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美洲斑潜蝇自然分布格局的研究
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作者 苏丽 仵均祥 周平伟 《西北农业学报》 CAS CSCD 2002年第4期9-12,共4页
逐行逐株调查了400余株自然生长棉花上美洲斑潜蝇危害的棉花叶片和幼虫潜道,在此基础上研究了美洲斑潜蝇的自然分布格局,结果表明:美州斑潜蝇在棉田发生的初期,其分布格局为均匀分布;在棉田发生一段时间后,即棉花生长进入蕾、花、铃盛期... 逐行逐株调查了400余株自然生长棉花上美洲斑潜蝇危害的棉花叶片和幼虫潜道,在此基础上研究了美洲斑潜蝇的自然分布格局,结果表明:美州斑潜蝇在棉田发生的初期,其分布格局为均匀分布;在棉田发生一段时间后,即棉花生长进入蕾、花、铃盛期,被害叶片在棉田仍呈均匀分布,但幼虫潜道在棉株上、中部和以整株棉花为取样单位时为聚集分布,在棉株下部则为随机分布。进一步分析表明,幼虫潜道在棉株上、中部的聚集是由环境因素所引起的;以整株为取样单位时的聚集是由环境因素或美洲斑潜蝇自身活动习性所引起的。当以整株棉花为取样单位时,幼虫潜道的聚块面积为1株棉花。 展开更多
关键词 美洲斑潜蝇 自然分布格局 棉花 发生规律
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高山松自然地理分布、生长与生态适应性研究进展 被引量:1
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作者 杜燕 包维楷 《四川林业科技》 2022年第6期1-10,共10页
高山松(Pinus densata)是云南松(Pinus yunnanensis)和油松(Pinus tabuliformis)的天然同倍体杂交种,是我国西南山区的特有种,具有较高的生态和经济价值。基于系统查阅的相关文献和著作,对高山松自然地理分布格局、物种起源与演化机制... 高山松(Pinus densata)是云南松(Pinus yunnanensis)和油松(Pinus tabuliformis)的天然同倍体杂交种,是我国西南山区的特有种,具有较高的生态和经济价值。基于系统查阅的相关文献和著作,对高山松自然地理分布格局、物种起源与演化机制、个体生长规律及其环境影响机制进行了综述,阐明了当前需要关注的4点研究内容:(1)物种现有的分布区域和完整的地理分布格局;(2)物种具体的起源地、迁移路线和演化规律;(3)幼树(DBH≤6 cm)生物量估测模型;(4)各器官在不同发育阶段的权衡关系以及对不同生态因子的响应模式和生理学机理。通过对上述内容的深入研究,进一步明确高山松的生态适应策略。 展开更多
关键词 高山松 自然地理分布格局 起源与演化 生长规律 生态适应性
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Distribution of Invasive Plant Species in Relation to Environmental and Anthropogenic Factors in Five Nature Reserves in Northern China 被引量:5
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作者 张渊媛 冯金朝 +1 位作者 桑卫国 薛达元 《Journal of Resources and Ecology》 CSCD 2012年第3期278-283,共6页
The relationships between invasive plant species and environmental and anthropogenic factors were analyzed in five nature reserves in northern China. The distribution of invasive plants was analyzed using a Canonical ... The relationships between invasive plant species and environmental and anthropogenic factors were analyzed in five nature reserves in northern China. The distribution of invasive plants was analyzed using a Canonical Correspondence Analysis. Stepwise backward multiple regression was then done to identify the most important environmental and anthropogenic factors determining the richness and distribution of alien plants in the reserves. Total invasive plant richness varied was 25 species, 12 species, 13 species, five species and five species across the nature reserves. Invasive species richness decreased in response to environmental factors such as maximum temperature and minimum precipitation and increased in line with human activities, the total area of farmland and volume of freight. Tropical plant species declined from 31% to zero while the species originally from North America gradually increased. In respect of family composition of invasive species, most species belonged to the composites, whose proportion increased from 15%-40% from north to south across the five nature reserves while species from other families varied greatly along this gradient. Life-forms of invasive plant species varied between the reserves, but annual and perennial herbs were generally dominant. Pathways of such species were highly related to human activities and utilizations. 展开更多
关键词 invasive species nature reserve Canonical Correspondence Analysis (CCA) distribution pattern
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