2.4 Data analysis
The wind erosion material in the wind tunnel mainly moved horizontally.
Thus, the amount of wind erosion and particulate matter emissions can be
expressed in a unified horizontal direction (Panebianco et al., 2016).
Affected by the BSC coverage, the amount of wind erosion produced in
this research was relatively small. Thus, a high-precision electronic
scale was used to measure wind erosion. The total amount of wind erosion
was expressed as the difference in weight between the undisturbed soil
collection box before and after the test. To calculate the proportion of
particulate matter emissions in the total wind erosion, the particulate
matter concentration was converted to the particulate matter mass,
according to the specifications of the wind tunnel, using the following
formula:
\begin{equation}
m=\frac{C\times v\times t\times 0.6\times 0.8}{1000000}\nonumber \\
\end{equation}where m is the mass of particulate matter (in grams); C is
the emission concentration of particulate matter
(μg/m3); v is the wind speed (m/s); t is
the blowing time (s); and 0.6 and 0.8 are the height and width at the
middle of the wind tunnel (m), respectively.
In order to consider the
importance of the influencing factors, this study carried out a linear
regression fitting for wind speed, coverage, wind erosion and
particulate emissions, and standardized the coefficients as follows:
\begin{equation}
B_{i}=b_{i}\times\frac{S_{i}}{S_{j}}\nonumber \\
\end{equation}where B is the standardization coefficient; b is the
unstandardized coefficient; S is the standard deviation; iis the independent variable; and j is the dependent variable.
The linear fitting and coefficient standardization methods used in this
study were completed with SPSS 25. Data analysis was completed with
Microsoft Excel 2019 and the drawing using Sigmaplot 12.5.