在树树和本土的塞拉多植被中不同区间的碳储存
Fabiana Piontekowski Ribeiro1,2, Alcides Gatto2, Alexsandra Duarte de Oliveira1
1Embrapa Cerrados, BR-020, km 18, Planaltina 73310-970, DF, Brazil.
Plants (Basel, Switzerland)
|July 29, 2023
概括
树支架可以储存大量的碳,潜在地减轻二氧化碳排放. 然而,土地转型会影响碳动态,年轻的树可能会恢复土壤碳储量,而土壤碳储量会被农业所损失.
科学领域:
- 生态与环境科学 生态与环境科学
- 林业和农业科学 林业和农业科学
- 生物地质化学生物地质化学
背景情况:
- 了解不同生态系统中的碳 (C) 储存对于减缓气候变化战略至关重要.
- 树和Cerrado本地植被代表着不同的土地覆盖类型,具有不同的碳捕获潜力.
- 土地利用变化,特别是转向农业和随后的植树,显著影响土壤碳动态.
研究的目的:
- 为了评估和比较碳储存在各种隔间 (地面上方,根,土壤) 在树和本地Cerrado植被.
- 评估土地利用转型,特别是原生塞拉多到树种植园对碳库存和排放的影响.
- 调查树种植园在农业使用后恢复土壤碳的潜力.
主要方法:
- 通过森林库存测量 (DBH,Db,H) 和直接/间接立方体方法量化地面碳.
- 根碳用直接方法确定,使用圆形单体石到60厘米深度.
- 土壤碳库存的估计是从采集到100厘米深的样本中进行的,碳含量是使用CHNS元素分析仪分析的,气体排放是通过气体染色学分析的.
主要成果:
- 观察到总体高碳储量超过183.99Mg ha-1 ,可减少二氧化碳排放的潜力超过674.17Mg ha-1.
- 在所有评估区域都记录了低温室气体排放量 (<1 kg ha-1 yr-1),全球变暖潜力没有显著差异.
- 一个4岁的白树树显示出恢复土壤原始碳库存的潜力,而一个6岁的,以前在农业中,显示出土壤碳损失显著 (28.43 Mg ha-1).
结论:
- 树种植园可以有助于碳封存,但它们对土壤碳动态的影响高度依赖于先前的土地使用.
- 与直接转换为白树相比,将原生塞拉多转换为农业,然后再进行白树植林导致了土壤碳排放的大幅减少.
- 这些发现强调了在从小规模测量中升级碳捕获和排放估计时考虑景观转变和规模的重要性.
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