3.3 Meteoric Water Line (MWL)
The meteoric water lines (MWL) of
atmospheric precipitation in Xiamen city from 2018 to 2019, including
the total meteoric water line, typhoon precipitation meteoric water
line, normal precipitation meteoric water line and seasonal meteoric
water lines, were established based on the sample data collected during
the study period (Fig. 5). The slope of the total meteoric water line
(δD = 7.93δ18O + 1.77) in the study area is similar to
that of the Global Meteoric Water Line (GMWL, δD =
8δ18O + 10) (Dansgaard, 1964) and the Eastern China
Meteoric Water Line (CMWL, δD = 7.9δ18O + 8.2) (Zheng
et al., 1983), but the intercept distance is significantly smaller than
that of the two. The intercept of the typhoon-related precipitation
meteoric water line is also smaller than that of the GMWL and CMWL. In
addition, the intercept and slope of the seasonal meteoric water lines
are quite different. The slope was the highest in summer monsoon period
with 8.75, followed by seasonal shift period of 7.38, and the winter
monsoon period was the lowest with 6.30 and has the only negative
intercept of -3.58.
[Insert Figure 5]