Recruitment failure in Florida Keys Acropora palmata, a threatened Caribbean coral
Recruitment failure in Florida Keys Acropora palmata, a threatened Caribbean coral
复制标题
佛罗里达群岛的鹿角珊瑚（一种受威胁的加勒比珊瑚）的招募失败
作者：
Dana E Williams;Dana E Williams;Margaret W. Miller;K. Kramer
掌状鹿角珊瑚从目前濒危状态的恢复取决于补充，而现有的加勒比珊瑚种群研究对这一过程的记录很少。A.据认为，掌形藻非常适合通过由物理干扰（如中等强度的飓风）产生的碎片的补充而增殖。本研究监测15个150平方米的固定研究地块上佛罗里达键前礁无性和性招聘2004年至2007年。2005年7月至10月期间，有4场飓风经过佛罗里达礁群，给礁区带来23至33 m s−1的风速。飓风之后的调查记录了研究地块内估计活组织面积的平均损失为52%。种群中“分支”菌落的百分比从67%下降到42%，而“残余”菌落（站立骨骼上的孤立组织块）从11%增加到27%。虽然一些脱落的树枝仍然是松散的碎片，但在研究地块中观察到的380个碎片中，超过70%在飓风丹尼斯后3周死亡或迅速失去组织。在整个研究过程中，只有27个片段附着在基质上，形成了成功的无性繁殖。同时，在研究中观察到的18个新的小结壳菌落中，只有2个不是无性起源的（即，以前观察到的菌落或碎片的残余组织），因此可能是性招募。2005年的飓风季节造成了A. palmata从上佛罗里达键前礁的物理去除和随后的疾病样组织死亡的组合，并产生了一些新兵的性或无性起源。此外，由于缺乏分支（即，“无性繁殖力”）和活组织的总体损失。
Recovery of Acropora palmata from its currently imperiled status depends on recruitment, a process which is poorly documented in existing Caribbean coral population studies. A. palmata is thought to be well adapted to proliferate through the recruitment of fragments resulting from physical disturbances, such as moderate intensity hurricanes. This study monitored fifteen 150 m2 fixed study plots on the upper Florida Keys fore-reef for asexual and sexual recruitment from 2004 to 2007. Between July and October 2005, 4 hurricanes passed by the Florida Keys, producing wind speeds on the reef tract of 23 to 33 m s−1. Surveys following the hurricanes documented an average loss of 52% estimated live tissue area within the study plots. The percentage of “branching” colonies in the population decreased from 67% to 42% while “remnant” colonies (isolated patches of tissue on standing skeleton) increased from 11% to 27%. Although some detached branches remained as loose fragments, more than 70% of the 380 fragments observed in the study plots were dead or rapidly losing tissue 3 weeks after Hurricane Dennis. Over the course of the study, only 27 fragments became attached to the substrate to form successful asexual recruits. Meanwhile, of the 18 new, small encrusting colonies that were observed in the study, only 2 were not attributable to asexual origin (i.e., remnant tissue from colonies or fragments previously observed) and are therefore possible sexual recruits. In summary, the 2005 hurricane season resulted in substantial loss of A. palmata from the upper Florida Keys fore-reef from a combination of physical removal and subsequent disease-like tissue mortality, and yielded few recruits of either sexual or asexual origin. Furthermore, the asexual and sexual fecundity of the remaining population is compromised for the near future due to the lack of branches (i.e., “asexual fecundity”) and overall loss of live tissue.