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青海东部麦区小麦条锈菌越冬调查初报
随着气候变暖及种植业结构的调整,青海省东部冬小麦的种植不断向高海拔地区扩展,为勘定小麦条锈菌在青海冬麦区的越冬情况,2008-2012年以青海省民和、乐都、尖扎、化隆、循化、贵德等地为试点,按照海拔梯度设立观测圃进行定点越冬观察.结果表明,一般年份小麦条锈菌在青海省东部地区海拔1 777~2 233 m均可越冬.不同年份间条锈菌能否越冬及越冬率的高低差异很大,当1月份平均气温在-8.0℃以下时,条锈菌在所有区域均不能越冬;当1月份平均气温在-5.0℃以上时,条锈菌能够越冬.此外,1-3月的降水量对小麦条锈菌的越冬也有影响.不同海拔地区条锈菌的越冬率存在一定差异,总趋势是海拔越低病菌越冬率越高,海拔越高病菌越冬率越低.姚强,郭青云,闫佳会,张贵,侯生英,陈万权 - 植物保护学报文章来源: 万方数据 -
上海市冬季尖音库蚊复合组现状初步研究
为研究上海市冬季尖音库蚊复合组生态学,2012年12月中旬至2013年3月中旬,在上海市7个区县(3个郊区,4个市区),每旬开展一次冬季尖音库蚊复合组调查.结果发现郊区和市区地上建筑的尖音库蚊复合组进入越冬状态,而市区地下建筑的尖音库蚊属相当一部分没有进入越冬状态,且市区地下建筑的尖音库蚊复合组吸血率与郊区和市区地上建筑越冬的蚊虫没有显著差异.周毅彬,朱江,范明秋,刘耀,张春哲,冷培恩 - 寄生虫与医学昆虫学报文章来源: 万方数据 -
中国珍奇植物:香格里拉之秋(下)
香格里拉是一个充满神秘与传奇的地方,这里蕴藏着世界上最为丰富的植物资源.香格里拉境内的地势北高南低,地形呈纵深切割之势,海拔高差极为悬殊,最高的梅里雪山海拔可达6740米,而最低谷的海拔却仅1486米,姚一麟,吴棣飞 - 园林文章来源: 万方数据 -
红景天对模拟高海拔缺氧的大鼠视网膜组织形态以及缺氧诱导因子表达的影响
目的 观察红景天对模拟不同海拔高度缺氧的大鼠视网膜组织形态以及缺氧诱导因子(HIF)表达的影响.方法 成年雌性Sprague Dawley大鼠48只随机分为干预组和对照组,每组24只.干预组大鼠按10 ml/lg的剂量腹腔注射大珠红景天注射液,对照组大鼠按相同剂量注射生理盐水.注射后1h,两组随机选取6只大鼠分别饲养于氧分压为17.6、14.7、11.3、7.4 kPa的高原环境模拟实验舱,室内模拟的海拔高度分别为1500、3000、5000、8000 m.饲养后6h摘除大鼠眼球作石蜡切片.采用苏木精伊红染色观察大鼠视网膜病理形态的改变,免疫组织化学染色观察大鼠视网膜中HIF-1α、p53的表达.分析HIF-1α与p53表达的相关性.结果 对照组大鼠视网膜各层组织水肿疏松,视网膜厚度增加,层次排列紊乱,神经节细胞肿胀变性,可见核固缩溶解及细胞数量减少;随着模拟的海拔高度增加,其视网膜病理形态改变越明显.干预组大鼠视网膜组织形态改变特点同对照组,改变程度轻于对照组.对照组大鼠视网膜中HIF-1α、p53表达主要位于神经节细胞层和内核层;随着模拟的海拔高度增加,HIF-1α、p53表达也增加.与对照组比较,干预组大鼠视网膜中HIF-1α表达增加,p53表达降低,差异均有统计学意义(P<0.05).相关性分析结果显示,HIF-1α与p53的表达呈正相关(r=0.984 6,P<0.05).结论 红景天能改善模拟高海拔缺氧所致的大鼠视网膜组织病理损害,其作用机制可能与上调HIF-1α表达、下调p53表达有关.黄海香,张文芳,杨义,独刚,顾倬 - 中华眼底病杂志文章来源: 万方数据 -
户外服装如何选
在户外运动时,驴友们面临的首要问题就是天气的变化,尤其是到一些高海拔地区,很可能在一天内经历风、雨、雹、雪4种天气的变化,因此对衣着的要求格外高,防风、透气、保暖等功能,一个都不能少.但是,在选购户外运动服装时,除了要关注其功能外,更重要的是实用.岳纲举 - 新智慧(财富版)文章来源: 万方数据 -
Space use of wintering waterbirds in India: Influence of trophic ecology on home-range size
Relationship between species' home range and their other biological traits remains poorly understood, especially in migratory birds due to the difficulty associated with tracking them. Advances in satellite telemetry and remote sensing techniques have proved instrumental in overcoming such challenges. We studied the space use of migratory ducks through satellite telemetry with an objective of understanding the influence of body mass and feeding habits on their home-range sizes. We marked 26 indi- viduals, representing five species of migratory ducks, with satellite transmitters during two consecutive winters in three Indian states. We used kernel methods to estimate home ranges and core use areas of these waterfowl, and assessed the influence of body mass and feeding habits on home-range size. Feeding habits influenced the home-range size of the migratory ducks. Carnivorous ducks had the largest home ranges, herbivorous ducks the smallest, while omnivorous species had intermediate home-ranges. Body mass did not explain variation in home-range size. To our knowledge, this is the first study of its kind on migratory ducks, and it has important implications for their conservation and management [Current Zoology 60 (5): 616-621, 2014].Tsewang NAMGAIL,John Y. TAKEKAWA,Sivananinthaperumal BALACHANDRAN,Ponnusamy SATHIYASELVAM,Taej MUNDKUR,Scott H. NEWMAN - 动物学报(英文版)文章来源: 万方数据 -
