Influence of age on growth efficiency of Tsuga canadensis and Picea rubens trees in mixed-species, multiaged northern conifer stands

2002 ◽  
Vol 32 (11) ◽  
pp. 2032-2042 ◽  
Author(s):  
Robert S Seymour ◽  
Laura S Kenefic
Keyword(s):  
Leaf Area ◽  
Volume Growth ◽  
Growth Efficiency ◽  
Tsuga Canadensis ◽  
Picea Rubens ◽  
Tree Age ◽  
Tree Level ◽  
Mixed Species ◽  
Fundamental Relationship ◽  
Negative Effect

Well-known patterns in the fundamental relationship between tree-level stemwood volume increment (VINC) and projected leaf area (PLA) are examined and quantified for Tsuga canadensis (L.) Carrière (eastern hemlock) and Picea rubens Sarg. (red spruce) growing in managed, mixed-species, multiaged stands in east-central Maine, U.S.A. Both species follow a sigmoid pattern, suggesting a peak growth efficiency (GE, stemwood volume growth per unit of PLA) in mid- to upper-canopy trees with PLAs of less than half that of the largest trees sampled. Tree age negatively influenced the VINC–PLA relationship in the expected manner: at a given PLA, older trees produce less stemwood than younger ones. The combined effect of leaf area and age is accurately modeled with a Weibull-like function in which the asymptote is an index of tree maturity defined as tree age relative to an estimated maximum for the species. Although previous studies have independently documented both the sigmoid relationship between VINC and PLA and the negative effect of age, their conclusions have been confounded by the strong correlation between age and mean tree PLA. This study addresses both issues simultaneously, and is the first to demonstrate a decline in GE with age independent from the effect of increasing PLA.

The effect of local stand structure on growth and growth efficiency in heterogeneous stands of ponderosa pine and lodgepole pine in central Oregon

2004 ◽  
Vol 34 (11) ◽  
pp. 2217-2229 ◽  
Author(s):  
Douglas B Mainwaring ◽  
Douglas A Maguire
Keyword(s):  
Leaf Area ◽  
Ponderosa Pine ◽  
Lodgepole Pine ◽  
Volume Growth ◽  
Basal Area ◽  
Growth Efficiency ◽  
Projection Area ◽  
Sapwood Area ◽  
Negative Effect ◽  
Crown Projection Area

Basal area and height growth were analyzed for individual trees in uneven-aged ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex. Loud.) stands in central Oregon. Basal area growth was modeled as a function of other stand and tree variables to address three general objectives: (1) to compare the predictive ability of distance-dependent versus distance-independent stand density variables; (2) to determine the degree to which small trees negatively affect the growth of overstory trees; and (3) to test for differences in growth efficiency between species and between indices of spatial occupancy used to define efficiency (area potentially available, crown projection area, and a surrogate for total tree leaf area). Distance-dependent variables were found to improve growth predictions when added to models with only distance-independent variables, and small trees were found to have a quantifiably negative effect on the growth of larger trees. While volume growth efficiency declined with increasing levels of spatial occupancy for lodgepole pine, ponderosa pine volume growth efficiency was greatest at the highest levels of crown base sapwood area and crown projection area. The behavior in ponderosa pine resulted from the previously recognized correlation between tree height and total leaf area or crown size. The final statistical models distinguished between the positive effect of relative height and the negative effect of increasing tree size.

Crown structure and growth efficiency of red spruce in uneven-aged, mixed-species stands in Maine

1998 ◽  
Vol 28 (8) ◽  
pp. 1233-1240 ◽  
Author(s):  
Douglas A Maguire ◽  
John C Brissette ◽  
Lianhong Gu
Keyword(s):  
Leaf Area ◽  
Volume Growth ◽  
Growth Efficiency ◽  
Tree Size ◽  
Red Spruce ◽  
Stem Volume ◽  
Mixed Species ◽  
Individual Tree ◽  
South Central ◽  
Tree Leaf

