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本文观察了中国南极中山站越冬队员在不同季节的血压、心率、体温和体重的变化,结果表明：在极夜期间,平均收缩压低于对照和回国后的测量值;而舒张压则在极昼时高于回国后的水平;从早晨到夜间（无论极夜或极昼）血压呈逐渐升高的节律性变化。不同季节所测心率的平均值全部低于对照值,在极夜期间降到了全年的最低水平;心率在一天内的变化趋势与血压有很大的相似性。越冬队员体温的变化均低于对照值,但未达到显著的水平;就一天内不同时相而言,早晨的体温均低于其他时相。在中山站,越冬队员每月平均体重与对照值相比均有增加。上述各项生理指标变化的原因有待进一步研究。这些观察与研究为了解人体在极端环境中适应性生理功能的变化提供了基础数据。 相似文献
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研制了移动式极地大气参数测量系统。采用温度脉动仪和三维超声风速计分别对大气湍流强度C2n进行测量。在合肥和上海两地进行了约500 h的仪器性能测试,结果显示仪器运行稳定、两种方法测得的C2n符合得很好。仪器将在2013/2014年度中国第30次南极科学考察泰山站建站期间首次对泰山站的C2n进行测量、越冬期间首次对中山站的C2n进行测量,并计划在2014/2015年度第31次南极科学考察期间对昆仑站的近地面大气湍流强度进行测量。 相似文献
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南极罗斯海恩克斯堡岛(Inexpressible Island)是中国南极新建考察站重点预选区域。本文利用1988—2012年曼努埃拉自动气象站(AWS Manuela)资料统计分析了该岛的气温、相对湿度、气压和风速风向等要素的特征和变化趋势。结果表明,该岛多年平均气温为-18.5℃,年平均气温有降低趋势;多年平均相对湿度较低,仅为45%,但春夏秋冬各季节的平均湿度均有增加趋势;多年平均气压为979.7hPa,无显著变化趋势;该站点多年平均风速为12.0 m·s-1,风向以WNW为主。干冷的下降风为该岛风场的主要特征,强下降风事件多发生在冬季(49.8%),其风速在25—45 m·s-1之间,冬季单次强下降风事件的平均持续时间达10 h以上。和中山站相比,该站点气温更低、空气更干燥、风速更大,这对该岛的越冬考察活动将带来巨大挑战。 相似文献
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本研究是首次对中国南极考察队越冬预选队员进行心理选拔方法的探讨。以第十三、十四次中国南极考察队５４名越冬预选队员为对象,在冬训期间,对选拔方法的设计、实施、分析及改进作了探索,应用了艾森克人格问卷（ＥＰＱ）、行为类型问卷（ＢＰＱ）、卡特尔十六种人格因素问卷（１６ＰＦ）、自编自陈问卷、应激水平实验和直接行为观察等可供参考的选拔方案,并作了效度检验,为我国南极考察队员的选拔工作取得了初步经验,选拔方案尚待进一步完善。 相似文献
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《中国地理与资源文摘》2004,(3)
H78.53一2侧润031875南极海冰区冰燕类群及兴衰杖程=A全曰妊印ofthe iceal网~blag比曲dt城r live histo]叹in the八刀t田允tic sea-ice~/何剑锋,王桂忠…//极地研究一2003,15(2)一102一113 总结了国际上对南极冰藻类群及其生理生悉特性的多年研究成果,结合我国科学家在南极长城站以及在戴维斯和中山站的越冬研究,阐述了南极海冰区的冰裁类群及其形成机理,对冰漆的形成、存活、旺发和消亡过程进行讨论,并对大洋浮冰次和近岸面定冰区冰藻奥群的生态特性进行对比,提出了今后有待进一步深人研究的领城.图1参94 Be冰川巧34 .63、么叹娜031876第… 相似文献
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报道了中国第八次南极考察队（长城站）队员赴南极前、居留南极及回国后尿、血浆的去甲肾上腺素（ＮＥ）和肾上腺素（Ｅ）含量变化,以探讨考察队员在居留南极期间普遍存在生理和心理变化的物质基础。结果表明：考察队员到达长城站２周时尿中ＮＥ急剧增高（与赴南极前相比Ｐ＜０．０５）,越冬后（居留南极１年２周）ＮＥ大幅度下降（与到达２周时相比Ｐ＜０．００１）,考察结束回国后ＮＥ恢复到赴南极前水平。尿中Ｅ含量在到达南极２周时同样显著升高,且增高幅度大于ＮＥ（与赴南极前比较Ｐ＜０．００１）,越冬后Ｅ水平比到达２周时有所降低（Ｐ＜０．０５）,回国后Ｅ水平没有恢复。提示,儿茶酚胺变化参与综合应激反应过程,Ｅ受心理影响大于生理因素。还发现部分考察队员惧怕抽血,故测定尿儿茶酚胺含量更切实可行。经酸化处理的尿样品在短期内温度（室温）对儿茶酚胺含量影响不大,因此,从南极实地取样返回国内检测及进行南极医学方面的研究完全可行。 相似文献
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E. Schlecht U. Dickhöfer M. PredotovaA. Buerkert 《Journal of Arid Environments》2011,75(11):1136-1146
Goat husbandry in Oman’s Hajar Mountains supplies income and manure to farmers. An earlier analysis concluded that it uses purchased feeds inefficiently, but did not value the contribution of mountain pastures to goat nutrition and cropland fertilization. Therefore intake of pasture vegetation, cultivated forages and purchased feeds was determined in goats from three villages in spring and autumn 2005. Faecal excretion was quantified using TiO2 and diet digestibility was calculated from faecal nitrogen (N).Organic matter (OM) intake varied from 71 to 107 g kg−0.75 d−1. Pasture vegetation supplied 45-71% of OM intake, and at least 28%, 33% and 42% of phosphorus (P), metabolizable energy (ME) and N intake. While ME intake just covered maintenance and locomotion requirements, N and P intake exceeded the animals’ requirements. Therefore faecal concentrations (g kg−1 OM) of 26-36 g N and 4-8 g P were high, making goat dung a key element of sustainability for the local cropping systems.Since mountain pastures supply nutrients to goats and cropland, their long-term productivity is crucial. Feeding cultivated forages seemingly reduces intake on pasture, but a comprehensive evaluation of nutritional and economic implications of this strategy and possible alternatives is needed. 相似文献
