Changes in structural inequality in Norway spruce stands on peatland sites after water-level drawdown

Size structural dynamics of naturally established Norway spruce (Picea abies (L.) Karst.) stands growing on peatlands drained for forestry were investigated. The study was based on modelling of diameter at breast height (DBH) distributions of repeatedly measured stands in southern Finland. The Weibull function was used to parameterize the DBH distributions and mixed linear models were constructed to characterize the impacts of different ecological factors on stand dynamics. Initially, the positive skewness of the DBH distributions increased after drainage as a result of increases in stem numbers and a reduction in mean diameters. Simultaneously, the size inequality among trees increased. These changes were due to regeneration and (or) ingrowth and indicated only little competition from the larger trees. Subsequently, the DBH distributions changed from positively skewed to normal and finally to negatively skewed resulting from tree growth and a reduction in the number of small DBH trees. This indicated increased asymmetric intertree competition. Size inequality did not change during this later stage in stand development, suggesting a concurrent component of symmetric competition. Thinnings had little impact on DBH distribution trends. The observed stand dynamics allow the allocation of growth resources to the desired crop component by appropriate silvicultural treatments.

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Hmodel, a Heterobasidion annosum model for even-aged Norway spruce stands

Canadian Journal of Forest Research ◽

10.1139/cjfr-2014-0011 ◽

2014 ◽

Vol 44 (7) ◽

pp. 796-809 ◽

Cited By ~ 7

Author(s):

Juha Honkaniemi ◽

Risto Ojansuu ◽

Tuula Piri ◽

Risto Kasanen ◽

Mika Lehtonen ◽

...

Keyword(s):

Norway Spruce ◽

Root Rot ◽

Mycelial Growth ◽

Heterobasidion Annosum ◽

Stand Dynamics ◽

Northern Europe ◽

Tree Generation ◽

Spruce Stands ◽

Simulation Results ◽

Different Levels

Heterobasidion annosum (Fr.) Bref. s.l., a group of fungi causing root rot, is a serious threat to Norway spruce (Picea abies (L.) Karst.) stands in northern Europe. A new stochastic spatial model (Hmodel) was developed to simulate H. annosum s.l. infection and spread within a stand. Hmodel was combined with the stand-level decision support system MOTTI, resulting in a platform for estimating H. annosum s.l. development and its effect on tree growth and timber quality. Three H. annosum s.l. scenarios, representing different levels of risk for H. annosum s.l. infections simulated for a typical Norway spruce stand in southern Finland, demonstrated that the mycelial growth rate in the roots of living trees was the most critical parameter influencing the simulation results. In addition, the simulation results indicated that the number of infected trees in the previous stand plays a major role in H. annosum s.l. dynamics within the subsequent tree generation. Hmodel was designed to be a flexible platform for researchers to simulate the effects of H. annosum s.l. on stand dynamics and, vice versa, the effects of different silvicultural methods on H. annosum s.l. dynamics.

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Inheritance and Correlation Analysis of Main Agronomic Traits in Mungbean (Vigna radiata L.) by Mixed Linear Models

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2012.00624 ◽

2013 ◽

Vol 38 (4) ◽

pp. 624-631

Author(s):

Chang-You LIU ◽

Bao-Jie FAN ◽

Zhi-Min CAO ◽

Yan WANG ◽

Zhi-Xiao ZHANG ◽

...

