Comparison of Methods of Estimating Leaf-Area Index In Old-Growth Douglas-Fir

Ecology ◽  
1986 ◽  
Vol 67 (4) ◽  
pp. 975-979 ◽  
Author(s):  
J. D. Marshall ◽  
R. H. Waring
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Douglas Fir ◽  
Comparison Of Methods ◽  
Old Growth ◽  
Area Index

Leaf area index of an old-growth Douglas-fir forest estimated from direct structural measurements in the canopy

2000 ◽  
Vol 30 (12) ◽  
pp. 1922-1930 ◽  
Author(s):  
Sean C Thomas ◽  
William E Winner
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Understory Vegetation ◽  
Western Hemlock ◽  
Old Growth ◽  
Area Index ◽  
Contact Frequency ◽  
Canopy Access

Leaf area index (LAI) in old-growth Douglas-fir (Pseudotsuga menziesii var menziesii (Mirb.) Franco) forests exceeds that of any other forest ecosystem by some estimates; however, LAI determinations in coniferous forests have generally been indirect, involving extrapolations of patterns observed in younger stands. Aided by a 75-m construction crane for canopy access, we used a vertical line-intercept method to estimate LAI for a [Formula: see text]450-year-old Douglas-fir - western hemlock (Tsuga heterophylla (Raf.) Sarg.) forest in southwestern Washington state. LAI was calculated as the product of foliage contact frequency and an "extinction coefficient" accounting for foliage angular distribution, geometry, and the ratio of "interceptable" to total leaf area. LAI estimates were 9.3 ± 2.1 (estimate ± 95% confidence interval), 8.5 ± 2.2, and 8.2 ± 1.8 in 1997, 1998, and 1999, respectively, or 8.6 ± 1.1 pooled across years. Understory vegetation, including foliage of woody stems <5 cm diameter, represented 20% of this total. Sample points in which Douglas-fir was dominant had a higher total LAI than points dominated by western hemlock, including a higher LAI of understory vegetation. Our results do not support the contention that old-growth Douglas-fir - western hemlock forests maintain an appreciably higher LAI than do other forest ecosystems. Moreover, LAI in very old stands may decline as western hemlock replaces Douglas-fir through the course of succession.

scholarly journals Estimate of Leaf Area Index in an Old-Growth Mixed Broadleaved-Korean Pine Forest in Northeastern China

PLoS ONE ◽  
2012 ◽  
Vol 7 (3) ◽  
pp. e32155 ◽  
Author(s):  
Zhili Liu ◽  
Guangze Jin ◽  
Yujiao Qi
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Northeastern China ◽  
Pine Forest ◽  
Korean Pine ◽  
Old Growth ◽  
Area Index ◽  
Korean Pine Forest

Determinants of leaf area index and understorey light availability in New Zealand old‐growth forests

2020 ◽  
Vol 47 (4) ◽  
pp. 941-954
Author(s):  
Rocío Fritz ◽  
Christopher H. Lusk
Keyword(s):  
New Zealand ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Light Availability ◽  
Old Growth ◽  
Area Index ◽  
Old Growth Forests

Using high-resolution airborne spectral data to estimate forest leaf area and stand structure

1991 ◽  
Vol 21 (7) ◽  
pp. 1127-1132 ◽  
Author(s):  
N. J. Smith ◽  
G. A. Borstad ◽  
D. A. Hill ◽  
R. C. Kerr
Keyword(s):  
High Resolution ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Spectral Data ◽  
Near Infrared ◽  
Stand Structure ◽  
Douglas Fir ◽  
Area Index ◽  
Spectrum Data

Techniques are developed to estimate stand leaf area index using high-resolution airborne spectral imagery. Leaf area index on 8 m radius plots was found to be strongly related to the normalized ratio of wavelengths in the red (674–687 nm) and near infrared (751–755 nm) part of the spectrum. Data from 17 stands were used. Leaf area index estimates included both the overstory (Douglas-fir, Pseudotsugamenziesii Mirb. (Franco)) and the understory (salal, Gaultheriashallon Pursh) over a range of stem densities.

