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31.
简要介绍了澳大利亚被子植物区系的成分构成,主要代表科、属、及其种数;对其区系特征、特有类群、干旱适应及与其它地区植物区系成分的关系等问题进行了分析,并对其起源问题进行了初步探讨.  相似文献   
32.
澳大利亚墨累-达令流域管理的经验   总被引:5,自引:0,他引:5  
于秀波 《江西科学》2003,21(3):151-155
墨累-达令流域位于澳大利亚,在流域管理方面享有盛誉。本文简要介绍流域概况与所面临的威胁,介绍了流域管理机构,并分析了对该流域管理至关重要的《墨累-达令流域行动》、自然资源管理战略(后期改为流域综合管理战略)、以及土地关爱计划社区等,最后总结了该流域管理的经验以及我国流域管理的启示。  相似文献   
33.
以澳大利亚西北陆架勘探现状和油气田最新资料为基础,采用油气地质综合分析方法,探讨油气成藏主控因素与有利勘探方向。研究结果表明:成藏主控因素为"源盖控区,大型浪控海相三角洲控藏"。北卡那封(North Carnavon)盆地发育滦金(Rakin)台地与埃克斯茅斯(Exmauth)台地两大有利区和古新统海相浊积砂岩潜在油气富集体。波拿巴(Bonaparte)盆地已有巨型油气田中发现的萨胡尔(Sahul)台地、武尔坎(Vulean)次盆和玛丽塔(Malita)地堑等较成熟探区再有重大发现的潜力仍然巨大,上白垩统Puffin组水下扇和斜坡扇浊积砂岩与阿什莫尔(Ashmon)台地中新统生物礁是该盆地两大新领域。布劳斯(Browse)盆地存在围绕盆地富烃凹陷卡斯威尔(Caswell)次盆分布的4大油气富集有利构造带和Puffin组浊积砂岩潜在有利勘探目标层位。柔布克(Roebuck)盆地勘探程度极低,各成藏条件有待于厘定。  相似文献   
34.
The relationship between winter sea surface temperature (SST) east of Australia and summer precipitation in the Yangtze River valley and a possibly related physical mechanism were investigated using observation data. It is found that winter SST east of Australia is correlated positively to summer precipitation in the Yangtze River valley. When the SST east of Australia becomes warmer in winter, the western Pacific subtropical high and the East Asian westerly jet tend to shift southward the following summer, concurrent with low-level southwesterly anomalies over eastern China. These conditions favor precipitation increase in the Yangtze River valley, whereas the opposite conditions favor precipitation decrease. The influence of winter SST east of Australia on East Asian summer atmospheric circulations may occur in two ways. First, by an anomalous SST signal east of Australia in winter that persists through the following summer, thus affecting East Asian atmospheric circulations via the inter-hemispheric teleconnection. Second, when the SST east of Australia is warmer in winter, higher SST appears simultaneously in the southwest Indian Ocean and subsequently develops eastward by local air-sea interaction. As a result, the SST in the Maritime Continent increases in summer, which may lead to an anomalous change in East Asian summer atmospheric circulations through its impact on convection.  相似文献   
35.
