Page 102 - JCAU-5-2

Journal of Chinese
Architecture and Urbanism Study on ecosystem service value in Wuhan

substances, such as SO , NO , HF and dust. The paper (B) Flood regulation
x
2
mainly considers the functions of SO and dust reduction The main function of flood regulation is to store and
2
(Fang et al., 2011; Bai et al., 2010; Bai et al., 2011). The release excess water slowly, and redistributes water in
formula is as follows: time and space to avoid and reduce flood disasters. The
alternative project method was adopted in this study
V = Q × P +Q × P d (VI) (Dai et al., 2021; Li et al., 2018; Ida et al., 2013; Deng
S
pe
d
S
Where V is the value of environmental purification; et al., 2019; Zhang et al., 2017), and the formula is:
pe
Q is the annual SO absorption (kg); Q is the annual V = Q × P (VIII)
S
d
2
r
dust reduction (t); P is the investment cost per unit SO fr Where V is the flood regulation value; Q is the flood
S
2
reduction (yuan/kg); and P is the investment cost per unit regulation volume (m /a); and P is the reservoir cost per
fr
3
d
dust reduction (yuan/t). r
unit storage capacity (yuan/t).
Based on other research achievements (Xiao et al., 2009; According to relevant research (Chen & Zhang, 2021;
Bai et al., 2011), the annual SO absorption and the annual Pan et al., 2018), the flood storage capacity is calculated
2
dust reduction can be adopted. The annual dust reduction based on the unit area flood storage capacity and maximum
and the investment cost per unit dust reduction are from submergence depth of the relevant land types. The reservoir
the Standards and Calculation Methods for Collecting cost per unit storage capacity is the same as above.
Pollution Discharge Fees in China.
2.4.7. Soil retention
2.4.6. Hydrological regulation
Soil retention deals with the impact of nature on vegetation
The natural ecosystem plays an important role in cover and root system, which stabilize the soil and intercept
water conservation and flood regulation by adjusting the rainfalls to prevent the erosion of soil. Soil retention is
hydrological paths. mainly reflected in reducing soil erosion, maintaining soil
(A) Water conservation fertility, and reducing sediment deposition in rivers and
The services derived from water conservation relate to lakes.
the regular distribution of hydrological flows at the earth’s (A) Prevention of soil erosion
surface, which is manifested in the functions of vegetation According to the difference between potential and
interception of precipitation, enhancement of soil actual erosion modulus (Zhang et al., 2016; Han et al.,
infiltration, mitigation of surface runoff, and so on. The 2021; Ouyang et al., 1999), the value of soil erosion
value of water conservation can be determined according reduction is calculated as follows:
to the storage cost of the reservoir project (alternative V = A × P × (X − X )/ρ (IX)
project method) (Tang et al., 2016; Zhang et al., 2016). se et 2 1
Where V is the annual reduced soil erosion value; A
se
V = A × (P−E) × P r (VII) is the ecosystem area (hm ); P is the cost of earthwork
2
wc
et
3
Where V is the value of water conservation; A is the excavation and transportation per unit volume (yuan/m );
wc
2
ecosystem area (hm ); P is the annual precipitation (mm); X is the potential erosion modulus (t/hm ·a); and X is the
2
1
2
2
E is the average evapotranspiration (mm/a); and P is the actual erosion modulus (t/hm ·a); and ρ is the soil bulk
r
3
cost of reservoir per unit storage capacity (yuan/t). density (g/cm ).
According to Wuhan Water Affairs Bureau and According to the consumption quota of relevant
Wuhan Lake Bureau, the average annual precipitation in engineering projects in Hubei province (“Hubei Provincial
Wuhan in 1996, 2000, 2005, 2010, 2015, and 2018 year Construction Engineering,” 2008, 2018), the cost of
was 1166.00 mm, 1051.81 mm, 1096.1 mm, 1494.8 mm, earthwork excavation and transportation per unit volume
1391.6 mm, and 1304.3 mm, respectively. The runoff could be obtained. The potential erosion modulus and
coefficients of different types of land are derived from the the actual erosion modulus were obtained from relevant
the “Guidelines for Planning and Design of Sponge Cities research (Han et al., 2021; Ouyang et al., 1999). The soil
in Wuhan” (Wuhan Water Bureau, 2015). In the 1990s, bulk density in Wuhan was taken as the average value of
3
the unit cost for a reservoir was 2.17 yuan/t (Bai et al., 1.35 g/cm (Wang et al., 2020).
2011), and has been revised to as 2.74 yuan/t, 6.11 yuan/t, (B) Maintenance of soil fertility
7.28 yuan/t, 8.44 yuan/t, and 8.80 yuan/t according to the The value of maintaining soil fertility can be
price increase index in 2000, 2005, 2010, 2015, and 2018, expressed by the market value of chemical fertilizer
respectively (Wuhan Statistical Bureau, 1997; 2001; 2006; with the same fertility in soil (Ye et al., 2013; Miu
2011; 2016; 2019). et al., 2016; Wang et al., 2013; Chen & Zheng, 2021;
Volume 5 Issue 2 (2023) 7 https://doi.org/10.36922/jcau.0427