University of Nebraska-Lincoln, Lincoln, Nebraska, USA.
Colorado State University, Fort Collins, Colorado, USA.
Glob Chang Biol. 2024 Dec;30(12):e17604. doi: 10.1111/gcb.17604.
Anthropogenic activities have altered approximately two-thirds of the Earth's land surface. Urbanization, industrialization, agricultural expansion, and deforestation are increasingly impacting the terrestrial landscapes, leading to shifts of areas in artificial surface (i.e., humanmade), cropland, pasture, forest, and barren land. Land use patterns and associated greenhouse gas (GHG) emissions play a critical role in global climate change. Here we synthesized 29 years of global historical data and demonstrated how land use impacts global GHG emissions using structural equation modeling. We then obtained predictive estimates of future global GHG emissions using a deep learning model. Our results show that, from 1992 to 2020, the global terrestrial areas covered by artificial surface and cropland have expanded by 133% and 6% because of population growth and socioeconomic development, resulting in 4.0% and 3.8% of declines in pasture and forest areas, respectively. Land use was significantly associated with GHG emissions (p < 0.05). Artificial surface dominates global GHG emissions, followed by cropland, pasture, and barren land. The increase in artificial surfaces has driven up global GHG emissions through the increase in energy consumption. Conversely, improved agricultural management practices have contributed to mitigating agricultural GHG emissions. Forest, on the other hand, serves as a sink of GHG. In total, global GHG emissions increased from 31 to 46 GtCOeq from 1992 to 2020. Looking ahead, if current trends in global land use continue at the same rates, our model projects that global GHG emissions will reach 76 ± 8 GtCOeq in 2050. In contrast, reducing the rates of land use change by half could limit global GHG emissions to 60 ± 3 GtCOeq in 2050. Monitoring and analyzing these projections allow a better understanding of the potential impacts of various land use scenarios on global climate and planning for a sustainable future.
人为活动已经改变了地球表面的大约三分之二。城市化、工业化、农业扩张和森林砍伐正日益影响陆地景观，导致人工表面（即人为表面）、耕地、牧场、森林和荒地面积发生转移。土地利用模式和相关温室气体（GHG）排放对全球气候变化起着关键作用。在这里，我们综合了 29 年的全球历史数据，并通过结构方程模型展示了土地利用如何影响全球温室气体排放。然后，我们使用深度学习模型获得了对未来全球温室气体排放的预测估计。我们的研究结果表明，从 1992 年到 2020 年，由于人口增长和社会经济发展，全球人工表面和耕地面积分别增加了 133%和 6%，导致牧场和森林面积分别减少了 4.0%和 3.8%。土地利用与温室气体排放显著相关（p<0.05）。人工表面主导着全球温室气体排放，其次是耕地、牧场和荒地。人工表面的增加通过能源消耗的增加推动了全球温室气体排放的增加。相反，农业管理实践的改进有助于减少农业温室气体排放。森林则是温室气体的汇。总的来说，全球温室气体排放量从 1992 年的 31 增至 2020 年的 46 GtCOeq。展望未来，如果全球土地利用的当前趋势以相同的速度持续下去，我们的模型预测全球温室气体排放量将在 2050 年达到 76±8 GtCOeq。相比之下，将土地利用变化率降低一半可以将 2050 年的全球温室气体排放量限制在 60±3 GtCOeq。监测和分析这些预测可以更好地了解各种土地利用情景对全球气候的潜在影响，并为可持续的未来做好规划。
