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81.
82.
The numbers of alien species in freshwater systems and their detrimental impacts on the stability of ecosystems and global
species diversity are increasing. To predict and assess such impacts, a thorough knowledge of the autecology and life cycle
of the alien species is required. Limnomysis benedeni is common and one of the most invasive mysids in Europe. Here we show a clear dependency of the development time of the brood
of L. benedeni on water temperature. In laboratory experiments (one in spring 2008 and two in 2009, in spring and summer) under controlled
conditions, we determined embryonic development times and the probability of survival of the females and juveniles at water
temperatures ranging from 4 to 25°C. At 6.5 and 25°C, the probability of survival of both the females and the larvae was lower
than at 10, 15, or 20°C. Since the development time is one of the key characteristics of the life cycle and is therefore necessary
to calculate, for example, birth and mortality rates, we determined an equation for the development time as a function of
the water temperature. This information will be useful to understand the distribution potential of this invasive species. 相似文献
83.
Grazing and nutrient influences of Daphnia and Eudiaptomus on phytoplankton in laboratory microcosms
In two experiments, top-down and bottom-up influences of theherbivorous crustaceans Daphnia pulicaria and Eudiaptomus grac$$$loideson phytoplankton were compared in laboratory microcosms. Ina long-term experiment (63 days), both grazers were able toestablish populations. The Daphnia population exerted strongergrazing pressure, whereas Eudiaptomus fed more selectively.Daphnia retained relatively more phosphorus (P) and thus causedalgal P limitation; with Eudiaptomus as a grazer, both nitrogen(N) and P remained limiting. In a short-term experiment (1 day),N and P release rates and algal-specific grazing rates by bothconsumers were measured. In this experiment, the increase inconcentrations of soluble mineral nutrients ( 相似文献
84.
85.
The whitefly species of the genus Aleurolobus Quaintance and Baker are reviewed from Taiwan. A total of nine species are included. Aleurolobus shiiae Takahashi is new to Taiwan. Aleurolobus osmanthi Young is considered as a junior synonym of Aleurolobus taonabae (Kuwana). A new species, Aleurolobus rubus Dubey and Ko, is described, and the puparia of the new species are diagnosed in a combination of characters: the dorsal pores scattered over dorsum; each located on a large subcircular, chitinised cuticular dorsal marking; faint eye spots; broader submargin; and the vasiform orifice set anterior to the caudal end of puparium by nearly twice of its own length. The record of Aleurolobus philippinensis Quaintance and Baker, and Aleurolobus setigerus Quaintance and Baker from Taiwan is discussed. The puparial diagnosis of each species, identification key to species so far known from Taiwan and illustrations for each species are provided. 相似文献
86.