988 resultados para 147-895C


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The commercial landings of fish in three areas of the Kafue Floodplain were examined in regard to thhing technique used, catch per unit effort, and species composition and length size. Gillnets were used throughout the year although predominantly in the wet season, and drawnets (similar to beach seines) were used at periods of low water level. Fishermen used a varying number of gillnets in each area, and the catehes also varied according to month. Principal species caught on the floodplain were clarias gariepinus and Tilapia andersoni. There are indications that, whereas the catch per gillnet in the year's 1965-1970 may be lower than in the 1950s. The drawnet calch per unit of effort of these later years is higher than in the 1950s.

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The paper examines a conceptualized fishing system for the African Environment with a comparative approach. Although the fishing system has been conceived as a bio-economic complex, emphasis will be given to the explanation of the detailed structure and functioning of the system. Subsequent synthesis involving the use of existing relationships for management etc. will also be undertaken. The proposed fishing system is conceptually feasible in an ideal environment with adequate monitored data and organized fishing, however it is anticipated that the African environment will not satisfy such conditions.

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 从腾冲热海分离到最高生长温度达70 ℃的1 株嗜热非芽孢菌RH9901 菌株,鉴定为玫瑰亚栖热菌 新种( Meiothermus rosaceus) 。对其所产色素进行吸收光谱扫描及薄层层析分析表明为类胡萝卜素。振荡培 养在菌体生物量和色素产量上均高于静置培养,培养至50 h 菌体生长量和色素产量达到最大值,菌体色素产 量为1. 147 mg/ g 干重。

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云南是我国生物多样性丰富的地区, 在生物多样性保护中扮演着重要角色而云南国家 级自然保护区在云南省自然保护区中又拥有较大比重, 分布在云南生物多样性关键地区, 对多 种生态系统和大量动植物的保护起到了至关重要的作用。经过多年的努力, 一些重要珍稀濒危 动物种群数量有所增加。但这些保护区仍然存在一系列问题, 主要包括三方面, 一是客观因 素, 大多数保护区地处边远落后山区二是来自于周边村寨巨大的人口压力三是来自于当地 政府和保护区, 主要是缺乏长远规划、大力投资等问题。保护区资源受到如此多种因素的威 胁, 保护效果得不到充分发挥。只有采取强有力的保护措施, 如加强社区共管、拓宽投资渠 道、进行科学规划管理等, 才能使保护区走上可持续发展的轨道。

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:报道了云南短翼蚱科一新属和一新种:冠顶蚱C.a/yptraeus新属,勐腊冠顶蚱C.meng/aens/5新种。

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Nomascus亚属有3个有效种附8个亚种。白颊长臂猿H. leucogenys, 为单型种。红颊长臂猿H. gabriellae有2个亚种; 黑冠长臂猿H. concolor有6个亚种。并介绍了种的分布地。图1表3参10

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Rhesus macaques and stump-tailed macaques are sympatric in western Yunnan (China), coexisting or occupying habitats that show little difference. This paper tests hypotheses based on theoretical expectation from the differing biomechanical demands of terrestrial and arboreal quadrupedalism in stump-tailed macaques and rhesus macaques, respectively. Individuals of these two macaque taxa were markedly separated by the first two principal components and discriminant analyses based on 18 variables of the upper limb. The rhesus macaques appear to be more adapted for arboreal quadruped habits because of elongation of the clavicle and forearm, a larger humeral head and greater midshaft sagittal diameters of the radius and ulna.

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1 It has not been uniform to date that the Ginkgo biloba extracts enhance cognitive function in aged animals, and the mechanisms of action remain difficult to elucidate. In this study, the Morris water maze task and electrophysiological methods were used

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