OLYMPIC-NATIONAL-PARK
; MONTANE CLOUD FOREST
; WESTERN OREGON
; REMNANT TREES
; BIGLEAF MAPLE
; QUEETS RIVER
; CANOPY SOILS
; SITKA SPRUCE
; BIOMASS
; COMMUNITIES
WOS学科分类:
Plant Sciences
; Ecology
WOS研究方向:
Plant Sciences
; Environmental Sciences & Ecology
英文摘要:
Aims Epiphytes are an abundant and diverse component of many wet temperate forests and have significant roles in ecosystem processes. Little is known about the processes and rates of their death and decomposition when they fall from the canopy, which limits our understanding of their role in forest carbon sequestration and nutrient cycling. In the temperate rainforest of the Quinault River Valley, Washington State, our aim was to test hypotheses regarding four elements of disturbance that might contribute to their decline.
Methods We established set of experiments in which we placed samples of canopy epiphytes and their branch segments: (i) in the canopy versus forest floor microenvironment (stratum); (ii) attached to live versus dead branch substrates; (iii) subjected to physical disruption and jarring'; and (iv) in direct versus indirect contact with the forest floor. Over the 2-year study, we assigned a non-destructive vitality index' (based on color and apparent mortality and dryness) to each sample every 2-3 months to compare effects of the experimental treatments and analyzed with a statistical model and post hoc pairwise comparisons of treatments.
Important Findings The canopy versus ground stratum and live/dead branch status significantly affected epiphyte vitality. Effects of physical disruption and ground contact were not significant. There were seasonal effects (low vitality during the sampling times in the summer, revitalization upon sampling times in the winter) for all treatments except samples in contact with the ground. One implication of these results relates to effects of climate change, which is predicted to shift to hotter, drier summers and wetter winters. Climate change may affect forest dynamics and nutrient cycling in unpredictable ways. Results also point to future experiments to understand biotic and abiotic effects on epiphyte disturbance and dynamics.
1.Univ Utah, Dept Biol, 257 South 1400 East, Salt Lake City, UT 84112 USA 2.Univ Pittsburgh, Dept Biol Sci, 403B Clapp Hall,4249 Fifth Ave, Pittsburgh, PA 15260 USA
Recommended Citation:
Nadkarni, Nalini M.,Kohl, Kevin D.. Elements of disturbance that affect epiphyte vitality in a temperate rainforest: an experimental approach[J]. JOURNAL OF PLANT ECOLOGY,2019-01-01,12(2):306-313