Several hypotheses about the relationships among individual tree growth, tree leaf area, and relative tree size or position were tested with red spruce (Picea rubens Sarg.) growing in uneven-aged, mixed-species forests of south-central Maine, U.S.A. Based on data from 65 sample trees, predictive models were developed to (i)estimate the amount of foliage held by individual trees from sapwood cross-sectional area and (ii)define the relationship between stem volume growth and three variables: total foliage area, relative position in the stand, and the degree of past suppression. A model that included variables representing tree size (or relative social position) and degree of past suppression (live branch whorls per unit crown length) indicated that stem volume growth first increased but later decreased over leaf area when other variables were held constant. Growth efficiency declined with increasing tree leaf area, although greater height and diameter enhanced growth efficiency and greater past suppression diminished growth efficiency. The decline in growth efficiency with greater leaf area likely is attributable to one or several of the factors previously identified as contributing to growth declines in mature, even-aged stands.

The effects of nutrition and density on growth, foliage biomass, and growth efficiency of high-density fire-origin lodgepole pine in central British Columbia

2005 ◽  
Vol 35 (12) ◽  
pp. 2851-2859 ◽  
Author(s):  
David P Blevins ◽  
Cindy E Prescott ◽  
H Lee Allen ◽  
Teresa A Newsome
Keyword(s):  
British Columbia ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Volume Growth ◽  
Growth Efficiency ◽  
High Density ◽  
Limited Resources ◽  
Tree Level ◽  
Stand Growth ◽  
Fire Origin

A factorial thinning and fertilization experiment was established in central British Columbia in a 36-year-old high-density fire-origin lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) stand to examine the effects of density, nutrition, and their interaction on tree and stand growth, foliage biomass per hectare, and growth efficiency. Volume growth was increased from 2 to 7 m3·ha–1·year–1 when fertilizer was applied without thinning and to 5 m3·ha–1·year–1 when fertilizer was applied with thinning. Thinning increased tree-level foliage biomass and growth efficiency by concentrating limited resources onto fewer trees, resulting in increased tree-level volume growth. Stand-level volume growth was reduced by thinning because of the large reduction in stocking. However, by year 4, stand-level volume growth was the same on control and thinned plots, suggesting that thinned trees have already recaptured the site potential. Fertilization increased both tree-level and stand-level productivity through increases in resource availability per tree and per hectare. This resulted in increased foliage biomass and growth efficiency at the tree and stand level. The combination of thinning and fertilization resulted in the greatest tree-level growth because of increased tree-level foliage biomass and growth efficiency. Boron appears to be the most limiting element followed by sulfur and nitrogen.

The effect of site quality on growth efficiency of upper crown class Picea rubens and Abies balsamea in Maine, USAPublication 3046 of the Maine Agricultural and Forestry Experiment Station.

2009 ◽  
Vol 39 (4) ◽  
pp. 777-784 ◽  
Author(s):  
R. Justin DeRose ◽  
Robert S. Seymour
Keyword(s):  
Leaf Area ◽  
Abies Balsamea ◽  
Growth Efficiency ◽  
Site Index ◽  
Picea Rubens ◽  
Site Quality ◽  
Experiment Station ◽  
Volume Increment

The influence of site index on growth efficiency was studied for 411 dominant and codominant Abies balsamea (L.) Mill. and Picea rubens Sarg. from 10 sites across Maine, USA. Young A. balsamea (n = 204) were from stands precommercially thinned 15–20 years ago and ranged in site index from 18.4 to 24.3, while the older P. rubens (n = 207) were from stands that were not precommercially thinned and ranged in site index from 13.1 to 17.8. We hypothesized that site index positively influences growth efficiency. The results showed that volume increment – leaf area relationships and growth efficiency increased significantly with site index for A. balsamea but were unaffected by site index for P. rubens. A monotonic decreasing pattern of growth efficiency over increasing leaf area was found for both species. When standardized per unit site index, growth efficiency behaved nonlinearly for both species.

scholarly journals Foliage and fine roots in terms of growth efficiency – a comparison between European beech and Norway spruce at early growth stages

