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作 者:刘忠义[1] 干友民[1] 陈燕[1] 高德武[1] 周卫生[1]
机构地区:[1]四川农业大学草业科学系,四川雅安625014
出 处:《安徽农业科学》2006年第17期4333-4334,共2页Journal of Anhui Agricultural Sciences
摘 要:通过2001年1~12月的观测、分析表明,四川省雅安市草坪在全年共有3次明显的杂草发生高峰,杂草的发生高峰期分别集中在早春(3月中下旬)、春末夏初(5月上~下旬)、秋末冬初(11月初~下旬).3次杂草发生高峰期,都与日均温和日照时数密切相关。在3个高峰期,第1限制因子不同,早春高峰期气温为第1限制因子;春末夏初高峰期杂草的发生与温度、降水、日照的同步呈正相关;秋末冬初高峰期的第1限制因子为日照。盛夏降水过多反而在一定程度上抑制杂草的发生。By the analysis of some statistics from January to December 2001, it showed that there were three periods when the weed grew apparently faster,The three periods were in early spring, later spring and early summer, later autumn and early winter, The three periods when the weed grew appar-ently faster were closely related with the average temperature and the hours of sunshine, The most important factor which influenced the three periods were variable and in the early spring it was the temperature; in later spring and the early summer, it was temperature, rainfall and sunshine and in later autumn and early winter,it was only sunshine. In addition, too much rainfall in mid-sumner limited the growth of weed.
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