概括
来自河流的全球海洋二氧化输入量被修订为每年6.1特拉莫尔,以平衡来自海洋沉积物的输出量. 这项研究改进了对海洋循环的理解.
科学领域:
- 地质化学 地质化学
- 海洋学 海洋学 海洋学
- 生物地质化学循环的过程
背景情况:
- 全球循环对于海洋生态系统和地质过程至关重要.
- 之前对酸输入海洋的估计缺乏准确性.
研究的目的:
- 修订和量化酸对世界海洋的净输入量.
- 为了平衡这些输入与海洋沉积物中的生物基性的输出.
- 为了估计总生物质生产和保存率.
主要方法:
- 汇编和分析河流酸度.
- 在海洋沉积物中生物性石埋葬的量化.
- 估计地表水的生物基性生产情况.
主要成果:
- 修订后的净酸输入到海洋是每年6.1±2.0特拉莫尔的,主要来自河流 (150μM平均度).
- 生物基性二氧化对沉积物的净输出是每年7.1±1.8特拉莫尔的,平衡了输入.
- 生化生产总量为每年240±40特拉莫尔的,保存率为3%.
结论:
- 海洋的输入和输出处于近似的平衡中.
- 在海洋中的停留时间与生物吸收相比约为400年.
- 这项研究提供了海洋循环关键参数的最新数据.
相关概念视频
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Bulk or gross specific gravity is calculated by taking the ratio of the mass of aggregates in the saturated surface-dry state to the total volume that includes both the solids and the voids within the...
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Concrete in areas between tide marks, which undergo...
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Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the aggregate...
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the aggregate...
Bulk Density of Aggregate
Bulk density refers to the mass of aggregate particles that would fill a unit volume. The concept of bulk density originates from the inability to pack aggregate particles in a manner that completely eliminates void spaces. Hence, the term bulk refers to the volume that encompasses both the aggregates and the voids. This measurement is crucial when aggregates are batched by volume and is used to convert quantities by mass to volume.
Most natural mineral aggregates, like sand and gravel,...
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