1 | INTRODUCTION
China has long been suffering from serious soil erosion. The
environmental problems caused by soil erosion, i.e. land degradation and
the loss of land resources, have become more serious, which have
seriously threatened food security, biodiversity, water resources
safety, and human living environment in China (Li & Fang, 2016). Soil
erosion caused by natural factors is widely distributed on all the earth
surfaces, so numerous studies focus on the soil erosion problems caused
by natural factors, e.g. rainfall (Xu et al., 2020), topography slope
(Li et al., 2020), wind (Wang & shao, 2013), vegetation cover (Zhou,
2008), freeze-thaw (Wu et al., 2018).
However, as everyone knows, soil erosion is strongly influenced by not
only natural factors but also unreasonable human activities. It is
estimated that nearly 60% of present soil erosions are induced by human
activity (Yang et al., 2003). Currently, China faces economic
development, numerous productive and constructive engineerings as one
kind of severe human activity are being conducted.
Jiang (2007) found that the total
number of productive and constructive engineering was 7.68 ×
104, the total area was 552.8 × 104hm2 in China from 2001 to 2005. However, productive
and constructive engineering involves extensive land disturbance, which
results in the removal of vegetation, mass wasting along the cut slopes,
runoff over bare areas formed by excavation, unconsolidated deposition,
and reshaping of the topography (Li et al., 2014).
Such
activities directly cause soil erosion and land degradation. For
example, Jiang (2007) pointed out that the total amount of abandoned
soil and slag was about 92.1× 108 t, and the total
amount of soil erosion was 9.5× 108 t in China from
2001 to 2005. Also, Zhang et al. (2006) estimated that
the area of land degradation caused
by productive and constructive engineering accounted for 66% of the
total area of land degradation and about 60% of land occupied by
productive and constructive engineering was farmland.
The
loss of land resources caused by that farmland is converted into
construction land in China indirectly results in that a large amount of
ecological land is reclaimed as farmland. So, productive and
constructive engineering has brought serious land degradation, loss of
land resources and loss of ecological land along with soil erosion.
However, these environmental issues caused by productive and
constructive engineering in China have not gained enough attention. Only
a few studies of soil erosion caused by mining (Sinha et al., 2017) and
road (Dong et al., 2012) projects are available. Therefore, this article
focuses on the problem of soil erosion and related environmental issues
caused by productive and constructive engineering, and specifically
selects clean energy projects, such as photovoltaics and wind energy,
across China as case studies. Because clean energy emits fewer
greenhouse gases and is more environmentally friendly than traditional
energy projects such as petroleum, natural gas, and coal, clean energy
will be the trend of future energy supply. At the same time, it also
causes many man-made environmental problems like other construction
projects, which can provide a reference for the construction projects of
other industries.
Here, the authors have conducted field investigations and statistical
analysis of clean energy projects in China for years, which have been
used to understand the reasons causing these environmental issues. In
turn, some comprehensive policy suggestions are proposed to enhance the
awareness of protecting environments in the process of constructive
engineering and to control these issues. And, the conclusions and policy
recommendations of this article will provide reference and guidance for
clean energy projects construction in the future and even other
large-scale productive and constructive projects in China or other
countries.