生态敏感地区的荒漠蝗虫防治:需要指导原则

进行大面积荒漠蝗虫的化学防治涉及各种景观区和生态系统,在环境敏感地区或其周边地区,农药喷撒没有严格的限制,作业者往往忽视这些地区的敏感性.人们对荒漠蝗虫控制所带来的环境问题的关注程度与日俱增,因而有必要制定明确的指导性防治原则.本文旨在确定和描绘非洲东北部对杀虫剂污染特别敏感的区域,如保护区、湿地、人口居住区、绿洲,以及候鸟集中分布的地区,这些区域与1986～1998年间实际进行的荒漠蝗虫防治区域相对比.结果表明,环境脆弱地区,特别是湿地,如临时性水域和红树林,以及人类居住区附近都进行过化学防治,而且一定程度上还涉及到保护区和候鸟大量聚集区.     

Predatory spider mimics acquire colony-specific cuticular hydrocarbons from their ant model prey

The integrity of social insect colonies is maintained by members recognising and responding to the chemical cues present on the cuticle of any intruder. Nevertheless, myrmecophiles use chemical mimicry to gain access to these nests, and their mimetic signals may be acquired through biosynthesis or through contact with the hosts or their nest material. The cuticular hydrocarbon profile of the myrmecophilous salticid spider Cosmophasis bitaeniata closely resembles that of its host ant Oecophylla smaragdina. Here, we show that the chemical resemblance of the spider does not arise through physical contact with the adult ants, but instead the spider acquires the cuticular hydrocarbons by eating the ant larvae. More significantly, we show that the variation in the cuticular hydrocarbon profiles of the spider depends upon the colony of origin of the ant larvae prey, rather than the parentage of the spider.