College of Resources, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China.
Information and Educational Technology Center, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China.
Sci Total Environ. 2023 Jan 15;856(Pt 2):159227. doi: 10.1016/j.scitotenv.2022.159227. Epub 2022 Oct 5.
Strategies to increase carbon (C) sequestration in tea plantation soils are pertinent to mitigating global climate change, but little is known about the variation in C sequestration in soils planted with different tea varieties. In the current study, we collected 0-20 and 20-40 cm layer soil samples from a tea plantation planted with four tea varieties (Chuancha No.3 (CC3), Chuanmu No. 217 (CM217), Chuannong Huangyazao (CN), and C. sinensis 'Fuding Dabaicha' (FD)). Soil organic carbon (SOC) stock and composition in the bulk soil and aggregate fractions, as well as the SOC stability index (SI), were investigated. Both SOC stock and composition in the bulk soil or aggregate fractions were variable among the soils after planting different tea varieties. Overall, the highest SOC stock (0-40 cm) was observed in FD soil, followed by CN, CC3, and CM217 soil. This difference was dominated by the SOC stock associated with macroaggregates, and the highest macroaggregate-associated SOC stock was detected in FD soil in both soil layers. Moreover, FD soil showed the highest proportion of macroaggregates in both soil layers, accumulated the greatest recalcitrant organic carbon (ROC) and further contributed to the highest SI values of SOC associated with most aggregate fractions. In contrast, CN topsoil (0-20 cm) accumulated the greatest labile organic carbon (LOC) in most aggregate fractions, which had a positive correlation with the amount of C return by pruning litter. Ultimately, long-term planting of FD promoted macroaggregate formation, and ROC accumulation in aggregates greatly contributed to maintaining high C sequestration in the tea plantation soils and showed a high potential for future C budgets; in contrast, the tea plantation soil planted with CN could be a potential C source because of high C return.
增加茶园土壤碳（C）固存的策略与缓解全球气候变化有关，但对于不同茶树品种种植的土壤中 C 固存的变化知之甚少。在本研究中，我们从种植了四个茶树品种（川茶 3 号（CC3）、川牧 217 号（CM217）、传农黄芽早（CN）和福鼎大白茶（FD））的茶园中采集了 0-20 和 20-40 cm 层土壤样品。研究了原状土和团聚体中土壤有机碳（SOC）储量和组成以及 SOC 稳定性指数（SI）。种植不同茶树品种后，原状土和团聚体中 SOC 储量和组成均存在差异。总体而言，FD 土壤的 SOC 储量（0-40 cm）最高，其次是 CN、CC3 和 CM217 土壤。这种差异主要由与大团聚体相关的 SOC 储量决定，在两个土层中，FD 土壤中大团聚体相关的 SOC 储量最高。此外，FD 土壤在两个土层中大团聚体的比例最高，积累了最大的难降解有机碳（ROC），并进一步导致与大多数团聚体相关的 SOC 的 SI 值最高。相比之下，CN 表土（0-20 cm）在大多数团聚体中积累了最大的易降解有机碳（LOC），这与修剪凋落物的 C 归还量呈正相关。最终，FD 的长期种植促进了大团聚体的形成，以及 ROC 在团聚体中的积累，这极大地有助于维持茶园土壤中的高 C 固存，并显示出对未来 C 预算的高潜力；相比之下，种植 CN 的茶园土壤可能是一个潜在的 C 源，因为 C 归还量高。
