The consequences of massive deforestation and looming climate
change may most significantly exhibit themselves (in the medium
term) through water shortages. WWF highlights in "Running Pure:
The importance of forest protected areas to drinking water" at
http://www.panda.org/downloads/freshwater/runningpurereport.pdf
the importance ecologically and economically of forested
watersheds as a means to provide high quality drinking water.

Consequences of climate change on water resources are being felt
strongly as the World's glaciers are melting causing subsequent
water scarcity. Certainly there will be many other synergistic
impacts of terrestrial and atmospheric diminishment - including
forest die-back as fragmented forests are unable to migrate due
to warming that is unprecedented in its rapidity.

The impacts of deforestation and climate change - happening now
as a result of our choices and inaction - are going to
reverberate through the global ecological systems indefinitely.
This is why Forests.org focuses upon all three - water
(http://www.waterconserve.info/), climate change
(http://www.climateark.org/) and of course forests
(http://forests.org/). Each environmental crisis impacts and
is impacted upon by the others - together threatening global
ecological sustainability (http://www.eco-portal.com/) .

My ecological intuition leads me to conjecture that severe
shortages of water exacerbated by deforestation and climate
change - through the sheer magnitude of human suffering it will
cause - may be the first instance of ecological collapse that
will catch global humanity's attention. Only when the Earth is
torn asunder, impacting the comforts of the rich (while killing
more of the poor) is there likely to be ecological protection,
conservation and restoration projects adequate to the ecological
crisis humanity now faces. By then let us all hope it is not
too late to avert global ecocide.