Impact de la compétition exercée par le framboisier (Rubusidaeus L.) et les feuillus de lumière sur la croissance du sapin (Abiesbalsamea (L.) Mill.) en régénération

1992 ◽  
Vol 22 (9) ◽  
pp. 1408-1416 ◽  
Author(s):  
Jean-Claude Ruel
Keyword(s):  
Growth Parameters ◽  
Height Growth ◽  
Balsam Fir ◽  
Diameter Growth ◽  
Vegetation Density ◽  
Competing Vegetation ◽  
Relative Production ◽  
Relative Production Rate ◽  
The Impact ◽  
Competition Indices

This paper discusses the impact of competing vegetation on balsam fir (Abiesbalsamea (L.) Mill.) seedling growth. The study consisted of 12 permanent sample blocks of 0.5 ha. In each one, about 60 seedlings were selected to represent the various levels of competition. Ten competition indices were computed and compared for their relationship with balsam fir growth in height and diameter. Growth was slightly reduced by the competing vegetation but the relative production rate was not affected. An index using competing vegetation density and height relative to the seedling was selected for its simplicity and good correlation with the growth parameters. A simulation indicates that height growth for the next 5 years should remain correlated, although weakly, with the competing vegetation abundance. Balsam fir would be able to quickly overtop raspberry but would remain in the understory for some time when overtopped by hardwood light demanders.

Impact of tephra deposition on growth in conifers: the year of the eruption

1984 ◽  
Vol 14 (5) ◽  
pp. 731-739 ◽  
Author(s):  
Thomas M. Hinckley ◽  
Hiromi Imoto ◽  
Katharine Lee ◽  
Susan Lacker ◽  
Yasushi Morikawa ◽  
...  
Keyword(s):  
Fine Root ◽  
Height Growth ◽  
Diameter Growth ◽  
Growth Reduction ◽  
Root Mortality ◽  
Foliar Damage ◽  
Associated Species ◽  
The Impact ◽  
Total Tree ◽  
Mount St Helens

Seven sites ranging from 15 to 135 km from Mount St. Helens were selected to study the impact of air-fall tephra on the growth of Abiesamabilis (Dougl.) Forbes, A. procera Rehd., Pseudotsugamenziesii (Mirb.) Franco, Tsugaheterophylla (Raf.) Sarg., and T. mertensiana (Bong.) Carr. As tephra depth increased, there was a corresponding increase in visible foliar damage and associated decreases in diameter and height growth. Reduction in diameter growth was greater than reduction in height growth. The reduction in diameter growth approached 50% in both trees and saplings of A. amabilis. Growth reduction in true firs was greater than in associated species. This difference was related to their greater capacity for interception and retention of air-fall tephra. Damage to trees, and resulting growth reductions, were due to tephra coverage of both the foliage and the soil. Coverage of the foliage resulted in foliar damage, foliage abscission and reduction of total tree foliar area, and increased fine root mortality. Tephra coverage of the soil had the potential to restrict oxygen diffusion into the soil. However, soil oxygen concentrations less than 10% were measured only once over a 2-year period.

scholarly journals Influence of spacing and seed trees on the growth of Pericopsis elata saplings during the first twenty months of a planting trial

2021 ◽  
pp. 32-44
Author(s):  
Crispin Ilunga-Mulala ◽  
Hulda Hatakiwe ◽  
Hans Beeckman ◽  
Olivier J. Hardy ◽  
Gauthier Ligot ◽  
...  
Keyword(s):  
Generalized Additive Models ◽  
Economic Value ◽  
Natural Populations ◽  
Height Growth ◽  
Additive Models ◽  
Diameter Growth ◽  
Natural Forests ◽  
Maternal Origin ◽  
Sapling Growth ◽  
The Impact

