Aquatic insect diversity in a tropical Vietnamese stream in comparison with that in a temperate Korean stream

Abstract

A comparative investigation on aquatic insect diversity was conducted in a tropical stream in Southeast Asia (the Dak Pri stream in southern Vietnam; stream orders II-V, two sites per stream order) with a reference temperate stream in Northeast Asia (the Gapyeong stream in central Korea) in March 2001 and April 2000, respectively. The numbers of aquatic insect taxa in Dak Pri stream (268 species, mostly undescribed, 230 genera, 91 families, and 9 orders; 110.5 ± 17.1 species per site) were about twice those in Gapyeong stream (133 species, 98 genera, 51 families, and 8 orders; 60.3 ± 8.5 species per site). Coleoptera, Trichoptera, Ephemeroptera, and Diptera were the major aquatic insect orders with high taxonomic richness, and Coleoptera, Odonata, and Hemiptera contributed to the higher degree of aquatic insect diversity in Dak Pri stream. The species diversity indices of Dak Pri stream (4.37 ± 0.19) were higher than those of Gapyeong stream (3.73 ± 0.42), whereas the dominance indices of Dak Pri stream (0.195 ± 0.046) were lower than those of Gapyeong stream (0.346 ± 0.113). Collector-gatherers were predominant in both streams; shredders were more abundant in Dak Pri stream while scrapers were more abundant in Gapyeong stream. Factors affecting the higher degree of aquatic insect diversity in Dak Pri stream are discussed.

Aquatic insect faunas and communities of a mountain stream in Sapa Highland, northern Vietnam

“…Because of this, the aquatic insect faunas and community compositions of the stream evidenced a mixture of temperate and tropical features. The number of aquatic insect taxa found in the Sapa Highland (216 species, 139 genera, and 61 families) was larger than that of Tam Dao National Park in northern Vietnam (145 species, 127 genera, and 63 families) (Nguyen et al 2001) or Bach Ma National Park in central Vietnam (143 species, 119 genera, and 65 families) (Cao et al 2008), but was smaller than that of Dak Pri stream in southern Vietnam (268 species, 230 genera, and 91 families) (Hoang and Bae 2006). Although these comparisons were not predicated on the same sampling methods (i.e., spatial and temporal scales and duplicates), the taxa richness of the Sapa Highland was determined to be relatively larger than has generally been observed in northern Vietnamese streams (e.g., Tam Dao National Park) or Northeast Asian temperate streams (e.g., Gapyeong stream in Korea) (Hoang and Bae 2006).…”

“…The biodiversity of aquatic insects in a stream can be determined by a variety of ecological and environmental factors on local, basin, and regional scales, including habitat complexity and biogeographical history (Vinson and Hawkins 1998;Hoang and Bae 2006). Although the Muonghoa Stream in the Sapa Highland is located within mainland Southeast Asia, its general environment and aquatic insect fauna differ from those of typical tropical streams in Southeast Asia due to its geographical location.…”

“…In previous studies, Nguyen et al (2001) studied the altitudinal distribution of aquatic insects in a stream in Tam Dao National Park in northern Vietnam, and Cao et al (2008) conducted a faunistic study of aquatic insects in Bach Ma National Park in central Vietnam. Hoang and Bae (2006) demonstrated that a tropical stream in southern Vietnam evidenced a higher degree of aquatic insect diversity than that observed in temperate streams in Korea. The aquatic insect fauna and the community compositions of the Sapa Highland have not yet been investigated, with the exception of a few fragmented taxonomic studies of some aquatic insect groups (Nguyen and Bae 2004;Hoang and Bae 2005;Cao et al 2007).…”

Spatial Distribution of Benthic Macroinvertebrate Assemblages in Relation to Environmental Variables in Korean Nationwide Streams

“…However, temperate Korean streams were relatively rich in Ephemeroptera, Diptera, and Trichoptera when compared with tropical streams for the higher biodiversity of Gastropoda, Decapoda and other insect orders such as Odonata and Hemiptera [39,40] (Table 2). The taxonomic composition also included a large number of rhithronic fauna that prefer stony substrates.…”

Spatial and temporal variation of benthic macroinvertebrates in the Nam Gnom Basin receiving discharged waters from the Nam Theun 2 Reservoir (Lao PDR)

“…In 2009, the Mekong River Commission (MRC) estimated that the majority of the projects in the Lower Mekong Basin were located in Lao PDR (MRC, 2010). Interest in using macroinvertebrates to assess environmental changes is growing in the region such as in Vietnam (Hoang & Bae, 2006;Jung et al, 2008;Hoang et al, 2010) and in Thailand (Mustow, 2002;Getwongsa & Sangpradub, 2008;Thani & Phalaraksh, 2008;Boonsoong et al, 2008). However, in Lao PDR, knowledge and use of benthic macroinvertebrates for bioassessment studies remain scarce (Davidson et al, 2006;Pathoumthong & Vongsombath, 2007).…”