New Perspectives on Nitrogen Cycling in the Temperate and Tropical Americas : Report of the International SCOPE Nitrogen Project
Inputs of nitrogen to terrestrial and aquatic ecosystems have increased several-fold over the last one hundred and fifty years, with the steepest increases during the last four decades. The expansion of fertilizer manu- facture and use, the increase in fossil fuel combustion, the intensification of animal husbandry, and widespread cultivation of N2 fixing crops have all contributed to the dramatic increase in N inputs. The increase has been most rapid in Northern Hemisphere (NH) temperate ecosystems, but presently subtropical and tropical regions of Asia are also experiencing an explosive increase in N inputs to terrestrial ecosystems (W. Chameides, pers. comm. ; Galloway et al. 1996). Projected increases in N deposition for these trop- ical and subtropical regions, with a high natural background of N inputs, exceed increases projected for temperate and arctic regions (Cleveland et al. submitted; Galloway et al. 1994; Holland & Lamarque 1997a). Compared to biological N fixation, N deposition is becoming a proportionately greater source of N to terrestrial and aquatic ecosystems worldwide (Vitousek et al. 1997). 6 The nitrogen contained in the atmosphere as N , 3. 9 * 10 Tg (Tg = 2 12 10 g), is the largest reservoir of N in the Earth system (Warneck 1988). However, this paper focuses on the nitrogen emissions and deposition that have been transformed from N2 into reactive forms that are biologically avail- able (e. g. Vitousek et al. 1997).
- Hardback | 293 pages
- 155 x 235 x 17.53mm | 675g
- 31 Jul 1999
- Dordrecht, Netherlands
- Reprinted from BIOGEOCHEMISTRY, 1999
- VI, 293 p.
Table of contents
Foreword; A.R. Townsend. An etymology of nitrogen; J.E. Corredor. Contemporary and pre-industrial global reactive nitrogen budgets; E.A. Holland, et al. Nitrogen stable isotopic composition of leaves and soil: tropical vs. temperate forests; L.A. Martinelli, et al. The globalization of N deposition: ecosystem consequences in tropical environments; P.A. Matson, et al. A nitrogen budget for late-successional hillslope Tabonuco Forest, Puerto Rico; T.J. Chestnut, et al. The impact of accelerating land-use change on the N-cycle of tropical aquatic ecosystems: current conditions and projected changes; J.A. Downing, et al. Nitrogen yields from undisturbed watersheds in the Americas; W.M. Lewis, et al. Nitrogen cycling and anthropogenic impact in the tropical interamerican seas; J.E. Corredor, et al. Ecosystem constraints to symbiotic nitrogen fixers: a simple model and its implications; P.M. Vitousek, C.B. Field. Do top-down and bottom-up controls interact to exclude nitrogen-fixing cyanobacteria from the plankton of estuaries? An exploration with a simulation model; R.W. Howarth, et al. The presence of nitrogen fixing legumes in terrestrial communities: evolutionary vs. ecological considerations; T.E. Crews. Nitrogen limitation in dryland ecosystems: responses to geographical and temporal variation in precipitation; D.U. Hooper, L. Johnson.