Description of the subject. Pericopsis elata (Fabaceae) is a long-lived light-demanding tree from African rain forests that produces timber of high economic value. Natural populations suffer from overexploitation and a deficit of natural regeneration. Plantations could increase its production and limit the pressure on natural forests. However, we lack knowledge on the influence of spacing and seed tree origin on tree growth to optimize plantation protocols. Objectives. This study evaluated the impact of sapling density and seed tree origin on the growth in diameter and height of P. elata plants, 20 months after plantation. Method. Seeds were collected on 19 mother trees in a 400 ha natural stand near Kisangani (DRC). In October 2017, seedlings were transplanted in a Nelder design plantation with three replicates, to compare sapling growth at 10 contrasting plant densities under full sun. Diameter and height increments of 540 plants were analyzed according to local competition and maternal origin using generalized additive models. Results. Twenty months after planting, height growth peaked at an intermediate density of 47,000 stems·ha-1 (165.6 ± 39.2 cm·year-1), while diameter growth peaked at a lower density of 4,200 stems·ha-1 (24.6 ± 8.3 mm·year-1). The maternal origin of saplings affected their growth, the coefficients of variation among mother trees reaching 7.6% and 6.4% for diameter and height increments, respectively. The initial diameter affected positively diameter growth while the initial height did not influence height growth. Conclusions. The Nelder design proved useful to assess how plant growth depends both on spacing and genetic factors.

Impact of Pseudomonas putida on the Growth Parameters of Fenugreek (Trigonella foenum- graecum L.): A Traditional Herbal Boon for Rural Areas

2017 ◽  
Vol 5 (2) ◽  
pp. 93-96
Author(s):  
Shashi Kant Shukla ◽  
◽  
Awadhesh Kumar ◽  
Anupam Dikshit ◽  
◽  
...  
Keyword(s):  
Pseudomonas Putida ◽  
Rural Areas ◽  
Growth Parameters ◽  
Leguminous Plant ◽  
Food Protein ◽  
Botany Department ◽  
Medicinal Value ◽  
Randomized Design ◽  
Trigonella Foenum Graecum L ◽  
The Impact

The present study aims the impact of Pseudomonas putida on different growth parameters of Trigonella sp., a leguminous plant to support the requirement of food, protein along with their medicinal value in the rural areas of India. A pot experiment was arranged based on completely randomized design with four replications at Biological Product Laboratory, Botany Department, University of Allahabad. Treatments were given at the seed level with one of control. Results indicated that application of P. putida significantly improved vegetative growth and showed an edge on the growth of the fenugreek as compared to the control.

scholarly journals Aquatic Toxicity of Photocatalyst Nanoparticles to Green Microalgae Chlorella vulgaris

Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 77
Author(s):  
Cristina Adochite ◽  
Luminita Andronic
Keyword(s):  
Chlorella Vulgaris ◽  
Advanced Oxidation Process ◽  
Growth Parameters ◽  
Aquatic Toxicity ◽  
Basal Medium ◽  
Inhibitory Effect ◽  
Synthesis Methods ◽  
Potent Inhibitory Effect ◽  
Density Surface ◽  
The Impact

In the last years, nanoparticles such as TiO2, ZnO, NiO, CuO and Fe2O3 were mainly used in wastewater applications. In addition to the positive aspects concerning using nanoparticles in the advanced oxidation process of wastewater containing pollutants, the impact of these nanoparticles on the environment must also be investigated. The toxicity of nanoparticles is generally investigated by the nanomaterials’ effect on green algae, especially on Chlorella vulgaris. In this review, several aspects are reviewed: the Chlorella vulgaris culture monitoring and growth parameters, the effect of different nanoparticles on Chlorella vulgaris, the toxicity of photocatalyst nanoparticles, and the mechanism of photocatalyst during oxidative stress on the photosynthetic mechanism of Chlorella vulgaris. The Bold basal medium (BBM) is generally recognized as an excellent standard cultivation medium for Chlorella vulgaris in the known environmental conditions such as temperature in the range 20–30 °C and light intensity of around 150 μE·m2·s−1 under a 16/8 h light/dark cycle. The nanoparticles synthesis methods influence the particle size, morphology, density, surface area to generate growth inhibition and further algal deaths at the nanoparticle-dependent concentration. Moreover, the results revealed that nanoparticles caused a more potent inhibitory effect on microalgal growth and severely disrupted algal cells’ membranes.

scholarly journals Oil and Flower Production in Rosa damascena trigintipetala Dieck under Salinity Stress in Taif Region, Saudi Arabia

