Global carbon sequestration in tidal, saline wetland soils
Global carbon sequestration in tidal, saline wetland soils
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DOI：
10.1029/2002gb001917
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发表时间：
2003-12-10
影响因子：
5.2
通讯作者：
Lynch, JC
中科院分区：
文献类型：
--
作者：
Chmura, GL;Anisfeld, SC;Lynch, JC
[1]湿地是陆地生物碳库的最大组成部分，因此在全球碳循环中发挥着重要作用。然而，大多数全球碳预算都集中在大面积的旱地生态系统上，而没有考虑到许多小型、分散的碳储存生态系统，如潮汐盐碱湿地。我们收集了154个地点的数据，这些地点位于大西洋和太平洋海岸的西部和东部，以及印度洋、地中海和墨西哥湾的红树林和盐沼。这些地点的纬度范围从印度洋的南纬22.4度到东北大西洋的北纬55.5度。红树林沼泽的平均土壤碳密度（0.055 +/- 0.004 g cm（-3））显著高于盐沼的平均值（0.039 +/- 0.003 g cm（-3））。红树林沼泽和大米草沼泽的土壤碳密度随着年平均温度的升高而下降，这可能是由于在较高温度下腐烂速率增加。相反，红树林沼泽和盐沼的固碳率没有显著差异。沼泽内沉积物积累率的变化是碳固存率的主要控制因素，掩盖了与气候参数的任何关系。在全球范围内，这些组合的湿地存储至少44.6 Tg C yr（-1），可能更多，因为详细的区域库存没有在中国和南美洲的盐沼。淡水湿地，特别是北方泥炭地作为碳汇的作用受到了广泛关注。与泥炭地相比，盐沼和红树林释放的温室气体可以忽略不计，单位面积储存的碳更多。
[1] Wetlands represent the largest component of the terrestrial biological carbon pool and thus play an important role in global carbon cycles. Most global carbon budgets, however, have focused on dry land ecosystems that extend over large areas and have not accounted for the many small, scattered carbon-storing ecosystems such as tidal saline wetlands. We compiled data for 154 sites in mangroves and salt marshes from the western and eastern Atlantic and Pacific coasts, as well as the Indian Ocean, Mediterranean Ocean, and Gulf of Mexico. The set of sites spans a latitudinal range from 22.4degreesS in the Indian Ocean to 55.5degrees N in the northeastern Atlantic. The average soil carbon density of mangrove swamps (0.055 +/- 0.004 g cm(-3)) is significantly higher than the salt marsh average (0.039 +/- 0.003 g cm(-3)). Soil carbon density in mangrove swamps and Spartina patens marshes declines with increasing average annual temperature, probably due to increased decay rates at higher temperatures. In contrast, carbon sequestration rates were not significantly different between mangrove swamps and salt marshes. Variability in sediment accumulation rates within marshes is a major control of carbon sequestration rates masking any relationship with climatic parameters. Globally, these combined wetlands store at least 44.6 Tg C yr(-1) and probably more, as detailed areal inventories are not available for salt marshes in China and South America. Much attention has been given to the role of freshwater wetlands, particularly northern peatlands, as carbon sinks. In contrast to peatlands, salt marshes and mangroves release negligible amounts of greenhouse gases and store more carbon per unit area.