Sprouting ability of aerial and underground dormant basal buds of Betulapendula

1991 ◽  
Vol 21 (4) ◽  
pp. 528-533 ◽  
Author(s):  
A. Kauppi ◽  
K. Paukkonen ◽  
P. Rinne
Keyword(s):  
Environmental Factors ◽  
Ground Level ◽  
Silver Birch ◽  
Intact Plants ◽  
Sprouting Ability ◽  
Internal Condition ◽  
Uncovered Part ◽  
Pot Plants

The effect of ground level on the bursting and development of primary basal buds, formation of secondary basal buds, and survival of sprouts was studied with 2-year-old pot plants of silver birch (Betulapendula Roth) in an experiment in which the ground level was changed. Both intact and decapitated seedlings were manipulated. Raising the ground level reduced the bursting of dormant basal buds, while lowering it promoted both the bursting of buds and survival of the sprouts, especially in the decapitated plants. Many new basal buds developed regardless of the ground level. The intact plants also formed secondary basal buds, but these mostly remained dormant, like old, primary buds. In addition, the concentration of new bud clusters in the uncovered part of the stem suggested that although the plant's internal condition is important for the development and bursting of its basal buds, environmental factors are also involved. Ground-level changes on drained mires and at afforestation sites may significantly affect the success of sprouting.

scholarly journals Wildfire Detection Probability of MODIS Fire Products under the Constraint of Environmental Factors: A Study Based on Confirmed Ground Wildfire Records

2019 ◽  
Vol 11 (24) ◽  
pp. 3031 ◽  
Author(s):  
Lingxiao Ying ◽  
Zehao Shen ◽  
Mingzheng Yang ◽  
Shilong Piao
Keyword(s):  
Environmental Factors ◽  
Detection Probability ◽  
Ground Level ◽  
Omission Error ◽  
Limiting Factor ◽  
Commission Error ◽  
Fire Size ◽  
Weather Factors ◽  
Local Conditions ◽  
Wildfire Occurrence

The Moderate Resolution Imaging Spectroradiometer (MODIS) has been widely used for wildfire occurrence and distribution detecting and fire risk assessments. Compared with its commission error, the omission error of MODIS wildfire detection has been revealed as a much more challenging, unsolved issue, and ground-level environmental factors influencing the detection capacity are also variable. This study compared the multiple MODIS fire products and the records of ground wildfire investigations during December 2002–November 2015 in Yunnan Province, Southwest China, in an attempt to reveal the difference in the spatiotemporal patterns of regional wildfire detected by the two approaches, to estimate the omission error of MODIS fire products based on confirmed ground wildfire records, and to explore how instantaneous and local environmental factors influenced the wildfire detection probability of MODIS. The results indicated that across the province, the total number of wildfire events recorded by MODIS was at least twice as many as that in the ground records, while the wildfire distribution patterns revealed by the two approaches were inconsistent. For the 5145 confirmed ground records, however, only 11.10% of them could be detected using multiple MODIS fire products (i.e., MOD14A1, MYD14A1, and MCD64A1). Opposing trends during the studied period were found between the yearly occurrence of ground-based wildfire records and the corresponding proportion detected by MODIS. Moreover, the wildfire detection proportion by MODIS was 11.36% in forest, 9.58% in shrubs, and 5.56% in grassland, respectively. Random forest modeling suggested that fire size was a primary limiting factor for MODIS fire detecting capacity, where a small fire size could likely result in MODIS omission errors at a threshold of 1 ha, while MODIS had a 50% probability of detecting a wildfire whose size was at least 18 ha. Aside from fire size, the wildfire detection probability of MODIS was also markedly influenced by weather factors, especially the daily relative humidity and the daily wind speed, and the altitude of wildfire occurrence. Considering the environmental factors’ contribution to the omission error in MODIS wildfire detection, we emphasized the importance of attention to the local conditions as well as ground inspection in practical wildfire monitoring and management and global wildfire simulations.

scholarly journals Using wearable devices for assessing the impacts of hair exposome in Brazil

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Rodrigo De Vecchi ◽  
Júlia da Silveira Carvalho Ripper ◽  
Daniel Roy ◽  
Lionel Breton ◽  
Alexandre Germano Marciano ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Urban Areas ◽  
Sun Exposure ◽  
Ground Level ◽  
Wearable Devices ◽  
Climate Conditions ◽  
Multiple Sensors ◽  
Underlying Mechanisms ◽  
New Research ◽  
The Impact

