Shedding of older needle age classes does not necessarily reduce photosynthetic primary production of Norway spruce

Trees ◽  
1994 ◽  
Vol 9 (1) ◽  
Author(s):  
Wolfram Beyschlag ◽  
RonaldJ. Ryel ◽  
Christian Dietsch
Keyword(s):  
Primary Production ◽  
Norway Spruce ◽  
Age Classes ◽  
Needle Age

Relation between leaf biomass and annual ring sapwood of Norway spruce according to needle age-class

1996 ◽  
Vol 26 (10) ◽  
pp. 1822-1827 ◽  
Author(s):  
Vitezslav Dvorak ◽  
Magda Oplustilova ◽  
Dalibor Janous
Keyword(s):  
Norway Spruce ◽  
Coefficient Of Determination ◽  
Leaf Biomass ◽  
Age Classes ◽  
Sapwood Area ◽  
Needle Age ◽  
Mean Values ◽  
Pipe Model ◽  
The Mean ◽  
The Relationship

The relationship between leaf biomass and sapwood area was investigated in a 35-year-old Norway spruce (Piceaabies (L.) Karst.) stand in mountainous conditions. Fifteen trees were destructively sampled to determine the needle biomass in several needle age-classes and whorls and the corresponding sapwood areas at the whorl branch bases and in stems at breast height. Leaf biomass/sapwood area ratio and specific leaf biomass (g•mm−2) were calculated for different needle age-classes and also for different positions in the vertical profile of the crown. The leaf biomass/sapwood area ratios were described by linear regression with a high coefficient of determination. Specific leaf biomass analysed in whorl branches was highest in the upper whorls but was decreasing downward through the profile; remained stable in the middle crown layer; and decreased again in the lower crown parts. Specific leaf biomass assessments for stems showed the largest and most increasing values in the youngest three needle age-classes followed by a decreasing trend of the specific leaf biomass in older needle age-classes. The mean values of specific leaf biomass were 1.08 g•mm−2 for branches and 1.02 g•mm−2 for stems. The results of our study are consistent with the "pipe model theory."

scholarly journals The concentration of Ca, Sr, Ba and Mn in successive needle age classes of Norway spruce [Picea abies (L.) Karst.]

Trees ◽  
1995 ◽  
Vol 10 (1) ◽  
Author(s):  
Armin Wyttenbach ◽  
Sixto Bajo ◽  
J�rg Bucher ◽  
Verena Furrer ◽  
Patrick Schleppi ◽  
...  
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Age Classes ◽  
Needle Age

scholarly journals Allometric relationships for surface area and dry mass of young Norway spruce aboveground organs

2008 ◽  
Vol 53 (No. 12) ◽  
pp. 548-554 ◽  
Author(s):  
R. Pokorný ◽  
I. Tomášková
Keyword(s):  
Surface Area ◽  
Norway Spruce ◽  
Tree Height ◽  
Dry Mass ◽  
Tree Level ◽  
Stem Volume ◽  
Age Classes ◽  
Sapwood Area ◽  
Needle Age ◽  
Leaf Mass

Tree-level allometric functions for a precise predicting of stem, branch and leaf mass and surface area of three needle-shoot age classes were estimated from measurements of crown and stem dimensions in 34 harvested Norway spruce (<I>Picea abies</I> [L.] Karst.) trees. Trees were grown within a 16-years-old stand in the Beskids Mountains. The results showed stem parameters (stem diameter at breast height – dbh, stem volume – Vs and stem sapwood area – SA) to be highly correlated (<I>r</I> > 0.98) with stem mass/area and total aboveground mass of tree. Crown parameters – volume (Cv) and surface area (Ca) were the best predictors for individual branch and needle age-classes mass (<I>r</I> > 0.92) or area (<I>r</I> > 0.85), specifically for mass and surface areas of young branches and needles. dbh most correctly predicted the branch and leaf mass/surface area of older (> 2 years) shoots. The measured parameters: dbh, SA, tree height, crown length, Ca and Cv showed a high dependence on the tree position within the stand (<I>r</I> > –0.81). Thus, these parameters could be modified by silviculture.

