Wood production and latewood percentage of Douglas-fir from different stands and vitality classes

1993 ◽  
Vol 23 (7) ◽  
pp. 1480-1486 ◽  
Author(s):  
Ingrid de Kort
Keyword(s):  
The Netherlands ◽  
Biomass Production ◽  
Douglas Fir ◽  
Total Biomass ◽  
Radial Increment ◽  
Small Decrease ◽  
Wood Biomass ◽  
Wood Production ◽  
Volume Increment ◽  
Needle Loss

Trunk wood production and amount of latewood of 171 Douglas-firs (Pseudotsugamenziesii (Mirb.) Franco) belonging to different vitality classes are analysed. The trees originated from 10 stands in the Netherlands varying in age from 25 to 70 years. Wood production is expressed as radial and volume increment over the last 15 years before sampling. The trees of 25–35 years old showed a better average vitality (less needle loss) than the older trees, and had a higher radial increment. Percentage of needle loss at the time of sampling was significantly and negatively correlated with radial and volume increment. The average latewood percentage over the last 15 years was the lowest in non vital trees. In non vital trees the wood-biomass production over the last 15 years was only ~30% of that in more vital trees. For the Netherlands as a whole the radial and volume increment in the last 15 years are estimated to be ~20% and ~4% lower, respectively, than they hypothetically would have been if all Douglas-firs belonged to the vitality classes 0 and 1. Total biomass production by Douglas-fir stands in the Netherlands is not greatly reduced by the small decrease in density in nonvital trees and is approximately 4% lower than if all trees were vital or slightly less vital.

Ring Width Patterns of Douglas Fir in Relation to Crown Vitality and Age

IAWA Journal ◽  
1997 ◽  
Vol 18 (1) ◽  
pp. 53-67 ◽  
Author(s):  
Ingrid de Kort ◽  
Pieter Baas
Keyword(s):  
The Netherlands ◽  
Growth Performance ◽  
Radial Growth ◽  
Forest Decline ◽  
Ring Width ◽  
Douglas Fir ◽  
Age Classes ◽  
Data Set ◽  
Needle Loss

Ring width patterns often different stands, five vitality classes and three age-classes are used to explore the effect of the decline in vitality on radial growth of Douglas fir in the Netherlands and to determine the onset of this decline. A relationship between growth performance and crown vitality is found in most stands, although the variation within and between stands is large. Severe needle loss leads to serious decline in ring width. The onset of the decline varies from c. 1959 to 1976. The present data set does not enable a choice between the various causal scenarios of forest decline that have been proposed in the literature.

Contrasting yield formation characteristics in two super-rice hybrids that differ in growth duration

2021 ◽  
pp. 1-10
Author(s):  
Min Huang ◽  
Zui Tao ◽  
Tao Lei ◽  
Fangbo Cao ◽  
Jiana Chen ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Biomass Production ◽  
Field Experiments ◽  
Crop Improvement ◽  
Total Biomass ◽  
Growth Duration ◽  
Area Index ◽  
Rice Hybrid ◽  
Use Efficiency ◽  
Yield Formation

Summary The development of high-yielding, short-duration super-rice hybrids is important for ensuring food security in China where multiple cropping is widely practiced and large-scale farming has gradually emerged. In this study, field experiments were conducted over 3 years to identify the yield formation characteristics in the shorter-duration (∼120 days) super-rice hybrid ‘Guiliangyou 2’ (G2) by comparing it with the longer-duration (∼130 days) super-rice hybrid ‘Y-liangyou 1’ (Y1). The results showed that G2 had a shorter pre-heading growth duration and consequently a shorter total growth duration compared to Y1. Compared to Y1, G2 had lower total biomass production that resulted from lower daily solar radiation, apparent radiation use efficiency (RUE), crop growth rate (CGR), and biomass production during the pre-heading period, but the grain yield was not significantly lower than that of Y1 because it was compensated for by the higher harvest index that resulted from slower leaf senescence (i.e., slower decline in leaf area index during the post-heading period) and higher RUE, CGR, and biomass production during the post-heading period. Our findings suggest that it is feasible to reduce the dependence of yield formation on growth duration to a certain extent in rice by increasing the use efficiency of solar radiation through crop improvement and also highlight the need for a greater fundamental understanding of the physiological processes involved in the higher use efficiency of solar radiation in super-rice hybrids.