Abstract Previous studies have shown that physicochemical properties of hair can be impacted by internal and environmental exposures ranging from chemical stressors to weather. Besides the effects on hair, these exposures, termed “exposome”, can act on specific organs including skin, as a synergistic damaging effect of UV exposure and pollution on human surfaces. The combination of several environmental factors such as sun exposure, temperature, relative humidity, air pollution and photo-oxidation caused by ground level ozone impacts hair properties such as melanin oxidation, protein content, surface quality and structural components. Therefore, exposome studies can reveal new hypotheses on how epithelia and hair could be affected by daily life environment and routine. The aim of this study was to evaluate the impact of several environmental aggressors on human surfaces, using portable and wearable devices for monitoring exposome. To better understand the underlying mechanisms associated with environmental factors, two subjects wore multiple sensors to capture the meteorological conditions biking through urban areas in summer and winter. Temperature, humidity, UV radiation and ozone concentration were recorded and hair swatches of different types, including natural, bleached/colored, colored and gray, were exposed on the helmets. Silicon wristbands were used on skin to identify main chemical aggressors. After exposure, hair swatches were analyzed by surface microscopy analysis, oxidation markers and more than 1,500 chemicals were evaluated on the bracelets. Correlated with GPS and monitoring data, all these results provide insights on how environmental stressors affect the quality of different hair types and body surface according to exposure routine. Our results suggest extreme climate conditions associated with hair damage and photo-oxidative marker linked to the environmental aggressors. Polycyclic aromatic hydrocarbons (PAH) indicate possible causes of hair damages. This is the first meteorotropic study of its kind, combining environmental aggressors related to hair damage, opening new research hypothesis further studies on exposome.

Wildfire Detection Probability of MODIS Fire Products under the Constraint of Environmental Factors: A Study Based on Confirmed Ground Wildfire Records

2020 ◽  
Author(s):  
Lingxiao Ying ◽  
Zehao Shen ◽  
Mingzheng Yang ◽  
Shilong Piao
Keyword(s):  
Environmental Factors ◽  
Detection Probability ◽  
Ground Level ◽  
Omission Error ◽  
Limiting Factor ◽  
Commission Error ◽  
Fire Size ◽  
Weather Factors ◽  
Local Conditions ◽  
Wildfire Occurrence

<p>The Moderate Resolution Imaging Spectroradiometer (MODIS) has been widely used for wildfire occurrence and distribution detecting and fire risk assessments. Compared with its commission error, the omission error of MODIS wildfire detection has been revealed as a much more challenging, unsolved issue, and ground-level environmental factors influencing the detection capacity are also variable. This study compared the multiple MODIS fire products and the records of ground wildfire investigations during December 2002–November 2015 in Yunnan Province, Southwest China, in an attempt to reveal the difference in the spatiotemporal patterns of regional wildfire detected by the two approaches, to estimate the omission error of MODIS fire products based on confirmed ground wildfire records, and to explore how instantaneous and local environmental factors influenced the wildfire detection probability of MODIS. The results indicated that across the province, the total number of wildfire events recorded by MODIS was at least twice as many as that in the ground records, while the wildfire distribution patterns revealed by the two approaches were inconsistent. For the 5145 confirmed ground records, however, only 11.10% of them could be detected using multiple MODIS fire products (i.e., MOD14A1, MYD14A1, and MCD64A1). Opposing trends during the studied period were found between the yearly occurrence of ground-based wildfire records and the corresponding proportion detected by MODIS. Moreover, the wildfire detection proportion by MODIS was 11.36% in forest, 9.58% in shrubs, and 5.56% in grassland, respectively. Random forest modeling suggested that fire size was a primary limiting factor for MODIS fire detecting capacity, where a small fire size could likely result in MODIS omission errors at a threshold of 1 ha, while MODIS had a 50% probability of detecting a wildfire whose size was at least 18 ha. Aside from fire size, the wildfire detection probability of MODIS was also markedly influenced by weather factors, especially the daily relative humidity and the daily wind speed, and the altitude of wildfire occurrence. Considering the environmental factors’ contribution to the omission error in MODIS wildfire detection, we emphasized the importance of attention to the local conditions as well as ground inspection in practical wildfire monitoring and management and global wildfire simulations.</p>

Sprouting ability of advance growth in undisturbed hardwood stands

1979 ◽  
Vol 9 (1) ◽  
pp. 116-120 ◽  
Author(s):  
Douglas S. Powell ◽  
E. H. Tryon
Keyword(s):  
Sugar Maple ◽  
Ground Level ◽  
Northern Red Oak ◽  
Red Maple ◽  
White Oak ◽  
High Quality ◽  
White Ash ◽  
Good Ability ◽  
Sprouting Ability ◽  
Mature Stands

