Measuring carbon and nitrogen accumulation on abandoned farmland
A WED researcher and a University of Rhode Island graduate student examined carbon (C) and nitrogen (N) accumulation on forest land in Rhode Island that had been cleared and farmed more than a century ago. Eastern forests are regrowing after extensive clearing and agriculture during the last three centuries, and are expected to store globally important amounts of atmospheric C and N as they grow. By studying sites with similar soils and vegetation but where farming had stopped for at least 10 to nearly 115 years, the researchers were able to measure the rates of C and N storage in plants, soil and litter.
They found that total ecosystem C is accumulating at a constant rate, indicating that regrowing forests on abandoned farmland are, indeed, a substantial sink for C. In contrast, total ecosystem N did not change over time, which is surprising given that atmospheric N deposition has risen dramatically during the last century. Their work indicates that Rhode Islandís forests, 65 percent of which were established after 1900, will continue to store C, and that over the long term, redistribution of soil N to wood will be important in the regrowth of Eastern forests. (Contact J.E. Compton, 541-754-4620; firstname.lastname@example.org)