Effects of mechanical stimulus, shade, and nitrogen fertilization on morphology and bending resistance in Douglas-fir seedlings

2003 ◽  
Vol 33 (9) ◽  
pp. 1602-1609 ◽  
Author(s):  
Stephen J Mitchell
Keyword(s):  
Nitrogen Fertilization ◽  
Mechanical Stimulus ◽  
Douglas Fir ◽  
Height Increment ◽  
Stem Form ◽  
Diameter Increment ◽  
Reduced Height ◽  
Bending Resistance ◽  
Volume Increment ◽  
Bending Stresses

Three-year-old coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in a factorial experiment with three levels of shading (0, 30, and 60%), three levels of mechanical stimulus (staked, freestanding, and bent), and two levels of nitrogen fertilization (0 and 200 kg/ha) to investigate the separate and combined effects of these factors on morphology and bending resistance. Fertilization increased branch angle and increased the sensitivity of branch and leader extension to bending stresses but did not affect volume increment, stem form, or bending resistance. The effects of shading and mechanical treatments on morphology were independent and additive. Shading reduced stem diameter and volume increment, but did not affect height increment, producing more slender trees. Bending produced less slender trees through a combination of reduced height increment and increased diameter increment. Staking did not affect tree morphology. Trees under heavy shade were responsive to bending but were more slender and had lower bending resistance than unshaded trees with the same mechanical stimulus. These results point towards the biological basis for the development of tree instability in high density stands.

Role of sink-source relationships in chrysanthemum flower size and total biomass production

2006 ◽  
Vol 128 (2) ◽  
pp. 263-273 ◽  
Author(s):  
Susana M.P. Carvalho ◽  
Ep Heuvelink ◽  
Jeremy Harbinson ◽  
Olaf Van Kooten
Keyword(s):  
Biomass Production ◽  
Flower Size ◽  
Total Biomass

Keepability of Pennsylvania versus West Coast Grown Douglas-Fir Christmas Trees: Genotypic Variation in Relation to Subfreezing Temperatures

1990 ◽  
Vol 7 (2) ◽  
pp. 86-89 ◽  
Author(s):  
Mark E. Kubiske ◽  
Marc D. Abrams ◽  
James C. Finley
Keyword(s):  
Pacific Northwest ◽  
Genotypic Variation ◽  
Rocky Mountain ◽  
Douglas Fir ◽  
Seed Sources ◽  
Christmas Trees ◽  
Display Area ◽  
The Pacific ◽  
Significant Difference ◽  
Needle Loss

Abstract Cut Douglas-fir Christmas trees grown in Pennsylvania from Rocky Mountain seed sources and coastal trees grown in the Pacific Northwest and shipped into Pennsylvania were compared for keepability. Following various cold treatments, the cut ends of trees were placed in water in an indoor display area. Coastal trees placed in a freezer at - 29°C for 24 h had 89 ± 5.1% (mean ± standard error) needle loss after one day of display, while Rocky Mountain origin trees exhibited only 3 ± 2.0% needle loss after 1 day and 50 ± 5.6% needle loss after 18 days. Coastal produced trees exposed to temperatures > - 12°C had 50 ± 9.8% needle loss at the end of the experiment, while Rocky Mountain trees ended with 22 ± 3.2% needle loss. Four additional treatments consisted of trees placed on an outdoor lot and periodically moved indoors to simulate Christmas tree market activity. Again, there was a significant difference between trees from coastal and Rocky Mountain sources, with 57.2 ± 4.3% and 11.8 ± 1.2% needle loss after 3 days, respectively. By the end of the 23 day experiment, the coastal trees were essentially devoid of needles, whereas Rocky Mountain trees had an average of only 20% needle loss. Coastal trees also exhibited a very noticeable loss of color and lustre. North. J. Appl. For. 7:86-89, June 1990.

scholarly journals Seeding Density and Nitrogen Fertilization Effects on Agronomic Responses of Some Hybrid Barley Lines in a Mediterranean Environment

Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1942
Author(s):  
Giovanni Preiti ◽  
Antonio Calvi ◽  
Maurizio Romeo ◽  
Giuseppe Badagliacca ◽  
Monica Bacchi
Keyword(s):  
Grain Yield ◽  
Biomass Production ◽  
Nitrogen Fertilization ◽  
Biogas Production ◽  
F1 Hybrids ◽  
Seeding Density ◽  
Total Biomass ◽  
Grain Production ◽  
Mediterranean Environment ◽  
Seeding Rate

