5 resultados para Barata, Ruy, 1920-1990. O nativo de câncer - Crítica e interpretação

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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“Dissolved” (< 0.4 μm filtered) and “total dissolvable” (unfiltered) trace element samples were collected using “clean” sampling techniques from four vertical profiles in the eastern Atlantic Ocean on the first IOC Trace Metals Baseline expedition. The analytical results obtained by 9 participating laboratories for Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb, and Se on samples from station 4 in the northeast Atlantic have been evaluated with respect to accuracy and precision (intercomparability). The data variability among the reporting laboratories was expressed as 2 × SD for a given element and depth, and was comparable to the 95% confidence interval reported for the NASS seawater reference standards (representing analytical variability only). The discrepancies between reporting laboratories appear to be due to inaccuracies in standardization (analytical calibration), blank correction, and/or extraction efficiency corrections.Several of the sampling bottles used at this station were not adequately pre-cleaned (anomalous Pb results). The sample filtration process did not appear to have been a source of contamination for either dissolved or particulate trace elements. The trace metal profiles agree in general with previously reported profiles from the Atlantic Ocean. We conclude that the sampling and analytical methods we have employed for this effort, while still in need of improvement, are sufficient for obtaining accurate concentration data on most trace metals in the major water masses of the oceans, and to enable some evaluation of the biogeochemical cycling of the metals.

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基于2473个土壤剖面资料和1980年代末~1990年代末陆地卫星TM影像分析中国1990~2000年林地、草地、耕地之间的土地利用变化对土壤碳氮蓄积量的影响。IPCC建议的国家温室气体清单方法计算表明从1990~2000年中国林地、草地、耕地土壤(30cm)有机碳氮库分别损失了77.6±35.2TgC(1Tg=106t)和5.6±2.6TgN,年均损失约7.76TgC/yr和0.56TgN/yr,其中耕地土壤碳库分别增加了79.0±7.7TgC和9.0±0.7TgN,草地土壤碳氮蓄积量分别损失了100.7±25.9TgC和9.8±2.2TgN,林地土壤碳氮蓄积量分别损失了55.9±17.0TgC和4.9±1.1TgN。同时根据中国6大行政区林地、耕地和草地之间的相互转换面积、土壤有机碳氮密度的变化率进行估算,表明土壤(30cm和100cm)有机碳氮蓄积量分别损失了53.7TgC、5.1TgN和99.5TgC、9.4TgN。由于中国不同地区土地利用变化的空间格局差异显著,从而导致东北地区土壤碳氮蓄积量变化较大,而华东地区变化较小。

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Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. Supported by the dynamic serving system of national resources, including both the environment database and GIS technology, this paper analyzed the land-use change in northeastern China in the past ten years (1990 - 2000). It divides northeastern China into five land-use zones based on the dynamic degree (DD) of land-use: woodland/grassland - arable land conversion zone, dry land - paddy field conversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamation and abandoned zone. In the past ten years, land-use change of northeastern China can be generalized as follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and 276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residence increased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of 1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4 and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns of land use, this paper also discusses the driving forces in each land-use dynamic zones. The study shows that some key biophysical factors affect conspicuously the conversion of different land- use types. In this paper, the relationships between land- use conversion and DEM, accnmlated temperature(>= 10 degrees C) and precipitation were analysed and represented. We conclude that the land- use changes in northeast China resulted from the change of macro social and economic factors and local physical elements. Rapid population growth and management changes, in some sense, can explain the shaping of woodland/grassland - cropland conversion zone. The conversion from dry land to paddy field in the dry land - paddy field conversion zone, apart from the physical elements change promoting the expansion of paddy field, results from two reasons: one is that the implementation of market-economy in China has given farmers the right to decide what they plant and how they plant their crops, the other factor is originated partially from the change of dietary habit with the social and economic development. The conversion from paddy field to dry land is caused primarily by the shortfall of irrigation water, which in turn is caused by poor water allocation managed by local governments. The shaping of the reclamation and abandoned zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of fanning than that of pasturing in the interlocked zone of farming and pasturing. In northeastern China, the rapid expansion of built-up areas results from two factors: the first is its small number of towns; the second comes from the huge potential for expansion of existing towns and cities. It is noticeable that urban expansion in the northeastern China is characterized by gentle topographic relief and low population density. Physiognomy, transportation and economy exert great influences on the urban expansion.

