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应用rioja软件包建立有壳变形虫-环境因子转换函数 被引量:12
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作者 李鸿凯 李微微 +3 位作者 蒲有宝 王从洋 王松梅 杨晓林 《地理科学》 CSCD 北大核心 2013年第8期1022-1028,共7页
应用R语言rioja软件包的加权平均(Weighted Averaging,WA)和加权平均偏最小二乘(Weighted AveragingPartial Least Squares,WA-PLS)模型建立了长白山区泥炭藓泥炭地有壳变形虫与水位埋深(depth to water table,DWT)、pH和泥炭湿度的转... 应用R语言rioja软件包的加权平均(Weighted Averaging,WA)和加权平均偏最小二乘(Weighted AveragingPartial Least Squares,WA-PLS)模型建立了长白山区泥炭藓泥炭地有壳变形虫与水位埋深(depth to water table,DWT)、pH和泥炭湿度的转换函数,为古环境定量重建奠定了基础,也提供了rioja软件包应用的实例和参考。结果表明水位埋深以WA-PLS模型最佳(预测均方根误差RMSEP为7.39 cm,R2=0.74);对于pH和泥炭湿度,WA-PLS第一分量和WA.inv都产生了最小的RMSEP和较高的R2值。pH的RMSEP为0.18,R2为0.72。泥炭湿度的RMSEP为1.95%,R2为0.62。如果泥炭剖面的有壳变形虫种类组成与本研究的训练样本集相同,水位埋深、pH和泥炭湿度可以分别以±7.39 cm、±0.18和±1.95%的平均误差进行重建。 展开更多
关键词 rioja软件包 转换函数 有壳变形虫(Testate amoebae) 水位埋深 pH 泥炭湿度
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Reassessment of Prejanopterus curvirostris, a Basal Pterodactyloid Pterosaur from the Early Cretaceous of Spain 被引量:1
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作者 Xabier PEREDA-SUBERBIOLA Fabien KNOLL +2 位作者 José Ignacio RUIZ-OMEACA Julio COMPANY Fidel TORCIDA FERNNDEZ-BALDOR 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1389-1401,共13页
Prejanopterus curvirostra, from the Early Cretaceous of La Rioja province, was the first pterosaur genus and species described from Spain. The material comprises disarticulated cranial and postcranial remains from sev... Prejanopterus curvirostra, from the Early Cretaceous of La Rioja province, was the first pterosaur genus and species described from Spain. The material comprises disarticulated cranial and postcranial remains from several individuals. The fossil-bearing bed is assigned to the lacustrine Leza Formation (eastern Cameros Basin, NW margin of the Iberian Range). This unit is regarded as either Berriasian-Valanginian or Barremian-Aptian. Prejanopterus curvirostris (specific name emended) was originally diagnosed on the basis of several characters of which the most significant was a lateral curvature of the rostrum. Re-examination of the holotype (rostrum) and paratype (partial rostrum with teeth) indicates that there is no genuine sideways bend of the preserved premaxilla-maxilla segments, but a slight dorsal curvature. Prejanopterus is characterized by a unique combination of characters: an emended diagnosis is provided. In contrast with previous estimates, the wing span of Prejanopterus was probably not much (if ever) in excess of 2 m. A phylogenetic analysis suggests that Prejanopterus is a basal pterodactyloid positioned between Pterodactylus and Cycnorhamphus- Gallodactylus. Prejanopterus represents the first evidence of Pterodactylidae in the Early Cretaceous of the Iberian Peninsula. 展开更多
关键词 PTEROSAURIA Prejanopterus Leza Formation Early Cretaceous La rioja Spain
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