Planting hedgerows: Biomass carbon sequestration and contribution towards net-zero targets.
Planting hedgerows: Biomass carbon sequestration and contribution towards net-zero targets.
复制标题
种植树篱：生物质碳固存和对净零目标的贡献。
DOI：
10.1016/j.scitotenv.2023.164482
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Biffi S
中科院分区：
文献类型：
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作者：
Biffi S
人们普遍鼓励种植树篱等农林业做法来缓解气候变化，迫切需要评估它们对国家“净零”目标的贡献。这项研究考察了以不同的比率种植树篱对英国未来40 年净零目标的影响，重点是2050年。通过对已知树龄的树篱进行破坏性取样，分析了当地树篱树种的碳含量，并测定了树篱地上生物量(AGB)C储量。AGB C蓄积量在最年轻的树篱中为8.34 mg C ha−1，在老树篱中为40.42 mg C ha−1。知道树篱的树龄，我们计算了它们的年平均AGB C固定速率，最高的是年轻的树篱(2.09 mg C ha−1yr−1)，最低的是39 龄的定期修剪的树篱(0.86 mg C ha−1yr−1)。我们给出了不同树龄层次间AGB C年固着率变化的时间序列，从造林后前6年的2.09 mg C ha−1yr−1增加到接下来的6 年的2.26 mg C ha−1yr−1，然后在13~40年间下降到0.43 mg C ha 1yr−1。我们的结果表明，如果广泛鼓励，绿篱种植可以成为一种有价值的大气二氧化碳捕获和储存工具，有助于实现净零目标。然而，目前的种植率(1778.8 Kmyr−1)太低，无法达到英国气候变化委员会设定的到2050年将树篱长度增加40 %的净零目标。到2050年，每年增加7148.1 公里的种植量将实现这一目标，并在40 年内将3.41TgCO2储存在绿篱AGB中，或10.13TgCO2储存在绿篱总生物量和土壤中，每年抵消英国年农业二氧化碳排放量的1.5%-4.5GCO2。
Agroforestry practices, such as hedgerow planting, are widely encouraged for climate change mitigation and there is an urgent need to assess their contribution to national ‘net-zero’ targets. This study examined the impact that planting hedgerows at different rates could make to UK net-zero goals over the next 40 years, with a focus on 2050. We analysed the carbon (C) content of native hedgerow species and determined hedge aboveground biomass (AGB) C stock via destructive sampling of hedges of known ages. AGB C stocks ranged from 8.34 Mg C ha−1in the youngest hedges, to 40.42 Mg C ha−1in old ones. Knowing the age of the hedgerows, we calculated their annual average AGB C sequestration rate, which was highest in young hedges (2.09 Mg C ha−1yr−1), and lowest in 39 year old mature, regularly trimmed hedgerows (0.86 Mg C ha−1yr−1). We present a time series of the annual AGB C sequestration rate change between hedge age categories, which increases from 2.09 Mg C ha−1yr−1in the first 6 years after planting, to 2.26 Mg C ha−1yr−1in the next 6 years, and then decreases to 0.43 Mg C ha−1yr−1between years 13 and 40. Our results indicate that, if encouraged widely, hedgerow planting can be a valuable tool for atmospheric CO2capture and storage, contributing towards net-zero targets. However, current planting rates (1778.8 km yr−1) are too low to reach the net-zero goal set by the UK Climate Change Committee of increasing hedgerow length by 40 % by 2050. An increased planting rate of 7148.1 km yr−1will achieve this goal by 2050, and, over 40 years, store 3.41 Tg CO2in hedge AGB, or 10.13 Tg CO2in hedge total biomass and in the soil, annually offsetting 1.5 %–4.5 % of UK annual agricultural CO2emissions.