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异毛虫科(Paraonidae)和海稚虫科(Spionidae)是环节动物门(Annelida),多毛纲(Polychaeta)中两个常见的科,其成体在海洋生态系统尤其是海洋底栖动物群落中占有重要地位。中国近海异毛虫科和海稚虫科种类极为常见,在潮间带和潮下带均有分布。但由于此两科种类个体小,采集和鉴定困难,在中国一直没有系统的分类学研究。 本论文选择异毛虫科和海稚虫科为研究对象,以中国科学院海洋研究所海洋生物标本馆馆藏的3000余号成体标本为主要研究材料,结合攻读博士学位期间对全国各海域的补充采集标本和从其它单位借用的标本,在认真阅读相关文献和比对某些种类模式标本的基础上,首次对此两科的中国种类进行了全面系统的分类学和地理分布研究。结果如下: 1. 本文记述了中国海域异毛虫科4属18种,其中包括3新纪录种;海稚虫科16属39种,包括7新种,10新纪录种。各鉴定种类均进行了详细的分类学特征描述,并附有形态学结构图。对罕见种类的标本和保存状况较差、光学显微镜无法获得可靠分类学信息的标本进行了扫描电镜观察,并拍摄有电镜照片。 2. 对中国海域有关异毛虫科和海稚虫科种类记录进行了系统的分类学修订,澄清了部分种类特别是一些常见种类分类学研究中存在的错误和混淆。(1)通过大量阅读文献和反复比较检查标本,认为以前我国文献记录的海稚虫科奇异稚齿虫属的奇异稚齿虫Paraprionospio pinnata (Ehlers, 1901)实际包括3种,即扭鳃奇异稚齿虫Paraprionospio inaequibranchia (Caullery, 1914)、枫香树奇异稚齿虫Paraprionospio coora Wilson, 1990和冠奇异稚齿虫Paraprionospio cristata sp. nov.,其中扭鳃奇异稚齿虫和枫香树奇异稚齿虫在中国海属首次记录,冠奇异稚齿虫为一新种。枫香树奇异稚齿虫主要分布于黄海,其分布南界为121°30′ E, 34°30′ N, 扭鳃奇异稚齿虫分布于南海,其分布北界为114°00′ E, 21°45′ N,冠奇异稚齿虫分布区域较广,从长江口到南海的沿岸水域均有分布。奇异稚齿虫是分布在智利、南加利福尼亚、西墨西哥(可能还有安哥拉)的种,在我国海域未见分布。(2)将在我国北方沿海非常常见但长期被记录为鳞腹钩虫Scolelepis (Scolelepis) squamata (Müller, 1806)(海稚虫科)的标本重新鉴定为一个新种,即红纹腹钩虫Scolelepis (Scolelepis) daphoinos sp. nov.;鳞腹钩虫分布于北大西洋和地中海沿岸水域,在我国海域未见分布。(3)明确了中国海Prionospio steenstrupi复合体种类。此复合体所包含的种类在形态上十分相似,分类学研究时极易混淆。在已有的文献记录中,该复合体中国种类包括两种,玛氏稚齿虫Prionospio (Prionospio) malmgreni Claparède, 1870和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。本文将该复合体中国种类修正为5种,分别是包氏稚齿虫Prionospio (Prionospio) bocki S&ouml;derstr&ouml;m, 1920、开普敦稚齿虫Prionospio (Prionospio) dubia Maciolek, 1985、太平洋稚齿虫Prionospio (Prionospio) pacifica sp. nov.、欢乐稚齿虫Prionospio (Prionospio) paradisea Imajima, 1990和西沙稚齿虫Prionospio (Prionospio) sishaensis Wu & Chen, 1964。现在大多数分类学者认为玛氏稚齿虫是一个不可鉴定种,该种的原始描述可能包括数种,且模式标本已丢失。(4)将中国海记录的矮小离稚齿虫Apoprionospio pygmaea (Hartman, 1961)更正为卡米拉离稚齿虫Apoprionospio kirrae Wilson, 1990;将中国海记录的科氏光稚虫Spiophane kroyeri Grube, 1860更正为深蓝光稚虫Spiophanes fuscatus sp. nov.。 3. 比较研究了中国海域异毛虫科和海稚虫科的区系特点,详细分析了两科中国海种类的组成。认为中国种类在区系组成上属于印度-马来区系,异毛虫科中国海特有种较少,仅2种,占该科中国种数的11%;而海稚虫科中国海特有种较多,共9种,占该科中国种数的23%。中国海异毛虫科种类组成和日本、俄罗斯附近水域的组成较为相似,中国海海稚虫科种类组成和日本、澳大利亚附近水域的组成较为相似。

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Nine species of Prionospio complex are recorded front China's waters, including one new species and six newly recorded species. Prionospio (Prionospio) pacifica sp. nov., is characterized by having first and forth pairs of branchiae pinnate, second and third pairs of apinnate, ventral crest on Setiger 9 and dorsal crests on Setigers 10-25. Apoprionospio kirrae (Wilson, 1990), Prionospio (Aquilaspio) convexa Imajima, 1990, Prionospio (Minuspio) multibranchiata Berkeley, 1927, Prionospio (Prionospio) bocki Soderstrom, 1920, Prionospio (Prionospio) dubia Maciolek, 1985 and Prionospio (Prionospio) paradisea Imajima, 1990 are recorded for the first time from China's waters.