Forest Influences on Climate and Water Resources at the Landscape to Regional Scale - Landscape Ecology for Sustainable Environment and Culture - page 315

15.5.1 Understanding Feedbacks Within the Forest-Climate-
Human Systems
Our knowledge about how forests will respond to climate change is limited and we
know little about the consequences of management options designed to combat
climate change. For example, schemes to increase carbon sequestrations in man-
made forests through REDD+ (reducing greenhouse gas emissions from defores-
tation and forest degradation) could negatively impacts biodiversity (Parrotta 2012 )
and water resources (Jackson et al. 2005 ) and the environment (Cao 2008 ) if not
properly implemented. We need to better understand the feedbacks between climate
change and human response and actions using a system approach (Avila et al. 2012 ).
Current climate change models are not reliable for local predictions and the Earth
system models that incorporate land surface processes and atmospheric processes
and human influences are still in their infancy (Bonan 2008 ; Angelini et al. 2011 ).
Forests can affect regional climate processes and variability at long time scales
(Notaro and Liu, 2006 ; 2008 ). Similar to oceans, the land has the capacity to retain
anomalous signals over a much longer period than the atmosphere. Land surface
processes could contribute to long-term atmospheric variability by passing their
relatively slow anomalous signals to the atmosphere (e.g., Yeh et al. 1984 ; Dick-
inson and Handerson-Sellers 1988 ; Delworth and Manabe 1988 ; Vinnikov et al.
1996 ; Liu and Avissar 1999 ; Koster and Suarez 1995 ).
Forest-climate interactions contribute to local and regional climate variability at
interannual and decadal scales (Zeng et al. 2000 ). Landscapes in Amazon, the
Sahel, western Africa tropical rainfall forests, northwest China have changed
dramatically since the 1970s as a result of deforestation and over-cultivation
(Sampson 2004 ). These changes have been linked to some regional climate
disasters such as the prolonged drought in northern Africa during the 1970s
(Charney 1975 ; Xue and Shukla 1993 ) and flooding and dust storms in China. The
declined vegetation converge in the southern United States in the 19th century and
early 20th century due to agriculture and industrial activities might be a contrib-
utor to the drying climate and severe dust bowls during the 1930s. Future global
climate change suggests ted that a large portion of the temperate deciduous forests
in the Southeast would be replaced with temperate deciduous savanna in response
to the projected climate change (Neilson et al. 1998 , 2005 ). Notaro et al. ( 2007 )
indicated that, for the projected future climate change due to the greenhouse effect,
tree coverage is expected to increase in many regions, including southeastern U.S.
Studying land-atmosphere interaction has emerged as one of the most active
research areas in atmospheric and hydrological sciences in the past decades, partly
due to the increasing attention to human activity related to regional environmental
changes (Bonna 2008 ).