抄録
Abstract: Indoor experimental transplanting of Phyllospadix iwatensis to three aquaria under conditions of 0g(aq-1), 4g(aq-2), and 8g(aq-3)biweekly nutrient enrichment was conducted in order to quantify the role of nutrients in seagrass production. Nutrient concentrations(total N, total P, and NO3+NO2)in overlying sea water, porewater, and sediment were analyzed using standard chemical methods. Seagrass shoot and rhizome production was measured by a thread marking technique. The growth rates of leaf and rhizome were constant throughout the course of the experiment in aq-1, showed an acceleration in aq-2, and attained their highest levels in aq-3 due to the different nutrient conditions. Similarly, shoot density, in florescence production, reproductive effort, leaf area index(LAI), C, N, and P contents, photosynthetic pigment, and biomass were also varied greatly with nutrient level, in all cases with concentrations or rates remaining constant in aq-1, increasing or accelerating in aq-2, and reaching their highest levels in aq-3. These results show that nutrients are a strong factor influencing Phyllospadix iwatensis production.