Zooplankton Distribution in Tropical Reservoirs, South China

Abstract

The zooplankton of 18 reservoirs of South China was investigated in 2000. 61 Rotifera species, 23 Cladoceras and 14 Copepodas were identified. The most frequent Rotifera genera were Keratella, Brachionus, Trichocerca, Diurella, Ascomorpha, Polyarthra, Ploesoma, Asplanchna, Pompholyx and Conochilus. Bosmina longirostris, Bosminopsis deitersi, Diaphanosoma birgei, D. brachyurum and Moina micrura were typical of Cladocera in the reservoirs. Phyllodiaptomus tunguidus, Neodiaptomus schmackeri and Mesocyclops leuckarti were the most frequent Copepoda and M. leuckarti dominated Copepoda in most reservoirs. High zooplankton species richness with low abundance was characteristic of the throughflowing reservoir, whereas low species richness with low abundance was found in the reservoir with the longest retention time. Relative high abundance and medium species diversity were the distinction of intermediate retention time reservoirs. IntroductionReservoirs, as man-made lakes, occupy an intermediate position between rivers and natural lakes by combining numerous features of rivers and lakes (KIMMEL et al., 1990). Natural lakes are rich in zooplankton, however, if a zooplankton population survives in a river or stream, it must reproduce at a rate equal to or greater than its displacement downstream by the current (MARZOLF, 1990). When rivers are dammed, the flow is temporarily halted in the impoundment and new lentic habitats are established. Zooplankton rapidly colonize these habits and can reproduce at a rate high enough to maintain the populations. However, reservoirs often undergo rapid and extensive fluctuations in flow velocities and water levels. The retention time of water in reservoirs is variable and is likely to influence the fate of zooplankton (MARZOLF, 1990). Reservoirs are sufficiently distinct in their basic characteristics to offer novel ways of investigating the adaptations of aquatic organisms.Unlikely in the North Temperate Zone where zooplankton have been studied intensively over a long time, species composition in tropical zooplankton is far less investigated. Moreover, most of the knowledge comes from detailed studies concentrating on relatively few sites (Lakes Chad, George, Lanao, Valencia, Gatun, Castanho and several other African, South American, Australian and South East Asian lakes and reservoirs) as referred by NILSSEN (1984), HAWKINS (1988), DUNCAN (1984), b), ARCIFA (1984 and ARCIFA et al. (1992). In South China (Guangdong Province), where natural lakes are scarce (only 13 km 2 ), a great amount of reservoirs were constructed during 1950 -1980. This contribution aims to investigate characteristics of zooplankton distribution in the reservoirs of Internat. Rev. Hydrobiol. 88 2003 6 602-613

Seasonal variability of water quality and metazooplankton community structure in Xiaowan Reservoir of the upper Mekong River

“…This could be explained by the combined effects of zooplankton physiological limitations and the low phytoplankton growth in winter. Compared with other eutrophic reservoirs in China (Lin et al, 2003), the Chl-a contents in the Xiaowan Reservoir during winter were still low (<1 µg L -1 ). Several authors reported that the rotifer were richest in the number of individuals in reservoir (Nogueira, 2001;Seda and Devetter, 2000).…”

Türkiye İçsuları için Yeni Bir Rotifer Türü

“…P. truncatum is reported as thermophilic specimen (Koste 1978), and its embryonic development occurs at high temperatures, and this period continues for a long time (Edmondson 1960). P. truncatum was reported from various areas in the world including; Russia (Telesh 1995), Canada (Swadling et al 2000), China (Lin et al 2003;Zhaou et al 2009 Kehayias et al 2008), and North America (Barbiero and Warren 2011), except Turkey which is located in Palearctic region. Also, it has been a subject of several studies (e.g.…”

Reservoirs of Guangdong Province, South China: An Increasing Threat of Eutrophication

“…After these large-scale water blooms, the local government began to realize the seriousness of water pollution, and many significant decisions were made with an aim at water resources protection. Another two surveys of harmful Cyanobacteria and internal loading in the reservoir were completed in 2003-2004and 2007-2008(Han et al 2006, Han 2010.…”

“…In total, a minimum of 61 species of Rotifera, at least 23 species of Cladocera and 18 species of Copepoda have been identified in samples collected in summer and winter (Lin et al 2003). The majority of rotifer species are monogononts, and bdelloids are represented only by Rotaria spp.…”