Tropicalization may invert trophic state and carbon budget of shallow temperate rocky reefs
Tropicalization may invert trophic state and carbon budget of shallow temperate rocky reefs
复制标题
热带化可能会反转浅温带岩礁的营养状态和碳预算
DOI：
10.1111/1365-2745.13329
复制
发表时间：
2020
影响因子：
5.5
通讯作者：
G. Rilov
中科院分区：
文献类型：
--
作者：
O. Peleg;T. Guy‐Haim;E. Yeruham;J. Silverman;G. Rilov
全球变暖调节并维持温带海洋生态系统的热带化。最近的研究表明，这一过程导致温带珊瑚礁从藻类森林转变为裸露的非树冠状态。有人认为这些变化将对生态系统功能产生重大影响。在这项研究中，我们现场测试了热带化如何影响快速变暖和高度入侵的地中海东南部浅海珊瑚礁的栖息地供应功能和碳周转。在单个浅礁上，我们对三个栖息地的这些功能进行了测量：逐渐减少的原生褐藻（Cystoseira）森林、占主导地位的草皮（由过度放牧热带兔鱼形成）和以红色钙化藻（Galaxaura rugosa）为主的扩张的热带灌木。藻类森林是一个自养净碳汇，为高物种多样性和最大的群落生物量提供了栖息地。裸露的草皮是异养的，为最低的物种多样性和群落生物量提供了栖息地。虽然热带灌木的多样性与藻类森林一样高，但其生物量较低，并且充当异养净碳源。合成。我们的研究举例说明了热带化驱动的政权转变对浅温带岩礁可能产生的功能后果，以及这些后果如何逆转净营养状态和碳平衡。
Global warming mediates and maintains the tropicalization of temperate marine ecosystems. Recent studies have demonstrated that this process causes shifts from algal forests to denuded non‐canopy states in temperate reefs. It has been suggested that these changes would incur significant consequences to ecosystem functioning. In this study, we tested how tropicalization affects habitat‐provisioning functions and carbon turnover of a shallow reef in the fast‐warming and highly invaded southeastern Mediterranean Sea, in‐situ. On a single shallow reef, we conducted measurements of these functions in three habitats: dwindling native brown algal (Cystoseira) forest, dominant turf (formed by overgrazing of tropical rabbitfish) and expanding tropical shrubs dominated by red calcifying algae (Galaxaura rugosa). Algal forest was an autotrophic net carbon sink and provided habitat for high species diversity and the largest community biomass. The denuded turf was heterotrophic and provided habitat for the lowest species diversity and community biomass. While diversity was as high in tropical shrubs as in the algal forest, it had lower biomass and functioned as a heterotrophic net carbon source. Synthesis. Our study exemplifies possible functional consequences of tropicalization‐driven regime shifts on shallow temperate rocky reefs, and how these can invert the net trophic state and carbon balance.