We have investigated the ciliated protozoa living in the crater-lake of an extinct volcano in Australia. Our principal objective was to discover if such a habitat— geographically distant and isolated from Europe (the latter having provided most of the diversity on which ciliate taxonomy is based)— could yield species that were unusual, and perhaps new to science. Numerous samples were taken from the superficial layer of lake sediment, and examined fresh in the laboratory. Thereafter, the samples were manipulated to encourage growth of rare and cryptic ciliate species. Eighty-five species of ciliated protozoa were identified. None of these was new, all having been found previously in fresh-or brackish water, sea water, or soil. All, apart from one (Oxytricha salmastra), are already known from Europe. In order to test our ability to discover new ciliate species, we examined a variety of water samples from other lakes, including those known to harbour endemic algae. One new ciliate species (Lembadion curvatum) was discovered in a lake in Western Tasmania. We conclude that the ciliate fauna of Australia is remarkably similar to that in Europe and other parts of the world. This is supported by the example of those ‘endemic’ ciliate species described in the literature which have, in response to additional sampling, been found elsewhere in the world.  相似文献   
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《Journal of Natural History》2012,46(17-20):999-1023
Seven species of the marine enchytraeid genus Grania Southern, 1913 are described from sediments sampled during the 2003 International Workshop on the Marine Flora and Fauna of Esperance Bay and the Recherche Archipelago, on the southern coast of Western Australia. Two species are new to science, the euryhaline Tasmanian G. dolichura Rota and Erséus, 2000 Rota, E. and Erséus, C. 2000. Two new and peculiar species of Grania (Annelida: Clitellata: Enchytraeidae) inhabiting Tasmanian estuaries.. New Zealand Journal of Zoology, 27: 245254. [Taylor & Francis Online], [Web of Science ®] [Google Scholar] represents a new record for the state, and the remaining four species were known from other parts of Western Australia. Grania quaerens sp. n. is recognized by having a high chaetal index ( = short chaetal foot), small coelomocytes, penial apparati with long whip‐like terminal stylets, conspicuous spermathecae with ectally bulbous ducts, and ectally granulated ampullae housing sperm rings in their ental region. Grania sperantia sp. n. is readily distinguishable by the complete lack of lateral chaetae, a multiple‐banded pattern of the clitellum, extremely long sperm funnels, and the intrasegmental location of the spermathecal pores. The latter new species and four others in the collection (G. bykane Coates, 1990 Coates, K. A. 1990. “Marine Enchytraeidae (Oligochaeta, Annelida) of the Albany area, Western Australia.”. In The marine flora and fauna of Albany, Western Australia, 1, Edited by: Wells, F. E, Walker, D. I, Kirkman, H and Lethbridge, R. 1341. Perth: Western Australian Museum.  [Google Scholar], G. crassiducta Coates, 1990 Coates, K. A. 1990. “Marine Enchytraeidae (Oligochaeta, Annelida) of the Albany area, Western Australia.”. In The marine flora and fauna of Albany, Western Australia, 1, Edited by: Wells, F. E, Walker, D. I, Kirkman, H and Lethbridge, R. 1341. Perth: Western Australian Museum.  [Google Scholar], G. dolichura, and G. ersei Coates, 1990 Coates, K. A. 1990. “Marine Enchytraeidae (Oligochaeta, Annelida) of the Albany area, Western Australia.”. In The marine flora and fauna of Albany, Western Australia, 1, Edited by: Wells, F. E, Walker, D. I, Kirkman, H and Lethbridge, R. 1341. Perth: Western Australian Museum.  [Google Scholar]) are remarkable in possessing the head organ, a sensory structure unique to Grania that was not noted previously in Western Australian species. When considering the whole genus, the geographic pattern of the head organ appears southern‐centred: of the 17 species of Grania reported to possess it, as many as 13 inhabit the southern latitudes. The seventh species of the Esperance collection, G. vacivasa Coates and Stacey, 1993 Coates, K. A. and Stacey, D. 1993. “The marine Enchytraeidae (Oligochaeta, Annelida) of Rottnest Island, Western Australia.”. In The marine flora and fauna of Rottnest Island, Western Australia, Edited by: Wells, F. E, Walker, D. I, Kirkman, H and Lethbridge, R. 391414. Perth: Western Australian Museum.  [Google Scholar], is notable for the kind of items found in its gut and the unusual appearance of its pygidium.  相似文献   
39.
《Journal of Natural History》2012,46(17-18):993-1079
Ten new species of Brevisomabathynella Cho, Park and Ranga Reddy, 2006 Cho, JL, Park, JG and Ranga Reddy, Y. 2006. Brevisomabathynella gen. nov. with two new species from Western Australia (Bathynellacea, Syncarida): the first definitive evidence of predation in Parabathynellidae. Zootaxa., 1247: 2542.  [Google Scholar] are described and illustrated from the arid region of Western Australia. Comparison of the external morphology revealed the presence of three common characters distributed among the 10 species: the five-segmented antenna, the absence of the basipodal seta on the male thoracopod VIII and the absence of a basiventral seta on the uropodal exopod. This character combination is not found in Notobathynella and Billibathynella, but only in Brevisomabathynella, a genus known from two described species both with unusual characters. Despite the three common attributes, the 10 new species differ remarkably from these two described species, but could not be defined by their own synapomorphy. Consequently, and cognizant of a previously performed molecular analysis, we assign the 10 new species to Brevisomabathynella and amend the generic diagnosis. The species inhabit shallow aquifers in groundwater calcretes and each appears to be endemic to a given calcrete formation. The two species previously known and the 10 species now described include four sympatric species pairs, with similar-sized sympatric species differing markedly in body form. Brevisomabathynella inhabit groundwater up to at least marine salinity.  相似文献   
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