Estimating leaf area index and light extinction coefficients in stands of Douglas-fir (Pseudotsugamenziesii)

1993 ◽  
Vol 23 (2) ◽  
pp. 317-321 ◽  
Author(s):  
Nicholas J. Smith
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Extinction Coefficient ◽  
Photosynthetically Active Radiation ◽  
Douglas Fir ◽  
Regression Equations ◽  
Individual Tree ◽  
Area Index ◽  
Active Radiation ◽  
Wide Range

Both photosynthetically active radiation penetrating the overstory canopy and overstory leaf area index were determined in forty-three 12 × 12 m plots in even-aged Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands. Stands were located on the east side of Vancouver Island, British Columbia, between 300 and 800 m on flat to south-facing slopes and were from a wide range of stem densities and stocking levels. In nine core plots total tree leaf area index was estimated using regression equations from individual-tree stem diameter and stand relative density. A single extinction coefficient did not govern the attenuation of photosynthetically active radiation with respect to leaf area index. For a given leaf area index, the extinction coefficient was smaller at low relative densities because of the presence of canopy gaps. Light attenuation models assuming a single extinction coefficient seriously underpredict stand leaf area index, especially at low stand densities. A modified Beer's Law model was used to predict light penetration, which implicitly accounted for foliage clumping.

Eight-year responses of light interception, effective leaf area index, and stemwood production in fertilized stands of interior Douglas-fir (Pseudotsuga menziesii var. glauca)

2000 ◽  
Vol 30 (5) ◽  
pp. 733-743 ◽  
Author(s):  
Nick J Balster ◽  
John D Marshall
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Pseudotsuga Menziesii ◽  
Growth Efficiency ◽  
Light Interception ◽  
Douglas Fir ◽  
Area Index ◽  
Volume Production ◽  
High Fertilization ◽  
Effective Leaf Area Index

Data from 72 Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) plots across the Interior Northwest were used to determine whether (i) increased intercepted photosynthetically active radiation (%IPAR), effective leaf area index (LAIe), and stemwood volume production (cubic metres stemwood per hectare per year) could still be detected 7 or 8 years after nitrogen fertilization and (ii) fertilization would increase the efficiency by which light is converted into stemwood volume. Projected LAIe varied from 1.82 to 6.07 m2·m-2 on the control plots. The fertilized plots intercepted 9-11% more light than the control plots (P < 0.001); they also had 22-25% higher LAIe than the control plots (P < 0.001). Stemwood volume production increased by 25-29% relative to the control (P < 0.001) and increased exponentially with %IPAR across all study plots (R2 = 0.57). Stemwood growth efficiency averaged 12.0 ± 0.4 (mean ± SE), 13.5 ± 0.4, and 13.7 ± 0.4 m3·ha-1·a-1 per IPAR for the control, low fertilization, and high fertilization plots, respectively (P < 0.01). Fertilization thus induced increases in both light interception and the efficiency with which intercepted light was converted to stemwood across the region.

Specific leaf area and leaf area index distribution in a young Douglas-fir plantation

1986 ◽  
Vol 16 (6) ◽  
pp. 1283-1288 ◽  
Author(s):  
M. Borghetti ◽  
G. G. Vendramin ◽  
R. Giannini
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Specific Leaf Area ◽  
Leaf Age ◽  
Douglas Fir ◽  
Leaf Biomass ◽  
Normal Curve ◽  
Area Index ◽  
Area Distribution ◽  
Leaf Area Distribution

The spatial distribution of specific leaf area and leaf area index of needles in different age classes has been investigated in a young and unthinned Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) plantation in Central Italy through the destructive analysis of 12 trees sampled in four diameter size classes. Specific leaf area decreased with leaf age and from crown base to apex. A clear interaction between the effects of age and position on specific leaf area was demonstrated. For the whole canopy the vertical distribution of leaf area was well fitted by a normal curve equation, which explained 97% of the variation. The midpoint of the leaf area distribution, estimated as a parameter of the normal curve, was found to be 1.2 m below the mean canopy depth. The standard deviation of leaf area with respect to height was 16.4%. The midpoint of leaf area distribution decreased as leaf age increased and increased as diameter size class increased. Strong and significant linear relationships were found between leaf biomass, leaf area, sapwood area, and diameter at breast height.

Optical and litter collection methods for measuring leaf area index in an old-growth temperate forest in northeastern China

2013 ◽  
Vol 18 (5) ◽  
pp. 430-439 ◽  
Author(s):  
Yujiao Qi ◽  
Guangze Jin ◽  
Zhili Liu
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Temperate Forest ◽  
Northeastern China ◽  
Old Growth ◽  
Area Index ◽  
Collection Methods

scholarly journals Estimating leaf area index in different types of mature forest stands in Switzerland: a comparison of methods

2010 ◽  
Vol 129 (4) ◽  
pp. 543-562 ◽  
Author(s):  
Anne Thimonier ◽  
Isabella Sedivy ◽  
Patrick Schleppi
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Comparison Of Methods ◽  
Forest Stands ◽  
Area Index ◽  
Mature Forest ◽  
Different Types
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