Deforestation impacts temperature and ecosystems says CU-Boulder study
Feb. 23, 2016
Kika Tuff
Clearing forest impacts more than just the deforested area, according to new
research from CU-Boulder.
That’s because the edges of deforested areas are highly susceptible to drastic
temperature changes, leading to hotter, drier and more variable conditions for
the forest acreage that remains, says Kika Tuff, lead author of the new paper.
CUT 1 “You have these forests that are cool and moist and generate their
own moisture through evapotranspiration and when you cut down these areas
next to them, you create this really intense thermal contrast. (:14) So you have
cool and moist next to hot and dry and that cool and moist air starts to be
sucked out of the forest and run over the ground in these really hot and dry
areas just because of thermal dynamics.” (:27)
Tuff is a PhD candidate in the Department of Ecology and Evolutionary
Biology.
She says the thermo dynamics created by deforestation is altering the
ecosystem in a number of ways, including the creation of micro-weather
patterns.
CUT 2 “Not only do these hot spots of cleared areas suck the cool and moist
air out, but if they do that enough they start to form their own rain clouds in
the dry spot. (:13) So now it rains in the dry, hot spots. It doesn’t rain in the
forest where it should just because moisture is being sucked into these areas.
So you’ve got not only hotter but dryer and now fully altered weather
patterns that will perpetuate further drying.” (:30)
She says the findings suggest that thermal biology—an emerging discipline
that examines temperature variations and their ecological effects—could be
an effective tool for understanding how temperature changes in fragmented
habitats can potentially wreak havoc on species activity and other critical
ecosystem functions.
CUT 3 “In tropical forests we are the most concerned because you have
organisms that are used to very thermally stable conditions. They are used to
the same temperature all year round. So they develop these behaviors,
thermal behaviors, that are really precise. (:18) 30.2 degrees Celsius is their
optimum body temperature and they can handle a change of, like, 1 degree.
And so now you come in and you increase it 10 degrees in a day for species
that are the most sensitive and you have a serious problem.” (:33)
Tuff says one impact to species living in the edge environment might be the
timing and duration of species activity. As temperatures increase predators
may start foraging later in the day to avoid the heat. Such a change could
catch prey off guard, possibly resulting in localized species population
crashes.
CUT 4 “With some of the climate change literature we’ve seen a prey species
can start to become active later in the day and that can confound predation
events because their predators were naturally active later in the day, which is
why they foraged in the afternoon to begin with. (:16) So you have these
time-disconnects that start to converge and now you get these predation
events that are massive and take out a big chunk of the population.” (:25)
A study outlining a framework for applying thermal biology to deforestation
research was recently published in the journal Ecology Letters.
-CU-