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921.
Six new species of the Drosophila robusta species group are described from Southeast Asian Islands. Kalimantan and Sunda Islands lie east of Bali, from which Drosophila barobusta sp.nov and D. uncinata sp.nov belong to the lacertosa subgroup, and D. sungaicola sp.nov, D. baliensis sp.nov, D. hitam sp.nov and D. subaquatica sp.nov to the okadai subgroup. The robusta group from Southeast Asian tropics exclusively inhabits streamsides in mountainous highlands with an elevation of more than 600 m from the sea level. 相似文献
922.
根据从印度库茂恩(Kumaun)喜马拉雅纳尼塔尔(Naini Tal)温带地区获得的85cm钻井的孢粉资料,恢复了1720+/-130年以来晚全新世古植被演变史,并推测了当地的古气候,当前孢粉资料说明了该地区当时发育有栎树混交林和波动的温暖润气候,孢粉组合序列的初始阶段,森林距沉积盆地较远,但是,由于气候变得更加温暖潮湿,森林也很快茂密起来,约1200年前,因气候恶化,森林变得稀疏,而在约124年前,气候再次转好,麦类及其他作物花粉资料证明农耕活动大约开始于1460年前左右。 相似文献
923.
This research deals with the History of the human peopling of Far East Asia during the Late Upper Pleistocene. It brings some new answers to the question of modern human migrations in the Far East. This study is based on morphometric analysis of 45 fossil crania. The results of the multivariate analyses, combined with the recognition of geographic patterns of variation, separate the fossils into three morphological classes. These three clusters enable us to propose a likely scenario for the human peopling of the Far East from about 67 000 years ago. To cite this article: F. Demeter et al., C. R. Palevol 2 (2003). 相似文献
924.
The Dry Holocene Megathermal in Inner Mongolia 总被引:5,自引:0,他引:5
Chen-Tung A Chen Hsin-Chi LanJiann-Yuh Lou Yan-Cheng Chen 《Palaeogeography, Palaeoclimatology, Palaeoecology》2003,193(2):181-200
The paleoclimate since 14 kyr BP (14C age) was reconstructed based on a 16.22-m-long sediment core collected from Lake Yanhaizi, a saline lake located near the northern limit of the East Asian summer monsoon in Inner Mongolia. Coarse sediments were deposited there during a shrinkage phase of the lake when sand dunes reactivated. These sediments have low organic carbon contents but high maturity indices, indicating that they were deposited in an arid environment. By contrast, based on high organic contents and low maturity indices, fine sediments were deposited during periods of high lake stand in a humid environment. It was in general dry between 8.0 and 4.3 kyr BP. The above dry and wet phases are consistent with those recovered from the arid-semiarid transition zone elsewhere, but are unlike the widely perceived humid Holocene Megathermal reported in east China and the newly reconstructed record in the alpine Retreat Lake in Taiwan. The discrepancy may be due to a relative insensitivity to humidity changes in these two areas since they have both been under the total influence of the summer monsoon. On the other hand, much enhanced evaporation over higher monsoon precipitation at Lake Yanhaizi reduces the effective humidity in the warm climate near the northern boundary of the summer monsoon. This also accounts for the fact the high-temperature Holocene Megathermal, as revealed in the Okinawa Trough and the northern South China Sea, is correlated to the dry phases at Lake Yanhaizi. Conversely, the 4-2-kyr BP coldest period in the Holocene corresponds to a wet phase at Lake Yanhaizi. 相似文献
925.
Larissa Vasilyeva 《Mycoscience》2001,42(4):399-401
Rossmania ukurunduensis gen. and sp. nov. collected in the reverve Bolshekhekhtsirsky (Khabarovsk Territory, Russian Far East) is described and illustrated.Rossmania aculeata comb. Nov. is indicated as the second species of the genus. 相似文献
926.