2021 ◽  
Vol 13 (8) ◽  
pp. 4547
Author(s):  
Mohamed E. El-Sharnouby ◽  
Metwally M. Montaser ◽  
Sliai M. Abdallah
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Salinity Stress ◽  
Growth Parameters ◽  
Industrial Applications ◽  
Rosa Damascena ◽  
Flower Production ◽  
Survival Percentage ◽  
The Impact ◽  
Tolerance To Salinity

The flower industry depends on oil and fragrance, which is addressed in the current work. Different concentrations of NaCl (0, 250, 500, 1000, and 1500 ppm) were applied to Taif rose plants (Rosa damascena var. trigintipetala Dieck) to evaluate their effects on growth and essential oil content. Results clearly indicated the highest survival percentage (98.3%) was seen in untreated plants compared to plants under salinity stress. Moreover, increasing the NaCl levels induced an adverse effect on the growth parameters of Taif rose plants, while some essential oil contents were increased to the maximum degree of their tolerance to salinity stress. The extracted essential oils were analyzed using GC/MS. The essential oils of Taif rose plants treated with 500 ppm NaCl recorded the highest values of citronellol, geraniol and phenylethyl alcohol contents (16.56, 8.67 and 9.87%), respectively. NaCl at 250 ppm produced the highest values of heneicosane (13.12%), and then decreased to the lowest value (7.79%) with the increase of NaCl to 1500 NaCl, compared to the control and other NaCl levels. The current results could highlight the impact of salinity stress on Rosa damascena Miller var. trigintipetala Dieck for better economic and industrial applications.

scholarly journals Pengaruh Magnesium, Boron, dan Pupuk Hayati terhadap Produktivitas Cabai serta Serangan Hama dan Penyakit (Effect of Magnesium, Boron, and Biofertilizers on Chili Pepper Productivity and Impact of Pests and Diseases)

2020 ◽  
Vol 30 (1) ◽  
pp. 65
Author(s):  
Wiwin Setiawati ◽  
Ahsol Hasyim ◽  
Bagus Kukuh Udiarto ◽  
Abdi Hudayya
Keyword(s):  
Yield Components ◽  
Growth Parameters ◽  
Block Design ◽  
Fruit Weight ◽  
Chili Pepper ◽  
Growth And Yield ◽  
Vegetable Crops ◽  
Positive Interaction ◽  
Pests And Diseases ◽  
The Impact

<p>Penggunaan pupuk hayati dan unsur hara makro sekunder seperti magnesium (Mg) dan hara mikro boron (B) diketahui dapat meningkatkan pertumbuhan, kualitas hasil tanaman, meningkatkan unsur hara dalam tanah serta mampu meningkatkan ketahanan tanaman terhadap serangan hama dan penyakit. Selain itu penggunaan pupuk tersebut dapat mengurangi kebutuhan terhadap pupuk kimia sintetis. Tujuan penelitian adalah mengetahui pengaruh aplikasi Mg, B, dan kombinasinya dengan pupuk hayati terhadap pertumbuhan dan hasil panen serta penekanan serangan hama dan penyakit. Penelitian dilakukan di Kebun Percobaan Balai Penelitian Tanaman Sayuran, Lembang, Jawa Barat (1.250 m dpl.) dari bulan Juni 2018 sampai bulan Februari 2019. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok terdiri atas delapan perlakuan dan empat ulangan. Perlakuan yang diuji adalah aplikasi Mg, B, dan kombinasi dengan pupuk hayati serta teknologi konvensional sebagai pembanding. Pengamatan dilakukan terhadap pertumbuhan tanaman (tinggi tanaman dan luas kanopi), komponen hasil dan hasil serta serangan hama dan penyakit penting yang menyerang tanaman cabai. Hasil penelitian menunjukkan bahwa kombinasi Mg, B, dan pupuk hayati yang diaplikasikan sebanyak dua kali pada umur 30 HST dan 45 HST mampu meningkatkan produktivitas cabai sebesar 21,68 ton/ha atau meningkat sebesar 54,53% dibandingkan dengan kontrol. Peningkatan produktivitas cabai terjadi karena adanya perbaikan dalam komponen hasil seperti jumlah bunga, jumlah buah, panjang, dan bobot buah serta adanya penekanan terhadap serangan hama dan penyakit seperti trips, antraknosa, lalat buah, dan penggerek buah sebesar 18,10% sampai 23,93%.</p><p><strong>Keywords</strong></p><p><em>Capsicum annuum</em>; Unsur hara makro; Pupuk hayati; Produktivitas; Organisme pengganggu tumbuhan</p><p><strong>Abstract</strong></p><p>The use of biofertilizer and macro and micro nutrients enhanced the growth and development, yield quality of vegetable crops as well as nutrient status of soil to a greater extent and to increased on pests and diseases resistance. Organic sources of nutrients including biofertilizers also economize the use of chemical fertilizers. The objectives of this study were to determine the best combination of Mg, B, and biofertilizer that increase the growth and yield of chili pepper and the impact to pest and diseases on chili pepper. The field experiment was conducted at the experimental field of the Indonesian Vegetable Research Institute, Lembang, West Java from June 2018 to February 2019. The experiment was arranged in a Randomized Block Design with eight treatments and four replicated. The treatments were Mg, B, and their combinations with biofertilizer compared to the conventional technologies as a control. The observations were carried out on the growth parameters (plant height and leaf canopy), yield components, pest and diseases of chili pepper. The results showed that the combinations of Mg, B, and biofertilizer increased the yield of chili up to 21.68 ton/ha or positive interaction beside beneficial agent with Mg, B, and biofertilizer package on 54.53%. Increased productivity of chili occurs because of improvements in yield components such as the number of flowers, number of fruits, fruit length and fruit weight and reduction of pest and disease attacks such as thrips, anthracnose, fruit flies and, fruit borers by 18.10% to 23.93%.</p>

