fish species composition

基本解釋

After 20 century 70s, fish species composition significant changed on the basis of the species composition of fish-scale-deposition.
通過魚鱗種類組成比例的改變，發(fā)現(xiàn)上世紀(jì)70年代后，魚類資源結(jié)構(gòu)發(fā)生了顯著的變化。
Fish species composition in seven Lakes of the Yunnan Plateau from 1990s to 2004 were compared to investigate variation and reasons for endangered native fishes.
根據(jù)七個(gè)云南高原湖泊近年漁獲物的變化情況，探討了云南土著魚類的變化特征和瀕危的原因。
According to the data selected from bottom trawl fishery resource monitoring in the East China Sea from 1997 to 2000, the species composition and seasonal variation of small-sized fish were analysed.
根據(jù)1997~2000年東海區(qū)底拖網(wǎng)漁業(yè)資源調(diào)查資料，分析和討論了東海區(qū)小型魚類的種類組成和季節(jié)變化。