Abstract Mitigating climate change is a critical challenge, and establishing agroforestry systems is identified as an effective strategy to increase carbon (C) sequestration in agricultural areas. However, the C storage potential of agroforestry systems, especially hedge agroforestry, still needs to be quantified in temperate areas. This study was performed in three mixed crop-livestock areas of western France and focused on hedges planted 20 years ago and on hedges inherited from the traditional hedge landscape and planted 40−120 years ago. We quantified soil organic carbon (SOC) stocks to a depth of 90 cm in 21 agricultural fields adjacent to a hedge, at 1, 3, 6 and 18 m from the hedge. Additional SOC storage by hedges were estimated in comparison to a reference plot, which corresponded to the 18-m measurement. SOC storage dynamics was empirically modeled from the measurements. SOC distribution by particle-size fraction at 0−30 cm depth was also measured. Compared to those in a reference plot, SOC concentrations and stocks were significantly higher in the adjacent field up to 1 m from the hedge at 0−60 cm depth, and up to 3 m from the hedge at 60−90 cm. However, 56–65 % of the additional SOC was stored at 0−30 cm depth and within 1 m of the hedge. Additional SOC stocks equaled 30−50 % of the C stored in non-harvested biomass. Estimates of SOC accumulation rates over 30 years after tree planting ranged from 0.034−0.096 Mg C yr−1 per 100 linear m of hedge. In the first 30 cm, 59–85 % of the additional SOC was stored in the labile particulate organic matter fraction. Our study demonstrated hedges’ significant potential to store SOC locally around themselves; combined with other practices to store C, they could help increase C storage potential at the scale of an agricultural landscape. Results also highlight the high variability in hedge storage potential, depending on hedge characteristics and intrinsic soil properties, whose underlying controlling processes remain to be understood.

中文翻译：

---

法国西部作物畜牧区树篱中的额外土壤有机碳储量

摘要 减缓气候变化是一项严峻的挑战，建立农林业系统被认为是增加农业地区碳 (C) 固存的有效策略。然而，温带地区的农林复合系统，尤其是树篱农林复合系统的碳储存潜力仍有待量化。这项研究是在法国西部的三个作物-畜牧混合区进行的，重点是 20 年前种植的树篱以及从传统树篱景观中继承并在 40-120 年前种植的树篱。我们在距树篱 1、3、6 和 18 m 处与树篱相邻的 21 个农田中量化了 90 cm 深度的土壤有机碳 (SOC) 储量。与对应于 18 米测量值的参考图相比，估计了树篱的额外 SOC 存储量。SOC 存储动态是根据测量经验建模的。还测量了 0-30 cm 深度处按粒径分数的 SOC 分布。与参考地块中的那些相比，在距树篱 0-60 cm 深度达 1 m 处，以及距树篱 60-90 cm 处达 3 m 的相邻田地中，SOC 浓度和储量显着更高。然而，56-65% 的额外 SOC 储存在 0-30 cm 深度和树篱 1 m 范围内。额外的 SOC 储量等于存储在非收获生物量中的碳的 30-50%。植树后 30 年 SOC 积累率的估计范围为每 100 米长的树篱 0.034-0.096 Mg C yr-1。在前 30 cm 中，59-85% 的额外 SOC 储存在不稳定的颗粒有机物部分中。我们的研究证明了树篱在本地存储 SOC 的巨大潜力；结合其他储存碳的做法，它们可以帮助增加农业景观规模的碳储存潜力。结果还突出了树篱存储潜力的高度可变性，这取决于树篱特征和内在土壤特性，其潜在控制过程仍有待了解。