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1.
The variability and dynamic mechanism of the East Asian monsoon climate is a major scientific puzzle in the exploration of global change. As early as in the late 1990s, a research team led by Prof. AN Zhisheng from the CAS Institute of Earth Environment started their work in this topic, with an objective of improving the hypothesis of monsoon-controlled East Asian environment and advancing the basic studies of past global changes in eastern Asia.  相似文献   

2.
In Xishuangbanna, one of China＇s most biodiverse regions, landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations. In steep areas, terraces are often constructed before planting rubber trees, which causes two important changes in the soil： the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion. Few studies have documented the nature and intensity of erosion on bench terraces.  相似文献   

3.
正Rubber trees(Hevea brasiliensis)were first introduced to tropical Asia at the end of the 19~(th)century,and Xishuangbanna is a top rubberproducing region in China.Previous studies on rubber plantations have focused on the impacts of land-use conversion upon tropical biodiversity,soil and water  相似文献   

4.
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence  相似文献   

5.
The Tibetan Plateau (Qinghai-Xizang Plateau)is a unique geological-geographical unit on Earth, an ideal region for studies into the formation and evolution of the lithosphere and the dynamic mechanism of the earth crust. The uplifting of the Plateau exerts profound influence upon the evolution and differentiation of the natural environment of the plateau itself, its adjacent regions and the Northern Hemisphere. As a unique natural geographical unit, the Plateau holds a special status in the whole globe due to its special natural environment and ecosystems, which is also in close relation to global environmental change.The significance of the Plateau research should be recognized not only in the fundamental research fields of geo-sciences and biology, but also in its application to resource exploitation, environmental protection and sustainable development of the Plateau region.  相似文献   

6.
CAS formally became a member of the Association of Academies of Sciences in Asia (AASA) at the fourth general assembly of AASA from Sept. 23 to 25 in Tehran, Iran. A CAS delegation headed by Vice-President Yang Bailing attended the conference.AASA is a non-profit international organization of the Asian and Australasian regions, comprising 20 academies with science and technology interests. Its main objectives are  相似文献   

7.
<正>The subtropical evergreen broadleaved forests(EBLFs),ranging in occurrence from c.23°N to 39°N and 97°E to 141°E,are amongst the most characteristic biomes in East Asia and are common in South China.They contribute fundamentally to both the biodiversity function and ecosystem services of the East Asiatic floristic kingdom.The East Asian subtropical EBLFs are considered as unique zonal vegetation that might have developed in concert with the Asian monsoons,particularly the  相似文献   

8.
<正>Rapid major shits in vegetation types are most oten atributed to abrupt climate changes.However,recent studies have revealed non-linear vegetation responses to current global warming on the Tibetan Plateau[1].his also seems to be the case for the Holocene vegetation on the Tibetan Plateau.his high-elevation region is under the control of the Asian monsoon,causing relatively moist summers and dry winters.Monsoon inluence rapidly decreases from the southeastern to the northwestern parts of the  相似文献   

9.
正Over the past half century,a warming trend,the fastest seen so far,emerged in the arid and semi-arid regions in mid-latitudes of the Northern Hemisphere featuring fragile ecological systems.As predicted by scientists,the arid area will continue to expand,due to dual influence from both climate change and human activities;and about three-quarters of the drought expansion will happen in developing countries.  相似文献   

10.
PIWI-interacting RNAs(piRNAs) are a complex class of small non-coding RNAs that are mostly 24–32nucleotides in length and composed of at least hundreds of thousands of species that speciically interact with the PIWI protein subfamily of the ARGONAUTE family. Recent studies revealed that PIWI proteins interact with a number of proteins, especially the TUDOR-domain-containing proteins, to regulate piRNA biogenesis and regulatory function. Current research also provides evidence that PIWI proteins and pi RNAs are not only crucial for transposon silencing in the germline, but also mediate novel mechanisms of epigenetic programming, DNA rearrangements, m RNA turnover, and translational control both in the germline and in the soma. hese new discoveries begin to reveal an exciting new dimension of gene regulation in the cell.  相似文献   

11.
I. Research Highlights(1) A relatively clear picture has been formedregarding the environment evolution process inwestern China during different periods, giving ananswer to the question: What on earth did it look like?The issue is examined at three different timedimensions, i.e., during the geological period, 2,000 and50 years ago. According to the studies, the spatial pat-tern of arid areas in Northwest China took shape roughlyone million years ago. Although there was a relativehumid and w…  相似文献   

12.
正The Qinghai-Tibet Plateau(Tibetan Plateau)serves as an important shelter to safeguard China's environment and ecological system.Its vast area and lofty altitude have a strong bearing on the atmospheric circulation and climate pattern over the plateau and its surrounding regions.With numerous glaciers,large area of permafrost,a variety of lakes and a dozen of large rivers,it plays an important role in water source supply and  相似文献   

