nasonovia ribisnigri (mosely) is one of the most important pests of the lettuce plant and it was reported for the first time in ahvaz in 2008. in order to investigate the dominant species of its natural enemies and their population fluctuations, sample were taken arbitrarily from fifty plants twice a week during the growing season in 2010-2012. in this study, ten species of predators, three spe...

many factors, particularly the planted cultivar for oil production and climatic conditions, can affect olive oil quality. this research was conducted with 12 olive cultivars in olive research stations with different climatic conditions (taroum, roodbar, gorgan, kazeron and sarpolezehab). fruits with 4-4.5 ripening indices were harvested in each region. fatty acids composition data were analyzed...

Models are developed in which prey preferences vary between individual predators but the preference of an individual does not change with prey relative density. These two properties generally lead to the surprising conclusion that the aggregate preference of a population of predators does change with prey relative density. This phenomenon may result in negative or positive switching, depending ...

Many democratic governments recognize a duty to conserve environmental resources, including wild animals, as a public trust for current and future citizens. These public trust principles have informed two centuries of U.S.A. Supreme Court decisions and environmental laws worldwide. Nevertheless numerous populations of large-bodied, mammalian carnivores (predators) were eradicated in the 20th ce...