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出 处:《植物保护学报》1998年第3期281-286,共6页Journal of Plant Protection
基 金:"八五"国家科技攻关项目;陕西省自然科学基金
摘 要:1992年4月~1995年4月作者在河南灵宝程村黄土塬农作区对棕色田鼠种群数量进行了逐月调查。结果表明,春季3、4月份种群数量高,夏季7、8月份数量低,而秋季10月份数量又高,然后又降低,呈典型的双峰型。在对棕色田鼠种群年龄结构、繁殖强度等研究的基础上,探讨了种群消长机理和种群调节因子。发现3个月前的成亚比、2个月前的繁殖强度、温度指数、降雨量指数分别和密度呈显著相关,用以上因子建立多元回归方程预测3个月后的种群动态趋势。该鼠4月份密度和10月份的密度显著相关,年龄结构与冬季降水量和翌年4月的密度显著相关,从而建立方程预测10月份密度和翌年4月的密度。经验证,预测值与实测值相吻合。The populations dynamics of mandarin vole were investigated every month from April 1992 to April 1995 in agriculture area on loess plateau in the west of Henan. According to statistical data, the seasonal fluctuation of mandarin vole exhibited a high-low-high annual pattern. The first peak occurred in spring (April), and the second in autumn (October). Further more based on the study on the population structure, the reproduction characteristics of mandarin vole from April 1992 to April 1995, reasons of seasonal variation were studied, regulation factors were found. Ratio of adults and sub-adults three months before, reproductive capability two months before , the temperature index and the rainfall index are correlative with population density. It showed that seasonal population fluctuation not only is the reflection of age structure and reproduction capability but also is restricted by external causes such as climate factors. Based on the study of several major factors that influence the population density, we made a linear regression equation with three factors to forecast the population density three months later. It is also found that the population density of April is correlative with that of October. The age structure and rainfall in winter is correlative with the density of April of next year. The forecast projects were made out to forecast the density of October and density of April of next year. The results of forecast by the projects were identical with concrete instance which showed that the forecast projects were reliable.
分 类 号:S443[农业科学—农业昆虫与害虫防治]
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