Soil carbon storage along a 46-year revegetation chronosequence in a desert area of northern China
Soil carbon storage along a 46-year revegetation chronosequence in a desert area of northern China
复制标题
中国北方沙漠地区46年植被恢复时序的土壤碳储量
DOI：
10.1016/j.geoderma.2018.03.024
复制
发表时间：
2018-09-01
期刊：
影响因子：
6.1
通讯作者：
Zhang, Ding-Hai
中科院分区：
文献类型：
--
作者：
Chen, Yong-Le;Zhang, Zhi-Shan;Zhang, Ding-Hai
土壤含有大部分陆地碳；然而，大多数研究只关注土壤1米甚至更浅土层的有机碳（SOC），而土壤无机碳（SIC）和根系碳（RDC）往往被忽视。在此基础上，研究了移动沙丘46年植被恢复过程中0 ~ 3.0 m深度土壤碳的分布特征，并评价了土壤含水量对土壤碳的潜在影响。土壤有机碳密度沿0 ~ 3.0 m剖面显著增加，且在0 ~ 0.4 m浅层的增加速度快于0.4 m以下深层。碳化硅密度虽然没有显著增加，但占土壤碳总量的65%左右，占深层至少82%。在时间序列上，浅层和深层的活RDC和死RDC均显著增加。RDC占土壤总碳的比例较小，平均为3.19%。SOC与浅层和深层的活RDC密切相关。土壤含水量与土壤有机碳仅在浅层呈显著正相关。浅层有机碳储量达到自然植被立地水平需要57.4 a，而深层有机碳储量达到自然植被立地水平需要100 a。结果表明，植被恢复后，土壤碳积累在浅层和深层都是一个缓慢的过程，土壤碳的增加以有机碳为主。因此，在水资源有限的生态系统中，植被恢复对土壤碳的影响应考虑有机碳、SIC和RDC。
Soil contains the majority of terrestrial carbon; however, most studies only focus on soil organic carbon (SOC) in the first meter or even shallower layers, and soil inorganic carbon (SIC) and root-derived carbon (RDC) are often overlooked. Here, we investigated the distribution of soil carbon at a depth of 0-3.0 m over a 46-year revegetation chronosequence on moving sand dunes and evaluated the potential influence of soil water content on soil carbon. The SOC density increased significantly along the 0-3.0 m profile, and showed a faster increasing rate in shallow layer (0-0.4 m) than that of the deep layers below 0.4 m. Although the SIC density did not increase significantly, it accounted for > 65% of the total soil carbon in shallow layer and at least 82% in deep layer. The live and dead RDC increased significantly over the chronosequence in both shallow and deep layers. The RDC accounted for a small amount of the total soil carbon at an average of 3.19%. The SOC was closely linked with live RDC in both the shallow and deep layers. The soil water content was only positively correlated with the SOC in the shallow layer. The SOC storage in the shallow layer required 57.4 years to reach the level at the natural vegetation site, whereas the storage in the deep layers required > 100 years. Our results indicated that soil carbon accumulation is a slow process in both shallow and deep layers after revegetation, and the most notable increase in soil carbon was accounted by SOC. We suggest that SOC, SIC and RDC should be considered when assessing the effects of revegetation on soil carbon in water-limited ecosystems.