木材与年轮 早材( ear lywood 年轮 心材年轮界早材晚材 横切面 晚材(| atwood 径向切面 心材〔 heartwood 射线 树皮 边材( sapwood 切向切面 杨树茎三切 面
木材与年轮 早材(earlywood) 晚材(latewood) 心材(heartwood) 边材(sapwood)
Multi-Media Data Repository Subscribe FeedbackHelp Search GSA PublicationsGo GSA Journals Online Access Control Volume 36, Issue 2(February 20D The article you have requested is available via Journal Subscription, single Al Free Abstract] Article: pp 99-102 I Abstract I PDF (697K) Annual patterns within tree rings of the arctic middle Ma): Isotopic signatures of precipitation, relative hun deciduousness A Hope Jahren and Leonel S.L. stember 1. Department of Earth and Planetary Sciences, Johns Hopkins University Baltimore, Me Department of Biology, University of Miami, Coral Gables, Florida 33124, USA The spectacular preservation of middle Eocene(ca 45 Ma) wood allows for intraseas (paleolatitude 78.8+1.6"N; present latitude 80.N). Carbon isotopes in bulk organid striking annual patterms interpreted as the seasonal switchover from stored to activel associated with deciduous growth in these unusual conifers. Oxygen and hydrogen Insider cellulose and cellulose nitrate allow for the calculation of changes in relative humidity Diae outh of NZ, p. 119 of plant-available water. Clear annual patterns of increasing relative humidity resu tin Foraminiferal, Lipids, and Cellulose: An Eocene Trilogy, Pp.99,147.179 concomitant transpiration are apparent, as is the systematic increase in the recons Cambrian Mollusks Really do Grow Up, p.175 value of environmental water, refecting progressively increasing temperatures during Discharge and Retreat-The Showdown in Gower Gulch, P.187 Keywords: Eocene, Arctic, Metasequoia, relative humidity, deciduousness, tree ring
实验要求 1.了解双子叶植物茎初生结构及次生加粗过程。 2.了解单子叶植物禾本科茎初生结构。 3学习徒手切片法
1.了解双子叶植物茎初生结构及次生加粗过程。 2.了解单子叶植物禾本科茎初生结构。 3.学习徒手切片法。 实验要求
实验内容: 1)观察挂图 2)观察切片:苜蓿茎横切面 玉米茎横切面 椴树茎横切面 松树茎横切面 3)制作并观察临时装片:紫菜苔
1）观察挂图 2）观察切片：苜蓿茎横切面 玉米茎横切面 椴树茎横切面 松树茎横切面 3）制作并观察临时装片：紫菜苔 实验内容：
苜蓿茎横切面
苜蓿茎横切面