Distribution and Succession of Epiphytic Lichens on Picea Abies Branches in a Boreal Forest, Central Norway

1994 ◽  
Vol 26 (2) ◽  
pp. 149-169 ◽  
Author(s):  
Olga Hilmo
Keyword(s):  
Picea Abies ◽  
Correspondence Analysis ◽  
Tree Height ◽  
Tree Age ◽  
Epiphytic Lichens ◽  
Mature Trees ◽  
Ecological Requirements ◽  
Lichen Community ◽  
Lichen Cover ◽  
Old Trees

AbstractThe distribution of epiphytic lichens on branches of a stand of Picea abies has been mapped, and patterns of succession and community structure are described. Many crustose species are of particular interest since little is known about their ecological requirements (e.g. Fuscidea pusilla Tønsb., Japewia subaurifera Muhr & Tønsb. and Gyalideopsis alnicola Noble & Vězda). Numerical treatment (correspondence analysis and canonical correspondence analysis) of the species data was used to study the lichen distribution in relation to measured environmental variables. Tree age, tree height and branch height above ground are shown to be the most important variables to explain the species distribution. No significant relationship was found between branch compass point and the distribution of lichens. The species composition and cover changed from young to old trees. The largest variation in the lichen vegetation was found on the branches of young trees. A more homogeneous and stable lichen community appears on branches of mature trees. A clear zonation of the epiphytic vegetation develops as the branches grow, resulting in the occurrence of typical ‘branch-tip’ and ‘branch-base’ species. The highest number of species was recorded on the outermost part of branches before lichen cover reached the maximum. Hyperepiphytic thalli were mainly located in specific areas with high lichen cover on the branches. Lichens with reduced vitality were most common at the base of branches.

scholarly journals Mutual Influences of Urban Microclimate and Urban Trees: An Investigation of Phenology and Cooling Capacity

Forests ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 533
Author(s):  
Celina H. Stanley ◽  
Carola Helletsgruber ◽  
Angela Hof
Keyword(s):  
Species Differences ◽  
Tree Height ◽  
Growing Season ◽  
Cooling Capacity ◽  
Urban Trees ◽  
Tree Age ◽  
Surface Cooling ◽  
Urban Heat ◽  
Old Trees ◽  
Suitable Measure

This paper presents an empirical study on urban tree growth and regulating ecosystem services along an urban heat island (UHI) intensity gradient. The UHI effect on the length of the growing season and the association of cooling and shading with species, age, and size of trees was studied in Salzburg, Austria. Results show that areas with a low UHI intensity differed from areas with a medium or high UHI intensity significantly in three points: their bud break began later, the leaf discoloration took longer, and the growing season was shorter. After leaves have developed, trees cool the surface throughout the whole growing season by casting shadows. On average, the surfaces in the crown shade were 12.2 °C cooler than those in the sun. The tree characteristics had different effects on the cooling performance. In addition to tree height and trunk circumference, age was especially closely related to surface cooling. If a tree’s cooling capacity is to be estimated, tree age is the most suitable measure, also with respect to its assessment effort. Practitioners are advised to consider the different UHI intensities when maintaining or enhancing public greenery. The cooling capacity of tall, old trees is needed especially in areas with a high UHI intensity. In the future, species differences should be examined to determine the best adapted species for the different UHI intensities. The present results can be the basis for modeling future mutual influences of microclimate and urban trees.

Effects of recreational rock climbing and environmental variation on a sandstone cliff-face lichen community

Botany ◽  
2012 ◽  
Vol 90 (4) ◽  
pp. 253-259 ◽  
Author(s):  
Matthew D. Adams ◽  
Kamil Zaniewski
Keyword(s):  
Correspondence Analysis ◽  
Detrended Correspondence Analysis ◽  
Rock Climbing ◽  
Environmental Response ◽  
Linear Regression Models ◽  
Community Group ◽  
Lichen Community ◽  
The North ◽  
Lichen Cover ◽  
Group Variation

Lichen community composition was evaluated for both lichen cover and richness on a cliff face commonly used for recreational rock climbing. The sandstone outcrop is located on the Sibley Peninsula, which extends from the north shore of Lake Superior. One-hundred and twenty plots were examined. Each plot was 1 m2 in size, with 60 plots located on unclimbed cliff sections and 60 more located where recreational rock climbing regularly occurs. Lichen richness and cover were significantly lower on the rock climbing sections compared with unclimbed sections. Linear regression models indicated significant relationships with cover and richness to environmental response variables and climbing treatment. Detrended correspondence analysis indicated a separation of lichen community groups on this cliff, and major separations occurred between plots in each climbing treatment. Canonical correspondence analysis indicated a significant amount of community group variation between climbed and unclimbed locations related to climbing treatment and aspect of the plots. Climbing is found to have an impact on this sandstone cliff-face lichen community.