We studied eight species of hardwoods to evaluate their ability to produce seedling sprouts (trees with stems that sprouted from a stump less than 2 in. (5 cm) in diameter at ground level) in the advance growth of undisturbed, mature stands on high-quality upland sites in West Virginia. The most reliable criterion used to measure this ability was the percentage of seedling sprouts, which indicated relatively good ability for white oak and black cherry; intermediate ability for dogwood, hickory, and white ash; and relatively poor ability for red maple, northern red oak, and sugar maple. Since the two oaks were at opposite ends of the spectrum, the results suggest that factors other than the ability to produce seedling sprouts may explain the growth of virtually pure oak stands on high-quality sites.

scholarly journals Foraging pattern and harvesting of resources of subterranean stingless bee Geotrigona subterranea (Friese, 1901) (Hymenoptera: Apidae: Meliponini)

2016 ◽  
Vol 56 (12) ◽  
pp. 151 ◽  
Author(s):  
Fernando Mendes Barbosa ◽  
Lúcio Antônio De Oliveira Campos ◽  
Joana Fidelis da Paixão ◽  
Rogério Marcos De Oliveira Alves
Keyword(s):  
Environmental Factors ◽  
Natural Environment ◽  
Minas Gerais ◽  
Stingless Bee ◽  
Flight Activity ◽  
External Factors ◽  
Tree Cavities ◽  
Minas Gerais State ◽  
Internal Condition ◽  
Foraging Pattern

Flight activity of bees is influenced both by environmental factors and by internal condition of the colonies. Information about external activity of bees is very important, because it provides data of the species biology, supplying subsidies for the use of these insects in the pollination of crops. The present work aim to evaluate the flight activity of Geotrigona subterranea (Friese, 1901) (Hymenoptera: Apidae) in natural environment. This study was performed on the Instituto Federal do Norte de Minas Gerais, in the municipality Januária, Minas Gerais State. Two natural nests were observed. The activities of bees of the colonies were recorded three days each month, during the period of December 2011 to November 2012, totaling 924 observations. It was recorded the number of bees leaving and entering the nest, and the type of material transported by them for ten minutes each hour from 5 a.m. to 7 p.m. The bees entered the colony carrying pollen, resin, detritus and also without apparent material. The bees began external activities by 6 a.m. at 20°C and finished at 6 p.m. at 28.8°C. The peak of activity of G. subterranea occurs on schedule from 1 to 2 p.m. Even though G. subterranea makes their nests in underground, their foraging activities are very similar to others stingless bee species that usually nest on tree cavities or aerial places. This indicate that despite their particular nesting way the external factors as climatic ones will significantly modulate their foraging pattern in a daily and seasonal way.

scholarly journals Effects of above-limit ground-level ozone concentrations on the health condition of the silver birch (Betula pendula Roth) assimilation apparatus within the period of 2009–2011

Beskydy ◽  
2012 ◽  
Vol 5 (1) ◽  
pp. 37-42
Author(s):  
Emilie Bednářová
Keyword(s):  
Betula Pendula ◽  
Ground Level ◽  
Health Condition ◽  
Silver Birch ◽  
Epicuticular Waxes ◽  
Tree Stand ◽  
Ground Level Ozone ◽  
Ozone Concentrations ◽  
Analysis Of Results ◽  
Epicuticular Layer

Effects of above-limit ground-level ozone concentrations on the health condition of the silver birch (Betula pendula Roth) assimilation apparatus was monitored using the method of study of changes in epicuticular waxes. These waxes are present on the surface of leaves and protect the plant (and, especially, its assimilation apparatus) against negative environmental effects. Studies were performed in a tree stand of the 2nd age category in altitudes ranging from 600 to 1,050 m in the Ore Mountains (Krušné hory in Czech). It was found out that, as compared with a control stand, the thickness of the wax epicuticular layer decreased with the increasing altitude while concentrations of the ground-level ozone increased. A visible damage of the assimilation apparatus was observed in localities with the highest concentrations of ground-level ozone. Here, not only an overall decrease in the amount of epicuticular waxes was observed but also a degradation of their structure. A statistical analysis of results proved that the loss of epicuticular waxes was significantly dependent on above-limit concentrations of ground-level ozone.

