科學家報告說,，增加大氣二氧化碳可能改變太平洋中最大的捕食者之一的洪堡烏賊的新陳代謝和行為,。洪堡烏賊（Dosidicus gigas）見于太平洋熱帶東部地區(qū)，重量可達50公斤,。
Rui Rosa和Brad Seibel收集了來自加利福尼亞灣的洪堡烏賊,，從而調查變化的氧氣和二氧化碳濃度導致的海洋酸化對動物的影響。此前的研究提示,，氣候變化可能導致海洋中的二氧化碳增加，并形成碳酸,。在他們的船上進行的流動腔實驗中,，這組作者發(fā)現洪堡烏賊可以減緩它們的新陳代謝，僅使用非常少量的氧,。這種烏賊因此可以在白天下潛到水下175米的缺氧區(qū)域,。在夜間，這種烏賊依靠海面附近富含氧氣的海水,。然而,，預計到2100年海面的海水具有更高的二氧化碳濃度，這可能改變深處的低氧海水和表面酸化海水之間的可生活窗口,。
這組科學家說,，結果將是這種烏賊可能變得昏睡，因此更容易被捕食者捕獲,，比目前更難抓到獵物,，這可能迫使它們遷徙到別處,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS December 15, 2008, doi: 10.1073/pnas.0806886105
Synergistic effects of climate-related variables suggest future physiological impairment in a top oceanic predator
Rui Rosa1 and Brad A. Seibel
Department of Biological Sciences, University of Rhode Island, 100 Flagg Road, Kingston, RI 02881
By the end of this century, anthropogenic carbon dioxide (CO2) emissions are expected to decrease the surface ocean pH by as much as 0.3 unit. At the same time, the ocean is expected to warm with an associated expansion of the oxygen minimum layer (OML). Thus, there is a growing demand to understand the response of the marine biota to these global changes. We show that ocean acidification will substantially depress metabolic rates (31%) and activity levels (45%) in the jumbo squid, Dosidicus gigas, a top predator in the Eastern Pacific. This effect is exacerbated by high temperature. Reduced aerobic and locomotory scope in warm, high-CO2 surface waters will presumably impair predator–prey interactions with cascading consequences for growth, reproduction, and survival. Moreover, as the OML shoals, squids will have to retreat to these shallower, less hospitable, waters at night to feed and repay any oxygen debt that accumulates during their diel vertical migration into the OML. Thus, we demonstrate that, in the absence of adaptation or horizontal migration, the synergism between ocean acidification, global warming, and expanding hypoxia will compress the habitable depth range of the species. These interactions may ultimately define the long-term fate of this commercially and ecologically important predator.