2013 ◽  
Vol 59 (No. 11) ◽  
pp. 436-446 ◽  
Author(s):  
B. Konôpka ◽  
J. Pajtík
Keyword(s):  
Leaf Area ◽  
Norway Spruce ◽  
Fine Roots ◽  
Morphological Characteristics ◽  
European Beech ◽  
Growth Efficiency ◽  
Morphological Properties ◽  
Tree Level ◽  
Growth Stages ◽  
Root Tips

The quantification of stems (under- and overbark), foliage and fine roots in 14-year-old stands of European beech and Norway spruce grown on the same site were evaluated. Therefore, 60 trees of each species were sampled, dry masses of stems and foliage were established and expressed by allometric equations with stem diameter as an independent variable. The spruce allocated a much larger portion of biomass into the foliage than beech. The equations on a tree level were constructed also for specific leaf area and one-sided projected leaf area. Moreover, the quantity and morphological characteristics of fine roots in both stands were surveyed through soil coring. While standing stocks of fine roots were similar in the stands of both tree species, significant interspecies differences occurred in morphological properties of roots. Growth efficiency, expressing annual stem production on a variety of foliage and fine root parameters was calculated. The largest differences, specifically fivefold in favour of spruce, were found in growth efficiency based on a number of root tips.

The historical reconstruction of growth efficiency and its relationship to tree mortality in balsam fir ecosystems affected by spruce budworm

1994 ◽  
Vol 24 (11) ◽  
pp. 2208-2221 ◽  
Author(s):  
Marie R. Coyea ◽  
Hank A. Margolis
Keyword(s):  
Leaf Area ◽  
Tree Mortality ◽  
Basal Area ◽  
Spruce Budworm ◽  
Growth Efficiency ◽  
Balsam Fir ◽  
Tree Age ◽  
Basal Area Growth ◽  
Annual Growth Rings ◽  
Area Growth

The growth efficiencies (E; stemwood growth per unit leaf area) of balsam fir (Abiesbalsamea (L.) Mill.) trees from 20 stands were reconstructed over the 30-year period from 1960 to 1989 in order to determine if E could be used to predict tree mortality occurring during and after an epidemic of eastern spruce budworm (Choristoneurafumiferana (Clem.)). Growth efficiencies were reconstructed based on the relationship between age and the number of annual growth rings in the cross-sectional area of heartwood at breast height (R2 = 0.97) and on the previously demonstrated relationship between sapwood area and leaf area of balsam fir across a wide geographic area. Profile and logistic regression analyses demonstrated that apparent E (i.e., the historically reconstructed E) of surviving trees was greater than that of dead trees for every year of the 30-year analysis period. For trees in the 25- to 35-year age-class in 1960, apparent E was the only variable measured prior to the epidemic that was significantly related to balsam fir mortality. For all trees (aged 11 to 46 years in 1960), both tree age and apparent E were significant factors prior to the epidemic. During and following the epidemic, several of the more standard mensurational variables (e.g., diameter and basal area growth) were also significantly associated with balsam fir mortality, but apparent E had the highest levels of significance. Using logistical regression, critical E values below which trees would be predicted to die were calculated as 5-year running averages for the period prior to the epidemic (1960–1968). These were stable at around 0.17 × 10−4 m2 basal area growth•(m2 leaf area)−1•year−1. Following the epidemic, critical E values were again stable but at a lower level of around 0.07. There was a negative exponential relationship between apparent E and leaf area. Furthermore, for the same level of leaf area, surviving trees had a higher apparent E than trees that died, up to approximately 30 m2 of leaf area. These results suggest that growth efficiency should be considered as part of standard forest inventories in the balsam fir zone because of its ease of measure and its apparent ability to provide a sensitive, physiologically based index of forest health. Furthermore, the technique of historically reconstructing E demonstrated in this study may be of interest for other types of dendrochronological research.

