Woodland attenuation shows a characteristic peak-dip-rise spectral shape
Evidence
Measured data for the attenuation spectra in various woodlands display a characteristic shape with a low-frequency peak, or peaks, a midfrequency dip, and a net increase with frequency above this dip. A composite model that includes ground effect and multiple scattering by two arrays, one of which corresponds in dimensions and density to the trunks and the other to the foliage, has been shown to be able to predict this characteristic shape and its variation with vegetation structure, density, and range. — Margaret A. Price, Keith Attenborough, and Nicholas W. Heap, Sound Attenuation through Trees, 105
Categorization
- XREF: If leaf-on spectra show a foliage-driven mid-to-high frequency rise that collapses in leaf-off, the signature shape itself becomes the leaf presence detector in the soundscape method. — connects to: Trunk scatter cannot alone explain forest high-frequency sound attenuation — Margaret A. Price, Keith Attenborough, and Nicholas W. Heap, Sound Attenuation through Trees:…, 87; Excess attenuation increases with frequency in vegetated habitats — Almo Farina, Soundscape Ecology: Principles,…, 418
Related
- Trunk scatter cannot alone explain forest high-frequency sound attenuation (similarity 0.89)
- Leaf width and canopy leaf area drive sound scattering in dense vegetation (similarity 0.87)
- Excess attenuation increases with frequency in vegetated habitats (similarity 0.87)
- Margaret A. Price, Keith Attenborough, and Nicholas W. Heap — Sound Attenuation through Trees Measurements and Models (similarity 0.85)
- Woods sound attenuation stays near constant regardless of optical visibility through the canopy. (similarity 0.84)
- Vegetation attenuation thresholds differ measurably across cover types and soil states (similarity 0.83)
- Ground-effect interference fades at higher frequencies and longer ranges (similarity 0.81)
- Ground and vegetation attenuate noise in complementary frequency ranges. (similarity 0.81)
- Vegetation substrate type shapes the spectral character of wind noise (similarity 0.80)
- Ground impedance, not foliage, governs low-band attenuation by vegetation. (similarity 0.79)
- Dense multi-layered jungle vegetation makes hearing more efficient than sight (similarity 0.79)
- Mature woodland humus layers do not behave as locally reacting acoustic grounds (similarity 0.79)
- Prior noise studies conflicted after omitting ground attenuation as a variable. (similarity 0.79)
- Tree branches, not leaves or twigs, resonate as forced acoustic oscillators near 275-450 cps. (similarity 0.79)
Broader Connections
- Excess attenuation increases with frequency in vegetated habitats
#expands(0.80) — Almo Farina, Soundscape Ecology, 418