Estimating salal leaf area index and leaf biomass from diffuse light attenuation

1990 ◽  
Vol 20 (9) ◽  
pp. 1265-1270 ◽  
Author(s):  
N. J. Smith ◽  
D. R. Clark
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Light Attenuation ◽  
Major Axis ◽  
Weibull Model ◽  
Leaf Biomass ◽  
Diffuse Light ◽  
Area Index ◽  
Extinction Coefficients ◽  
Reduced Major Axis

Salal (Gaultheriashallon Pursh) leaf area index and leaf biomass were estimated from 37 quadrat samples in 13 stands dominated by Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) on eastern Vancouver Island, British Columbia. Leaf area index and biomass were predicted from a Beer's Law light attenuation model using diffuse photosynthetically active radiation (400–700 nm wavelength). The extinction coefficients, determined using reduced major axis maximum likelihood, were 0.8055 m2/m2 for leaf area index and 0.0069 g/m2 for leaf biomass. Salal leaf area index and biomass were then predicted for any convenient height in the understory canopy using a cumulative Weibull model based on dominant salal height per quadrat. The models are of use for objectively assessing the amount of Columbian black-tailed deer (Odocoileushemionuscolumbianus Richardson) winter browse and to quantify competitive leaf area.

CANOPY CHARACTERISTICS OF CONTRASTING CLONES OF CACAO (THEOBROMA CACAO)

2002 ◽  
Vol 38 (3) ◽  
pp. 359-367 ◽  
Author(s):  
A. J. Daymond ◽  
P. Hadley ◽  
R. C. R. Machado ◽  
E. Ng
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Theobroma Cacao ◽  
Light Interception ◽  
Canopy Architecture ◽  
Mature Trees ◽  
Area Index ◽  
Mean Values ◽  
Extinction Coefficients ◽  
The Relationship

Canopy characteristics (leaf area index, fractional light interception, extinction coefficient) of mature trees of ten clonally propagated cacao cultivars were measured over a period of 14 months at an experiment site in Bahia, Brazil. Differences in leaf area index between clones became more pronounced over time. When an approximately constant leaf area index was reached (after about nine months), the leaf area index varied between clones from 2.8 to 4.5. Clonal differences in the relationship between leaf area index and fractional light interception implied differences in canopy architecture, as reflected by the range of extinction coefficients (mean values ranged from 0.63 for the clone TSH-565 to 0.82 for CC-10). The results demonstrate the potential for breeding more photosynthetically efficient cacao canopies.

scholarly journals Switchgrass Leaf Area Index and Light Extinction Coefficients

2011 ◽  
Vol 103 (1) ◽  
pp. 119-122 ◽  
Author(s):  
Jim Kiniry ◽  
Mari-Vaughn Johnson ◽  
Robert Mitchell ◽  
Ken Vogel ◽  
Jerry Kaiser ◽  
...  
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Light Extinction ◽  
Area Index ◽  
Extinction Coefficients

scholarly journals Remote estimation of leaf area index and green leaf biomass in maize canopies

2003 ◽  
Vol 30 (5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Anatoly A. Gitelson ◽  
Andrés Viña ◽  
Timothy J. Arkebauer ◽  
Donald C. Rundquist ◽  
Galina Keydan ◽  
...  
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Green Leaf ◽  
Leaf Biomass ◽  
Area Index ◽  
Remote Estimation

Sun and shade leaves: clues to how salal (Gaultheriashallon) responds to overstory stand density

1991 ◽  
Vol 21 (3) ◽  
pp. 300-305 ◽  
Author(s):  
N. J. Smith
Keyword(s):  
Leaf Area Index ◽  
Relative Density ◽  
Leaf Area ◽  
Stand Density ◽  
Leaf Biomass ◽  
Area Index ◽  
Sun And Shade Leaves ◽  
Sun And Shade ◽  
Shade Leaves ◽  
Sun Leaves

Salal (Gaultheriashallon Pursh) leaf biomass, leaf area index, specific leaf area, and leaf morphology were examined in 13 Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands from 37 destructively measured 1-m2 quadrats. In response to light and stand overstory density, salal shoots produced either mainly sun leaves or mainly shade leaves. Sun leaves were associated with sunflecks in open-grown or variably stocked stands. Shade leaves were associated with diffuse light under denser stands. Sun-leaf quadrats had mean specific leaf areas less than 90 cm2/g; shade-leaf quadrats had mean specific leaf areas greater than 90 cm2/g. Sun leaves were narrower, with average leaf widths less than 5 cm. Quadrat salal leaf biomass and leaf area index peaked at Curtis' metric relative density 5.9, which corresponded to an availability of 15% of global photosynthetically active radiation. Sun-leaf quadrats occurred below relative density 5; shade-leaf quadrats occurred above relative density 4. A mixture of sun- and shade-leaf quadrats occurred between about relative density 4 and 5, depending on the uniformity of stocking.

LEAF-AREA INDEX AND LIGHT ATTENUATION IN RAPIDLY EXPANDING SHRUB THICKETS

Ecology ◽  
2007 ◽  
Vol 88 (2) ◽  
pp. 524-530 ◽  
Author(s):  
Steven T. Brantley ◽  
Donald R. Young
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Light Attenuation ◽  
Area Index

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.

Increases in aboveground biomass and leaf area 85 years after drainage in a bog

Botany ◽  
2014 ◽  
Vol 92 (10) ◽  
pp. 713-721 ◽  
Author(s):  
Julie Talbot ◽  
Nigel T. Roulet ◽  
Oliver Sonnentag ◽  
Tim R. Moore
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Aboveground Biomass ◽  
Reference Site ◽  
Carbon Sink ◽  
Tree Canopy ◽  
Optical Measurements ◽  
Leaf Biomass ◽  
Climate Change Scenarios ◽  
Area Index

Climate change scenarios suggest that northern peatlands could become drier. To address the type and magnitude of vegetation change associated with persistent drying, we studied changes in biomass and leaf area index following drainage 85 years previously of a bog, using destructive sampling, allometric relationships, and optical measurements. Our results show a 10-fold increase in aboveground biomass between the reference site and the most severely drained site, resulting from the growth of a tree layer. The total leaf biomass increased slightly as a result of drainage, thus an increase in woody biomass was the main cause of the increase in aboveground biomass. Leaf area index approximately tripled in sites where trees grew. Sphagnum L. moss biomass decreased from 120 g·m−2 at the reference site (20% of all aboveground biomass) to 8 g·m−2 under the tree canopy (<1% of all aboveground biomass). The percentage of deciduous shrubs increased from 3% of the total shrub biomass in the reference site to 72% in the most severely drained site. Our results show that lowering the water table of a bog can have a profound effect on vegetation but the net effect of these changes on the role of the peatland as a carbon sink remains difficult to assess.

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