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《Lichenologist (London, England)》1999,31(4):319-335
Abstract: The genus Biatora is still undercollected in many parts of its distributional range. On the basis of recent collections made by the authors and additional herbarium material not studied previously, more detailed statements on the ecology, distribution and conservational status of Biatora species in Central Europe are possible. Distribution maps are provided for B. fallax , B. mendax , B. ocelliformis , B. rufidula , B. sphaeroidiza , and B. vernalis . Biatora species are almost exclusively non-saxicolous and, in general, prefer humid habitats. Many species are chionophilous and extremely shade-tolerant. Three main distributional patterns can be observed: (sub-)arctic-alpine species, sub-oceanic-montane species, and species of montane coniferous or mixed coniferous forests. Biatora efflorescens , B. flavopunctata and B. subduplex are relatively frequent species and are not threatened. Biatora rufidula and B. vacciniicola must be regarded as extinct in Central Europe. The following species are reported for the first time from the respective countries: B. chrysantha from Romania, B. efflorescens from Romania and Ukraine, B. fallax from Austria and Ukraine,B. mendax from the Czech Republic, B. ocelliformis from Romania, and B. sphaeroidiza from Germany, Austria, the Czech Republic and Romania. 相似文献
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珠江水系四大家鱼资源现状及空间分布特征研究 总被引:1,自引:0,他引:1
四大家鱼是我国淡水养殖和捕捞的主要对象, 但关于珠江水系四大家鱼资源状况的研究甚少。研究于2015—2016年对珠江全流域16个站位分春夏秋3个季节进行了全面调查, 调查的渔具主要为钩钓网、流刺网、定置刺网和虾笼。共采集四大家鱼965尾, 其中青鱼41尾、草鱼454尾、鲢351尾、鳙119尾, 均以1—2龄为主, 占所有个体的70%左右。四大家鱼主要分布于西江桂平至肇庆江段, 以及上游南盘江万峰湖库区江段。其在整个流域CPUE最高为南盘江鲁布革江段(5.68 kg); 而在中上游红水河大化、合山江段, 其资源量较低, CPUE值不足1.50 kg。重要的东江、柳江、郁江等支流, 资源量也较少, CPUE值不足2.00 kg。采用冗余分析方法(RDA)分析了四大家鱼种群空间分布格局与环境因子的关系, 发现河流等级、河流水电站总装机容量、径流量与河流深度是珠江水系四大家鱼空间分布格局差异的主要影响因子。总体上, 四大家鱼主要分布于干流, 鲢、鱅和草鱼的分布主要受径流量和河流深度的影响, 河流水电站的建设对草鱼分布的影响最大。研究结果将对渔业资源多样性保护和可持续利用具有指导意义。 相似文献
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马科在中国的分布与现状 总被引:16,自引:5,他引:16
蒙古野驴(Asinus h.hemionus)分布于内蒙和甘肃西北角、新疆东北部至准噶尔盆地西部。1982年航调,卡拉麦里山保护区内有356头,O.02头/平方公里;1986年调查为O.03头/平方公里。估计目前我国境内不超过2000头。西藏野驴(Asinus k.kiang)分布于西藏西部、新疆南缘山地;A.k.holdereri分布于除湟水河谷外青海全境、四川西北角、甘肃祁连山。1984年调查,阿尔金山保护区内有41,262头,0.917头/平方公里。估计我国境内种群约在20万头上。多年考察未发现野马(Equus przewalskii),目前可能在北塔山以东尚有少数残存。 相似文献
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Silvetia compressa ( J. Agardh) Serrão et al. is a common member of the upper intertidal fucoid community on the Pacific coast of America from Humboldt County, California, to Punta Baja, Baja California, Mexico. A relatively narrow range of morphological variability is exhibited by most mainland populations, regardless of latitude, but some mainland populations and all insular populations participate in a complex pattern that we have attempted to analyze. A few populations on the Monterey Peninsula in which the fronds are atypically delicate were described by Setchell & Gardner as f. gracilis , to which was assigned a population from Santa Catalina Island. After comparing populations from various parts of the range of the species, including all of the Channel Islands, we conclude that two subspecies may be recognized. In subsp. compressa , which includes f. gracilis as a growth form and occurs chiefly on the mainland, the frond is robust with long tapered receptacles. In the variant subspecies, which is chiefly insular but also occurs on the coast of northern Baja California, the typical frond has slender axes as in f. gracilis , but is more densely branched and has short ellipsoidal receptacles. Comparison of nucleotide sequences from the ITS regions of rDNA revealed an identical pattern for subsp. compressa from Baja California and central California, including populations assignable to f. gracilis. By contrast, the pattern for the variant subspecies differed by 2 bp (0.3%) from that of subsp. compressa. 相似文献
