The relationship between the reduction of nonstructural carbohydrate induced by defoliator and the growth and mortality of trees

Large scale herbivorous insect outbreaks can cause death of regional forests, and the events are expected to be exacerbated with climate change. Mortality of forest and woodland plants would cause a series of serious consequences, such as decrease in vegetation production, shifts in ecosystem structure and function, and transformation of forest function from a net carbon sink into a net carbon source. There is thus a need to better understand the impact of insects on trees. Defoliation by insect pests mainly reduces photosynthesis (source decrease) and increases carbon consumption (sink increase), and hence causes reduction of nonstructural carbohydrate (NSC). When the reduction in NSC reaches to a certain level, trees would die of carbon starvation. External environment and internal compensatory mechanisms can also positively or negatively influence the process of tree death. At present, the research of carbon starvation is a hotspot because the increase of tree mortality globally with climate change, and carbon starvation is considered as one of the dominating physiological mechanisms for explaining tree death. In this study, we reviewed the definition of carbon starvation, and the relationships between the reduction of NSC induced by defoliation and the growth and death of trees, and the relationships among insect outbreaks, leaf loss and climate change. We also presented the potential directions of future studies on insect-caused defoliation and tree mortality.     

《昆虫知识》2010年第47卷第3期要目预告

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研究表明蝗虫走路不凭“感”觉靠“视觉”

一项新研究发现，蝗虫并不是靠“感觉”走路，而是依靠“视觉”精确定位自己的每一步，这表明人类可能低估了蝗虫的视觉导向系统。此前研究表明，昆虫大多靠触角等器官凭“感觉”行走或飞行，依靠视觉引导行走对于脑部较小的昆虫来说似乎过于高级。     

蚯蚓运动行为的观察与研究

蚯蚓运动行为的观察与研究安瑞永（河北教育学院生物学系０５００９１）黄薇（石家庄市第六中学０５００５１）蚯蚓在形态结构上有许多与土壤钻穴生活相适应的特征，其运动行为也很特殊。了解蚯蚓的运动行为，对环节动物的教学和实验有一定的指导作用。人民教育出版社新出...     

昆虫与寄主植物的适应性及协调进化

昆虫与寄主植物的适应性及协调进化钦俊德（中国科学院动物研究所北京１０００８０）昆虫和植物都是地球上起源很早的生物类群。从化石的证据来推断，它们至少在３亿多年前已生活在一起，在不同地域建立起密切关系的生物群落。它们中不同的种类为了自身的生存和发展，并根...     

动物的文化行为

动物的文化行为(cultural behaviour)是指通过非遗传的方法把信息从一个世代传给另一世代的行为。文化行为与进化过程不同,进化过程必须借助于自然选择才能发生,而文化行为是不遗传的。可见,动物适应其生存环境可以通过体质的进化(遗传进化),也可以通过学习特定的技能(不遗传)。学会的技能不能借助于遗传传递给后代,但却可以通过印记     

蜜蜂总科化石新种（昆虫纲：膜翅目）

本文记述了膜翅目熊蜂科、木蜂科和蜜蜂科3属3新种,其中熊蜂科熊蜂属1种:鲁熊蜂Bombus luianus sp. nov., 木蜂科木蜂属1种:硅藻木蜂Xylacopa diatoma sp. nov. 和蜜蜂科蜜蜂属1种:长胫蜜蜂Apis longitibia sp. nov.。所有模式标本均采自山东山旺中新统硅藻土页岩中,现保存在山东省博物馆。