办班消息

一、负责人 冉玉平教授 二、培训项目国家级医学继续教育项目《皮肤真菌病基础和临床研究新进展》[2009-04—12-060（国）]     

Fractal root system of Melica przewalskyi along different aspect in degraded grassland

Aims Fractal root system is phenotypic plasticity result of plant root architecture to respond to environmental heterogeneity, may reflect the growth strategy of plants to adapt to environmental conditions. Our objective was to explore the relationship between root fractal dimension and fractal abundance of fractal root system of Melica przewalskyi population in response to aspect variation in the northwest of China. Methods The study site was located in a degraded alpine grassland on the northern slope in Qilian Mountains, Gansu Province, China. Survey and sampling were carried out at 40 plots which were set up along four slope aspects transects with 20 m distance between adjacent plots. Handheld GPS was used to determine the elevation, longitude and latitude of each plot. ArcGIS was used to set up digital elevation model (DEM). Community traits were investigated and six individuals roots of M. przewalskyi were collected randomly at each plot. The samples were cleaned and divided into different organs, then scanning the root with the Win-RHIZO for measurements of fractal dimension and fractal abundance in laboratory, and their biomass were then measured after being dried at 80 °C in an oven. Important findings With the slope aspect turned from north to east, west, and south, the density, height and soil moisture content of the plant community displayed a pattern of initial decline, the height, density, root fractal abundance of M. przewalskyi increased and the root fractal dimension decreased. The root fractal dimension was negatively associated with the fractal abundance in all aspects, but the relationship varied along the slope aspects gradient; there was a highly significant negative correlation (p < 0.01) between the root fractal dimension and fractal abundance at north slope and south slope aspect, whereas the correlation only reached a significant level (p < 0.05) at the east slope aspect and west slope aspect; indicating that there is a trade-off between the root fractal dimension and fractal abundance. In addition, when the slope aspect changed from north to east, west and south, the standardized major axis (SMA) slope of the regression equation in the scaling relationships between root fractal dimension and fractal abundance increased (p < 0.05), indicating that the roots of M. przewalskyi at the droughty southern slope have less branch and more sparse in the same soil volume of root exploitation and utilization. Consequently, the resource allocation pattern on reasonable trade-off between root fractal dimension and fractal abundance in different slope aspect of M. przewalskyi, reflects the relationship between the income and the cost of construction of plant root architecture.     

记甘肃晚侏罗世一蜥蜴新属

本文记述石龙子类 Scincomorpha 蜥蜴的—新属,甘肃拟贝氏蜥 Mimobefklesisaurus gansuensis gen. et sp. nov. 化石发现于甘肃省肃北县马宗山区晚侏罗世的赤金堡群.这是石龙子类化石在我国的第一次发现,也是目前所发现的这类动物在亚洲的最早的代表.     

中国甘肃Eleutherophyllum Stur的新材料及其分类位置

自李星学等(1974)首次报道Eleutherophyllum waldenburgense(Stur)Zimmermann在我国发现以来,这一纳缪尔A期Eumorphoceras带的重要标志化石,除甘肃靖远大水沟外,我国其它地区至今尚无新材料增补。同时,甘肃靖远的材料,亦因标本较少和其它原因,尚未进行正式研究。近年来,为迎接     

中国菊科千里光族新植物(Ⅱ)

Yunnan(云南):Lijiang(丽江),alt、3000～3500m,ad marginem rivulae,1939-09-18,R.C.Ching(秦仁昌)30626(typus,PE) 本种叶形酷似山尖子P.haotatas(L)Y.L.Chen,但植株,特别茎上部密被腺状短柔毛;叶柄无翅,总苞片和小花均为5;冠毛褐色或紫褐色与后者明显不同。     

广东车八岭国家级自然保护区种子植物区系研究

车八岭国家级自然保护区种子植物区系种类丰富,含１６１科６４５属１３４５种（包括种下等级）,并有相当数量的古老种类和１４种珍稀濒危重点保护植物。壳斗科Ｆａｇａｃｅａｅ、樟科Ｌａｕｒａｃｅａｅ、茶科Ｔｈｅａｃｅａｅ、木兰科Ｍａｇｎｏｌｉａｃｅａｅ以及杜英科Ｅｌａｅｏｃａｒｐａｃｅａｅ、安息香科Ｓｔｙｒａｃａｃｅａｅ、全缕梅科Ｈａｍａｍｅｌｉｄａｃｅａｅ等是该区系的主要表征科,构成了其各森林类型的主要树种组成。种子植物区系成分较为复杂,主要表现在科地理成分的广泛性和属地理成分的多样性,而以热带—亚热带成分占明显的优势,热带及温带区系成分均有相当的影响,各类成分交错渗透,叠置分布。本文对车八岭国家级自然保护区植物区系的归属,广东与云南植物区系的关系等争议问题展开了讨论,认为车八岭自然保护区植物区系是中亚热带向南亚热带过渡的区系类型,为华南植物亚区的组成部分,隶属于古热带植物区。广东与云南植物区系关系密切,极可能具有同一起源（华夏植物区系）,宜划入同一植物亚区。     

甘肃双盾木属一新种

甘肃双盾木属一新种王一峰,廉永善,王国宏（西北师范大学生物系,兰州７３００７０）关键词双盾木属,文县双盾木,甘肃ＡＮＥＷＳＰＥＣＩＥＳＯＦＴＨＥＧＥＮＵＳＤＩＰＥＬＴＡＭＡＸＩＭ．ＦＲＯＭＧＡＮＳＵ￥ＷａｎｇＹｉｆｅｎｇ;ＬｉａｎＹｏｎｇｓｈａｎａｎ...     

甘肃天然药库几种主要的野生药用植物

位于甘肃省东南部的陇南地区素有天然药库、千年药乡之称。全区地处西秦岭南麓。属长江流域。地势自西北向东南逐渐低下,河流交错,峡谷幽深,沟壑纵横。年均温10～15℃,年降水量400～1000毫升,无霜期160～285天,气候属亚热带到中温带过渡区。全区有森林面积近1500万亩,森林覆盖率36％。由于独特的自然地理环境,生物资源十分丰     

建立南澳岛国家级海洋综合自然保护区的重大意义

本文从保护海洋自然生态环境、自然资源和保持物种多样性的观点出发,介绍了南澳岛的基本概况,附近海域海洋生物群落和珍稀生物概况以及闽粤著名的海鸟王国─—乌屿岛的概况。指出建立南澳岛国家级海洋综合自然保护区的重大意义;提出尽快建立南澳岛国家级海洋综合自然保护区的六条建区依据。