Selective preservation of organic-walled dinoflagellate cysts as a tool to quantify past net primary production and bottom water oxygen concentrations
Selective preservation of organic-walled dinoflagellate cysts as a tool to quantify past net primary production and bottom water oxygen concentrations
复制标题
有机壁甲藻包囊的选择性保存作为量化过去净初级生产力和底层水氧浓度的工具
DOI：
10.1016/j.margeo.2006.10.023
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发表时间：
2007
期刊：
影响因子：
2.9
通讯作者：
U. Holzwarth
中科院分区：
文献类型：
--
作者：
K. Zonneveld;F. Bockelmann;U. Holzwarth
为了了解海洋在全球碳循环中的作用，需要详细了解海洋碳循环中的关键过程;上层海洋的生物生产，生产的物质向深海的出口以及海洋沉积物中的碳储存。这些过程的量化需要分离的信号净初级生产和反映在化石沉积物中的有机质衰变率。本研究探讨了有机壁甲藻孢囊物种的降解速率的巨大差异，以分离这些降解和生产力信号。为此，积累率已知是耐（R-孢囊）或敏感（S-孢囊）有氧降解的62个网站的孢囊物种进行比较，平均每年叶绿素a，海面温度，海面盐度，硝酸盐和磷酸盐浓度的上层沃茨和深水氧气浓度。此外，敏感的孢囊的降解，表示为降解常数k和反应时间t，已与底层水[O2]。所研究的沉积物取自阿拉伯海、西北非洲边缘（北大西洋）、西赤道大西洋/加勒比海、西南非洲边缘（南大西洋）和南大洋（大西洋部分）。在（a）R-孢囊的积累速率和上层水叶绿素a浓度、（B）S-孢囊和底层水[O2]的积累速率以及（c）S-孢囊（kt）和底层水[O2]的降解速率之间观察到显著的关系。在所有置信区间上，S-孢囊积累速率与叶绿素a浓度、海表温度（SST）、海表盐度（SSS）、磷酸盐浓度（P）和硝酸盐浓度（N）之间的关系非常弱或明显不显著;（2）R-孢囊积累速率与底层水[O2]、SST、SSS、P和N之间的关系，（3）kt与水深之间。N与P、N、P与叶绿素a、氧与水深之间存在协方差。校正此协方差不会影响上述关系的显著性。甲藻孢囊降解估计过去的净初级生产力和深海通风的可能适用性进行了讨论。
To understand the role of the ocean within the global carbon cycle, detailed information is required on key-processes within the marine carbon cycle; bio-production in the upper ocean, export of the produced material to the deep ocean and the storage of carbon in oceanic sediments. Quantification of these processes requires the separation of signals of net primary production and the rate of organic matter decay as reflected in fossil sediments. This study examines the large differences in degradation rates of organic-walled dinoflagellate cyst species to separate these degradation and productivity signals. For this, accumulation rates of cyst species known to be resistant (R-cysts) or sensitive (S-cysts) to aerobic degradation of 62 sites are compared to mean annual chlorophyll-a, sea-surface temperature, sea-surface salinity, nitrate and phosphate concentrations of the upper waters and deep-water oxygen concentrations. Furthermore, the degradation of sensitive cysts, as expressed by the degradation constant k and reaction time t, has been related to bottom water [O2]. The studied sediments were taken from the Arabian Sea, north-western African Margin (North Atlantic), western-equatorial Atlantic Ocean/Caraibic, south-western African margin (South Atlantic) and Southern Ocean (Atlantic sector). Significant relationships are observed between (a) accumulation rates of R-cysts and upper water chlorophyll-a concentrations, (b) accumulation rates of S-cysts and bottom water [O2] and (c) degradation rates of S-cysts (kt) and bottom water [O2]. Relationships that are extremely weak or are clearly insignificant on all confidence intervals are between (1) S-cyst accumulation rates and chlorophyll-a concentrations, sea-surface temperature (SST), sea-surface salinity (SSS), phosphate concentrations (P) and nitrate concentrations (N), (2) between R-cyst accumulation rates and bottom water [O2], SST, SSS, P and N, and between (3) kt and water depth. Co-variance is present between the parameters N and P, N, P and chlorophyll-a, oxygen and water depth. Correcting for this co-variance does not influence the significance of the relationship given above. The possible applicability of dinoflagellate cyst degradation to estimate past net primary production and deep ocean ventilation is discussed.