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中国饮食文化地理研究综述 总被引：3，自引：0，他引：3
饮食文化是人们在日常生活中饮食行为、习惯和环境的时间沉积与空间相互作用的积累,主要包括食物本身的属性,制作过程和仪式,用餐的器具、环境、礼仪和风俗等。作为人类文化的一部分,饮食文化正日益受到国内外学者们的关注。通过对文献的统计、收集与分析,从中国饮食文化的基本概念和性质出发,以人地关系为主线对饮食文化的地理区域分异、地理环境对饮食文化的影响、饮食文化的发展趋势和饮食文化资源的开发与利用等几个方面进行概述,并在此基础上总结出当前学术界对中国饮食文化的研究成果。 相似文献
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L.S. Jaber 《Journal of Arid Environments》2011,75(7):625-628
The current study was designed to assess the effect of water restriction on fat metabolism in Awassi ewes orally supplemented with different levels of vitamin C. Experiment 1 (24 days) included four groups, four animals in each, with one group as control receiving daily water. The three remaining groups were watered once every four days, with the third and fourth groups receiving a daily oral dose of 3 g and 5 g vitamin C, respectively. Experiment 2 (21 days) was similarly designed except that the last group was administered one 10 g vitamin C oral dose at the beginning and at the middle of the experiment. Water restriction induced a reduction in feed intake and consequently weight loss in both experiments. Fat cell diameter, insulin, leptin, T3 and T4 concentrations tended to decrease in water restricted animals with or without vitamin C, while fatty acids and cholesterol increased. The observed changes reflect fat mobilization in water restricted Awassi ewes, which seemed to be correlated with insulin and leptin levels. Furthermore, fat mobilization reflected by high fatty acid and low leptin concentrations seemed to be more enhanced by daily supplementation of vitamin C than by the singular high dosages repeated twice, however further research is needed to confirm this observation. 相似文献
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壤塘县大骨节病病区环境中硒的分布特征 总被引：3，自引：1，他引：2
大骨节病是一种地方性骨关节病,主要分布于环境低硒地区。目前,我国大部分地区大骨节病病情已经得到控制,病情相对活跃而严重的区域主要集中于青藏高原地区。四川省壤塘县地处青藏高原东南缘,大骨节病遍布全县各村且最低患病率不低于13.28%。本文选择不同病区采集了耕作土壤(0~20cm)、青稞、糌粑和饮用水等样品,并分析了样品含硒量与大骨节病病情的关系。结果表明：壤塘县大骨节病病区环境含硒水平很低,特别是病情比较严重的村子其环境含硒水平更低。耕作土壤和青稞籽粒含硒水平依次为中病区>重病区>极重病区。受制作过程中添加物的影响糌粑含硒水平为中病区>重病区≈极重病区。虽然不同饮水类型硒的水平存在差异,但是,极重病区饮用水中含硒量也低于中病区和重病区。大骨节病与当地环境因素特别是主要粮食和食物含硒量的关系非常密切。在低硒环境条件下,由于饮水仅对人体硒的摄入起辅助性的作用,因此,调节和改善环境低硒地带居民的膳食结构,增加外源性高硒食物的输入,减少人体对低硒环境因素的依赖性,将会对大骨节病的防治具有重要的意义。 相似文献
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流动性语境中,流动群体因其承载的源地文化基因与在地饮食文化的碰撞,不可避免地陷入维系源地饮食与融入在地饮食的两难境地,从而引发了饮食调适与身份焦虑等问题。尽管学界探讨了流动群体在不同饮食文化影响下的调适策略,但大多将固守源地文化与接纳在地文化进行对立,忽视了个体能动的协商过程。论文基于文化地理学视角,以广州流动群体为研究对象,分析他们在跨地方饮食适应过程中采取的多元策略及身份协商。研究发现,在不同地方饮食文化的影响下,流动群体跨地方饮食适应的策略包括饮食同化、饮食融合、饮食隔离与饮食边缘化。在不同策略之下,流动群体的日常饮食实践呈现出差异化的特征,并使得原本单一的源地身份认同趋于复杂化。论文提出了跨地方饮食适应的分析框架,讨论了饮食适应的多元策略与身份协商之关系,为文化地理学视角下的移民与饮食研究提供了新的理论视野,在实践层面上有利于促进流动群体的饮食适应与社会融入。 相似文献
