QEIB: Energetic Cost of Burrowing

QEIB：挖掘的能量成本

• 批准号: 0642249
• 负责人: Mimi A Koehl
• 金额: $ 37.5万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0642249&HistoricalAwards=false
• 关键词: QEIB; Energetic; Cost; Burrowing

Marine sediments (mostly mud) cover 70% of Earth's surface and are inhabited by a diverse community of animals (including worms, clams). These animals are important links in marine food webs and are eaten by many commercially important fish. They also affect the fate of carbon in the ocean, not only because they process it metabolically, but also because their burrowing activities mix the sediment and affect the transport of materials between the water and the sea bottom. Therefore, burrowing animals play an important role in the global carbon cycle, and also affect the fates of nutrients and pollutants in marine habitats. In spite of the abundance of burrowing animals and their ecological importance, burrowing is surprisingly poorly understood compared to other forms of locomotion.This study investigates the physics and metabolism of how animals burrow through mud, focusing on polychaete worms, the abundant and ecologically-important marine relatives of earthworms. Dorgan recently modified a technique called "photoelastic stress analysis" for use with burrowing worms that will be employed in this study to measure the forces worms exert on the sediment while they burrow. Dorgan's work revealed that animals burrow by cracking mud rather than deforming it, leading to the prediction that metabolic costs of burrowing are much lower than previously believed. This study combines such mechanical analyses with measurements of metabolic rates of burrowing worms and of flux of materials through the sediment to elucidate how the mechanics of burrowing affects these processes for animals of different sizes burrowing in various types of sediments.These results will provide important information about the mechanisms and rates that burrowers affect the flux of materials such as carbon or pollutants through the muddy sea floor, and will also increase our understanding of the mechanisms by which animals (and biomimetic robots) can move through sediments. The PI will continue to recruit and encourage young scientists, especially women, and will continue to teach courses on professional development for young scientists. She is a great communicator to the public, and will actively participate in outreach and education based on this research. She will also continue her mentoring students with learning disabilities; she has dyslexia and is able to share techniques that help young scientists with similar and other disabilities.

海洋沉积物(主要是泥)覆盖了地球表面的70%，居住着各种各样的动物群落(包括蠕虫、蛤)。这些动物是海洋食物网中的重要纽带，被许多具有重要商业价值的鱼类吃掉。它们还影响海洋中碳的命运，不仅是因为它们对碳进行新陈代谢，还因为它们的挖掘活动混合了沉积物，影响了水和海底之间的物质运输。因此，穴居动物在全球碳循环中扮演着重要的角色，也影响着海洋生物栖息地中营养物质和污染物的命运。尽管洞穴动物的数量和它们在生态上的重要性，但与其他形式的运动相比，人们对洞穴动物的了解令人惊讶地少之又少。本研究调查了动物如何在泥浆中挖洞的物理和新陈代谢，重点是多毛类蠕虫，这是蚯蚓的丰富和生态重要的海洋近亲。道根最近修改了一种名为“光弹性应力分析”的技术，用于研究穴居蠕虫，这项研究将用来测量蠕虫在洞穴中对沉积物施加的力。道根的研究揭示，动物通过裂开泥土而不是使泥土变形来挖洞，这导致了预测，挖洞的新陈代谢成本比之前认为的要低得多。这项研究将这种力学分析与对穴居蠕虫的代谢率和通过沉积物的物质通量的测量相结合，以阐明洞穴机制如何影响不同大小的动物在不同类型的沉积物中挖掘的这些过程。这些结果将提供关于洞穴者影响物质(如碳或污染物)通过泥泞海底的通量的机制和速率的重要信息，并将增加我们对动物(和仿生机器人)在沉积物中移动的机制的理解。青年科学家协会将继续招聘和鼓励青年科学家，特别是妇女，并将继续为青年科学家讲授专业发展课程。她是一位伟大的公众沟通者，并将积极参与基于这项研究的外展和教育。她还将继续指导有学习障碍的学生；她有诵读困难，并能够分享帮助有类似和其他残疾的年轻科学家的技术。