吳鳳酉 碩士論文中英摘要
草蝦之成長及存活與棲所空間結構之關係
草蝦為一重要之水產養殖生物。近年來由於養殖業興盛，陸上養殖土地有限，加上草蝦之需求量不斷增加，各地大量養殖仍供不應求，因此高密度養殖
(intensive culture)逐漸成為目前之養殖趨勢。
本研究在 FRP水槽內放入水平及垂直空間結構，觀察草蝦與空間結構之關係。實驗包括三部份:
第一部份為草蝦在空間結構上之分佈。實驗結果顯示: 草蝦在水平空間結構上之分佈隨時間而改變，早上及中午之分佈傾向底層 (P<0.01)，傍晚及夜間之分佈亦顯著(P<0.01)，但不似早上及中午由下而上遞減；在網片上之分佈，中午及傍晚傾向選擇邊緣(P<0.01)；不同時間對水平空間結構之利用率沒有差異(P>0.05)。草蝦在垂直空間結構上之分佈，早上及中午在不同網片上分佈較均勻，傍晚之分佈則有差異
(P<0.01)，夜間較傾向兩側網片(P< 0.05)；在網片上之分佈，早上、傍晚及夜間傾向底層及邊緣(P< 0.01)；不同時間對垂直空間結構之利用率亦無差異(P>0.05)。第二部份為高密度養殖草蝦在不同空間結構處理下之成長與存活。實驗進行十二週。第九週後處理組平均體重已明顯大於對照組(不放任何空間結構)(P<0.05)，第十二週時差異更顯著
(P<0.01)；在生物量(Biomass)上，第九週時處理組已明顯大於對照組(p<0.05)，至第十二週時處理組之生物量幾乎為對照組的兩倍(p<0.01)，兩處理間無差異(p>
0.05 )；存活率以處理二(垂直空間結構)最好，第十二週時仍有 87﹪，與對照組(68﹪)有顯著差異(p< 0.05)。第三部份則從脫殼觀點來探討適當之放養密度。草蝦密度從
30尾/㎡ 至 55尾/㎡，處理組與對照組間之脫殼頻率都沒有差異 (p>0.05)；草蝦密度 55尾/㎡時，對照組的死亡率明顯大於垂直空間結構處理組
(p<0.05)。
The relation between
the growth and survival of Penaeus monodon and artificial shelter
Three experiments
were conducted in FRP tanks with artificial shelters to study
the effect of shelters on Penaeus monodon. In one experiment,
distribution of P. monodon on artificial shelters was examined.
Distribution of P. monodon in horizontal shelter changed with
time of day. It tends to stay on the bottom in the morning and
at noon but spreaded to the other layers in evening and at night.
P. monodon tends to distribute on edges at noon and in the evening.
The useage were not different in different time. Distribution
of P. monodon uniformly distribute among the vertical layers in
the morning and at noon. In the evening, however, P. monodon distributed
differently among the vertical layers. Except for time noon, P.
monodon tends to the edge and bottom in a vertical layer.
In the second
experiment, growth and survival of P. monodon kept in high density
and in tank with horizontal or vertical shelters was monitored.
It was fed with arti- ficial diet for twelve weeks. The biomass
and growth rate of P. monodon cultured under this experimental
condition were higher than the control(i.e., P. monodon cultured
in tank without artificial shelter). Survival rate of P. monodon
in tank with verticial shelters was the best.
In the third
experiment, molting frequenciesof P. monodon in tanks with or
without artificial shelters and in five density i.e., 30, 35,
40, 45 and 55 shrimp/㎡ were not significiantly different. But
the survival rate of P. monodon in vertical shelters and highest
density (i.e., 55 shrimp/㎡) was higher than the control.
|