Keyword(s):

Correlation Analysis ◽

Vigna Radiata ◽

Linear Models ◽

Agronomic Traits ◽

Mixed Linear Models

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Bucheckern-Voraussaat unter Fichtenschirm - Ergebnisse eines Versuchs des Deutschen Verbandes Forstlicher Forschungsanstalten/Sektion Waldbau -. Direct Seeding of European Beech (Fagus sylvatica L.) in Pure Norway Spruce Stands (Picea abies [L.] Karst.) - Results of an Experiment by the German Union of Forest Research Organizations/Silviculture Division -

Forftwiffenfchaftliches Centralblatt ◽

10.1046/j.1439-0337.2003.00160.x ◽

2003 ◽

Vol 122 (3) ◽

pp. 160-174 ◽

Cited By ~ 4

Author(s):

Bertram Leder ◽

Sven Wagner ◽

Jorg Wollmerstadt ◽

Christian Ammer

Keyword(s):

Picea Abies ◽

Norway Spruce ◽

Fagus Sylvatica ◽

European Beech ◽

Direct Seeding ◽

Forest Research ◽

Research Organizations ◽

Spruce Stands ◽

Fagus Sylvatica L

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Imitated Whole Tree Harvesting Show Negligible Effect on Economic Value of Spruce Stands

Forests ◽

10.3390/f12070841 ◽

2021 ◽

Vol 12 (7) ◽

pp. 841

Author(s):

Iveta Desaine ◽

Annija Kārkliņa ◽

Roberts Matisons ◽

Anna Pastare ◽

Andis Adamovičs ◽

...

Keyword(s):

Norway Spruce ◽

Economic Value ◽

Forest Types ◽

Spruce Stands ◽

The Difference ◽

Growing Conditions ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

The increased removal of forest-derived biomass with whole-tree harvesting (WTH) has raised concerns about the long-term productivity and sustainability of forest ecosystems. If true, this effect needs to be factored in the assessment of long-term feasibility to implement such a drastic forest management measure. Therefore, the economic performance of five experimental plantations in three different forest types, where in 1971 simulated WTH event occurred, was compared with pure, planted and conventionally managed (CH) Norway spruce stands of similar age and growing conditions. Potential incomes of CH and WTH stands were based on timber prices for period 2014–2020. However, regarding the economics of root and stump biomass utilization, they were not included in the estimates. In any given price level, the difference of internal rate of return between the forest types and selected managements were from 2.5% to 6.2%. Therefore, Norway spruce stands demonstrate good potential of independence regardless of stump removal at the previous rotation.

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A Novel Approach to Evaluate the Effect of Neighboring Trees and the Orientation of Tree Social Area on Stem Radial Increment of Norway Spruce Trees

Forests ◽

10.3390/f12020163 ◽

2021 ◽

Vol 12 (2) ◽

pp. 163

Author(s):

Jan Světlík ◽

Jan Krejza ◽

Pavel Bednář

Keyword(s):

Norway Spruce ◽

Tree Growth ◽

Growth Models ◽

Explanatory Power ◽

Radial Increment ◽

Important Indicator ◽

The Czech Republic ◽

Novel Approach ◽

Spruce Stands ◽

Social Area

Tree growth depends on many factors such as microsite conditions, vitality, and variations in climate and genetics. It is generally accepted that higher growth indicates both an economic benefit and better vitality of any tree. Here we use a modified approach of evaluating tree social area to study mutual tree competition based on the orientation and shape of trees social area. The investigation was performed in nine Norway spruce stands in the Czech Republic. The objective of this study performed from 2008 to 2012 was to quantify relative tree radial increments with respect to the lowest and highest competition found in specific sectors of tree social area (AS). Specific groups of trees (tree classes) were evaluated according to their classes (dominant, co-dominant and sub-dominant) and their composition status in ninety-degree sectors of AS using established classifying rules. The results showed that a spatially-available area (AA) is an inappropriate parameter for predicting tree growth, whereas AS provided robust explanatory power to predict relative radial growth. Tree size was observed as an important indicator of relative radial increments. A significantly positive correlation was found for a radial increment of sub-dominant trees with the lowest competition from western directions; whereas a negative correlation was observed when the lowest competition was observed from eastern directions. For dominant trees, there was an evident growth reaction only when more than 50% of the AS was oriented towards one of the cardinal points. Individual differences in the orientation of tree AS may be important parameters with regard to competition and its spatial variability within an area surrounding a particular tree and deserve more detailed attention in tree growth models and practice.

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