Climate-driven trends in contemporary ocean productivity
Climate-driven trends in contemporary ocean productivity
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DOI：
10.1038/nature05317
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发表时间：
2006-12-07
期刊：
影响因子：
64.8
通讯作者：
Boss, Emmanuel S.
中科院分区：
文献类型：
--
作者：
Behrenfeld, Michael J.;O'Malley, Robert T.;Boss, Emmanuel S.
海洋浮游植物的光合作用约占生物圈净初级生产力 (NPP)(1,2) 的一半，是生物和无机种群之间碳循环的重要环节。每天，超过一亿吨以二氧化碳形式存在的碳被这些上层海洋中无处不在的微观植物固定在有机物质中，并且每天都有类似数量的有机碳通过下沉和放牧转移到海洋生态系统中。浮游植物生物量和 NPP 的分布由光和营养物（氮、磷酸盐、铁）的可用性决定。这些生长限制因素反过来又受到海洋环流、混合层动力学、上升流、大气尘埃沉积和太阳周期等物理过程的调节。海洋颜色的卫星测量提供了一种量化全球范围内海洋生产力并将其变化与环境因素联系起来的方法。在这里，我们描述了过去十年从太空检测到的全球海洋 NPP 变化。这一时期的主要特点是 NPP 最初增加每年 1,930 太克碳 (Tg C yr(-1))，随后长期平均减少 190 Tg C yr(-1)。这些趋势是由广阔的低纬度分层海洋中发生的变化驱动的，并且与同时发生的气候变化密切相关。物理环境和海洋生物学之间的这种联系通过上层海洋温度和分层的变化发挥作用，从而影响浮游植物生长的营养物质的可用性。在 1999 年之后的变暖期间观察到的海洋生产力下降，为未来气候变化如何改变海洋食物网提供了见解。
Contributing roughly half of the biosphere's net primary production (NPP)(1,2), photosynthesis by oceanic phytoplankton is a vital link in the cycling of carbon between living and inorganic stocks. Each day, more than a hundred million tons of carbon in the form of CO2 are fixed into organic material by these ubiquitous, microscopic plants of the upper ocean, and each day a similar amount of organic carbon is transferred into marine ecosystems by sinking and grazing. The distribution of phytoplankton biomass and NPP is defined by the availability of light and nutrients ( nitrogen, phosphate, iron). These growth-limiting factors are in turn regulated by physical processes of ocean circulation, mixed-layer dynamics, upwelling, atmospheric dust deposition, and the solar cycle. Satellite measurements of ocean colour provide a means of quantifying ocean productivity on a global scale and linking its variability to environmental factors. Here we describe global ocean NPP changes detected from space over the past decade. The period is dominated by an initial increase in NPP of 1,930 teragrams of carbon a year (Tg C yr(-1)), followed by a prolonged decrease averaging 190 Tg C yr(-1). These trends are driven by changes occurring in the expansive stratified low-latitude oceans and are tightly coupled to coincident climate variability. This link between the physical environment and ocean biology functions through changes in upper-ocean temperature and stratification, which influence the availability of nutrients for phytoplankton growth. The observed reductions in ocean productivity during the recent post-1999 warming period provide insight on how future climate change can alter marine food webs.