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The size and photosynthetic ability of Cyanidium caldarium populations in soil were related to the water status of the soil, welter soil, areas having larger populations and more extensive photosynthesis. The application of the direct methods used to the study of other soil algae, mosses, and lichens is discussed. 相似文献
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中国现代灵长类的分布、现状与保护 总被引:12,自引:4,他引:12
本文对中国现生灵长类类群分布和现状作了较全面的总结;对现存的种群数量进行了初步估价;并就保护和存在的问题与展望提出了概括性评述。所得结果系据作者自1975年以来的实际考察和国内外有关文献记载。 相似文献
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甘肃西部和中部旧石器考古的新发现及其展望 总被引:5,自引:1,他引:5
近年在甘肃西部马鬃山区的霍勒扎德盖发现了石叶,在甘肃中部的东乡族自治县发现了王家遗址等旧石器地点。这对推进中国西部旧石器考古,探索我国旧石器时代向新石器时代的过渡,开辟了前景。 相似文献
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G. W.C. Schulz 《African Journal of Aquatic Science》2013,38(1-2)
Summary A new distribution record for the South African Red Data fish species Chiloglanis bifurcus was found in the Nels River at an altitude of 830 m a.m.s.l. in the Mpumalanga province, South Africa. Previously this species was known to occur between altitudes 900 m and 1200 m a.m.s.l. in the Elands and Crocodile Rivers of the Inkomati River system, as well as in tributaries of these rivers, namely the Gladdespruit, Stadspruit and Ngodwana River. It was also found to occur in the Komati River of the same river system. 相似文献
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本工作首先应用特异性脑钠素放射免疫测定、放射受体分析和免疫组织化学的方法,研究了大鼠中枢神经系统和一些外周组织中脑钠素免疫活性物质的分布、生化特性、受体结合和生物学作用,提出脑钠素可作为一种新的神经递质或循环激素,广泛分布于体内不同组织内,并参与水电介质和心血管活动的调节。 相似文献
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江苏海岸带水域浮游动物的种类组成和分布 总被引:2,自引:0,他引:2
调查江苏海岸带水域(119°15′—123°30′E,31°40′—35°15′N),分析鉴定1980年8、11月和1981年2、5月浮游动物样品。结果如下: 1.初步鉴定浮游动物98种,其中水螅水母类29种、管水母类4种、栉水母类2种、枝角类1种、桡足类46种、糠虾类6种、磷虾类2种、樱虾类4种、浮游腹足类1种、毛颚类8种及浮游幼虫多类。 2.浮游动物的种类组成是以暖温性近岸低盐种为主的。真刺唇角水蚤。(Labidocera euchaeta)、中华哲水蚤(Calanus sinicus)、中华假磷虾(Pseudeuphausia sinica)、强壮箭虫(sagittacrassa)等是组成调查区浮游动物的主要种类。 3.浮游动物生物量,5月最高,平均达195毫克/米~3。11月最低,平均为85毫克/米~3。8月的和2月的分别为146毫克/米~3和106毫克/米~3。 4.浮游幼虫的数量,8月高最,平均达188个/米~3。2月最低,平均不到1个/米~3。5月的和11月的分别为6个/米~3和3个/米~3。 5.江苏海岸带水域能有3个全国有名的渔场存在、这和该区具有形成渔场的饵料基础——浮游动物资源丰富是分不开的。 6.不同生态类群浮游动物的时空分布基本上反映了江苏海岸带水域各个季节水文状况的基本特征。 相似文献
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三化螟(Tryporyza incertulas Walker)在赣中地区每年发生 4代,如 9月下旬至 10月上旬气温偏高(日平均气温22℃以上)则有不完整的第5代。山区则有3代幼虫过冬现象。一般1、3代为害造成枯心苗,2、4代为害造成白穗。以混栽区或纯双季稻地区发生数量大,为害严重,而单季早、中、晚稻为主地区,因其发生前后期缺乏充足食料,故发生数量小,为害亦轻。现就赣中地区近年来三化螟发生的情势及防治技术措施提出讨论如下。 相似文献
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江苏沿岸海域浮游病毒的时空分布 总被引:2,自引:0,他引:2
在2006.7—2007.12期间,采用SYBR Green I染色-荧光显微直接计数法,对江苏沿海海域浮游病毒丰度进行了四个季度的调查,同时调查还包括细菌丰度、叶绿素a浓度。浮游病毒水平分布呈现中间高,两侧低。苏北浅滩海域病毒含量最高,最高值为47.90×106个/mL;吕泗海域最低,最低值为0.03×106个/mL。季节变化表现为冬季最高,夏季次之,春秋季相当。垂直分布也变现为明显的季节变化,除秋季外,表层浮游病毒丰度高于底层水体。浮游病毒与细菌丰度比(VBR)为0.30—180.08,平均为18.35。春季浮游病毒与叶绿素a、细菌之间均存在较强的相关性,相关系数分别为0.79和0.74(P<0.01);而在秋季,浮游病毒只与细菌有较强的相关性(r=0.79,P<0.01),这说明不同季节,浮游病毒的主要宿主会发生变化。 相似文献
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R. S. Bailey 《Ibis》1968,110(4):493-519
