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昆明翠湖公园三角枫材小蠹危害调查及防治对策 被引量:7
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作者 张威 李巧 +3 位作者 赵祎 刘波 郭宏伟 卢志兴 《云南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第2期294-298,共5页
2010年4月,对翠湖公园的主要行道树三角枫(Acer buergerianum Miq.)上材小蠹虫孔分布及材小蠹危害率进行了调查,提出了三角枫蠹害木蠹害等级分级标准,并计算了蠹害指数。结果表明:(1)三角枫蠹害木主干上的虫孔数随主干距地面高度的增加... 2010年4月,对翠湖公园的主要行道树三角枫(Acer buergerianum Miq.)上材小蠹虫孔分布及材小蠹危害率进行了调查,提出了三角枫蠹害木蠹害等级分级标准,并计算了蠹害指数。结果表明:(1)三角枫蠹害木主干上的虫孔数随主干距地面高度的增加而增加,距地面101~150 cm和151~200 cm处主干可作为三角枫蠹害状况调查的最适区段;(2)园内材小蠹危害率高达89.5%,受害三角枫的平均虫孔数为13.1/株;(3)园内三角枫轻度、中度和重度蠹害木的比例分别为42.9%,41.4%和5.2%,蠹害指数为47.1,三角枫正遭受普遍且严重的蠹害威胁。提出了加强虫情监测、开展物理防治和化学防治的防治对策及措施。 展开更多
关键词 三角枫材小蠹 虫孔密度 危害率 蠹害指数 情监测
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Seasonal Differences in Live Foraminiferal Densities: Case Studies from Tropical and Temperate Intertidal Environments
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作者 Ashleigh Costelloe Brent Wilson 《Journal of Environmental Science and Engineering(B)》 2015年第11期591-606,共16页
Statistically significant differences (when p 〈 0.05 using the permutation t-test) among Live Foraminiferal Densities (LFDs) recovered in August, November, March and May were detected at tropical Caroni swamp, Cl... Statistically significant differences (when p 〈 0.05 using the permutation t-test) among Live Foraminiferal Densities (LFDs) recovered in August, November, March and May were detected at tropical Caroni swamp, Claxton bay (Trinidad), temperate Cowpen marsh and Brancaster marsh (U.K.). The monthly mean LFDs of the foraminiferal metacommunities (all stations), assemblages (groups of stations defined by cluster analysis), and the agglutinated and calcareous specimens within each were compared separately. The LFDs of the Caroni swamp metacommunity did not fluctuate significantly among months, but significantly higher abundances of agglutinated specimens occurred in the upper assemblage in March; and calcareous specimens in the lower assemblage in November. At Claxton bay, monthly LFDs of the metacommunities and assemblages did not vary significantly, but calcareous and agglutinated species within each favoured dry (March and May) and wet (August and November) months respectively At the temperate marshes, significantly higher LFDs of the metacommunities and assemblages were recorded in warmer months. August blooms of the Cowpen marsh metacommunity was attributed to agglutinated specimens in the upper assemblage, and calcareous specimens in the lower assemblage. May blooms of the Brancaster marsh upper assemblage were attributed to calcareous specimens, but there were no seasonal blooms of the lower assemblage. 展开更多
关键词 FORAMINIFERA MARSH SWAMP INTERTIDAL SEASONAL trends densities.
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