4.3 Implications of GE for grassland management
Following the implementation of the comprehensive ‘Returning Grazing
Land to Grassland’ project, GE has had a negative effect on soil pH in
China’s grassland ecosystems. In addition, soil acidification also had
lasted for decades and could be maintained for a long periods because of
the deposition of atmospheric N and sulfur across China’s grasslands
(Yang et al. , 2012). These two factors may be variably
superimposed. Sustained soil acidification could enhance the leaching
loss of base cations (e.g., Ca2+,
K+, Mg2+ and Na+),
and the release of
mobile
forms of Al3+ and Mn2+,
which
influences plant physiological activities (e.g., toxicity) for grassland
species (Kochian, 1995; Poschenrieder et al. , 2008). Long-term
soil acidification could also change structure and function at ecosystem
scale, such as C–N transformation processes
and
plant and microbial diversities (Liu et al. , 2011). Similar
management recommendations might be applied in other grassland
ecosystems with similar histories and patterns of ecological
degradation, such as the African savannas (Talore et al. , 2015),
temperate grassland of north America (Anderson et al. , 2008) and
Pampas of South America (Piñeiro et al. , 2009).