Interspecific comparison of the flight performance between sparrowhawks and common buzzards migrating at the Falsterbo peninsula: A radar study
In order to compare the two species' flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparrowhawks Accipiter ni- sus and common buzzards Buteo buteo during autumn migration. The results showed a clear difference between sparrowhawks and common buzzards in their flight altitudes and speeds, and in the wind conditions they encountered. Common buzzards had higher flight altitudes and were more selective of wind. Flight altitude was negatively related to the wind speed, which was most pronounced for common buzzards. Sparrowhawks had higher mean air- and cross-country speeds than common buzzards. Air- speed was negatively related, whereas ground and cross-country speeds were positively related to the tailwind component for both raptors. The differences between sparrowhawks and buzzards could to a large degree be explained by a larger dependence on thermal soaring among the common buzzards; a strategy associated with selectivity for favourable thermal and wind conditions during migratory flight. An additional important explanation for the interspecific differences was the habit of the sparrowhawks to combine migratory flight with hunting for prey, which makes it prone to fly at lower altitudes and use flapping flight to a much larger degree than common buzzards which do not forage during their migratory passage of the Falsterbo Peninsula [Current Zoo- logy 60(5): 670-679, 2014].Gintaras MALMIGA Cecilia NILSSON Johan BACKMAN Thomas ALERSTAM - 动物学报(英文版)文章来源: 万方数据 -
A survey for Batrachochytrium salamandrivorans in Chinese amphibians
For the last decade, chytridiomycosis was considered to be caused by a single species of fungus, Batrachochytrium dendrobatidis (Bd), but a second chytrid species, Batrachochytrium salamandrivorans (Bs), was recently isolated from an in- fected Salamandra salamandra in the Netherlands. To date, Bs has only been found in the Netherlands. To assess whether Bs is present in China, we analyzed a total of 665 samples, including 425 wild samples, 41 preserved specimens, and 199 captive sam- pies, from 30 different species, including both urodeles and anurans. Our sample sites covered 15 provinces in China. All of the samples tested negative for Bs, resulting in a 95% confidence limit for a prevalence of 0.6%. The absence of Bs observed in this large-scale survey in China has significant implications for amphibian conservation and for border trade management strategies intended to control amphibian diseases. We strongly recommend the continued close monitoring of Bs to verify the status of this potentially devastating amphibian fungus in China .Wei ZHU,Feng XU,Changming BAI,Xuan LIU,Supen WANG,Xu GAO,Shaofei YAN,Xianping LI,Zetian LIU,Yiming LI - 动物学报(英文版)文章来源: 万方数据 -
基于消除九江茶文化旅游发展成长上限的管理对策研究
一.九江发展茶文化旅游的成长上限基模系统动力学成长上限基模是研究社会管理问题的八大基模之一,成长上限基模分析法是研究系统问题的重要研究方法.成长上限基模的基本构成是一个正反馈环和一个负反馈环,负反馈环会成为抑制系统发展的制约因素,随着负反馈的制约因素的抑制作用,使得整个系统的发展逐史术光 - 农业考古文章来源: 万方数据

