Net ecosystem production and carbon dioxide fluxes in the Scheldt estuarine plume
Net ecosystem production and carbon dioxide fluxes in the Scheldt estuarine plume
复制标题
斯海尔德河口羽流中的净生态系统生产和二氧化碳通量
作者：
Alberto Borges;Kevin Ruddick;L. Schiettecatte;B. Delille
背景本文使用连续 4 年测量斯海尔德河口羽流中二氧化碳分压 (pCO2) 的时间序列来估算净生态系统生产 (NEP)。结果斯海尔德河口羽流中的 NEP 是根据溶解无机碳 (DIC) 的时间变化来估算的。 NEP 强烈的季节性变化与之前关于该地区有机碳动态的报告一致。这些变化与浮游植物的连续繁殖有关，这些浮游植物在一年中的其余时间部分地滋养了季节性变化的异养生物。在每年的时间尺度上，斯海尔德河口羽流表现为一个净异养系统，由来自斯海尔德河口内河口和比利时海岸的有机碳输入维持。在时间序列的某一年中，河口羽流每年都表现为净自养系统。这种异常的生态系统代谢行为似乎是影响春季浮游植物繁殖的自下而上因素综合作用的结果（养分输送增加和更有利的光照条件）。这种净自养似乎导致了有机碳的短暂aa积累，最有可能在沉积物中，从而在第二年提供了更强的异养作用。结论目前的工作强调了使用pCO2数据在高度动态的沿海环境中得出NEP的详细季节性估计的潜力。这些可用于确定由于自然气候波动或人为影响变化而导致的 NEP 潜在年际变化。
BackgroundA time series of 4 consecutive years of measurements of the partial pressure of CO2 (pCO2) in the Scheldt estuarine plume is used here to estimate net ecosystem production (NEP).ResultsNEP in the Scheldt estuarine plume is estimated from the temporal changes of dissolved inorganic carbon (DIC). The strong seasonal variations of NEP are consistent with previous reports on organic carbon dynamics in the area. These variations are related to successive phytoplankton blooms that partly feed seasonally variable heterotrophy the rest of the year. On an annual time scale the Scheldt estuarine plume behaves as a net heterotrophic system sustained with organic carbon input from the Scheldt inner estuary and the Belgian coast. During one of the years of the time-series the estuarine plume behaved annually as a net autotrophic system. This anomalous ecosystem metabolic behaviour seemed to result from a combination of bottom-up factors affecting the spring phytoplankton bloom (increased nutrient delivery and more favourable incoming light conditions). This net autotrophy seemed to lead to a transient aa accumulation of organic carbon, most probably in the sediments, that fed a stronger heterotrophy the following year.ConclusionThe present work highlights the potential of using pCO2 data to derive detailed seasonal estimates of NEP in highly dynamic coastal environments. These can be used to determine potential inter-annual variability of NEP due to natural climatic oscillations or due to changes in anthropogenic impacts.