枸杞岛周围底栖海藻分布的回声探测及其插值研究

Research on the benthic algae distribution around Gouqi Island using digital echo sounding system and interpolation

以枸杞岛天然海藻场近岸50 m范围内的底栖海藻为研究对象,利用BioSonics回声探测仪采集的回声样本,对未采样区域进行反距离加权插值预测,使用该方法探测评估底栖海藻资源量具有经济、高效的特点。枸杞岛地区的底栖海藻呈斑块状分布,插值预测可有效弥补回声采样难以覆盖全部研究区域的不足,并能由点及面地表现完整研究区域内底栖藻的资源状况;反距离加权插值法"在空间上越靠近就越相似"的预测特点与底栖海藻呈斑块状生长特点的契合性,适用于预测底栖海藻的空间分布情况;赋予反距离加权插值法合适的幂指数可准确高效地预测评估底栖海藻的生长分布情况,本研究中p=5为最佳幂指数。目前回声探测方法和插值预测方法在海藻资源评估领域的应用尚处于研究初期,本文探索了其在复杂的海洋环境中的应用特点,评估其应用效能。

In order to research the benthic algae within the coverage of offshore 50m wide of Gouqi Island, on the one hand we acquired echo samples around Gouqi Island by BioSoics DT-X. On the other hand, we predicted the benthic algae coverage by inverse distance weight （IDW） interpolation for non-sampled area. This method which combines echo sounding and interpolation is economic and high-efficient. The results of the study show that benthic algae around Gouqi Island are distributed patchily. Interpolation makes up for the shortcoming that echo sampling cannot cover to reveal the total resources in the entire research range. While, ＂Closer in Space, more Similar in Coverage Degree＂ is the specific character of IDW interpolation, this fits well with the patchily growing benthic algae to predict benthic algae resource. When given a perfect power exponent, the IDW interpolation can predict and assess the distribution of benthic algae effectively, in this research the most suitable power exponent is p = 5. Now, the applications of Echo Sounding and Interpolation in assessing benthic algae resource are at the very beginning, even more, most of them are conducted in calm lakes and rivers and only a few similar studies have been clone in the ocean environment. At the present stage, deeper research is much needed. This paper digs and develops the application characteristics while conducting Echo Sounding and Interpolation Method to assess the benthic algae resources in complicated ocean environment.