Iron-bound organic carbon dynamics in peatland profiles:The preservation equivalence of deep and surface soil

More than half of the carbon pools in peatlands are stored in the soil layers below 30 cm,yet little is known about the carbon stabilizing factors at these depths.Although iron oxide minerals are considered to be important for stabilizing organic carbon(OC),their role in the preservation of OC in peatlands,especially in the deep layers,is poorly understood.Here,we collected 1 m soil profiles from six peatlands in Central and West China to quantitatively study the vertical distribution characteristics of iron-bound OC(Fe-bound OC),and the influencing physicochemical properties of the soil.The results showed that the content of reactive iron(FeR)was enriched in the top layer and decreased gradually with depth.While Fe-bound OC was positively correlated with FeR,its concentration did not decrease with depth in the peat profile.There were no obvious trends in the distributions of FeR and Fe-bound OC with water level fluctuations in the peat profile.In addition,the proportion of Fe-bound OC to soil organic carbon in the deep peat(31 to 100 cm)was equivalent to that in the surface peat(0 to 30 cm),indicating that iron oxide mineral provides comparable protection of OC in both layers.According to upper estimates of global peatland carbon storage(612 Pg),it could be predicted that 23.81±11.75 Pg of OC is protected by association with FeR.These results indicated that iron oxide minerals are the effective"rusty sink"of OC sequestration in peatland,and a key factor for its long-term preservation.The results from this study make a valuable contribution to the carbon dynamics knowledgebase for peatlands,and provide a basis for improved predictive simulations.

Qinghai-tibetan plateau peatland sustainable utilization under anthropogenic disturbances and climate change

Often referred to as the“Third Pole,”China’s Qinghai-Tibetan Plateau developed large amounts of peatland owing to its unique alpine environment.As a renewable resource,peat helps to regulate the climate as well as performing other important functions.However,in recent years,intensifying climate change and anthropogenic disturbances have resulted in peatland degradation and consequently made sustainable development of peatland more difficult.This review summarizes peatland ecological and economic functions,including carbon sequestration,biodiversity conservation,energy supplies,and ecotourism.It identifies climate change and anthropogenic disturbances as the two key factors attributing to peatland degradation and ecosystem carbon loss.Current problems in environmental degradation and future challenges in peatland management under the effects of global warming are also discussed and highlighted.

“C-wetland”:A new paradigm to enhance conservation of carbon-rich wetlands

Wetlands have the highest ecosystem service value among all terrestrial eco-systems.Among their ecosystem services,carbon sequestration and its potential ability to mitigate climate change have been extensively discussed recently,not only in the academic community but in media during COP27 of UNFCCC and COP14 of Ramsar.In particular,peatlands-peat-accumulating wetlands-accumulate 600 Gt C globally.