Organic fertilization promotes the accumulation of soil particulate organic carbon in a 9-year plantation experiment

10 páginas.- 5 figuras.- referencias

Management practices are expected to influence the capacity of forests to mitigate climate change. However, the long-term effects of afforestation on soil carbon accumulation in response to contrasting management regimes remain poorly understood. Here, we combined organic matter fractionation with a nine-year-long organic fertilization experiment to investigate the influences of largely accepted practices such as biochar (BC) and biogas-slurry (BS) inputs on the accumulation of soil particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) in three soil horizon depths (0–25, 25–50, and 50–75 cm, respectively). Our results suggested that both BS and BC significantly enhanced the POC and total soil organic carbon (SOC) content but overall did not significantly influence MAOC. Moreover, the POC and MAOC was more responsive to BS than BC. Further, our analyses revealed that the effects of BC on POC and MAOC were indirectly regulated by changes in the SOC: total nitrogen (TN) ratio, while BS influenced POC and MAOC by regulating TN. However, the responses of MAOC to the infiltration of organic fertilizers into the mineral soil should not be ignored, especially under high BC levels. Our work revealed that management practices are critical for supporting the long-term capacity of new forests to accumulate soil carbon, thereby facilitating the provision of nature-based solutions in response to climate change.

This study was supported by the National Key Research and Development Program of China (No. 2021YFD2200403, 2016YFD0600204),the National Natural Science Foundation of China (No. 32071594,32101339), and the key project of the open competition in JiangsuForestry (LYKJ[2022]01). Manuel Delgado-Baquerizo was supportedby a project from the Spanish Ministry of Science and Innovation(PID2020-115813RA-I00), and a project of the Fondo Europeo de Desarrollo Regional (FEDER), and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático“01—Refuerzo de la investigación, el desarrollo tecnológico y lainnovaci on”) associated with the research project P20_00879 (ANDABIOMA). Tingting Ren acknowledges the support of the Chinese Scholarship Council (CSC)

Peer reviewed