Branch growth and crown form in old coastal Douglas-fir

Ishiga, Hiroaki; Clement, Joel; Shaw, David C.

doi:10.1016/s0378-1127(99)00202-9

Cited by 39 publications

(29 citation statements)

References 19 publications

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“…Generally, it could be concluded that crown structure of trees develops as a result of the long-term interactions between tree ontogenesis, growth conditions and disturbances that cause defoliation, damage, dieback etc. (Ishii et al 2000). The decline of LAI could go in consequence of two phenomena: 1) decreasing density of live branches and the increasing density of dead branches (Ishii, Wilson 2001) and 2) decreasing production of needles and branches caused by low light, allocation of carbon and nitrogen following to reproductive onset (Thomas, Ickes 1995, Leal, Thomas 2003.…”

Section: Methodsmentioning

confidence: 99%

Leaf area index of Norway spruce stands in relation to age and defoliation

Pokorný

Stojnić

2012

Beskydy

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Pokorný R., Stojnič S. 2012: Leaf area index of Norway spruce stand in relation to its age and defoliation. -Beskydy, 5 (2): 173-180This contribution presents LAI data of 17 Norway spruce stands of different age (from 15 to 102 years) and health status (defoliation ranging from 0 to 40 %) located in the Těšínské Beskydy Mts. (NE of the Czech Republic). Defoliation degree was estimated by ocular observation and LAI was estimated indirectly on the base of gap fraction method using LAI-2000 PCA (Li-Cor, USA). It was found that LAI decreased with stand age (approximately from 12.6 to 8.5) whereas defoliation increased. Therefore, strong relationship between defoliation and LAI as well as gap fractions was found. LAI appears valuable parameter for health status of stand evaluation due to linear relationship (r 2 = 0.87) between LAI and defoliation. As LAI can be estimated more objectively by a canopy analyzer then the degree of canopy defoliation by ocular observation, there is a perspective for a wide use LAI in forest practice. The LAI values can be used for the evaluation of health status of Norway spruce stands.

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Section: Methodsmentioning

confidence: 99%

Leaf area index of Norway spruce stands in relation to age and defoliation

Pokorný

Stojnić

2012

Beskydy

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“…[8,25,26,29,35]). However, these equations require many parameters that are not directly measurable (e.g.…”

Section: Estimation Of Crown Dimensions 395mentioning

confidence: 99%

Estimation of crown radii and crown projection area from stem size and tree position

Grote

2003

Ann. For. Sci.

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-This paper describes a method for crown radii estimation in different cardinal directions using tree diameter, height, crown length, and stem position within the stand as independent variables. The approach can serve for the initialisation of crown dimensions if measured crown radii are not available in order to address various research questions. Test calculations are carried out with 4 pure spruce (Picea abies L. Karst), 5 beech (Fagus sylvatica L.), and 6 mixed stands with both species. Simulated tree radii, crown projection area and canopy cover are compared with measurements and simple estimation procedures based on logarithmic and linear equations. In beech stands and dense spruce stands the estimates with the new approach are similar or superior to those obtained with the other methods. However, in sparse plots or in stands, which have experienced a recent thinning crown size of trees is overestimated.crown projection area / crown radii / Fagus sylvatica / mixed forests / Picea abies Résumé -Estimation des rayons et de la zone de projection de la couronne en utilisant les dimensions de la tige et la position de l'arbre. Cet article introduit une méthode mathématique qui permet une estimation du rayon, en utilisant seulement les dimensions de la tige de la couronne et la position de l'arbre. Cette méthode permet d'initialiser les dimensions de la couronne dans le cas où on ne connaît pas les rayons pour ainsi traiter de différentes questions scientifiques. La méthode est testée sur de nombreux peuplements d' épicéas (Picea abies) et de hêtres (Fagus sylvatica), non seulement constitués d'une seule essence mais aussi de forêts mixtes, dans le sud de l'Allemagne. Les simulations du rayon des couronnes, de la surface de projection d'une couronne et du degré de couverture sont comparées avec des mesures et d'autres estimations basées sur des équations linéaires ou logarithmiques. Les résultats montrent que la nouvelle méthode est appropriée pour la représentation des rayons des couronnes de hêtres et pour des peuplements denses d'épicéa. En revanche le rayon et la surface de la couronne d'arbres ayant poussé dans des lieux clairsemés ou ayant subi une éclaircie sont surestimés.projection des couronnes / rayons des couronnes / Fagus sylvatica / forêts mixtes / Picea abies

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“…Therefore, the inverse of the mean life span of foliage is not an appropriate estimate for needle turnover in terms of biomass (Muukkonen 2005). The life span, death and growth patterns of branches were examined to maximize wood quality (Kellomäki and Tuimala 1981, Madgwick et al 1986, Kellomäki and Väisanen 1988, Maguire 1994, Mäkinen 1999, Mäkinen and Colin 1999, Ishii et al 2000, Mäkinen et al 2002, Mäkela and Mäkinen 2003, Mäkinen et al 2003. However, very little is known of the litterfall of large branches, except for the few studies that have proposed alternative approaches, such as branch mortality dating by Maguire (1994).…”

Section: Methods To Assess Carbon Flows Of Forestsmentioning

confidence: 99%

Carbon stocks and flows in forest ecosystems based on forest inventory data

Lehtonen¹

2005

Diss. For.

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Countries are currently reporting changes in carbon pools of forests to UNFCCC. According to the reporting guidelines methods should be transparent and verifiable, and also the quantification of the uncertainty is asked.The objective of the thesis was to develop methods for quantifying carbon stocks and fluxes at national scale based on forest inventory data.To estimate tree biomass of forests, representative BEFs (biomass expansion factors) with uncertainty estimate were developed for Finland. A method for quantifying carbon flux of branches to soil was also developed. Both biomass and branch litterfall estimates were tested against independent measurements. Biomass estimation method and litterfall estimates were applied with Finnish forest inventory data to estimate carbon stocks and their changes for Finnish forests for . In this application main sources of litter were quantified based on forest inventory data and fed into dynamic soil decomposition model in order to estimate soil carbon stocks and its changes.Application of BEFs, litterfall estimates and soil model gave time series of carbon stocks in Finnish forests. Results showed that tree carbon stock of Finland increased from 510 Tg to 780 Tg, while carbon in mineral soils increased from 850 Tg to 960 Tg during 80 year period. It was also found that there were high inter annual variation with soil-and tree carbon stocks caused by harvestings and temperature. According to the results, the NPP (net primary production) of Finnish forests has increased from 0.3 to 0.4 kg m -2 during studied period, while NBP (net biome production) was positive since 1970s.Results emphasize the importance of complete counting of changes of forest carbon pools i.e., trees, litter, soil and dead wood. Completeness will be important especially if forest management is used as a tool to mitigate climate change by enhancing carbon sinks of forests.

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Branch growth and crown form in old coastal Douglas-fir

Cited by 39 publications

References 19 publications

Leaf area index of Norway spruce stands in relation to age and defoliation

Leaf area index of Norway spruce stands in relation to age and defoliation

Estimation of crown radii and crown projection area from stem size and tree position

Carbon stocks and flows in forest ecosystems based on forest inventory data

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