海表温度时空分布模式对西北太平洋柔鱼生物学特征的影响

Effects of sea surface temperature distribution patterns on the biological characteristics of neon flying squid (Ommastrephes bartramii) in the Northwest Pacific

摘要:

目的 旨在提出基于深度学习方法挖掘海表时空分布模式，并分析对不同月份雌、雄柔鱼生长发育变化的影响。方法 实验基于2016年7—10月西北太平洋柔鱼的生物学测定数据，分析其胴长、体重和性腺成熟度的组成，并采用幂指数方程分月拟合雌、雄柔鱼胴长和体重的关系；采用深度卷积嵌入式聚类 (DCEC)模型，基于MODIS-Aqua 和 MODIS-Terra 海表面温度三级反演图像数据提取海表温度 (sea surface temperature, SST)的分布模式，用于反映各月调查站点对应的SST时空分布特征与规律；在此基础上，分析不同月份SST时空分布模式对雌、雄柔鱼生长发育的影响。结果 ① 2016年7—10月，西北太平洋雌、雄柔鱼的生长与发育不完全同步，雌性生长速率较快，雄性性腺发育速率较快。②基于DCEC模型提取得到了4类SST图像特征，能够较好地反映各月调查站点对应的SST时空分布模式，体现了厄尔尼诺现象、黑潮和亲潮等对海表温度的影响。③ 7—8月，柔鱼平均体重、胴长和性腺成熟度偏低，雌、雄个体差别不大，与SST时空分布模式的关系不显著。④ 9—10月，在SST变化较均匀但整体温度较低时，柔鱼平均体重、胴长和性腺成熟度均偏低；在SST变化较均匀但整体温度升高时，柔鱼的平均体重、胴长和性成熟个体数量明显上升，雌鱼生长速率较雄鱼快，但雄性成熟速率较雌性更快；冷暖水相遇形成比较明显的界限时，雌、雄柔鱼的胴长和体重达到最大值，但性腺发育有所延缓。结论 本研究基于深度学习DCEC模型挖掘了SST时空分布模式对不同月份雌、雄柔鱼生长发育变化的影响，为进一步了解西北太平洋柔鱼生物学特征提供参考。

Abstract:

The neon flying squid (Ommastrephes bartrami) is an economically important cephalopod with a short life cycle, and its biological characteristics are highly susceptible to changes in sea surface temperature (SST). This study aims to investigate the influence of SST distribution patterns in the Northwest Pacific on the growth and development of neon flying squid, using deep learning methods to analyze termporal and spatial variations. Data on mantle length, body weight and gonad maturity of O. bartrami from July to October 2016 were analyzed, and the relationship between mantle length and body weight was modeled using a power index equation. The Deep Convolutional Embedded Clustering (DCEC) model was employed to extract SST distribution patterns from MODIS-Aqua and MODIS-Terra three-level inversion image data. The results showed that: ① During July to October 2016, the growth and development of female and male O. bartrami in the Northwest Pacific were not completely synchronized; females exhibited a faster growth rate, while males had a faster gonad development rate. ② Four types of SST image features extracted using DCEC model reflected the monthly SST characteristics of survey sites, corresponding to the effects of El Niño, Kuroshio Current, and Oyashio Current. ③ From July to August, squid exhibited low average body weight, mantle length, and gonad maturity, with minimal differences between sexes and no significant relationship with SST distribution pattern. ④ From September to October, when SST changed uniformly but overall temperatures were low, squid had low average weight, mental length, and gonad maturity. However, when SST changed uniformly with an overall temperature, average body weight, mantle length, and the number of sexually mature individuals significantly increased. Females grew faster than males, but male maturity rates exceeded those of females. When cold and warm waters met, forming a clear boundary, squid mantle length and weight reached their maximum, but gonad development was delayed. This study, based on the deep learning DCEC model, provides insights into the effects of SST distribution patterns on the growth and development of neon flying squid and offers a reference for further understanding the biological characteristics of O. bartrami in the Northwest Pacific.