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西藏林周县是我国大骨节病(KBD)患病较为严重的地区之一,本文将林周县作为研究区,通过使用地理探测器(GeoDetector)量化分析KBD患病率风险因子的影响,并使用环境化学方法验证空间分析结果。通过对10个潜在影响因子的分析以及对当地KBD患病村和非患病村的土壤-水-粮食-人这一生物地球化学循环的环境化学分析,结果表明:(1)林周县KBD由一组多重且交互作用的环境影响因子共同作用影响,其中最重要的控制因子是地层因子;(2)所有环境介质(土壤、水、谷物)及人体组织中的硒元素浓度在KBD患病区均低于非患病区;(3)当地居民对硒和铬的摄入严重不足,尤其是KBD患病村中居民硒元素平均日摄入量(ADD)大约仅为世界卫生组织(WHO)建议的成人基本摄入量下限的4%;(4)我们推测,当地居民患病主要是由于地层这一影响因子,这是由于通过生态系统的迁移转化导致当地人口严重硒缺乏,最终导致地方性生物地球化学硒缺乏。 相似文献
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Inter- and intraspecific variations of the chemical properties of high-Arctic mosses along water-regime gradients 总被引：1，自引：1，他引：0
We examined and compared the contents of organic chemical components (lignin-like compounds, total carbohydrates and extractives), carbon and nutrients (nitrogen, phosphorus, potassium, calcium, magnesium) among the mosses Calliergon giganteum, Hylocomium splendens, Racomitrium lanuginosum, and among three populations of H. splendens collected from habitats in contrasting water regimes in the Canadian high-arctic tundra. C:N:P ratios were analyzed among and within moss species. Mosses from hydric habitats had lower total carbohydrate and higher nutrients contents than did mosses from drier habitats; however, we found no intraspecific variations in nitrogen and calcium contents in the different populations of H. splendens along water-regime gradients. The contents in lignin-like compounds, extractives and carbon showed no clear trends along water-regime gradients. Mosses from hydric habitats had lower C:N, C:P and N:P ratios than mosses from drier habitats, although we found no intraspecific variations in C:N ratios in H. splendens along water-regime gradients. These results suggest that chemical properties of mosses, especially nutrient contents, are strongly correlated with water availability in high-Arctic tundra. 相似文献
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Exploring the utilization effect of water-land resources under the evolution of dietary patterns is of great significance in achieving sustainable global food consumption and the effective allocation of national resources. Our selected study area was China, a country with rapidly changing dietary consumption patterns, and the research period was between 1987 and 2020. Based on the material called Chinese Dietary Guidelines 2021, this study introduced the “virtual water” and the “virtual land” to... 相似文献
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Measurements and Models of the Mass Balance of Hintereisferner 总被引：1，自引：0，他引：1
M. Kuhn E. Dreiseitl S. Hofinger G. Markl N. Span & G. Kaser 《Geografiska Annaler: Series A, Physical Geography》1999,81(4):659-670
This paper summarizes the methods applied to determine the mass balance of Hintereisferner and several other glaciers in the Tyrolean Alps since 1952. On an annual basis the direct glaciological method was applied with fixed date measurements on 10–15 accumulation pits and 30–90 ablation stakes on 9 km2 .
Indirect mass balance determination from equilibrium line altitude, accumulation area ratios or representative stakes, yield fair results and some exceptions could be related to anomalous meteorological conditions.
