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61.
Andrés Camou-Guerrero Victoria Reyes-García Miguel Martínez-Ramos Alejandro Casas 《Human ecology: an interdisciplinary journal》2008,36(2):259-272
We used a quantitative ethnobotanical approach to analyze factors influencing the use value of plant species among men and
women of the Rarámuri people in Cuiteco, Chihuahua, Mexico. We constructed a use value index (UV) combining the use frequency
(U) and the quality perception (Q) of useful plant species by local people. We identified all plant species used by the Rarámuri and classified them into 14
general use categories. We interviewed 34 households in the village to compare men and women’s knowledge on the five main
general use categories (and on their respective subcategories and specific uses), to document how they practice gathering
activities and to calculate scores of plants UV. A total of 226 useful plant species were identified, but only 12% of them
had high UV scores for the 42 specific uses defined. When the overall knowledge of plant species was examined, no significant differences
were detected between men and women, but significant differences were identified in general use categories such as medicinal
plants, plants for construction and domestic goods, but not in plants used as food and firewood. We identified a division
of labor in gathering activities associated with gender, with women mainly gathering medicinal and edible plants and being
involved in preparing medicines and food, whereas men were primarily gathering and using plants for manufacturing domestic
goods, firewood, and building materials. Plant species UV associated to gender were significantly different between men and
women at the level of specific uses in the general category of domestic goods and building. Frequency of use is highly associated
with plant species quality perception. 相似文献
62.
研究了29种柳属( Salix )植物在扫描电镜下的叶表皮微形态特征.结果表明:柳属的角质层蜡质纹饰可以划分为:痂状蜡质层,壳状平滑蜡质层,具凸起颗粒的蜡质层,具颗粒的蜡质层,锥形纤维体和鳞片状纤维体6种类型.其中锥形纤维体和鳞片状纤维体均为柳属所特有的蜡质类型,后者为前者的变型,这两种蜡质纹饰类型多见于较为进化的皱纹柳亚属和黄花柳亚属,故推测其可能为柳属中较为进化的性状.研究还发现气孔有外拱盖扁平和隆起呈脊状2种类型.而气孔外拱盖内缘为浅波状的类型仅见于高山和北极的类群中,因而推测该类型可能同高山和极地的低温等环境有关.气孔外拱盖的形态及其角化的情况以及蜡质类型是稳定的鉴别特征,对于柳属植物,尤其是一些表型相似的种类有很好的鉴别作用,但对于组、亚属的界定作用不大. 相似文献
63.
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65.
沙地柏叶型变化的生态意义 总被引:12,自引:1,他引:11
沙地柏(Sabina vulgaris)的叶包括刺叶和鳞叶两种类型。本文探讨沙地柏刺叶与鳞叶的结构和功能差异的生态意义。结果表明:(1)刺叶的角质层厚度、表皮细胞大小、叶肉细胞表面积和维管束大小都显著小于鳞叶;(2)刺叶的组织密度和失水系数都明显大于鳞叶;(3)刺叶的净光合速度、蒸腾速率和胞间CO2/大气CO2比都显著大于鳞叶,而前者的水分利用效率显著低于后者。这些结果指示:沙地柏刺叶的光合产物积累和水分丧失量大于鳞叶,但前者的抗旱保水性、耐辐射能力和水分利用效率都低于后者。刺叶和鳞叶的结构和功能差异表明:沙地柏叶型变化在一定程度上具有适应意义。 相似文献
66.
山东章丘上新世巴漏河组和更新统孢粉植物群 总被引:3,自引:0,他引:3
山东章丘巴漏河组和上覆更新统孢粉植物研究表明,当地上新世植物群的分布类型趋于单调,草本植物和部分广布型植物繁盛;更新世植物群的成分变得更加贫乏,其中,第三纪常见的喜暖类型已全部消失,而广布型植物类型得以进一步发展。植物群所反映的气候较中新世趋于干冷,与我国华北地区晚第三纪以来植物群的总体发展规律相一致。巴漏河组在层位上与临朐和昌乐等地的尧山组相对比,当前研究表明,以往报道的尧山组底部沉积夹层中的孢粉组合,其时代与山旺组相接近,而不同于巴漏河组;孢粉证据支持将其归于山旺组的划分意见。通过比较,建立巴漏河组与山东北部钻孔剖面明化镇组上段孢粉组合的对比比较。 相似文献
67.
繁缕和无瓣繁缕六个居群的数值分析 总被引:6,自引:0,他引:6
对繁缕(Stellaria media)和无瓣繁缕(S.apetala)的6个居群的57个性状进行Q-聚类和R-聚类的研究。结果表明:(1)Q-聚类中,用一条结合线,可以把繁缕的4个居群聚为一类,无瓣繁缕的2个居群聚为一类。这一结果支持肥繁缕和无瓣繁缕划分为两个物种;(2)R-聚类中,发现了呈现完全正相关、极大正相关和极大负相关的性状,并根据R-聚类的结果,运用一条适当的结合线,把繁缕和无瓣繁缕的57个性状划为5个类群,并分析了各性状的分类学意义。 相似文献
68.
69.
ANASS TERRAB JUAN L. GARCÍA-CASTAÑO JOSE M. ROMERO REGINA BERJANO CLARA DE VEGA SALVADOR TALAVERA 《Botanical journal of the Linnean Society. Linnean Society of London》2007,155(1):49-56
Nectar samples were collected from Silene colorata Poiret (Caryophyllaceae), in three different populations from south-western Spain: Zahara de la Sierra (Cádiz), Bornos (Cádiz) and Bormujos (Seville). Samples were analysed for amino acids by reverse-phase high-performance liquid chromatography with precolumn phenylisotiocyanate (PITC) derivatization. The method has the advantage of being highly sensitive, capable of detecting nanogram (ng) quantities of amino acids. Eighteen amino acids were identified and quantified. The mean number of amino acids in a nectar sample was 14 (SD = 2.8). Six amino acids (threonine, alanine, arginine, proline, tyrosine and methionine) were detected in all samples, accounting for 83% of the total amino acids content; proline and arginine were the most abundant amino acids, accounting for 40% and 20% of the total amino acids, respectively. The mean amounts of amino acids in nectar samples per population were 824, 782 and 356 µ m in Zahara de la Sierra, Bornos and Bormujos, respectively. Environmental variations such as temperature and sunlight are factors influencing the metabolic processes of nectar production. Our results may contradict the theory that the chemical constituents of floral nectar vary according to the kinds of pollinators. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 49–56. 相似文献
70.
P. Bauer 《Biometrical journal. Biometrische Zeitschrift》1987,29(8):895-906
Based on the concept of the multiple level of significance two criteria for assessing the performance of multiple tests are proposed: The simultaneous power is defined as the probability of rejecting all false null hypotheses. The probability of a correct decision is defined as the probability of correctly rejecting all false null hypotheses and accepting all true ones. Both criteria are discussed for nonstagewise and stagewise procedures in case of independent test statistics. For the example of 5 independently and normally distributed test statistics the values of the two criteria are calcutated under reasonably simple alternatives. 相似文献