Randall Carly J, Szmant Alina M
Center for Marine Science, University of North Carolina Wilmington, 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, USA.
Biol Bull. 2009 Dec;217(3):269-82. doi: 10.1086/BBLv217n3p269.
Elevated seawater temperatures during the late summer have the potential to negatively affect the development and survivorship of the larvae of reef corals that are reproductive during that time of year. Acropora palmata, a major Caribbean hermatype, reproduces annually during August and September. A. palmata populations have severely declined over the past three decades, and recovery will require high recruitment rates. Such recruitment will be limited if larval supply is reduced by elevated temperatures. The effects of elevated temperatures on development, survival, and larval settlement of A. palmata were investigated by culturing newly fertilized eggs at temperatures ranging from 27.5 to 31.5 degrees C. Development was accelerated and the percentage of developmental abnormalities increased at higher temperatures. Embryo mortality peaked during gastrulation, indicating that this complex developmental process is particularly sensitive to elevated temperatures. Larvae cultured at 30 and 31.5 degrees C experienced as much as an 8-fold decrease in survivorship compared to those at 28 degrees C. Additionally, settlement was 62% at 28 degrees C compared to 37% at 31.5 degrees C. These results indicate that embryos and larvae of A. palmata will be negatively affected as sea surface temperatures continue to warm, likely reducing recruitment and the recovery potential of A. palmata on Caribbean reefs.
夏末海水温度升高有可能对每年这个时期进行繁殖的珊瑚礁幼虫的发育和存活产生负面影响。鹿角珊瑚是加勒比地区主要的造礁珊瑚，每年8月和9月进行繁殖。在过去三十年里，鹿角珊瑚的数量急剧下降，其恢复需要高补充率。如果水温升高导致幼虫供应减少，那么这种补充将会受到限制。通过在27.5至31.5摄氏度的温度范围内培养新受精的卵，研究了水温升高对鹿角珊瑚发育、存活和幼虫附着的影响。在较高温度下，发育加速且发育异常的百分比增加。胚胎死亡率在原肠胚形成期间达到峰值，这表明这个复杂的发育过程对水温升高特别敏感。与在28摄氏度下培养的幼虫相比，在30摄氏度和31.5摄氏度下培养的幼虫存活率降低了多达8倍。此外，在28摄氏度下幼虫附着率为62%，而在31.5摄氏度下为37%。这些结果表明，随着海面温度持续升高，鹿角珊瑚的胚胎和幼虫将受到负面影响，这可能会减少加勒比珊瑚礁上鹿角珊瑚的补充率及其恢复潜力。
