950–89 period were analyzed to describe their temporal characteristics. The storms caused $66.2 billion in losses (in 1991 values), 76% of the nation's insured storm losses in this period. These extreme storm catastrophes (SCs) were most prevalent in the south, southeast, northeast, and central U.S., with few in and west of the Rocky Mountains. Storm incidences were high in the 1950s, low in the 1960s-early 1970s, and increased in the 1980s. Losses due to SCs peaked in the 1950s, again in the late 1960s, with a lesser peak after 1985. The areal extent of storm losses peaked after 1975 and was least in the 1960s. The temporal variations of the three storm measures (incidence, losses, and extent) did not agree except when they all peaked in the 1950s. Regionally-derived time distributions of SCs showed a marked north-south differences in the United States with a U-shaped 40-year distribution in the northern half of the nation, and a relatively flat trend until a peak in the 1980s in the southern regions. The temporal distributions of hurricane-caused catastrophes differed regionally with occurrences in the prime areas, the southern, southeastern, and northeastern U.S., each quite different. Temporal distributions of thunderstorm and winter storm catastrophes were regionally more uniform.  相似文献   

16.
This study presents a chronology of historical and measured flood events in the Papaloapan River basin of Mexico during 450 years. Twenty-eight historical floods were recorded during the period 1550–1948 on this river and one flood event (1969) in the instrumental era (1949–2000), of which 14 were extraordinary floods and only 15 were catastrophic ones. There were several flood-rich decades during 1860–1870, 1880–1890, 1920–1930 and 1940–1950. Wavelet analysis found a significant flooding periodicity of 58 years. The wavelet coherence analysis found that flooding had an in-phase relationship with the Atlantic Multidecadal Oscillation and also with the Pacific Decadal Oscillation. Logistic regression corroborated that there exists a positive relationship between floods events and these two natural climatic oscillations. The logistic regression model predicted correctly 92% of flood events.  相似文献   

17.
利用大连市1914-2013年近100 a气温、降水资料, 应用一元线性回归、小波分析、气候趋势系数等方法, 对大连市气温、降水的季节-年际变化特征进行了研究, 结果表明: 近百年来, 大连市气温的变化趋势与全国增暖的总趋势基本一致, 年平均气温以0.12℃·(10a)-1的增温率在上升; 以20世纪50年代中期为界, 出现了两个冷暖交替期, 1930年和1982年为两个增暖突变点, 20世纪90年代之后为增暖趋势最显著期; 伴随百年明显的增温趋势, 大连市年降水量有相应微弱的减少趋势, 递减率为4.57 mm·(10a)-1; 降水量变化具有明显的周期性, 同时又具有多时间尺度特征; 大连市降水的季节变化明显, 降水异常的幅度在雨季最大, 尤其是7-8月, 异常幅度的峰值所在月份也有较明显的年际变化.  相似文献   

18.
On the basis of observation of thin sections and 137Cs data, laminations in sediment are interpreted to be varves in Bolterskardet Lake (78°06' N, 16°01' E), Svalbard, the Arctic. Varves appear under a petrologic microscope as couplets of dark-silt and light-clay layers. The mechanism of varve formation is surmized as follows: each silt layer is the production of sediment inflow interpreted as mainly derived from snowmelt during summer; each clay layer was deposited in a stillwater environment during an ice-cover period. A light -clay layer provides an important index bed to identify the annual interface. The high accumulation rates, long period of ice cover, and topographically closed basin are probably all critical factors in forming and preserving varves. Varve thickness is known to be controlled mainly by summer temperature. The variation of varve thickness in Lake Bolterskardet can then be used to reconstruct summer temperature. The varve series show that there has been distinct decade-scale variability of summer temperature over the past 150 years. Warm periods occurred in the 1860s, around 1900, the 1930s, 1950s, and 1970s, and in the last 20 years. The varved sediments of Lake Bolterskarde preserve an ideal record for high-resolution paleoclimatic and paleoenvironmental research in this data-sparse area.  相似文献   

19.
Volodin  E. M.  Gritsun  A. S. 《Doklady Earth Sciences》2018,482(1):1221-1224

Variations in the temperature of the Earth’s surface over the period 1850–2014 are reproduced and analyzed using seven historical calculations in the INM-CM5 climate model following the scenarios suggested for the CMIP6 project of comparison of climate models. In all calculations, the mean surface temperature increased by 0.8 K to the date of final calculation (2014), which is consistent with observations. The periods of accelerated warming (1920–1940 and 1980–2000) and its stabilization (1950–1975 and 2000–2014) are correctly reproduced by the model. The decrease in global warming of 2000–2014, which is hardly reproduced by the models in the CMIP5 experiment, is reproduced due to the more precise scenario of variation in the solar constant of CMIP6 protocols. The spatial structure of warming for last 30 years is also reproduced by the model.

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20.
刘强 《地质科学》2022,57(1):294-314
中央地质调查所作为中华民国时期成立最早、规模最大、最具国际声誉的国家级研究机构,在南京解放后它的演变过程目前尚缺少详实而准确的文献资料。本文基于历史档案,结合有关文献,较为详细地梳理了1949~1951年中央地质调查所先后被南京市军管会文化教育委员会(1949年5月~1950年6月)、华东军政委员会教育部(1950年7月~1950年12月)、中国地质工作计划指导委员会(1951年1月3日~1951年5月6日)接管的过程。本文还整理了1949年11月1日中国科学院正式成立后,中央地质调查所全所工作人员一致希望隶属中国科学院的经过,以及最终于1951年5月7日奉命改组为中国科学院地质研究所的过程。  相似文献   

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