Phytoplankton production, succession and community composition is limited by nutrients, temperature and spectral properties. Elemental ratios serve as indicators for predicting productivity of phytoplankton including diatom. Deep ocean water (DOW) as a marine natural resource is rich in inorganic nutrients. In the present study, as part of the OTEC program, an initial attempt was made to characterize quantitatively the elemental ratios in DOW and relate to growth of the diatom, Chaetoceros sp. In addition, the production of Chaetoceros sp. in DOW was compared with a conventional nutrient enrichment medium, generally used for phytoplankton growth. To assess the productive ability of DOW, factorial experiments with Chaetoceros sp. were carried out with (i) unaltered DOW [100% DOW], (ii) admixtures [50:50] of DOW and surface seawater (SSW) [50% DOW], (iii) plain SSW, (iv) SSW enriched with nutrients and (v) DOW enriched with nutrients. Results of admixtures of seawater starting from 0% SSW to 100% DOW revealed optimum Redfield ratios at 50% dilution. Results on growth of Chaetoceros sp. in 100% DOW showed a sudden blooming on the 2nd and 3rd day. Chlorophyll ‘a’ values of 70 mg m⁻³ were obtained with DOW and SSW enriched with f/2 medium. Similarly with 50% DOW same chlorophyll ‘a' concentrations was reached on the 4th 5th day and declined on the 6th day. Results of the present study demonstrate that 100% and 50% dilutions of DOW could be used for intensive culture of Chaetoceros sp. and that biomass production could be achieved within 3 days compared to incubations which use a conventional medium.

浮游植物的生产，演替和群落组成受到养分，温度和光谱特性的限制。元素比率可作为预测包括硅藻在内的浮游植物生产力的指标。作为海洋自然资源的深海水（DOW）富含无机养分。在本研究中，作为OTEC计划的一部分，我们进行了初步尝试，以定量表征DOW中的元素比并与硅藻Chaetoceros sp。的生长有关。另外，Chaetoceros sp。的生产。将DOW中的NP与通常用于浮游植物生长的常规营养富集培养基进行了比较。为了评估DOW的生产能力，Chaetoceros的析因实验sp。用（i）不变的DOW [100％DOW]，（ii）DOW和地表海水（SSW）[50％DOW]的混合物[50:50]，（iii）平原SSW，（iv）富含养分和（v）富含营养的DOW。从0％SSW到100％DOW的海水混合物的结果表明，稀释50％时的最佳Redfield比率。Chaetoceros sp。生长的结果。在100％的DOW中，第二天和第三天突然绽放。用富含f / 2培养基的DOW和SSW获得70 mg m ^-3的叶绿素“ a”值。类似地，DOW为50％时，第4天第5天达到相同的叶绿素'a'浓度，第6天下降。本研究结果表明，DOW的100％和50％稀释液可用于Chaetoceros sp。的强化培养。 与使用常规培养基的培养相比，生物量的生产可以在3天内实现。