基于鱼类生长特征和营养成分视角分析豹纹鳃棘鲈增殖放流水域的适宜性

Suitability analysis of stocking waters of Plectropomus leopardus based on fish growth characteristics and nutrient composition

摘要:

目的 开发一种评估鱼类增殖放流水域适宜性的方法。方法 通过放流小批量的豹纹鳃棘鲈到自然水域中，基于回捕群体和养殖群体的生长特征及肌肉营养成分分析，来反推、评估增殖放流水域的生境适宜性。结果 豹纹鳃棘鲈的回捕群体与养殖群体均呈等速生长，回捕群体的生长条件因子a值大于养殖群体，肥满度亦大于养殖群体；二者肌肉中水分、粗灰分、粗蛋白、粗脂肪、必需氨基酸含量和氨基酸总量差异不显著。豹纹鳃棘鲈回捕群体的肌肉中单不饱和脂肪酸、C20:4n6、C20:5n3、C22:6n3含量显著高于养殖群体。豹纹鳃棘鲈回捕与养殖群体的肌肉中除锰和硒外，其他元素含量均差异不显著。豹纹鳃棘鲈回捕群体的肌肉中铅含量显著低于养殖群体，其他重金属差异不显著。结论 放流海域的生境条件能保证各项营养物质的均衡和积累，满足豹纹鳃棘鲈生长发育的需求。本实验验证了基于生长特征和营养成分视角分析增殖放流水域适宜性的可行性，并形成了该方法的流程图，为今后评估鱼类增殖放流水域的适宜性提供了一种新思路，亦可引申至其他水生生物种类。

Abstract:

Global marine fishery resources are declining due to the effects of overfishing, climate change, and environmental pollution. Stock enhancement is considered to be an effective means of increasing the number of biological populations and promoting the sustainable development of fisheries. However, the effectiveness of stock enhancement is affected by many factors. Among them, the habitat conditions at the releasing waters directly affect the released fish's survival rate and growth rate. Therefore, before the fish were released in large numbers, it is important to evaluate the suitability of this water area. At present, the research on evaluating the suitability of the release waters is mainly to carry out the background investigation of the proposed releasing waters by sampling before releasing, including water quality, food organisms, fishery resources and other aspects. However, this investigation method was expensive. A small batch of Plectropomus leopardus was first released into the waters and then recaptured them in this study to develop a method for evaluating the suitability of fish-releasing waters. The growth characteristics and muscle nutrients of the recaptured P. leopardus and the farmed P. leopardus were compared to evaluate whether the waters were suitable for the growth of released fish. The results showed that the allometric growth factor b value of the recaptured and farmed populations of P. leopardus was close to 3, showing an isokinetic growth state. The growth condition factor a value of recaptured P. leopardus was more significant than that of farmed P. leopardus. The condition factor K value was also greater than that of farmed P. leopardus. There were no significant difference in moisture, crude ash, crude protein, crude fat, essential amino acid content, and total amino acid content in the recaptured and farmed P. leopardus muscles. The contents of monounsaturated fatty acids, C20:4n6, C20:5n3 and C22:6n3, in muscle of recaptured P. leopardus were significantly higher than those in farmed P. leopardus. There were no significant differences in other elements except manganese and selenium in the recaptured and farmed P. leopardus muscles. The lead content in the muscle of recaptured P. leopardus was significantly lower than that of farmed P. leopardus, and there were no significant differences in other heavy metals. In short, this study indicated that the habitat conditions of the releasing waters could ensure the balance and accumulation of various nutrients to meet the growth and development needs of P. leopardus. This study verified the feasibility of evaluating the suitability of fish-releasing waters based on the fish growth characteristics and nutrient composition and formed the evaluation process. It can provide new insight for evaluating the suitability of fish-releasing waters in the future and can also be used for other aquatic species.