D. Rivera C. Inocencio C. Obón E. Carreño A. Reales F. Alcaraz 《Vegetation History and Archaeobotany》2002,11(4):295-314
The origins of capers, their use and cultivation are discussed. Capers seeds and charcoal are often recovered from archaeological
sites of the Mediterranean and West Asia. These are referred to as C. Spinosa L. This is mostly a group of cultivars restricted to localities surrounding the Western Mediterranean and some places in
the Eastern Mediterranean. Identification of the findings is discussed in terms of seed morphology, present distribution and
ancient uses of C. aegyptia Lam., C. sicula Veill., C. cartilaginea Decne, C. orientalis Veill., C. decidua (Forssk.) Edgew. and other species. Citations of Capparis in early Rabbinic, Mesopotamian and Greco-Roman texts are presented.
Received June 3, 2002 / Accepted October 8, 2002
Correspondence to: D. Rivera 相似文献
927.
Hamish G. Robertson 《Biodiversity and Conservation》2002,11(9):1637-1652
Ants were extracted in Winkler bags from sifted leaf litter sampled in arange of forest and woodland types in and around Mkomazi Game Reserve innorth-eastern Tanzania, including the Eastern Arc Mountains of South Pare andWest Usambara. A total of 87 ant species were recorded, of which 32.2% were onlyrecorded from montane forests (1400–1850 m altitude), 6.9%only from lowland forest (540–810 m), 19.5% only fromwoodland (300–1080 m), and 16.1% in all three forest types.Of the 28 species recorded only from montane forests, 12 species were only foundin the Mkomazi forests, four only in the Pares and seven species only in theUsambaras. Sites of similar altitude grouped together in a cluster analysis, andspecies richness decreased with an increase in altitude. The lowland forest andclosed woodland sites did not form distinct communities. To ensure preservationof ant species, forests from a full range of altitudes need to be conserved.This study confirms the status of the West Usambara forests as having a highlyendemic biota, and the critical need to adequately conserve the remainingvestiges of montane forest within Mkomazi Game Reserve. 相似文献
928.
Large-scale phytogeographical patterns in East Asia in relation to latitudinal and climatic gradients 总被引:8,自引:0,他引:8
Hong Qian Jong-Suk Song Pavel Krestov Qinfeng Guo Zemin Wu Xiansheng Shen Xiaosi Guo 《Journal of Biogeography》2003,30(1):129-141
Aim This paper aims at determining how different floristic elements (e.g. cosmopolitan, tropical, and temperate) change with latitude and major climate factors, and how latitude affects the floristic relationships between East Asia and the other parts of the world. Location East Asia from the Arctic to tropical regions, an area crossing over 50° of latitudes and covering the eastern part of China, Korea, Japan and the eastern part of Russia. Methods East Asia is divided into forty‐five geographical regions. Based on the similarity of their world‐wide distributional patterns, a total of 2808 indigenous genera of seed plants found in East Asia were grouped into fourteen geographical elements, belonging to three major categories (cosmopolitan, tropical and temperate). The 50°‐long latitudinal gradient of East Asia was divided into five latitudinal zones, each of c. 10°. Phytogeographical relationships of East Asia to latitude and climatic variables were examined based on the forty‐five regional floras. Results Among all geographical and climatic variables considered, latitude showed the strongest relationship to phytogeographical composition. Tropical genera (with pantropical, amphi‐Pacific tropical, palaeotropical, tropical Asia–tropical Australia, tropical Asia–tropical Africa and tropical Asia geographical elements combined) accounted for c. 80% of the total genera at latitude 20°N and for c. 0% at latitude 55–60°N. In contrast, temperate genera (including holarctic, eastern Asia–North America, temperate Eurasia, temperate Asia, Mediterranean, western Asia to central Asia, central Asia and eastern Asia geographical elements) accounted for 15.5% in the southernmost latitude and for 80% at 55–60°N, from where northward the percentage tended to level off. The proportion of cosmopolitan genera increased gradually with latitude from 5% at the southernmost latitude to 21% at 55–60°N, where it levelled off northward. In general, the genera present in a more northerly flora are a subset of the genera present in a more southerly flora. Main conclusions The large‐scale patterns of phytogeography in East Asia are strongly related to latitude, which covaries with several climatic variables such as temperature. Evolutionary processes such as the adaptation of plants to cold climates and current and past land connections are likely responsible for the observed latitudinal patterns. 相似文献
929.
930.