The accumulation of the rare earth elements and of scandium in successive needle age classes of Norway spruce

1994 ◽  
Vol 41 (1-2) ◽  
pp. 13-29 ◽  
Author(s):  
Armin Wyttenbach ◽  
Patrik Schleppi ◽  
Jürg Bucher ◽  
Verena Furrer ◽  
Leonhard Tobler
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Norway Spruce ◽  
Age Classes ◽  
Needle Age ◽  
The Rare Earth

scholarly journals Foliage Biophysical Trait Prediction from Laboratory Spectra in Norway Spruce Is More Affected by Needle Age Than by Site Soil Conditions

2021 ◽  
Vol 13 (3) ◽  
pp. 391 ◽  
Author(s):  
Zuzana Lhotáková ◽  
Veronika Kopačková-Strnadová ◽  
Filip Oulehle ◽  
Lucie Homolová ◽  
Eva Neuwirthová ◽  
...  
Keyword(s):  
Soil Properties ◽  
Norway Spruce ◽  
Partial Least Square ◽  
Soil Conditions ◽  
Leaf Mass Per Area ◽  
Age Classes ◽  
Needle Age ◽  
Leaf Mass ◽  
Leaf Level ◽  
Trait Prediction

Scaling leaf-level optical signals to the canopy level is essential for airborne and satellite-based forest monitoring. In evergreen trees, biophysical and optical traits may change as foliage ages. This study aims to evaluate the effect of age in Norway spruce needle on biophysical trait-prediction based on laboratory leaf-level spectra. Mature Norway spruce trees were sampled at forest stands in ten headwater catchments with different soil properties. Foliage biophysical traits (pigments, phenolics, lignin, cellulose, leaf mass per area, water, and nitrogen content) were assessed for three needle-age classes. Complementary samples for needle reflectance and transmittance were measured using an integrating sphere. Partial least square regression (PLSR) models were constructed for predicting needle biophysical traits from reflectance—separating needle age classes and assessing all age classes together. The ten study sites differed in soil properties rather than in needle biophysical traits. Optical properties consistently varied among age classes; however, variation related to the soil conditions was less pronounced. The predictive power of PLSR models was needle-age dependent for all studied traits. The following traits were predicted with moderate accuracy: needle pigments, phenolics, leaf mass per area and water content. PLSR models always performed better if all needle age classes were included (rather than individual age classes separately). This also applied to needle-age independent traits (water and lignin). Thus, we recommend including not only current but also older needle traits as a ground truth for evergreen conifers with long needle lifespan.

scholarly journals Canopy Top, Height and Photosynthetic Pigment Estimation Using Parrot Sequoia Multispectral Imagery and the Unmanned Aerial Vehicle (UAV): Norway Spruce Forest Case Study

2021 ◽  
Author(s):  
Veronika Kopačková-Strnadová ◽  
Lucie Koucká ◽  
Jan Jelenek ◽  
Zuzana Lhotakova ◽  
Filip Oulehle
Keyword(s):  
Norway Spruce ◽  
Unmanned Aerial Vehicle ◽  
Linear Models ◽  
Photosynthetic Pigment ◽  
Ground Truth ◽  
Needle Age ◽  
Vegetation Indexes ◽  
Pigment Contents ◽  
Aerial Vehicle ◽  
Uav Images

