Grassland or Forest?

[Sam Carana]

One scientist's hobby: recreating the ice age - AP
http://news.yahoo.com/s/ap/20101127/ap_on_re_eu/eu_russia_ice_age_park

Could reintroducing wildlife in northern Siberia slow global warming?

The idea is that wild horses, moose and reindeer, perhaps followed by
other deer and bison, would slow global warming. Grazing and trampling
would encourage the growth of grass. Trampling herds would compress
the snow and the soil, creating an insulator that prevents the soil
from thawing and that keeps permafrost frozen. Furthermore, grass and
snow will reflect sunlight more, as opposed to darker-colored tundra
and forest that would absorb more sunlight.

Questions:
1. Would above benefits be outweighed by the fact that grazing animals
would cause additional emissions, through digestion and through their
manure?
2. Would grassland indeed form, or would compressing the soil due to
trampling instead contribute to the formation of swamps and wetlands
that cause additional emissions?

What's you view? Is grassland a better alternative than tundra and
forest? Is this initiative to be recommended?

Cheers,
Sam Carana