The present paper summarises observations made during the International Indian Ocean Expedition on board the R.R.S.' Discovery, from August to November 1963 and from February to September 1964 in the Indian Ocean north of 20° S and west of 70° E. In 1963 work was carried out in the Somali Basin. In 1964 a series of transects were made over the ocean, the main purpose of which was to investigate the system of equatorial currents and the changes in the sea associated with the onset of the Southwest Monsoon in May. The Tropical Indian Ocean is briefly described. Except for local concentrations, the surface layers are poor in nutrient salts and plankton. There is a seasonal reversal of winds and surface currents in the Arabian Sea, but seasonal changes become less marked further south. Previous ornithological observations in the western Indian Ocean are mostly confined to the Arabian Sea or to the island groups. Thus, existing information on the pelagic range of pantropical species is incomplete. Observations made on each transect across the Indian Ocean in 1964 are summarised and compared with oceanographic data collected at the same time. General conclusions are not possible on the basis of so little information, though there appeared to be some relationship between the distribution of certain species and wind or current belts. The only marked discontinuity recorded was a concentration of Puffinus pacificus and Gygis alba at the northern edge of the Equatorial Counter-current at 58° E in March. Observations made on transects that were repeated before and after the onset of the Southwest Monsoon suggested that Sterna fuscata concentrates in the equatorial region as the monsoon develops. In general, both plankton and sea-birds were more abundant at 58° E than at 671/4° E. An analysis of the presence or absence of sea-birds during each observation period, which lasted an average of one hour, established the difference between pelagic species and those largely restricted to within 50 miles of their breeding stations. There was no evidence of any correlation with zooplankton abundance, though birds of all species taken together were commonest where flying-fish were most abundant and S. fuscata appeared to be commonest in cool-water areas with strong winds, i.e. the Trade-wind belts. It was not possible to sample the food organisms of sea-birds quantitatively. Sea-bird observations in the Indian Ocean more than 200 miles from the continental coasts are summarized and compared with previous observations. The little information collected in the Indian Ocean agrees with previous work in the Pacific Ocean, where sea-birds are commonest in areas of convergence, and not where local upwelling and an associated concentration of plankton occur, such as on the equator. This may be due to the fact that populations of organisms on which sea-birds feed develop or concentrate a considerable time after upwelling of nutrient-rich water occurs. Since few sea-birds were seen feeding, it seems likely that available food is scarce and that much time is required to locate areas where it is abundant. Finally, evidence is presented to indicate how some sea-bird species may avoid or reduce competition by feeding at different distances offshore, or in different geographical areas. 相似文献
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厦门附近海域浮游甲藻类的分布 总被引:3,自引:0,他引:3
本文报道了厦门附近海域浮游甲藻类49种,并对其生态特性以及与海洋环境因素的关系进行了详细研究与讨论。分析的204号样品,系1980年9月至1981年8月,逐月采自厦门海域的浔江区(Ⅰ区),西港区(Ⅱ区)和九龙江口区(Ⅱ区)。 相似文献