Remote sensing is one of the modern methods that have significantly developed over the last two decades and nowadays provides a new means for forest monitoring. High spatial and temporal resolutions are demanded for accurate and timely monitoring of forests. In this study multi-spectral Unmanned Aerial Vehicle (UAV) images were used to estimate canopy parameters (definition of crown extent, top and height as well as photosynthetic pigment contents). The UAV images in Green, Red, Red-Edge and NIR bands were acquired by Parrot Sequoia camera over selected sites in two small catchments (Czech Republic) covered dominantly by Norway spruce monocultures. Individual tree extents, together with tree tops and heights, were derived from the Canopy Height Model (CHM). In addition, the following were tested i) to what extent can the linear relationship be established between selected vegetation indexes (NDVI and NDVIred edge) derived for individual trees and the corresponding ground truth (e.g., biochemically assessed needle photosynthetic pigment contents), and ii) whether needle age selection as a ground truth and crown light conditions affect the validity of linear models. The results of the conducted statistical analysis show that the two vegetation indexes (NDVI and NDVIred edge) tested here have a potential to assess photosynthetic pigments in Norway spruce forests at a semi-quantitative level, however the needle-age selection as a ground truth was revealed to be a very important factor. The only usable results were obtained for linear models when using the 2nd year needle pigment contents as a ground truth. On the other hand, the illumination conditions of the crown proved to have very little effect on the model&rsquo;s validity. No study was found to directly compare these results conducted on coniferous forest stands. This shows that there is a further need for studies dealing with a quantitative estimation of the biochemical variables of nature coniferous forests when employing spectral data acquired by the UAV platform at a very high spatial resolution.

Mismatch between the optimal ages for ecosystem productivity and net CO2 sequestration in Norway spruce forests

2021 ◽  
Author(s):  
Junbin Zhao ◽  
Holger Lange ◽  
Helge Meissner
Keyword(s):  
Climate Change ◽  
Primary Production ◽  
Norway Spruce ◽  
Ecosystem Respiration ◽  
Gross Primary Production ◽  
Economic Benefits ◽  
Sink Strength ◽  
Climate Change Scenarios ◽  
Ecosystem Productivity ◽  
Spruce Forests

&lt;p&gt;Forests have climate change mitigation potential since they sequester carbon. However, their carbon sink strength might depend on management. As a result of the balance between CO&lt;sub&gt;2&lt;/sub&gt; uptake and emission, forest net ecosystem exchange (NEE) reaches optimal values (maximum sink strength) at young stand ages, followed by a gradual NEE decline over many years. Traditionally, this peak of NEE is believed to be concurrent with the peak of primary production (e.g., gross primary production, GPP); however, in theory, this concurrence may potentially vary depending on tree species, site conditions and the patterns of ecosystem respiration (R&lt;sub&gt;eco&lt;/sub&gt;). In this study, we used eddy-covariance (EC)-based CO&lt;sub&gt;2&lt;/sub&gt; flux measurements from 8 forest sites that are dominated by Norway spruce (Picea abies L.) and built machine learning models to find the optimal age of ecosystem productivity and that of CO&lt;sub&gt;2&lt;/sub&gt; sequestration. We found that the net CO&lt;sub&gt;2&lt;/sub&gt; uptake of Norway spruce forests peaked at ages of 30-40 yrs. Surprisingly, this NEE peak did not overlap with the peak of GPP, which appeared later at ages of 60-90 yrs. The mismatch between NEE and GPP was a result of the R&lt;sub&gt;eco&lt;/sub&gt; increase that lagged behind the GPP increase associated with the tree growth at early age. Moreover, we also found that newly planted Norway spruce stands had a high probability (up to 90%) of being a C source in the first year, while, at an age as young as 5 yrs, they were likely to be a sink already. Further, using common climate change scenarios, our model results suggest that net CO&lt;sub&gt;2&lt;/sub&gt; uptake of Norway spruce forests will increase under the future climate with young stands in the high latitude areas being more beneficial. Overall, the results suggest that forest management practices should consider NEE and forest productivity separately and harvests should be performed only after the optimal ages of both the CO&lt;sub&gt;2&lt;/sub&gt; sequestration and productivity to gain full ecological and economic benefits.&lt;/p&gt;

Sign in / Sign up

Export Citation Format

Share Document