Patterns of soil organic carbon, glomalin and structural stability in abandoned Mediterranean terraced lands
Patterns of soil organic carbon, glomalin and structural stability in abandoned Mediterranean terraced lands
复制标题
DOI：
10.1111/j.1365-2389.2012.01493.x
复制
发表时间：
2012-10-01
影响因子：
4.2
通讯作者：
Pardini, G.
中科院分区：
文献类型：
--
作者：
Emran, M.;Gispert, M.;Pardini, G.
土壤碳(C)储存潜力因其在减缓气候变化中的作用而备受关注，许多研究工作致力于研究土地利用变化(包括土地废弃)对碳动态的影响。对西班牙东北部耕地、森林土壤、灌木和牧场的土壤有机碳(SOC)、易提取的Bradford活性土壤蛋白(EE-BRSP)和Bradford活性土壤蛋白(BRSP)进行了每月间隔的比较分析。总体而言，在碳贮量较低的土壤中，EE-BRSP和BRSP的季节变化较大。在结构较好的土壤中，谷丙胺转化为更稳定的C型与较小的EE-BRSP/BRSP有关，而BRSP与有机碳有关，这表明对顽固的碳库和土壤结构都有积极的贡献。这种影响在8月份发现更多BRSP时似乎更加明显，这可能是因为高温和干燥的土壤中可能会发生甘露酚反应，以保存剩余的吸附水分，并在土壤微站点中提供更好的保护。两种团聚体(0.252.00和2.005.60 mm)中团聚体的结构稳定性(WSA)进一步增强了谷丙黄素的作用，表明其在团聚体和碳储存潜力方面具有良好的作用。在样带和废弃顺序上，土壤有机质含量和水分散失量均显著增加(P<；0.001)；两种团聚体的最大水分散失量在夏季普遍较大。然而，耕作土壤中的值始终小于灌丛和牧场下的土壤。同样，当土地利用从藤本植物转变为牧场时，碳库较小的土壤的二氧化碳-碳损失比例最大。因此，假定团聚体在防止有机碳矿化方面的作用，并强调了土地废弃后土壤监测的重要性。
Soil carbon (C) storage potential has received considerable attention for its role in climate change mitigation, and much research work has been devoted to studying the effect of land-use change, including land abandonment, on carbon dynamics. A comparative analysis of soil organic carbon (SOC), easily extractable Bradford-reactive soil protein (EE-BRSP) and Bradford-reactive soil protein (BRSP) was carried out at monthly intervals in a land-use sequence including cultivated soils, forest soils, shrubs and pasture in northeast Spain. In general, greater seasonal variations of both EE-BRSP and BRSP were found in soils with less carbon storage capacity. Turnover of glomalin into more stable C forms was associated with a small EE-BRSP:BRSP ratio in better structured soils and BRSP was related to organic carbon, suggesting positive contributions to both the recalcitrant carbon pool and soil structure. This effect seemed to be more pronounced in August when more BRSP was found, probably because of high temperature and dry soils in which glomalin may react to preserve residual adsorbed water and provide better protection in soil microsites. The role of glomalin was further enhanced by the structural stability of aggregates (WSA) investigated in two aggregate fractions (0.252.00 and 2.005.60 mm), indicating its beneficial effect in aggregation and carbon storage potential. BRSP, SOC and WSA increased significantly (P < 0.001) along the transect and abandonment sequence; the largest WSA values were generally greater in summer in both aggregate fractions. However, values in cultivated soils were always smaller than in soils under shrubs and pasture. Similarly, soils with a smaller carbon pool had the largest proportion of carbon loss as CO2-C when land use changes from vines to pasture. The role of aggregates in protecting organic carbon against mineralization was therefore postulated and highlighted the importance of soil monitoring after land abandonment.