School of the Earth, Ocean & Environment, University of South Carolina, Columbia, SC 29208, USA:
Southern California Coastal Ocean Observing System, Scripps Institution of Oceanography, 8880 Biological Grade, La Jolla, CA 92093, USA.
Toxins (Basel). 2018 Nov 17;10(11):480. doi: 10.3390/toxins10110480.
Water column bulk abundance and the dissolved and particulate domoic acid (DA) concentrations were measured in the Santa Barbara Basin (SBB), California from 2009⁻2013 and compared to bulk cell abundance and DA concentrations and fluxes in sediment traps moored at 147 m and 509 m. abundance throughout the study period was spatially and temporally heterogeneous (<200 cells L to 3.8 × 10⁶ cells L, avg. 2 × 10⁵ ± 5 × 10⁵ cells L) and did not correspond with upwelling conditions or the total DA (tDA) concentration, which was also spatially and temporally diverse (<1.3 ng L to 2.2 × 10⁵ ng L, avg. 7.8 × 10³ ± 2.2 × 10⁴ ng L). We hypothesize that the toxicity is likely driven in part by specific species as well as bloom stage. Dissolved (dDA) and particulate (pDA) DA were significantly and positively correlated ( < 0.01) and both comprised major components of the total DA pool (pDA = 57 ± 35%, and dDA = 42 ± 35%) with substantial water column concentrations (>1000 cells L and tDA = 200 ng L) measured as deep as 150 m. Our results highlight that dDA should not be ignored when examining bloom toxicity. Although water column abundance and pDA concentrations were poorly correlated with sediment trap abundance and fluxes, DA toxicity is likely associated with senescent blooms that rapidly sink to the seafloor, adding another potential source of DA to benthic organisms.
2009 年至 2013 年期间，在加利福尼亚州的圣巴巴拉盆地（SBB）测量了水柱总体丰度以及溶解态和颗粒态软骨藻酸（DA）浓度，并与在 147 米和 509 米处系泊的沉积物捕获器中的水柱细胞总体丰度以及 DA 浓度和通量进行了比较。整个研究期间，水柱总体丰度在空间和时间上存在异质性（<200 个细胞/L 至 3.8×106 个细胞/L，平均值为 2×105±5×105 个细胞/L），与上升流条件或总 DA（tDA）浓度无关，后者也在空间和时间上存在多样性（<1.3ng/L 至 2.2×105ng/L，平均值为 7.8×103±2.2×104ng/L）。我们假设，这种毒性可能部分由特定物种以及浮游植物爆发阶段所驱动。溶解态（dDA）和颗粒态（pDA）DA 呈显著正相关（<0.01），两者均构成总 DA 库的主要组成部分（pDA=57±35%，dDA=42±35%），水柱中的浓度相当高（>1000 个细胞/L 和 tDA=200ng/L），在 150m 深处也有相当高的浓度。我们的研究结果表明，在研究浮游植物爆发毒性时，不应忽视溶解态 DA。尽管水柱总体丰度和 pDA 浓度与沉积物捕获器中的细胞总体丰度和通量相关性较差，但 DA 毒性可能与快速下沉到海底的衰老浮游植物爆发有关，这为底栖生物增加了另一个 DA 的潜在来源。