Monthly or more frequent stake readings supplied time series of ablation at various altitudes and slope aspects that served as basis for the calibration of energy and mass balance models. Of various models developed, two are presented in this paper. Both are based on degree days, one using daily values from a valley station to predict the mean annual balance of the entire glacier, while the other calculates day-to-day changes at 50-m grid points on the glacier.
The geodetic method has been applied for longer periods and yields results consistent with those of the glaciological method. The balance velocity calculated from recent ice thickness soundings and accumulation measurements is significantly less than observed velocity. 相似文献
Indirect mass balance determination from equilibrium line altitude, accumulation area ratios or representative stakes, yield fair results and some exceptions could be related to anomalous meteorological conditions.
Monthly or more frequent stake readings supplied time series of ablation at various altitudes and slope aspects that served as basis for the calibration of energy and mass balance models. Of various models developed, two are presented in this paper. Both are based on degree days, one using daily values from a valley station to predict the mean annual balance of the entire glacier, while the other calculates day-to-day changes at 50-m grid points on the glacier.
The geodetic method has been applied for longer periods and yields results consistent with those of the glaciological method. The balance velocity calculated from recent ice thickness soundings and accumulation measurements is significantly less than observed velocity. 相似文献
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Abundance and diversity of fungi in relation to chemical changes in arctic moss profiles 总被引：1，自引：1，他引：0
Mosses are a dominant component of high-arctic terrestrial ecosystems, yet little is known regarding the abundance and diversity of fungi associated with these abundant plants. We investigated vertical patterns of abundance and diversity of fungi and their relationship with chemical properties within profiles of Hylocomium splendens and Racomitrium lanuginosum collected in the Oobloyah Bay area on Ellesmere Island, Canada. The moss profiles were divided into 6 (H. splendens) and 5 (R. lanuginosum) layers according to the color and texture, and hyphal length, fungal assemblages, and contents of organic chemical components (acid-unhydrolyzable residues, total carbohydrates, extractives) and nutrients (N, P, K, Ca, Mg) were measured. Total hyphal length was greatest at the middle layers of H. splendens and at the deepest layers of R. lanuginosum and was significantly affected by moss species and nutrient contents. A total of 18 and 19 fungal taxa was isolated from the profiles of H. splendens and R. lanuginosum, respectively, with 11 taxa being common to both moss species. Moss species significantly affected the species distribution of fungi. Individual fungal taxa showed patterns of vertical distribution within the moss profiles. The contents of acid-unhydrolyzable residues and nutrients increased and the content of total carbohydrates decreased down the profile, which was attributable to the ability of fungi to decompose carbohydrates selectively and to immobilize nutrients in decomposed moss residues. 相似文献