College of Land Management, Nanjing Agricultural University, Nanjing 210095, China; Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen 1958, Denmark; China Resources & Environment and Development Academy, Nanjing, 210095, China.
College of Land Management, Nanjing Agricultural University, Nanjing 210095, China; State and Local Joint Engineering Research Center of Rural Land Resources Utilization and Consolidation, Nanjing, 210095, China; China Resources & Environment and Development Academy, Nanjing, 210095, China.
J Environ Manage. 2022 Nov 15;322:116032. doi: 10.1016/j.jenvman.2022.116032. Epub 2022 Aug 27.
Although compact urban form plays an important role in constraining emissions of carbon dioxide (CO), the boundary for the impact of compact urban form on these emissions has nevertheless received little attention. We consequently applied the entropy weight method and several key landscape metrics to a dataset from 295 cities in China to quantify urban form compactness (UFC) between 2000 and 2015. The STIRPAT model then was employed to estimate the impact of UFC on CO emissions, and a panel threshold regression model was used to estimate threshold effects capable of limiting the impact of compact urban form on emissions. Although CO emissions increased sharply over the 15-year study period, a significant negative relationship between UFC and CO emissions was detected. Two thresholds of UFC were detected, and this allowed three categories to be differentiated: before the first threshold, between the two thresholds, and after the second threshold. These categories were respectively associated with no impact, strong impact, and weak impact of UFC on reduction of carbon emissions in the 295 cities. Carbon emissions reduction consequently becomes effective when the UFC exceeds the first threshold and effectiveness persists but at a reduced level when the UFC exceeds the second threshold. Further temporal analysis confirmed that an increasing number of mostly small- and medium-sized cities could constrain their future carbon emissions by adopting a compact urban form. Thus, government policies should emphasize UFC as a strategy to reduce CO emissions. Moreover, by defining the range of compact urban form that has the greatest impact on CO emissions, our study deepens the overall understanding of the influence of UFC on carbon emission reductions, so as to make contributions to the design of low-carbon cities.
尽管紧凑的城市形态在限制二氧化碳（CO）排放方面发挥着重要作用，但紧凑城市形态对这些排放的影响边界却很少受到关注。因此，我们应用熵权法和几个关键的景观指标，对来自中国 295 个城市的数据集进行了分析，以量化 2000 年至 2015 年期间的城市形态紧凑度（UFC）。然后，我们采用 STIRPAT 模型来估计 UFC 对 CO 排放的影响，并采用面板门槛回归模型来估计能够限制紧凑城市形态对排放影响的门槛效应。虽然在 15 年的研究期间 CO 排放量急剧增加，但我们发现 UFC 与 CO 排放量之间存在显著的负相关关系。我们检测到了两个 UFC 门槛值，并将其分为三个类别：第一个门槛值之前、两个门槛值之间以及第二个门槛值之后。这三个类别分别与 295 个城市中 UFC 对碳排放减少的无影响、强影响和弱影响相关。当 UFC 超过第一个门槛值时，碳排放减少变得有效，并且当 UFC 超过第二个门槛值时，有效性仍然存在，但降低。进一步的时间分析证实，越来越多的中小城市可以通过采用紧凑的城市形态来限制未来的碳排放。因此，政府政策应强调 UFC 作为减少 CO 排放的策略。此外，通过定义对 CO 排放减少影响最大的紧凑城市形态范围，我们的研究深化了对 UFC 对碳排放减少影响的整体理解，为低碳城市的设计做出了贡献。
