Export of nutrients and recovery of stable conditions following deforestation at Hubbard Brook

Journal Article · · Ecol. Monogr.; (United States)

DOI:https://doi.org/10.2307/2937031· OSTI ID:6059323

Bormann, F H; Likens, G E; Siccama, T G; Pierce, R S; Eaton, J S

The effects of deforestation on the export of particulate matter, erodibility of the ecosystem, and the relative importance of dissolved substances and particulate matter in exported materials are reported. The mature forested ecosystem is little affected by erosion, with an average annual particulate matter export of only 2.5 MT (metric tons) km/sup -2/ yr/sup -1/. Deforestation and repression of growth for 3 years increased export to a maximum of 38 MT km/sup -2/year/sup -1/, but the increase in export was exponential with rather minor increases in the first 2 years after cutting and a sharp increase in the 3rd year. This resulted because the ecosystem continued to exercise considerable control over erodibility for 2 years after cutting without annual renewal of biotic regulation by primary productivity. Increases in particulate matter export are primarily due to increases in erodibility rather than increased flow rates. The first response to deforestation is mobilization of nutrients from the available nutrient and organic matter compartments and leakage in stream water. After 2 years, particulate matter output rises sharply as biotic control of erodibility weakens, while dissolved substance export declines, probably because of diminution of readily available nutrients stored within the system. Thus, following destruction of the vegetation, the ecosystem maintains a residual resistance to erosion and has a high potential for repair through successional productivity. Nutrient flux and erosion losses return to previous levels as the intrasystem aspects of the hydrologic-nutrient cycle interaction and erodibility are increasingly regulated by biotic factors. These results relative to stable conditions and their reestablishment following disturbance may have applicability to a wide range of terrestrial ecosystems. 61 references, 12 figures, 10 tables.

• Research Organization: Yale Univ. School of Forestry and Environmental Studies, New Haven, CT
• OSTI ID: 6059323
• Journal Information: Ecol. Monogr.; (United States), Journal Name: Ecol. Monogr.; (United States) Vol. 44:3; ISSN ECMOA
• Country of Publication: United States
• Language: English

Related Subjects

510100* -- Environment
Terrestrial-- Basic Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
BIOLOGICAL FUNCTIONS
DATA
ECOSYSTEMS
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL TRANSPORT
EROSION
EXPERIMENTAL DATA
FORESTS
FUNCTIONS
INFORMATION
LAND USE
MASS TRANSFER
MINERAL CYCLING
NUMERICAL DATA
NUTRIENTS
PARTICLES
PARTICULATES
TERRESTRIAL ECOSYSTEMS