The Export of Nutrients and Recovery of Stable Conditions Following Deforestation at Hubbard Brook

作者：Franz–Josef Bormann, Gene E. Likens, Thomas G. Siccama, Robert S. Pierce, John S. Eaton · 发表于：Ecological Monographs · 年份：1974 · DOI：10.2307/2937031 · 被引用次数：318 · 研究领域：Hydrology and Sediment Transport Processes、Soil erosion and sediment transport、Hydrology and Watershed Management Studies

We report 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. The mature forested ecosystem is little affected by erosion, with an average annual particulate matter export of only 2.5 MT (metric tons) km—2 yr—1. Deforestation and repression of growth for 3 yr increased export to a maximum of 38 MT km—2 yr—1, but the increase in export was exponential with rather minor increases in the first 2 yr after cutting and a sharp increase in the 3rd yr. This resulted because the ecosystem continued to exercise considerable control over erodibility for 2 yr 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. In the mature ecosystem, the average ratio of annual net export of dissolved substance to particulate matter is 2.3. Deforestation shifts this ratio to >8.0 during the first 2 yr after cutting. This shift results because the export trends, for dissolved substances and particulate matter following deforestation, are not synchronous. The first response to deforestation is mobilization of nutrients from the available nutrient and organic matter compartments and leakage in stream water. After 2 yr, particulate matter output rises sharply as biotic control of erodibility weakens, while dissolved subs...