Storage of terrestrial carbon in boreal lake sediments and evasion to the atmosphere
Storage of terrestrial carbon in boreal lake sediments and evasion to the atmosphere
复制标题
DOI：
10.1029/96gb01666
复制
发表时间：
1996-09
影响因子：
5.2
通讯作者：
L. Molot;P. Dillon
中科院分区：
文献类型：
--
作者：
L. Molot;P. Dillon
对安大略省中部前寒武纪地盾上的 20 个小型森林流域和 7 个湖泊进行的 12 年碳质量平衡研究表明，研究湖泊中的大部分碳来自陆地来源，主要是泥炭地，而湖泊保留的碳（总输入量减去因湖泊流出而造成的损失）在湖泊沉积物和大气之间分配。滞留碳的分配是湖泊碱度的函数：逃逸碳/沉积物碳的比例随着碱度的降低而增加。这些碳通量关系应用于全球北方森林生物群落，以评估水生系统在生物群落内碳通量和库方面的作用。我们计算出，每年大约有 66 Tg 的有机和无机碳从北方森林生物群系输出到邻近的地表水域，其中 14 至 36 Tg 到达沿海水域。其余部分要么逃逸到大气中（12 至 21 Tg yr−1），要么储存在湖泊沉积物中（18 至 31 Tg yr−1）。北方湖泊沉积物中可能储存了大约 120 Pg 的碳，这是基于 5,000 年积累期的保守估计，其大小与最近对泥炭地 419 Pg 和植物生物量 64 Pg 的北方库估计相当。因此，由于湖泊沉积物中的储存，北方森林生物群落中储存的总碳量可能要大得多。
Carbon mass balance studies of 20 small, forested catchments and seven lakes on the Precambrian Shield in central Ontario during a 12-year period have shown that most carbon in the study lakes is derived from terrestrial sources, primarily peatlands, and that carbon retained by lakes (total inputs less loss via outflow from the lake) is partitioned between lake sediments and the atmosphere. The partitioning of retained carbon is a function of lake alkalinity: the ratio of evaded/sediment carbon increases with decreasing alkalinity. These carbon flux relationships were applied to the global boreal forest biome to evaluate the role of aquatic systems with respect to carbon fluxes and pools within the biome. We calculate that approximately 66 Tg of organic and inorganic carbon are exported annually from the boreal forest biome to adjacent surface waters of which 14 to 36 Tg reach coastal waters. The remainder is either evaded to the atmosphere (12 to 21 Tg yr−1) or stored in lake sediments (18 to 31 Tg yr−1). Approximately 120 Pg of carbon may be stored in boreal lake sediments, a conservative estimate based on an accumulation period of 5,000 years and a size comparable to recent boreal pool estimates of 419 Pg for peatlands and 64 Pg for plant biomass. Hence the amount of total carbon stored in the boreal forest biome may be significantly larger because of storage in lake sediments.