粮食供应与需求之间的长期差异在东北太平洋深部地区
1Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0202, USA. Marine and Environmental Studies Program, University of San Diego, 5998 Alcala Park, Sa.
Science (New York, N.Y.)
|May 15, 1999
概括
在东北太平洋,深海的食物供应正在减少. 一项为期7年的研究发现,沉降的微粒有机碳 (POC) 减少,影响了沉积物社区的氧气消耗 (SCOC) 和深海生态系统.
科学领域:
- 海洋生物学 海洋生物学
- 海洋学 海洋学 海洋学
- 深海生态 深海生态
背景情况:
- 的东北太平洋是一个深海环境,以有限的食物供应为特征.
- 沉积物社区的氧气消耗 (SCOC) 作为深海食物需求的代理.
- 沉没的微粒有机碳 (POC) 是深海的主要食物供应来源.
研究的目的:
- 评估北太平洋深东部地区粮食供应 (POC) 和粮食需求 (SCOC) 的长期趋势.
- 研究表面海洋条件与深海食物供应之间的关系.
- 评估观察到的趋势对深海生态系统和地球化学循环的潜在影响.
主要方法:
- 进行了为期7年的研究,以监测POC流量和SCOC.
- 分析了海洋表面温度和浮游生物质的数据.
- 计算了POC与SCOC的比值,以评估相对于需求的粮食供应.
主要成果:
- 在的东北太平洋地区,观察到长期出现的粮食供应短缺.
- 在1989年至1996年期间,POC:SCOC比率下降了52%,至59%.
- 这种下降可能与海面温度升高和地表水中的浮游生物质减少有关,从而减少了POC出口.
结论:
- 北太平洋东部的深海正经历着粮食供应的减少.
- 继续减少POC出口可能会显著改变深海地质化学循环.
- 观察到的趋势可能会导致深海社区的结构和动态发生深刻变化.
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