There is a great article here, http://www.serc.si.edu/for_media/pr.aspx?pr_id=41 about how fast a forest can grow and some of the impacts this growth can have.
Has anyone ever wondered how fast a forest grows? We have a pretty good idea of how fast trees grow, but what about an entire forest ecosystem? For more than 20 years forest ecologist Geoffrey Parker has tracked the growth of 55 stands of mixed hardwood forest plots. Just like people, forests can become “overweight” and may even need to go on a diet!
These tree and forest studies have revealed that the forest is getting fat! It was discovered that, on average, a “typical” forest is growing an additional 2 tons per acre annually. That is the equivalent of a tree with a diameter of 2 feet sprouting up over a year. Because forests and their soils store the majority of the Earth’s carbon, small changes in their growth rate can have significant impact on weather patterns, nutrient cycles, climate change and biodiversity.
“Assessing how fast a forest is changing is no easy task. One way that Dr. Parker compensated for this was by creating a chronosequence – “a series of forests plots of the same type that are at different developmental stages”. By grouping the forest stands by age, scientists are also able to determine that the faster growth is a recent phenomenon. Just like the people that live in the countries these forests are found in, the have been “packing on some weight”!
These studies also provide an opportunity for people to get involved. Just like in Christmas Bird Counts, where bird enthusiasts count birds over a 24 hour period to help scientists understand bird populations, forest growth studies rely on a group of citizen scientists to take measurements. Volunteers are used to measure all trees that are 2 centimeters or more in diameter, identifiy the species, mark the tree’s coordinates and note if it is dead or alive. It’s hard work, but if you are a tree enthusiast, this can be a fun a rewarding time.
“Ecosystem responses are one of the major uncertainties in predicting the effects of climate change. Many people think there is every reason to believe that these study sites are representative of the Eastern deciduous forest”, the regional ecosystem that surrounds many of the population centers on the East Coast, including our area. This is happening in our own backyard!