Centro de Investigaciones Marinas, Universidad de La Habana. 16 # 114, Playa, 11300, Habana, Cuba.
Escuela Nacional de Estudios Superiores. Unidad Mérida. UNAM. Carretera Mérida-Tetiz km. 4.5. Ucú, CP97357, Yucatán, Mexico; Centro de Estudios Ambientales de Cienfuegos. Carretera Castillo de Jagua, Cienfuegos, Cuba.
Mar Environ Res. 2021 Oct;171:105477. doi: 10.1016/j.marenvres.2021.105477. Epub 2021 Sep 11.
We investigated stratigraphic changes in mollusk death assemblages and geochemistry in sediment cores from four seagrass beds and one unvegetated site in the Gulf of Guanahacabibes (GG), NW Cuba. There was a transition from mangrove to seagrass beds, associated with sea level rise ∼6000 years ago. Sediment accumulation rates during the last century showed a general rise, but increased sharply after ∼1980, likely because of human activities. The GG displayed overall high mollusk γ-diversity, and our estimate of 189 species is biased toward the low end. High β-diversity was driven by inter-site differences in grain size, vegetation cover, and nutrient input. Spatial heterogeneity within the basin influenced downcore abundance and diversity metrics, highlighting the influence of local drivers. Herbivorous gastropods dominated in seagrass beds and suspension feeder bivalves were dominant on sandy bottom. In the top parts of cores, species richness declined at two sites that were subject to high, human-mediated bulk sedimentation rates and eutrophication. Conservation measures are needed to preserve this hotspot of marine diversity.
我们研究了来自古巴西北部关纳哈卡比贝斯湾（Guanahacabibes Gulf，GG）的四个海草床和一个无植被区的沉积岩芯中软体动物死亡组合和地球化学的地层变化。这里存在着从红树林到海草床的转变，这与约 6000 年前的海平面上升有关。上个世纪的沉积积累率总体呈上升趋势，但自 1980 年左右以来急剧增加，这可能是由于人类活动造成的。GG 显示出整体上高的软体动物 γ-多样性，我们估计的 189 个物种偏向低值。高 β-多样性是由粒径、植被覆盖和养分输入的站点间差异驱动的。盆地内的空间异质性影响了核心内的丰度和多样性指标，突出了局部驱动因素的影响。在海草床中，草食性腹足类动物占主导地位，而在沙质底部，悬浮滤食性双壳类动物则占主导地位。在核心的顶部，两个受到高人为介导的大量沉积物沉降率和富营养化影响的地点的物种丰富度下降。需要采取保护措施来保护这个海洋多样性的热点地区。
