MRI: Development of an integrated wide-band acoustical backscattering and large-area camera imaging instrument for studies of mesopelagic and bathypelagic ecosystems

MRI：开发集成宽带声学后向散射和大面积相机成像仪器，用于研究中层和深海生态系统

• 批准号: 1626087
• 负责人: Andone Lavery
• 金额: $ 80.5万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1626087&HistoricalAwards=false
• 关键词: MRI; Development; integrated; wide; band

The mesopelagic and bathypelagic zones together span ocean depths from approximately 200 meters to 4,000 meters below the surface and form one of the largest habitats on Earth. These zones are home to diverse communities of zooplankton and micronekton, including a variety of small fishes, cephalopods, crustaceans, and gelatinous organisms. Yet relatively little is known about the biology, adaptations, abundance, biomass, and distribution of the inhabitants of these deep and dark ecosystems. In general, such organisms are difficult to sample by conventional nets due to a combination of the patchiness of the organisms, avoidance of the nets by more mobile organisms, difficulties in sampling synoptically at such depths using nets, and the destruction of fragile species by the nets. However, recent evidence suggests that the global biomass estimates of micronektonic fish in the mesopelagic zone based on sampling by nets may be an order of magnitude too low and suggests a strong coupling between surface production and mesopelagic fish biomass, hinting at a previously under-appreciated biogeochemical role. This project will fill the current technological void for characterizing mesopelagic and bathypelagic ecosystems by developing a combined acoustical and optical ecosystem assessment instrument for quantifying the biomass and distribution of zooplankton and micronekton in the mesopelagic and bathypelagic zones. This instrument is particularly well suited to understanding the diverse communities of zooplankton and micronekton in relation to environmental variability, such as meso-scale oceanic eddies, fronts, and upwelling regions, and abrupt topography, such as canyons, seamounts, and shelf breaks. Impacts from this research will extend from basic research problems underpinning science-based fisheries management and decision making, to broader societally relevant problems. The project outcomes will most likely guide the development of future commercially available instruments for fisheries and ecosystem assessment for users from both the scientific and fisheries research communities.This project will develop a combined wide-band acoustic scattering and two-scale large-area camera imaging towed instrument, rated to depths as great as 2,000 m, integrated with environmental sensors that can address many of the challenges associated with sampling in the mesopelagic and bathypelagic zones. This instrument capitalizes on emerging broadband acoustical approaches. The acoustic frequencies will span 1-450 kHz almost continuously, simultaneously providing ?full spectrum? information on zooplankton and micronekton, with the lower frequencies optimized for resonance classification of gas-bearing organism, such as myctophids and siphonophores, and the higher frequencies optimized for spectral classification of organism without gas-inclusions, such as euphausiids and salps. The two-scale camera system will provide images of these organisms over a large area for taxa/species-level classification as well as behavioral observation, including imaging larger and mobile micronekton, and will ground-truth the synoptic acoustic data.

中层和深层的海洋深度从海面以下约200米到4 000米，是地球上最大的生境之一。这些区域是各种浮游动物和微浮游生物群落的家园，包括各种小鱼、头足类、甲壳类和凝胶状生物。 然而，人们对这些深暗生态系统的生物学、适应性、丰度、生物量和居民分布知之甚少。一般而言，由于生物体的斑块性、更多移动的生物体避开渔网、在这种深度使用渔网进行天气采样的困难以及渔网对脆弱物种的破坏等因素的结合，这些生物体很难用传统渔网进行采样。然而，最近的证据表明，根据渔网取样对中层微浮游鱼类的全球生物量估计可能太低，并表明表层生产和中层鱼类生物量之间存在很强的耦合，暗示了以前未得到充分重视的海洋地球化学作用。该项目将开发一种综合声学和光学生态系统评估工具，用于量化中层和深层浮游动物和微浮游生物的生物量和分布，从而填补目前在中层和深层生态系统特征方面的技术空白。该仪器特别适合于了解浮游动物和微浮游生物的不同群落与环境变异的关系，如中尺度海洋涡旋、锋面和上升流区域，以及峡谷、海山和陆架断裂等陡峭地形。 这项研究的影响将从支持以科学为基础的渔业管理和决策的基础研究问题扩展到更广泛的社会相关问题。该项目的成果很有可能指导今后为科学界和渔业研究界的用户开发渔业和生态系统评估商用仪器，该项目将开发一种宽带声散射和双尺度大面积摄像成像拖曳式综合仪器，其额定深度可达2 000米，该系统与环境传感器相结合，可以解决与中层和深层采样有关的许多挑战。该仪器利用了新兴的宽带声学方法。声波频率将跨越1-450千赫几乎连续，同时提供？全光谱？该系统还提供了关于浮游动物和微浮游生物的信息，低频优化用于含气生物的共振分类，如myctophids和管水母，高频优化用于不含气包体的生物的光谱分类，如磷虾和海鞘。双尺度照相机系统将提供这些生物在大面积上的图像，用于分类/物种一级的分类以及行为观察，包括对较大的和移动的微浮游生物成像，并将对天气声学数据进行地面实况。