Leaf area prediction models for Tsuga canadensis in Maine

1999 ◽  
Vol 29 (10) ◽  
pp. 1574-1582 ◽  
Author(s):  
Laura S Kenefic ◽  
Robert S Seymour
Keyword(s):  
Leaf Area ◽  
Prediction Models ◽  
Forest Type ◽  
Model Performance ◽  
Basal Area ◽  
Growth Efficiency ◽  
Tsuga Canadensis ◽  
Cross Sectional ◽  
Sapwood Area ◽  
Crown Length

Tsuga canadensis (L.) Carr. (eastern hemlock) is a common species throughout the Acadian forest. Studies of leaf area and growth efficiency in this forest type have been limited by the lack of equations to predict leaf area of this species. We found that sapwood area was an effective leaf area surrogate in T. canadensis, though adding crown length to the sapwood equations improved model performance. Prediction bias was observed at the upper end of our data for the best sapwood equation. Sapwood area at crown base did not predict leaf area as well as sapwood area at breast height. Equations using crown length or crown volume alone were the least effective of all models tested. Models using stem cross-sectional area inside the bark or tree basal area with a modified live crown ratio produced results comparable with those of the best sapwood-based model and were unbiased across the range of our data. There findings verify the value of nonsapwood-based approaches to T. canadensis leaf area prediction.

Pengaruh Likuiditas, Pertumbuhan Kredit, Efisiensi, dan Kecukupan Modal Terhadap Profitabilitas

2020 ◽  
Vol 1 (1) ◽  
pp. 27-35
Author(s):  
Lia Hendrawati ◽  
Said Djamaludin
Keyword(s):  
Stock Exchange ◽  
Growth Efficiency ◽  
Research Data ◽  
Capital Adequacy ◽  
Annual Data ◽  
Significant Positive Effect ◽  
Credit Growth ◽  
Negative Effect ◽  
Positive Effect ◽  
Observation Period

This study to examine and analyze the effect of liquidity, credit growth, efficiency, and capital adequacy on the Bank’s profitability listed on the IDX partially and simultaneously. The research data are annual data for the 5-year observation period (2009-2013). This research was conducted at 33 banks listed on Indonesia Stock Exchange. Banks Analyzed that met the population criteria were 23 banks. The analytical method used in multiple linier regression. The results showed that liquidity, credit growth, efficiency, and capital adequacy together (simultaneously) significantly influence profitability. Partially,  liquidity has a significant positive effect on profitability, while efficiency has a significant negative effect. Credit growth and capital adequacy have no significant effect on profitability. Liquidity is the variable that has the biggest effect on the Bank’s profitability. 

Response of aboveground biomass increment, growth efficiency, and foliar nutrients to thinning, fertilization, and pruning in young Douglas-fir plantations in the central Oregon Cascades

1992 ◽  
Vol 22 (9) ◽  
pp. 1278-1289 ◽  
Author(s):  
Alejandro Velazquez-Martinez ◽  
David A. Perry ◽  
Tom E. Bell
Keyword(s):  
Leaf Area ◽  
Aboveground Biomass ◽  
Cultural Practices ◽  
Growth Efficiency ◽  
Douglas Fir ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
Biomass Increment ◽  
Oregon Cascades

The effect of thinning and cultural practices (multinutrient fertilization, pruning) on total aboveground biomass increment and growth efficiency was studied over three consecutive 2-year periods (1981–1987) in young Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) plantations. Net aboveground biomass increment over the 6-year period averaged 14.5, 7.8, and 5.5 Mg•ha−1•year−1 for the high-, medium-, and low-density plots, respectively. Growth efficiency, after dropping sharply between leaf area indexes of 1 and 6 m2/m2, remained relatively constant up to a leaf area index of 17, the highest measured. Consequently, aboveground biomass increment continued to increase at leaf area indexes well above that at which the Beer–Lambert law predicts maximum light should be absorbed. Foliage analyses indicate that thinning improved nitrogen, potassium, and magnesium nutrition and increased the translocation of potassium from 1-year-old foliage to support new growth. However, fertilization increased foliar nitrogen and phosphorus contents only when coupled with pruning, suggesting that trees favor total leaf area over individual needle nutrition. Indications of potassium and magnesium limitations in this study are supported by other recent studies in Douglas-fir. Further work on the role of multinutrient deficiencies in this species is warranted.

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