Assessment of allometric algorithms for estimating leaf biomass, leaf area index and litter fall in different-aged Sitka spruce forests

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.

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

Canadian Journal of Forest Research ◽

10.1139/x90-168 ◽

1990 ◽

Vol 20 (9) ◽

pp. 1265-1270 ◽

Cited By ~ 7

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.

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A comparison of four methods for determining leaf area index in successional hardwood forests

Canadian Journal of Forest Research ◽

10.1139/x85-187 ◽

1985 ◽

Vol 15 (6) ◽

pp. 1154-1158 ◽

Cited By ~ 22

Author(s):

Thomas W. Jurik ◽

George M. Briggs ◽

David M. Gates

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Hardwood Forests ◽

Litter Fall ◽

Area Index ◽

Tree Diameter ◽

Leaf Mass ◽

The Vertical Distribution ◽

Harvest Method ◽

Do So

Four methods of determining leaf area index of three successional hardwood forests in northern lower Michigan were compared. Direct harvests gave values for leaf area index ranging from 1.4 to 3.6. Estimates of leaf area index derived from litter fall data were consistently higher than the harvest values and were highly dependent on the ratio of leaf area to leaf mass, which had to be estimated. A visual method using sightings through a tube gave values consistently lower (by 27–42%) than the harvest values. Calculations of leaf area index based on regressions of leaf mass versus tree diameter gave results very close to the harvest values for each site as a whole; calculations for smaller plots were more variable. The harvest method allowed measurement of the vertical distribution of leaf area; the other methods could not do so.

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Canopy leaf area index and litter fall in stands of the mangrove Rhizophora apiculata of different age in the Mekong Delta, Vietnam

Aquatic Botany ◽

10.1016/s0304-3770(99)00081-9 ◽

2000 ◽

Vol 66 (4) ◽

pp. 311-320 ◽

Cited By ~ 46

Author(s):

Barry Clough ◽

Dang Trung Tan ◽

Do Xuan Phuong ◽

Dang Cong Buu

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Mekong Delta ◽

Litter Fall ◽

Area Index ◽

Rhizophora Apiculata

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Vertical leaf area distribution, light transmittance, and application of the Beer–Lambert Law in four mature hardwood stands in the southern Appalachians

Canadian Journal of Forest Research ◽

10.1139/x95-113 ◽

1995 ◽

Vol 25 (6) ◽

pp. 1036-1043 ◽

Cited By ~ 77

Author(s):

James M. Vose ◽

Barton D. Clinton ◽

Neal H. Sullivan ◽

Paul V. Bolstad

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Independent Set ◽

Light Transmittance ◽

Litter Fall ◽

Validation Data ◽

Area Index ◽

Vertical Leaf ◽

Area Distribution ◽

Leaf Area Distribution

We quantified stand leaf area index and vertical leaf area distribution, and developed canopy extinction coefficients (k), in four mature hardwood stands. Leaf area index, calculated from litter fall and specific leaf area (c2•g−1), ranged from 4.3 to 5.4 m2•m−2. In three of the four stands, leaf area was distributed in the upper canopy. In the other stand, leaf area was uniformly distributed throughout the canopy. Variation in vertical leaf area distribution was related to the size and density of upper and lower canopy trees. Light transmittance through the canopies followed the Beer–Lambert Law, and k values ranged from 0.53 to 0.67. Application of these k values to an independent set of five hardwood stands with validation data for light transmittance and litter-fall leaf area index yielded variable results. For example, at k = 0.53, calculated leaf area index was within ± 10% of litter-fall estimates for three of the five sites, but from −35 to + 85% different for two other sites. Averaged across all validation sites, litter-fall leaf area index and Beer-Lambert leaf area index predictions were in much closer agreement ( ± 7 to ± 15%).

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

Canadian Journal of Forest Research ◽

10.1139/x86-227 ◽

1986 ◽

Vol 16 (6) ◽

pp. 1283-1288 ◽

Cited By ~ 18

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.

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

Botany ◽

10.1139/cjb-2013-0319 ◽

2014 ◽

Vol 92 (10) ◽

pp. 713-721 ◽

Cited By ~ 9

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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