Over two cropping seasons, 2017/18 and 2018/19, an experimental trial was conducted in a typical cereal-growing environment of the Calabrian hills (southern Italy) to study seeding rate (D) and nitrogen fertilization (N) effects on two barley F1 hybrids (Zoo and Jallon) compared to those of a traditional variety (Lutece), assessing the bio-agronomic response. Barley hybrids, gradually introduced into the principal European countries starting in 2010 as winter forage, currently represent a significant part of the EU internal market. Productive performance was evaluated as grain yield for feed and total biomass for silage and/or biogas production. Research results pointed out the greater performance of barley hybrids compared to conventional varieties in terms of both grain and biomass production. On average, barley hybrids vigour mainly manifested itself through a high tillering and a greater number of ears m−2 compared to those of the conventional variety (+24 and +23%, respectively). Furthermore, barley hybrids were characterized by a greater 1000-kernel weight and hectolitre weight than those of the Lutece variety (conventional variety). A significant increase in grain production was observed, increasing density from D150 to D225 rates (+35% and +33%, respectively) which was followed by a decrease in production shifting from D225 to D300 doses. A significant increase in biomass production was as well highlighted for the two hybrids, shifting from D150 to D225 rates (+26% and +27%, respectively). The applied nitrogen dose highlighted a different behaviour between the hybrids and the conventional variety; in particular, the lowest nitrogen dose (N80) negatively influenced the Lutece variety both in terms of grain and biomass production (−9% and −16%, respectively) while the hybrids showed the best agronomic response even at the lowest dose. On average, with the N80 dose, grain yield of Zoo and Jallon was greater than 20% and 16%, while with the N120 dose grain yield was 9% and 7%, respectively. A similar behaviour was found for biomass yield. It should therefore be emphasized that barley hybrids possess high yielding capacities and that such higher grain production can be achieved in a Mediterranean environment by using a lower seed rate (approximately −25%) and a reduced nitrogen dose (approximately −33%) compared with those commonly applied to conventional varieties.

scholarly journals Effects of water deficit on growth and physiology of young Conocarpus erectus L. and Ficus benjamina L. Saplings

2019 ◽  
Vol 48 (4) ◽  
pp. 1215-1221
Author(s):  
Zikria Zafar ◽  
Fahad Rasheed ◽  
Muhammad Abdullah ◽  
Mir Md Abdus Salam ◽  
Muhammad Mohsin
Keyword(s):  
Water Deficit ◽  
Biomass Production ◽  
Root Biomass ◽  
Growth Parameters ◽  
Co2 Assimilation ◽  
Total Biomass ◽  
Assimilation Rate ◽  
Ficus Benjamina ◽  
Co2 Assimilation Rate ◽  
Conocarpus Erectus

A greenhouse experiment was conducted to investigate the effects of water deficit on growth and physiological parameters of Ficus benjamina and Conocarpus erectus. The results revealed that all growth parameters such as plant height, stem diameter, no. of leaves, no. of branches and chlorophyll contents significantly decreased under water deficit condition. Interestingly, although leaf, stem and total biomass production and allocation decreased significantly under water deficit, but root biomass production and allocation increased significantly. Similarly, stomatal conductance to water vapor decreased significantly and CO2 assimilation rate remained similar to control under water deficit condition. Resultantly, a significant increase in water use efficiency was evident in both species under water deficit condition. These results suggested that, in spite of a significant decrease in biomass production, young Conocarpus erectus and Ficus benjamina can tolerate water deficit which is due to sustained CO2 assimilation rate and increase in root biomass.

scholarly journals Wetter is Better: Rewetting of Minerotrophic Peatlands Increases Plant Production and Moves Them Towards Carbon Sinks in a Dry Year

Ecosystems ◽  
2020 ◽  
Author(s):  
Sarah Schwieger ◽  
Juergen Kreyling ◽  
John Couwenberg ◽  
Marko Smiljanić ◽  
Robert Weigel ◽  
...  
Keyword(s):  
Organic Matter ◽  
Biomass Production ◽  
Plant Material ◽  
Carbon Sink ◽  
Belowground Biomass ◽  
Plant Production ◽  
Total Biomass ◽  
Carbon Sinks ◽  
Alder Forest ◽  
Organic Matter Accumulation

Abstract Peatlands are effective carbon sinks as more biomass is produced than decomposed under the prevalent anoxic conditions. Draining peatlands coupled with warming releases stored carbon, and subsequent rewetting may or may not restore the original carbon sink. Yet, patterns of plant production and decomposition in rewetted peatlands and how they compare to drained conditions remain largely unexplored. Here, we measured annual above- and belowground biomass production and decomposition in three different drained and rewetted peatland types: alder forest, percolation fen and coastal fen during an exceptionally dry year. We also used standard plant material to compare decomposition between the sites, regardless of the decomposability of the local plant material. Rewetted sites showed higher root and shoot production in the percolation fen and higher root production in the coastal fen, but similar root and leaf production in the alder forest. Decomposition rates were generally similar in drained and rewetted sites, only in the percolation fen and alder forest did aboveground litter decompose faster in the drained sites. The rewetted percolation fen and the two coastal sites had the highest projected potential for organic matter accumulation. Roots accounted for 23–66% of total biomass production, and belowground biomass, rather than aboveground biomass, was particularly important for organic matter accumulation in the coastal fens. This highlights the significance of roots as main peat-forming element in these graminoid-dominated fen peatlands and their crucial role in carbon cycling, and shows that high biomass production supported the peatlands’ function as carbon sink even during a dry year.

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