] area of forest
ced changes in
1.3%. The rest
between other
trajectory of F-
6%. Cropland
al area of the
ear-cutting and
to unused land,
ed area. About
lost to built-up
| change is 1.7
rea during past
ION
generally have
nd land cover
offer statistical
rowth drives or
d Barnes 1985).
" the study area
3 million. The
for grain have
the study areas
ipid economic
changes in this
f the Yanbian
; a boost in
struction. The
oincided with a
ic of China, in
ic construction
of forestry in
Yu et al. 2011).
ed for a long
ywned forestry
ountains. Since
rest protection,
a combination
jn. However, in
the broadening
and neglected
rly exhausted
t al 2000). The
ngest influence
1949(Gao et al.
ast China was
as a continuous
)1, which could
plands on steep
id. Since 2002,
driven by the
ited land.
ltivated land to
est Conversion
an Ecological
he nation since
st China have
Is have slowly
increased (Wang et al. 2004). To stimulate motivation for forest
protection efforts, the central government has started to pay
ecological subsidies to the local foresters whose forests were
classified as ecological welfare forests under complete
protection since 2003 (Dai et al. 2009). Some forested area was
rehabilitated in Yanbian prefecture. Nevertheless, the
afforestation area decreased from 48.9x10° ha to 6.7x10? ha for
the period of 1999-2006. The cultivated land in state-owned
forestry enterprises is mostly used for growing economic crops
such as ginseng and orchards (Zhao et al.2011). The continuous
shrinkage and fragmentation of forests requires more effective
efforts towards forest protection in the study area.
In short, the area of forestland decreased 4% in the past 20
years. The quality of forest has severely worsened, and
considerable decrease in forest was mainly attributed to
reduction of closed forest. The patch numbers of forests
increased while the average area decreased. Fractal dimension
analysis showed that forest patch shape tended to be regular and
simpler indicating more human influence. Forests experienced
the process of substantial clearing and fragmentation. The
representative temporal trajectories of forest change were
driven by human activities including cultivation, logging,
reforestation and urban construction. The transformation from
forests to croplands is a result of pressure to supply more food
and more economic income for the rapidly increasing
population and to meet economic demand. The study implies
that increased human pressures and socioeconomic
development play an important role in the shrinkage and
degradation of forests in the past 20 years.
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