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四种谷类作物次生节根群空间分布特点 被引量:4
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作者 杨珍平 苗果园 《山西农业大学学报(自然科学版)》 CAS 2010年第2期137-142,共6页
为丰富根系研究领域,补充小杂粮作物根系研究空白,试验采用普通盆栽、网隔盆栽与田间土钻取根相结合的方法,研究了相对相同条件下,玉米、高粱、谷子和黍子4种谷类作物次生节根群空间分布特点。结果表明,4种谷类作物次生节根的空间分布... 为丰富根系研究领域,补充小杂粮作物根系研究空白,试验采用普通盆栽、网隔盆栽与田间土钻取根相结合的方法,研究了相对相同条件下,玉米、高粱、谷子和黍子4种谷类作物次生节根群空间分布特点。结果表明,4种谷类作物次生节根的空间分布较类似:①以根轴为圆心,4种作物从根轴向各个方位伸展的次生节根长度近似相等,均在20 cm左右;向各个方位伸展的根数亦近似相等;次生节根与种子根的夹角普遍扩大。②根轴根重垂直分布与行间根重垂直分布均符合Y=A.e-BX的锥形负指数递减模型;③将4种作物根群特点作聚类分析表明,在2.0954的距离上,玉米和高粱根系特点相近;在3.9383的距离上,谷子和黍子根系特点也相近;在5.57的距离上,4种谷类作物根系特点皆相近。 展开更多
关键词 谷类作物 次生节根群 空间分布
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大型构造节理及其遥感调查方法
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作者 李光伟 《铁道工程学报》 EI 1993年第1期39-43,共5页
一、大型构造节理的概念和发育特征传统的节理概念是指地壳中分布最广的切割岩石的一种小型地质构造。分原生节理和次生节理两大类。原生节理是指沉积成岩过程中因失水收缩而生成的节理,或是熔岩,岩浆成岩过程中因冷凝而生成的节理,次... 一、大型构造节理的概念和发育特征传统的节理概念是指地壳中分布最广的切割岩石的一种小型地质构造。分原生节理和次生节理两大类。原生节理是指沉积成岩过程中因失水收缩而生成的节理,或是熔岩,岩浆成岩过程中因冷凝而生成的节理,次生节理是在岩石成岩之后形成的节理。 展开更多
关键词 构造 遥感调查 成岩过程 小型地质构造 次生节 理组 区域构造应力场 发育规模 碳酸盐岩分布 延伸方向
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Dominance hierarchy and social relationships in a group of Captive black-and-white snub-nosed monkeys (Rhinopithecus bietl) 被引量:2
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作者 Liang-Wei CUI Qing-Lei SUN Bao-Guo LI 《Zoological Research》 CAS CSCD 北大核心 2014年第3期204-213,共10页
Different types of dominance hierarchies reflect different social relationships in primates. In this study, we clarified the hierarchy and social relationships in a one-male unit of captive Rhinopithecus bieti observe... Different types of dominance hierarchies reflect different social relationships in primates. In this study, we clarified the hierarchy and social relationships in a one-male unit of captive Rhinopithecus bieti observed between August 1998 and March 1999. Mean frequency of agonistic behaviour among adult females was 0.13 interactions per hour. Adult females exhibited a linear hierarchy with a reversal of 10.9%, indicating an unstable relationship; therefore, R. bieti appears to be a relaxed/tolerant species. The lack of a relationship between the agonistic ratio of the adult male towards adult females and their ranks indicated that males did not show increased aggression towards low-ranking females. Differentiated female affiliative relationships were loosely formed in terms of the male, and to some extent influenced by female estrus, implying that relationships between the male and females is influenced by estrus and not rank alone. A positive correlation between the agonistic ratio of adult females and their ranks showed that the degree to which one female negatively impacted others decreased with reduction in rank. Similarly, a positive correlation between the agonistic ratio of females and differences in rank suggests that a female had fewer negative effects on closely ranked individuals than distantly ranked ones. These data indicate that rank may influence relationships between females. A steeper slope of regression between the agonistic ratio and inter-female rank differences indicated that the extent of the power difference in high-ranking females exerting negative effects on low-ranking ones was larger during the mating season than the birth season, suggesting that rank may influence the mating success of females. 展开更多
关键词 Dominance style Hierarchy LINEARITY Rhinopithecus bieti Social relationship
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