インドネシア・リアウ州コトパンジャン貯水池の上流・下流域の魚類相の多様性と分布

Diversity and distribution of fish fauna of upstream and downstream areas at Koto Panjang Reservoir, Riau Province, Indonesia.

• Netti Aryani
• Indra Suharman
• Azrita Azrita
• Hafrijal Syandri
• Ainul Mardiah

抄録

:本研究では、インドネシアの河川・貯水池における捕獲漁業は、収入の増加と生活の多様化を通じてインドネシア経済に重要な役割を果たしている。本研究では、インドネシア・リアウ州のコトーパンジャン貯水池の上流域と下流域における魚類の多様性とその分布パターンを把握するために、様々な魚網を用いて 12 ヶ月間に渡って魚類のサンプルを採取した。得られたデータは、形態学的特徴に基づく標準的な分類学的キーを用いて解析した。この地域の魚類の多様性は、アルファ多様性指数が非常に高く（シャノン指数=2.10、シンプソンD=0.21）、偶数性が低い（偶数性H/S=0.19）ことが示された。KMサイト（上流）とBBサイト（下流）のfishは、それぞれ8家族と11家族であった。RBサイトおよびKKサイト（下流）では、それぞれ16ファミリーおよび15ファミリーからの魚であった。KM, BB, RB, KK の各サイトでは、Cyprinidae が優占しており、それぞれ 33.45%、50.95%、43.04%、39.35%を占めていた。外来種、特にナイルティラピアはそれぞれ 20.15%、14.11%、5.62%、5.34%であった。また、上流貯水池と下流貯水池の間には違いが見られ、調査期間中、上流貯水池では外来種がわずかに増加し（11.39％対34.66％）、在来種は減少した（88.61％対65.34％）。 コトパンジャン貯水池の魚類相の多様性と分布は、上流域と下流域で異なっていた。その結果、上流域では外来種が優占していることがわかった。

: The capture fishery sectors in the river and reservoir play an important role in the Indonesian economy through increased income and diversification of livelihoods. The present study was conducted to ascertain fish diversity and their distribution pattern in the upstream and downstream areas of Koto Panjang Reservoir, Riau Province-Indonesia. : Fish samples were collected for a period of 12 months using a variety of fish nets at four sites; Koto Mesjid (KM) and Batu Bersurat (BB), located in the upstream area of Koto Panjang Reservoir and Rantau Berangin (RB) and Kuok (KK), located in the downstream area of Koto Panjang Reservoir. Data obtained were analyzed using standard taxonomic keys based on morphometric characters. : A total of 44 species belonging 19 families and 33 genera were recorded in the study area. Alpha diversity indices showed that fish diversity in this area was quite high (Shannon's index = 2.10 and Simpson-D = 0.21) and evenness was low (evenness H/S =0.19). The fish in KM and BB sites (upstream) were from eight and 11 families, respectively. In RB and KK sites (downstream), fish were from 16 and 15 families, respectively. In KM, BB, RB and KK sites, the dominant family was Cyprinidae, comprising 33.45%, 50.95%, 43.04% and 39.35% of all fish caught at each site, respectively. Exotic species, especially Nile tilapia, were 20.15%, 14.11%, 5.62%, and 5.34%, respectively. Some differences were also noted between the upstream and downstream reservoirs, with a slight increase in exotic species in the upstream reservoir over the study period (from 11.39% vs. 34.66%), corresponding to decrease of native species (from 88.61% vs. 65.34%). : The diversity and distribution of fish fauna were varied in upstream and downstream areas of Koto Panjang Reservoir. The exotic species were found to be dominant in the upstream reservoir areas.

Copyright: © 2019 Aryani N et al.