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马尾松舞毒蛾卵块的空间分布型,用聚集度指标度量适合聚集分布。Iwao的回归分析法与Taylor幂法则也是确定聚集型分布的好方法,结果都说明是聚集型的。由此可确定抽样调查的最适抽样数,编制序贯抽样分析表,用于预测预报和防治效果的检验。 相似文献
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Forecasting the spatial dynamics of gypsy moth outbreaks using cellular transition models 总被引:5,自引:0,他引:5
A series of cellular transition probability models that predict the spatial dynamics of gypsy moth (Lymantria dispar L.) defoliation were developed. The models consisted of four classes: Simple Markov chains, Rook's and Queen's move neighborhood models, and distance weighted neighborhood models. Historical maps of gypsy moth defoliation across Massachusetts from 1961 to 1991 were digitized into a binary raster matrix and used to estimate transition probabilities. Results indicated that the distance weighted neighborhood model performed better then the other neighborhood models and the simple Markov chain. Incorporation of interpolated counts of overwintering egg mass counts taken throughout the state and incorporation of historical defoliation frequencies increased the performance of the transition models. 相似文献
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通过对全地区杨树害虫的多年调查的结果表明:害虫种类多,主要以毒蛾类、刺蛾类和天牛类等的为害重,本文针对杨树主要害虫的发生危害特点,提出了相应的防治措施。 相似文献
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[目的]明确南京市主要植被群系毒蛾科昆虫群落结构及其多样性,以更好地保护南京市森林生态及植树造林成果。[方法]研究了南京市主要植被群系植物种类及毒蛾科昆虫种类、种群密度、分布及发生规律,并进行了多样性分析。[结果]南京市5种主要植被群系共有毒蛾科昆虫15属32种,优势种为枫毒蛾、条毒蛾、绿点足毒蛾、鹅点足毒蛾、华竹毒蛾;昆虫本身的生物学特征、气候条件、生态环境是影响蛾类群落结构及动态的主要因素;毒蛾科昆虫种群动态有明显的时序变化,这种变化在很大程度上与季节性的温度变化有关。[结论]研究结果为有害生物的预测预报和防治提供了理论依据。 相似文献
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描述了海南澳毒蛾属Orvasca Walker一新种,即异色澳毒蛾O.heterocolor sp.nov..新种与近似种的主要区别在于后翅基半部浅灰色,端半部淡黄色;抱器瓣深分叉,背侧一壁宽大,长方形,腹侧一壁相当小,三角形;阳茎直,近端部凹陷;阳茎端膜膨大,密被微刺.提供了成虫和雄性生殖器图片. 相似文献
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