Lethal Effect of Ammonia to Juvenile Metapenaeus Ensis

Abstract

By selecting different categories of ecological data in statistical analysis,a total of 20 empirical models were constructed for DO prediction withinearthern ponds,for indefinite period of time.The more variables involved,thehigher the power of interpretation of the model.A general survey of allmodels showed that DO at any time t deeply depended on a dummy variableZ,and the DO level at a previous time.Light intensity was the most consistantand significant environmental factor controlling DO fluctuation.Others factorsincluded pH,water temperature,carrying capacity,paddlewheel,windaction,and Secchi disk visibility.Effects of salinity,light extinction coefficient andwater depth were not significant.利用各種生態因子觀測資料從事統計分析之結果，建立了一共20個實證式模型，可供預測魚池中溶氧量變化之用。以自變數實際資料測試結果，顯示各模型的預測能力頗佳，並且隨著變數數量之增加而改善。對所有模型之整體性觀察顯示影響溶氧量變化最重要之因子爲前一段時間之溶氧量及一與時間有關之虚擬變數(z)。環境因子之影響則以光照强度最爲重要，其它因子順次爲pH，水溫，生物（草蝦）負荷量，水車數，風速及透明度。經鑑定爲影響不顯著之因子包括了鹽度，光衰減係數及水深三項。