13.
The kick-off meeting for CEOPAEGIS, an international cooperation project between Europe and Asia to improve knowledge on hydrology and meteorology of the QinghaiTibet Plateau and its role in climate, monsoon and extreme meteorological events, was held from 26 April to 3 May at the CAS Institute of Tibetan Plateau Research （ITP） in Beijing.  相似文献   

14.
<正>Bulbophyllum Thouars is among the largest genera in the orchid family,consisting of 1,868species and widely distributed in tropical Africa,Asia and South America.There are approximately 32species in section Lemniscata,mainly growing in South to South-East Asia.During a botanical survey between  相似文献   

15.
The nations of tropical Asia should expand the number and size of protected areas within their borders, especially for forest types and ecoregions that are poorly protected in existing reserves,and for the increasingly rare areas that still retain their highly vulnerable megafauna, urges a declaration of more than 300 biologists from about 40 countries and regions.  相似文献   

16.
<正>Severe drought events are serious issues in north China,particularly since the end of the 1970s when the East Asian monsoon became weakened and the monsoon rainfall decreased dramatically in the area.In the summer of 2014,North China suffered from a major drought,which turned out to be the worst for some provinces in the past 60 years.  相似文献   

17.
The ecological water diversion project in the Heihe River Basin is the irst successful case in China in which the ecological systems in a river basin have been rescued. his project serves as a valuable example for the management of ecosystems in other inland river basins. his paper reviews the integrated studies of the water–ecosystem–economy relationship in the Heihe River Basin and concludes that sustainable development in inland river basins requires the basin to be considered as a whole, with the relationships between the upstream, midstream and downstream areas of the basin coordinated appropriately. Successful development in these basins will be relected in an improved output per cubic meter of water and the implementation of integrated river basin management practices.  相似文献   

18.
基于主题分布的我国情报学文献计量分析   总被引：6，自引：0，他引：6  
With a statistical analysis of the research papers on information studies published from 1991 to 2000 in China, this article makes a bibliometric analysis of the subject distribution of these papers so as to reflect the present situation and development trend of researches on information studies in China.  相似文献   

19.
<正>Rubber(Hevea brasiliensis)is one of the most rapidly expanding cash crops in tropical Asia especially Xishuangbanna.Conserving tropical forest largely depends on the effective management of human-modified landscapes.It is crucial to identify measures to improve biodiversity outcomes in rubberforest mosaics for tropical fauna.  相似文献   

20.
1.  The distribution of Salix species among the continents.  There are about 526 species of Salix in the world, most of which are distributed in the Northern Hemisphere with only a few species in the Southern Hemisphere.  In Asia, there are about 375 species, mak- ing up 71.29 percent of the total in the world, including 328 endemics; in Europe, about 114 species, 21.67 percent with 73 endemics; in North America, about 91 species, 17.3 percent with 71 endemics; in Africa, about 8 species, 1.5 percent, with 6 endemics.  Only one species occurs in South America.  Asia, Europe and North America have 8 species in common (excluding 4 cultivated species).  There are 34 common species between Asia and Europe, 14 both between Europe and North America and between Asia and North America, 2 between Asia and Africa. Acording to the Continental Drift Theory, the natural circumstances which promoted speciation and protected newly originated and old species were created by the orogenic movement of the Himalayas in the middle and late Tertiary.  Besides, the air temperature was a little higher in Asia than in Europe and North America (except its west part) and the dominant glaciers were mountainous in Asia during the glacial epoch in the Quaternary Period.  Then willows of Eu- rope moved southwards to Asia.  During the interglacial period they moved in opposite direc- tion.  Such a to-and-fro willow migration between Asia and Europe and between and North America occurred so often that it resulted in the diversity of willow species in Asia.  Those species of willows common among the continents belong to the Arctic flora.      2.  The multistaminal willows are of the primitive group in Salix.  Asia has 28 species of multistaminal willows, but Europe has only one which is also found in Asia.  These 28 species are divided into two groups, “northern type” and “southern type”, according to morphology of the ovary.  The boundary between the two forms in distribution is at 40°N.  The multistami- nal willows from south Asia, Africa and South America are very similar to each other and may have mutually communicated between these continents in the Middle or Late Cretaceous Period.  The southern type willows in south Asia are similar to the North American multista- minal willows but a few species.  The Asian southern type willows spreaded all over the conti- nents of Europe, Asia and North America through the communication between them before the Quaternany Period.   Nevertheless, it is possible that the willows growing in North America immigranted through the middle America from South America.  The Asian northern type mul- tistaminal willows may have originated during the ice period.      The multistaminal willows are more closed to populars in features of sexual organs.  They are more primitive than the willows with 1-3 stamens and the most primitive ones in the ge- nus.      3.  The center of origin and development of willows Based on the above discussion it is re- asonable to say that the region between 20°-40°N in East Asia is the center of the origin and differentiation of multistaminal willows.  It covers Southern and Southwestern China and nor- thern Indo-China Pennisula.  相似文献   

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