scholarly journals The Influence of Regeneration Fellings on the Development of Artificially Regenerated Beech (Fagus sylvatica L.) Plantations

2014 ◽  
Vol 62 (5) ◽  
pp. 859-867
Author(s):  
Pavel Bednář ◽  
Jakub Černý
Keyword(s):  
Fagus Sylvatica ◽  
Height Growth ◽  
Diameter Growth ◽  
Quality Development ◽  
Statistical Tools ◽  
Total Height ◽  
Clear Cut ◽  
Spruce Stands ◽  
Fagus Sylvatica L

This paper analyses the development of beech plantations aged 7 to 18 years that were planted in gap cuts (0.1–0.25 ha; ISF 50%), clear cuts (0.5–1.0 ha; ISF 87%) and finally underplanted areas in shelterwood cuts in mature spruce stands (G = 22–26 m2/ha; ISF 28%). The research consisted of the following analyses: height growth, diameter growth and beech quality development. We used standard statistical tools (p < 0.05) for evaluating height and diameter growth, which showed significant differences in both characteristics (total height and DBH) within 7-year-old and 13-year-old plantations grown in all three regeneration treatments. The tallest beech trees with greatest DBH at the age of 7 and 13 were found in clearings whereas shortest and thinnest trees grew in shelterwoods. However, at the age of 18, there was no significant different between gap cut and clear cut in both parameters. The best quality was observed in shelterwoods.

scholarly journals Drought impacts on vegetation in the pre- and post-fire events over Iberian Peninsula

2012 ◽  
Vol 12 (10) ◽  
pp. 3123-3137 ◽  
Author(s):  
C. M. Gouveia ◽  
A. Bastos ◽  
R. M. Trigo ◽  
C. C. DaCamara
Keyword(s):  
Iberian Peninsula ◽  
Water Availability ◽  
Vegetation Dynamics ◽  
Early Summer ◽  
Fire Season ◽  
Drought Severity ◽  
Vegetation Density ◽  
Remotely Sensed Data ◽  
Recovery Times ◽  
The Impact

