Temporal variations in microbenthic metabolism and inorganic nitrogen fluxes in sandy and muddy sediments of a tidally dominated bay in the northern Wadden Sea
Temporal variations in microbenthic metabolism and inorganic nitrogen fluxes in sandy and muddy sediments of a tidally dominated bay in the northern Wadden Sea
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瓦登海北部潮汐主导海湾的沙质和泥质沉积物中微生物代谢和无机氮通量的时间变化
DOI：
10.1007/bf02908717
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
K. Jensen
中科院分区：
文献类型：
--
作者：
E. Kristensen;M. Jensen;K. Jensen
控制底栖生物代谢（O2通量）和溶解无机氮（DIN）通量的季节性变化的因素进行了研究，在12-14个月期间在三个潮间带瓦登海站。由于通量测量是在小规模实验室核心培养中进行的，其结果主要与微型底栖生物群落（微藻、细菌、微型、小型和小型大型动物）有关，不能被视为瓦登海整个底栖生物群落的代表。此外，必须强调的是，在白天模拟期间的光强度是恒定的，并且在任何时候都是饱和的。底栖生物初级生产力和摄氧量似乎与温度有关，“季节Q10”分别为1.7-1.8和2.7-4.3。淹没对氧通量没有影响，证明了类似的沉积物呼吸和无水覆盖。较强的温度依赖性的初级生产力在泥比在桑迪沉积物表明，在后者的整体控制可能是复杂的，由于大型底栖动物放牧和养分供应等因素。底栖呼吸作用可能不仅受温度控制，因为沉积有机质含量与温度和底栖呼吸作用均显著相关。高潮间带桑迪沉积物的年总初级生产量分别比低潮间带桑迪和淤泥质沉积物高10%和50%。由于泥质沉积物中的底栖生物群落年呼吸量是桑迪沉积物中的2倍，因此前者的年净初级生产量约为0，后者为17-19 mol C m−2 yr−1。然而，异养的贡献较大的动物组成部分，以及去除有机碳的波浪和潮流，这是不包括在这里，可能会平衡的预算在桑迪站。有没有或只有微弱的关系（光明和黑暗）DIN交换和温度，沉积有机质含量，氧通量等因素。与营养盐通量相关的因素，例如上覆水中的反硝化作用和营养盐浓度，可能阻碍了任何此类关系。事实上，DIN通量在所有三个站出现强烈控制DIN浓度在上覆水。在每年的基础上，沉积物似乎是一个净汇DIN。
Factors controlling seasonal variations in benthic metabolism (O2 flux) and dissolved inorganic nitrogen (DIN) fluxes were examined during a 12–14 month period at three intertidal Wadden Sea stations. Since the flux measurements were made as small-scale laboratory core incubations, the results are primarily related to the microbenthic community (microalgae, bacteria, micro-, meio- and small macrofauna) and cannot be considered representative of the total benthic community in the Wadden Sea. Furthermore, it has to be emphasized that light intensity during day-time simulations were constant and saturating at all times. Benthic primary production and oxygen uptake appeared to be temperature dependent with a ‘seasonal Q10’ of 1.7–1.8 and 2.7–4.3, respectively. Inundation had no effect on oxygen fluxes as evidenced by similar sediment respiration with and without water cover. A stronger temperature dependence of primary production in muddy than in sandy sediment indicated that the overall control in the latter may be complex due to factors like macrofaunal grazing and nutrient availability. Benthic respiration may not be controlled by temperature alone, as sedimentary organic matter content correlated significantly with both temperature and benthic respiration. Annual gross primary production in high intertidal sandy sediment was 10 and 50% higher than in low intertidal sandy and muddy sediments, respectively. Since annual benthic community respiration was 2 times higher in muddy than sandy sediments, the annual net primary production was about 0 in the former and 17–19 mol C m−2 yr−1 in the latter. However, heterotrophic contribution by larger faunal components as well as removal of organic carbon by waves and tidal currents, which are not included here, may balance the budget at the sandy stations. There was no or only weak relationships between (light and dark) DIN exchange and factors like temperature, sedimentary organic content, and oxygen fluxes. Factors related to nutrient fluxes, such as denitrification and nutrient concentration in the overlying water, may have hampered any such relationships. In fact, DIN fluxes at all three stations appeared to be strongly controlled by DIN concentrations in the overlying water. On an annual basis, the sediment appeared to be a net sink for DIN.