Genetic analysis of plant height and diameter at ground level of silver birch (Betula platyphylla) seedlings

2008 ◽  
Vol 5 (2) ◽  
pp. 147-151
Author(s):  
Gao Fu-Ling ◽  
Li Shao-Chen ◽  
Jiang Ting-Bo
Keyword(s):  
Genetic Analysis ◽  
Plant Height ◽  
Combining Ability ◽  
Ground Level ◽  
General Combining Ability ◽  
Silver Birch ◽  
The Other ◽  
Betula Platyphylla ◽  
Additive Effects ◽  
Diallel Design

AbstractSix silver birch (Betula platyphylla) parents of diverse provenances were crossed according to Griffing 4 diallel design, and the plant height and diameter at ground level (DGL) of their F1 progeny were observed. The analysis of general combining ability (GCA) and specific combining ability (SCA) showed that two phenotypes were simultaneously controlled by additive and non-additive effects. The GCA between two phenotypes in a parent, and GCA of the same phenotype among different parents displayed significant differences: Q2 from Qingyuan was the best of the parents, followed by M2 from Maoer-mountain. On the other hand, the SCA of two phenotypes in a cross and the SCA of a phenotype among different crosses also varied considerably: the cross between E8 from Finland and Q1 from Qingyuan showed the highest SCA of plant height and DGL. The heritability of plant height and diameter at ground level was strong (over 60%), suggesting that these phenotypes can be used for early selection.

scholarly journals A System for Studying Carbon Allocation in Plants Using 11C-Labeled Carbon Dioxide

Radiocarbon ◽  
1983 ◽  
Vol 25 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Youhanna Fares ◽  
J D Goeschl ◽  
C E Magnuson ◽  
C E Nelson ◽  
B R Strain ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Experimental Validation ◽  
Carbon Allocation ◽  
Carbon Assimilation ◽  
Adaptive Responses ◽  
Intact Plants ◽  
Degree Of Confidence ◽  
Short And Long Term ◽  
Integrated Technique

The effects of environmental factors such as water stress, elevated CO2, or temperature on carbon assimilation and allocation in plants have been studied extensively (Gifford and Evans, 1981; Loomis, Rabbinge, and Ng, 1979; Neales and Incoll, 1968). However, the interactions of these processes are not well understood and cannot be predicted with any degree of confidence. Continuous and simultaneous measurements of photosynthesis, transport, and sink activity have never been made during the short- and long-term responses of live, intact plants to step changes in environmental factors. Thus, direct environmental effects and adaptive responses of plants are generally not distinguished. This results in part from limitation in experimental techniques and protocol used in past studies and the lack of experimental validation of hypotheses and models (eg, Goeschl et al, 1976; Magnuson et al, 1979; Smith et al, 1970) dealing with these problems. This paper describes in detail the components of an integrated technique for studying carbon assimilation, transportation and allocation in intact live plants under any set of environmental conditions, using continuously produced 11CO2.

scholarly journals Applied aerial spectroscopy: A case study on remote sensing of an ancient and semi-natural woodland

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260056
Author(s):  
Shara Ahmed ◽  
Catherine E. Nicholson ◽  
Paul Muto ◽  
Justin J. Perry ◽  
John R. Dean
Keyword(s):  
Tree Species ◽  
Low Cost ◽  
Principal Component ◽  
Ground Level ◽  
Empty Space ◽  
Silver Birch ◽  
Dead Trees ◽  
Aerial Vehicle ◽  
Woodland Regeneration

An area of ancient and semi-natural woodland (ASNW) has been investigated by applied aerial spectroscopy using an unmanned aerial vehicle (UAV) with multispectral image (MSI) camera. A novel normalised difference spectral index (NDSI) algorithm was developed using principal component analysis (PCA). This novel NDSI was then combined with a simple segmentation method of thresholding and applied for the identification of native tree species as well as the overall health of the woodland. Using this new approach allowed the identification of trees at canopy level, across 7.4 hectares (73,934 m2) of ASNW, as oak (53%), silver birch (37%), empty space (9%) and dead trees (1%). This UAV derived data was corroborated, for its accuracy, by a statistically valid ground-level field study that identified oak (47%), silver birch (46%) and dead trees (7.4%). This simple innovative approach, using a low-cost multirotor UAV with MSI camera, is both rapid to deploy, was flown around 100 m above ground level, provides useable high resolution (5.3 cm / pixel) data within 22 mins that can be interrogated using readily available PC-based software to identify tree species. In addition, it provides an overall oversight of woodland health and has the potential to inform a future woodland regeneration strategy.

Sign in / Sign up

Export Citation Format

Share Document