Across the deforestation frontier in eastern Amazonia, we examined the relationship between edge-related forest desiccation and deforestation patterns using remote-sensing techniques. Canopy-moisture levels were estimated over an eight-year period in three study sites that encompassed similar to 100,000 km(2) in area. We found four main effects of deforestation on dry-season canopy desiccation. First, intact forests showed no detectable change in canopy water content whereas forests adjacent to clearings showed significant water loss. Second, the distance to which edge-related desiccation penetrated into forest interiors varied among landscapes with differing forest loss and fragmentation. In moderately fragmented landscapes (with 65% and 51% remaining forest cover), canopy desiccation extended 1-1.5 km into forest interiors, whereas in heavily fragmented landscapes (20% forest cover) desiccation penetrated up to 2.7 km into forests. Third, the magnitude of edge-related desiccation varied among landscapes with differing fragmentation. Moderately fragmented landscapes exhibited a greater magnitude of change in canopy-water loss over the first 1 km from an edge than did heavily fragmented landscapes. Finally, forest desiccation penetrated further into forests over time in the moderately fragmented landscapes, but not in the heavily fragmented landscape, where edge-related desiccation had evidently 'saturated' remaining forests. We conclude that protracted dry seasons will have far more serious effects on fragmented than intact rainforests, with the former becoming highly vulnerable to destructive fires. With similar to 30,000 km of new forest edge being created annually in Brazilian Amazonia, these finding have serious implications for forest conservation. (C) 2010 Elsevier Ltd. All rights reserved.
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Stanford Univ, Dept Biol Sci, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Broadbent, Eben N.
;
Asner, Gregory P.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Asner, Gregory P.
;
Keller, Michael
论文数: 0引用数: 0
h-index: 0
机构:
USDA, Forest Serv, Int Inst Trop Forestry, Rio Piedras, PR USA
Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Keller, Michael
;
Knapp, David E.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Knapp, David E.
;
Oliveira, Paulo J. C.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Oliveira, Paulo J. C.
;
Silva, Jose N.
论文数: 0引用数: 0
h-index: 0
机构:
EMBRAPA Amazonia Oriental, BR-66095100 Belem, Para, BrazilCarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
机构:
Michigan State Univ, Basic Sci & Remote Sensing Initiat, E Lansing, MI 48823 USAMichigan State Univ, Basic Sci & Remote Sensing Initiat, E Lansing, MI 48823 USA
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Stanford Univ, Dept Biol Sci, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Broadbent, Eben N.
;
Asner, Gregory P.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Asner, Gregory P.
;
Keller, Michael
论文数: 0引用数: 0
h-index: 0
机构:
USDA, Forest Serv, Int Inst Trop Forestry, Rio Piedras, PR USA
Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Keller, Michael
;
Knapp, David E.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Knapp, David E.
;
Oliveira, Paulo J. C.
论文数: 0引用数: 0
h-index: 0
机构:
Carnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USACarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
Oliveira, Paulo J. C.
;
Silva, Jose N.
论文数: 0引用数: 0
h-index: 0
机构:
EMBRAPA Amazonia Oriental, BR-66095100 Belem, Para, BrazilCarnegie Inst Sci, Dept Global Ecol, Stanford, CA 94305 USA
机构:
Michigan State Univ, Basic Sci & Remote Sensing Initiat, E Lansing, MI 48823 USAMichigan State Univ, Basic Sci & Remote Sensing Initiat, E Lansing, MI 48823 USA