4.2 Economic loss
China, the most populous nation, is a developing country and is still
overwhelmingly rural, yet aspires for fast modernization of the economy
(Smil, 1981). The
production
and construction activities can bring great economic benefits and value
in use for the country, so numerous productive and constructive
engineerings are undergoing. However, these projects are causing the
overdraft of natural resources and damage to the environment
(Du
et al., 2017). Also, Cheng et al. (2015) found anthropogenic water and
soil losses and huge economic losses caused by
productive
and constructive projects were more and more serious
recently.
In
1990, Chinese economic losses caused by soil and water
loss
totaled RMB 26.4
billion
Yuan, such as food loss, nutrition loss, falling crop yields, and cost
of Point-of-Use water purification (Jiang, 2007). Ren et al. (1997)
estimated that the economic losses caused by water and soil erosion were
RMB 49.5 billion
Yuan,
accounting for 6.5% of Chinese agricultural output value in the same
period.
Ministry of Water Resources of
PRC, Chinese Academy of Sciences and
Chinese
Academy of Engineering conducted the science review of soil and water
erosion and ecological safety in China, 2006. It was found that the
economic loss caused by soil erosion was 188.7 billion Yuan in 2000 –
the direct economic loss was RMB 64.26 billion Yuan and indirect
economic loss was RMB 124.44 billion Yuan, accounting for 2.1% of the
total GDP of the year (Jiang, 2007). Resource and environmental problems
have become a serious problem in the sustainable development of China.
Hence, the management of water and soil erosion is, naturally, of
critical importance for
China.
From the perspective of economics, neglecting the cost of natural
resources and the environment are the main reasons for
these
environmental problems. To put it bluntly, low investment and lack of
protection awareness caused by low investment are the cruces of soil and
water loss. Scientific estimation of investment in soil and water
conservation measures becomes the key.
Previously, the degree of soil erosion in all soil and water
conservation plans had never been evaluated and controlled
hierarchically, resulting in that investment of soil and water
conservation projects had not been determined hierarchically according
to different severity degree of soil erosion. All projects were carried
out following the same investment standard, leading to investments of
some projects were too high, and investments of other projects were
unable to control soil and water loss. Thus the degree of soil erosion
can be classified according to the amount of soil erosion calculated by
the universal soil loss equation (USLE) or its revised universal soil
loss equation (RUSLE) and the corresponding economic loss, because this
classification method is quite common and widely used in various fields,
for example, the classification of the landslide is mainly in accordance
with the amount of the landslides, the economic loss of landslides and
the death toll (MLRPRC, 2004). Then, a large number of projects are
carefully analyzed and summarized to calculate expenses per unit area
required for the projects of different grades, in turn, investments of
soil and water conservation measures required for different projects can
be calculated. Traditional one-size-fits-all computing investment for
all projects based on the same standard should be abandoned because the
projects that are built with investment calculated by traditional
methods still cause soil erosion at many cases even though the soil and
water conservation measures have been done, but it is not enough due to
low investment, as shown in Figure 4b. Of course, this is only the first
step of soil erosion control in productive and constructive projects,
and more experts, scholars, engineers, and managers are needed to
carefully summarize numerous projects in different regions to determine
more effective and reliable investments per unit area. Besides,
previously, all the water and soil conservation plans never calculate
economic loss as a quantitative index due to soil erosion, usually just
give a predicted amount of soil erosion. Actually, the predicted amount
of soil erosion has no direct effect on the investment by the
decision-makers, because policymakers are concerned about money more.
Until the amount of soil erosion is converted into money, policymakers
will have an intuitive understanding of the extent of soil loss. If the
economic losses of soil erosion are put into the soil and water
conservation plan, project earnings and economic loss will be easy to
compare, this will help decision-makers make decisions that help protect
the environment by increasing investment or improving awareness of
environmental protection and so on.
The economic loss caused by soil erosion can be calculated according to
the following components. The economic loss includes direct and indirect
economic loss. The direct economic loss includes sediment loss, nutrient
loss, water loss, while the indirect economic loss is divided into the
damage of water resource and ecological environment, and the decline of
productivity and
water-holding
capacity of land, etc. (Wang et al., 2011). Also, the cost of repairing
a damaged ecosystem caused by soil and water loss may be considered as
economic loss, such as the costs of soil and water conservation
measures. These detailed calculation examples can be found in the
literatures (Wang et al., 2011; Lv et al., 2012).