## 3 Results
### Temporal Distributions of Carbon Fluxes for the Selected Major Land Uses
#### 3.4.2 Temporal Distributions of NEE  
Developed land-use of the ET climate zone showed higher monthly carbon emission and uptake compared to the SC climate zone (Figure 10f). Both climate zones had carbon emissions during the late fall and spring (November-April) and carbon uptakes during the summer and early fall (May-September). However, both climate zones had the highest carbon emissions and uptakes in a different month each year. For example, in 2015, ET and SC climate zones had the highest carbon emission, respectively, in April and March, whereas the highest carbon uptake was, respectively, in July and October/December (two peaks). Both climate zones showed slightly different median, and mean NEE (Figure 11b). However, the ET climate zone had larger NEE range than the SC climate zone. Additionally, NEE of developed land in the ET and SC climate zones showed slightly better correlations in 2016 and 2017 than in 2015 and 2018 (Table 4). Forestland of the ET and TP climate zones showed the highest carbon uptake, respectively, in July 2015 and August 2017 (Figure 10g). Forestland of the ET climate zone had higher carbon uptake every year than the TP climate zone except in 2017. In August 2017, the TP climate zone had NEE of \(-\)71.4 g C m\({}^{-2}\) mo\({}^{-1}\) and the ET climate zone had NEE of \(-\)51.7 g C m\({}^{-2}\) mo\({}^{-1}\). While forestlands of ET and TP climate zones showed some similarity in the temporal distribution of NEE (highest carbon uptake during summer in both zones), TP had very low carbon emission every year (0.4 to 1.4 g C m\({}^{-2}\) mo\({}^{-1}\)) except in May 2017, when this zone had NEE of 22.4 g C m\({}^{-2}\) mo\({}^{-1}\). Forestland of the TP climate zone had a smaller NEE range than forestland in the ET climate zone (Figure 11b). In comparison, mean, and range of NEE in TP climate zone were significantly different than the ET climate zone. The NEE median was close to each in both climate zones. R\({}^{2}\) values of 0.81 and 0.53 and \(p\)-values of 0.0009 and 0.0071 in 2015 and 2016 for NEE for forestland in two climate zones showed very good correlations, and R\({}^{2}\) values of 0.17 and 0.03, and \(p\)-values of 0.1813 and 0.5779 in 2017 and 2018 for NEE for forestland in two climate zones showed poor correlations (Table 4). Shrublands of EP and TP climate zones showed similar seasonal variations in carbon emission and uptake during the study period (Figure 10h). However, the EP climate zone dominated by shrubland had slightly higher carbon emission than the TP climate zone. Similarly, it had a slightly higher carbon uptake than the TP climate zone in 2015-2016 and lower in 2017-2018. The ET climate zone had the highest carbon emission (18.3 g C m\({}^{-2}\) mo\({}^{-1}\)) in March 2018, and the TP climate zone had the highest carbon emission (12.6 g C m\({}^{-2}\) mo\({}^{-1}\)) in May 2018. On the other hand, the highest carbon uptake in EP (\(-\)43.3 g C m\({}^{-2}\) mo\({}^{-1}\)) and TP (\(-\)32.4 g C m\({}^{-2}\) mo\({}^{-1}\)) climate zones were observed in April 2015. R\({}^{2}\) values and \(p\)-values (0.93 to 0.61 and \(<\)0.0001 to 0.0027) showed very good correlations for NEE for shrubland in EP and TP climate zones each year except in 2017, when R\({}^{2}\) value and p-value were 0.20 and 0.1435 (Table 4). Both zones showed similar means and medians of NEE. However, the shrubland at the EP climate zone showed larger NEE range than the TP climate zone (Figure 11b). Cropland of both climate zones showed higher carbon uptakes and emissions, respectively, during the summer and winter. However, cropland of the UC climate zone had more than double carbon emission and uptake during the peak of the year. For example, in 2015, the UC climate zone had the highest carbon uptake (\(-\)130.5 g C m\({}^{-2}\) mo\({}^{-1}\)) in July, whereas the HP climate zone had the highest carbon uptake (\(-\)52 g C m\({}^{-2}\) mo\({}^{-1}\)) in August (Figure 10i).