In Saroma-ko Lagoon, where scallop aquaculture is a thriving commercial activity, monitoring primary production is essential for determining the amount of scallops that can be farmed. Using the primary production data obtained so far, we calculated Ψ, an index of water-column light utilization efficiency, and clarified its seasonal variation. Ψ tended to be lower in the spring bloom season (February–April), and higher in the late autumn to winter (October–December). Low chlorophyll-normalized production, an index of growth rate, resulted in lower values, while low daily irradiance resulted in higher values. The values of Ψ from our study had a range of 0.05–1.42 gC gChl-a−1 mol photons−1 m2 (N = 56). These values were within the previously reported range of 0.07–1.92 (gC gChl-a−1 mol photons−1 m2) for seawater and fresh water worldwide. Therefore, it is likely that Ψ varies from 0.05–2 gC gChl-a−1 mol photons−1 m2, being affected by conditions of phytoplankton growth and sunlight intensity, regardless of whether samples are collected from seawater or fresh water. Using the median Ψ value of 0.45 gC gChl-a−1 mol photons−1 m2 obtained in this study, primary production was 0.3–3.5 times the actual production at Saroma-ko Lagoon. Using this method, primary production can be easily and constantly monitored, facilitating the sustainable development of scallop aquaculture.

中文翻译：

---

Saroma-ko Lagoon初级生产的水柱光利用效率的季节变化

在佐吕间湖泻湖，扇贝养殖是一项蓬勃发展的商业活动，监测初级生产对于确定可以养殖的扇贝数量至关重要。利用迄今为止获得的初级生产数据，我们计算了水柱光利用效率指数Ψ，并阐明了其季节性变化。Ψ 在春季开花季节（2 月至 4 月）趋于较低，而在深秋至冬季（10 月至 12 月）则较高。低叶绿素标准化产量（生长速率指数）导致值较低，而低日辐照度导致值较高。我们研究的 Ψ 值范围为 0.05–1.42 gC gChl-a-1摩尔光子-1米2（N = 56）。这些值在先前报道的 0.07-1.92 范围内（gC gChl-a-1摩尔光子-1米2) 用于全世界的海水和淡水。因此，Ψ 很可能在 0.05–2 gC gChl-a 之间变化-1摩尔光子-1米2，受浮游植物生长条件和日照强度的影响，无论样品是从海水还是淡水中采集的。使用 0.45 gC gChl-a 的 Ψ 中值-1摩尔光子-1米2在这项研究中获得的初级产量是 Saroma-ko Lagoon 实际产量的 0.3-3.5 倍。使用这种方法，可以轻松、持续地监测初级生产，促进扇贝养殖的可持续发展。