Ecological restoration stimulates environmental outcomes but exacerbates
water shortage in the Loess Plateau
Abstract
Restoration is the natural and intervention-assisted set of processes
designed to promote and facilitate the recovery of an ecosystem that has
been degraded, damaged, or destroyed. Therefore, the need to assess an
ecological restoration project is a critical step to evaluate its
success and identify best management practices. We performed a
meta-analysis concerning the environmental outcomes during the years
2000 to 2015 resulting from the “Grain for Green” Project (GFGP)
implementation in the Loess Plateau (LP). Data were collected in 48
English-language peer-reviewed papers selected from a pool of 332
papers. The results showed that, on average, GFGP increased forest
coverage by 35.7% (95% CI: 24.15-47.52%), and grassland by 1.05%
(95% CI: 0.8-1.28%). At the same time, GFGP has a positive impact on
soil carbon (C) sequestration, net ecosystem production (NEP), and net
primary production (NPP), from the years 2000 to 2015 by an average of
36% (95% CI: 28.96-43.18%), 22.7% (95% CI: 9.10-36.79%), and
13.5% (95% CI: 9.44-17.354%), respectively. Soil erosion, sediment
load, runoff coefficient and water yield reduced by 13.3% (95% CI:
0.27%-25.76), 21.5% (95% CI: 1.50-39.99%), 22.4% (95% CI:
5.28-40.45%) and 43.3% (95% CI: 27.03%-82.86%), respectively, from
the years 2000 to 2015. Our results indicate that water supply decreased
with restoration age. Therefore, GFGP policies and strategies should be
adjusted to balance the need for green space and grain trade by
recovering, enhancing, and maintaining more resilient landscapes.