Climatology and Environmental Meteorology, Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany.
Climatology and Environmental Meteorology, Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany.
Sci Total Environ. 2017 Dec 31;607-608:623-632. doi: 10.1016/j.scitotenv.2017.07.052. Epub 2017 Jul 27.
The CO surface-atmosphere exchange of an unirrigated, extensive green roof in Berlin, Germany was measured by means of the eddy covariance method over a full annual cycle. The present analysis focusses on the cumulative green roof net ecosystem exchange of CO (NEE), on its seasonal variation and on green roof physiological characteristics by applying a canopy (A-g) model. The green roof was a carbon sink with an annual cumulative NEE of -313gCOmyear, equivalent to -85gCmyear. Three established CO flux gap-filling methods were applied to estimate NEE and to study the performance during different meteorological situations. A best estimate NEE time series was established, which chooses the gap filling method with the highest performance. During dry periods daytime carbon uptake was shown to decline linearly with substrate moisture below a threshold of 0.05mm, whereas night-time respiration was unaffected by substrate moisture variation. The roof turned into a temporary C source during dry conditions in summer 2015. We conclude that the carbon uptake of the present green roof can be optimized when substrate moisture is kept above 0.05mm.
德国柏林未灌溉的大面积绿色屋顶的 CO 表面-大气交换通过涡度相关法在整个年度周期内进行了测量。本分析集中于 CO 的绿色屋顶净生态系统交换的累积量（NEE）、季节性变化以及应用冠层（A-g）模型的绿色屋顶生理特性。绿色屋顶是一个碳汇，年累积 NEE 为-313gCOmyear，相当于-85gCmyear。应用了三种已建立的 CO 通量间隙填充方法来估算 NEE，并研究不同气象条件下的性能。建立了最佳估计 NEE 时间序列，该序列选择性能最高的间隙填充方法。在干燥时期，白天的碳吸收随着基质水分低于 0.05mm 的阈值呈线性下降，而夜间呼吸不受基质水分变化的影响。2015 年夏季干燥条件下，屋顶变成了一个临时的 C 源。我们得出结论，当基质水分保持在 0.05mm 以上时，可以优化当前绿色屋顶的碳吸收。