Abstract. The present work aims to study the combined effect of drought and large wildfires in the Iberian Peninsula relying on remotely sensed data of vegetation dynamics and leaf moisture content, in particular monthly NDVI, NDWI and NDDI time series from 1999–2009, derived from VEGETATION dataset. The impact of the exceptional 2004/2005 drought on vegetation was assessed for vegetation recovering from the extraordinary fire season of 2003 and on the conditions that contributed to the onsetting of the fire season of 2005. Drought severity was estimated by the cumulative negative effect on photosynthetic activity (NDVI) and vegetation dryness (NDDI), with about 2/3 of Iberian Peninsula presenting vegetative stress and low water availability conditions, in spring and early summer of 2005. Furthermore, NDDI has shown to be very useful to assess drought, since it combines information on vegetation and water conditions. Moreover, we show that besides looking at the inter-annual variability of NDVI and NDDI, it is useful to evaluate intra-annual changes (δNDVI and δNDDI), as indicators of change in vegetation greenness, allowing a detailed picture of the ability of the different land-cover types to resist to short-term dry conditions. In order to assess drought impact on post-fire regeneration, recovery times were evaluated by a mono-parametric model based on NDVI data and values corresponding to drought months were set to no value. Drought has shown to delay recovery times for several months in all the selected scars from 2003. The analysis of vegetation dynamics and fire selectivity in 2005 suggests that fires tended to occur in pixels presenting lower vegetative and water stress conditions during spring and early summer months. Additionally, pre-fire vegetation dynamics, in particular vegetation density and water availability during spring and early summer, has shown to influence significantly the levels of fire damage. These results stress the role of fuel availability in fire occurrence and impact on the Iberian Peninsula.

scholarly journals Impact of Wind Veer and the Coriolis Force for an Idealized Farm to Farm Interaction Case

2019 ◽  
Vol 9 (5) ◽  
pp. 922 ◽  
Author(s):  
Ola Eriksson ◽  
Simon-Philippe Breton ◽  
Karl Nilsson ◽  
Stefan Ivanell
Keyword(s):  
Coriolis Force ◽  
Wind Shear ◽  
Source Term ◽  
Wind Farms ◽  
Long Distance ◽  
Large Eddy ◽  
Relative Production ◽  
The Mean ◽  
The Right ◽  
The Impact

The impact of the Coriolis force on the long distance wake behind wind farms is investigated using Large Eddy Simulations (LES) combined with a Forced Boundary Layer (FBL) technique. When using the FBL technique any mean wind shear and turbulent fluctuations can be added with body forces. The wind shear can also include the mean wind veer due to the Coriolis force. The variation of the Coriolis force due to local deviations from the mean profile, e.g., from wakes, is not taken into account in the FBL. This can be corrected for with an extra source term in the equations, hereon defined as the Coriolis correction. For a row of 4 turbines it is shown that the inclusion of the wind veer turns the wake to the right, while including the Coriolis correction turns it to the left. When including both wind veer and Coriolis correction the impact of wind veer dominates. For an idealized farm to farm interaction case, two farms of 4 ∗ 4 turbines with 6 km in between, it can be seen that when including wind veer and the Coriolis correction a approximately 3% increase in the relative production for a full wake direction can be seen and only a slightly smaller increase can be seen when including only wind veer. The results indicate that FBL can be used for studies of long distance wakes without including a Coriolis correction but efforts need to be taken to use a wind shear with a correct mean wind veer.

scholarly journals Results of Czech ash provenance experiment

2017 ◽  
Vol 63 (No. 6) ◽  
pp. 263-274
Author(s):  
Buriánek Václav ◽  
Novotný Petr ◽  
Dostál Jaroslav
Keyword(s):  
Czech Republic ◽  
Growth Parameters ◽  
Stand Age ◽  
Diameter Growth ◽  
Site Conditions ◽  
Provenance Trial ◽  
The Czech Republic ◽  
Forest Regions

This study is focused on testing progenies of common and narrow-leaved ash based on the measurement of provenance trial plots established in various forest regions under different site conditions within the Czech Republic in the spring of 1999. Height and diameter growth of 35 provenances was measured and evaluated at the stand age of 10–14 years. The main goal of this research is to analyse and compare differences in growth between progenies originating from alluvial versus scree habitats as well as between the two evaluated ash species. Moreover, the influence of localities on growth was tested using standard provenances planted on all plots. The results of the last measurement were compared with those from the first survey in 2000 at the age of 4–5 years (1 year after planting). With the exception of DBH on the Koněprusy plot, statistically significant differences in height and diameter growth between provenances were verified. The results confirmed a very strong site influence on growth. The main conclusions indicate significant differences in growth parameters between provenances, faster growth of alluvial versus scree provenances on most lowland plots, and generally faster growth of narrow-leaved ash as compared to common ash.

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