Key Laboratory for Earth Surface Processes of the Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China.
Glob Chang Biol. 2014 Jul;20(7):2240-51. doi: 10.1111/gcb.12496. Epub 2014 May 2.
Scaling is central to ecology and Earth system sciences. However, the importance of scale (i.e. resolution and extent) for understanding carbon dynamics across scales is poorly understood and quantified. We simulated carbon dynamics under a wide range of combinations of resolution (nine spatial resolutions of 250 m, 500 m, 1 km, 2 km, 5 km, 10 km, 20 km, 50 km, and 100 km) and extent (57 geospatial extents ranging from 108 to 1 247 034 km(2) ) in the southeastern United States to explore the existence of scale dependence of the simulated regional carbon balance. Results clearly show the existence of a critical threshold resolution for estimating carbon sequestration within a given extent and an error limit. Furthermore, an invariant power law scaling relationship was found between the critical resolution and the spatial extent as the critical resolution is proportional to A(n) (n is a constant, and A is the extent). Scale criticality and the power law relationship might be driven by the power law probability distributions of land surface and ecological quantities including disturbances at landscape to regional scales. The current overwhelming practices without considering scale criticality might have largely contributed to difficulties in balancing carbon budgets at regional and global scales.
尺度在生态学和地球系统科学中至关重要。然而，对于理解跨尺度的碳动态，尺度（即分辨率和范围）的重要性尚未得到很好的理解和量化。我们模拟了美国东南部在广泛的分辨率（9 种空间分辨率为 250m、500m、1km、2km、5km、10km、20km、50km 和 100km）和范围（57 个地理空间范围从 108 到 1247034km²）的组合下的碳动态，以探索模拟区域碳平衡是否存在尺度依赖性。结果清楚地表明，在给定范围内估计碳封存存在一个临界分辨率阈值和误差极限。此外，还发现临界分辨率与空间范围之间存在不变的幂律缩放关系，因为临界分辨率与 A(n)（n 是常数，A 是范围）成正比。尺度临界性和幂律关系可能是由土地表面和生态数量的幂律概率分布驱动的，包括从景观到区域尺度的干扰。目前，由于没有考虑到尺度临界性，这种压倒性的做法可能在很大程度上导致了在区域和全球尺度上平衡碳预算的困难。