Occurrence, proportion, and vertical distribution of red heartwood in paper birch

2008 ◽  
Vol 38 (7) ◽  
pp. 1996-2002 ◽  
Author(s):  
Guillaume Giroud ◽  
Alain Cloutier ◽  
Jérôme Alteyrac
Keyword(s):  
Vertical Distribution ◽  
Tree Height ◽  
Tree Age ◽  
Quebec City ◽  
Betula Papyrifera ◽  
Breast Height ◽  
Birch Trees ◽  
Paper Birch ◽  
Thick Disks ◽  
Old Trees

Normal paper birch ( Betula papyrifera Marsh.) wood has a clear and uniform color. However, some paper birch trees contain reddish-brown-, discolored wood known as red heartwood. Its occurrence, proportion, and vertical distribution were investigated. One hundred and fifty trees were randomly sampled from three stands located at the Montmorency Forest, 75 km north of Quebec City, Quebec, Canada. A subsample of 18 trees showing occurrence of red heartwood at stump height were felled, and 5 cm thick disks were cut at every 0.5 m of height. Red heartwood volume, proportion, and vertical distribution were determined from the disks. Trees with larger diameter at breast height and lower tree height had a higher probability of red heartwood occurrence. Red heartwood starts occurring in 40-year-old trees on average in the stands studied. The volume of red heartwood was positively correlated with tree age, and the proportion of red heartwood was positively related to tree age, and negatively related to the amount of sunlight on the live crown. Red heartwood proportion was 13.3% of the tree merchantable volume, mostly located under the live crown.

scholarly journals Mangrove Productivity Estimation using Modelling Approach and Tree Parameters Assessment

2019 ◽  
Vol 12 ◽  
pp. 194008291987213
Author(s):  
Waseem R. Khan ◽  
Syaizwan Z. Zulkifli ◽  
Mohamad Roslan B. M. Kasim ◽  
Ahmad Mustapha Pazi ◽  
Roslan Mostapa ◽  
...  
Keyword(s):  
Tree Height ◽  
Tree Age ◽  
Biomass Estimation ◽  
Age Group ◽  
Above Ground Biomass ◽  
Rhizophora Apiculata ◽  
Nutrient Productivity ◽  
Old Trees ◽  
Mangrove Trees ◽  
Modelling Approach

This study used productivity models and above ground biomass to investigate productivity in different sites of MMFR. Ninety Rhizophora apiculata leaf samples were collected from different compartments (18, 31, 71, 74, 42 and 55) based on tree age and management. For biomass calculation, tree height and diameter were measured in plot of 10m x 10m in compartment 18, 31, 71, 74 and 67. The age of the trees were as follows: compartment 18 and 31 with 15-year-old, compartment 71 and 74 with 25-year-old and compartment 67 with 30-year-old mangrove trees. Compartment 42 and 55 are classified as virgin jungle reserve (VJR). Compartment 67 was not taken as a sample site due to technical reason and compartments in VJR were not considered for biomass estimation. Sixteen variables; stable isotopes (δ13C, δ15N), macronutrients (C, N, P), cations (Ca, Mg, Na, K) and trace elements (Cd, Cu, Fe, Mn, Pb, Zn) were analyzed. Productivity models and calculated biomass for investigated compartments showed similar trends. In 15-year age group; compartment 18 showed higher productivity than in 31. For the 25-year age group; compartment 74 had higher productivity than 71. No prominent increase was observed in biomass between 15-year old and 30-year old trees. Furthermore, with moderate N and δ15N loading input, compartments showed more productivity. The results conclude that MMFR is a sustainably managed mangrove forest and its productivity could be monitored using nutrient productivity models.

scholarly journals Spring Freeze Damage of Pecan Bloom: A Review

Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 82
Author(s):  
Amandeep Kaur ◽  
Louise Ferguson ◽  
Niels Maness ◽  
Becky Carroll ◽  
William Reid ◽  
...  
Keyword(s):  
Tree Height ◽  
The United States ◽  
Reproductive Organs ◽  
Tree Age ◽  
The Us ◽  
Nut Production ◽  
Freeze Damage ◽  
Terminal Buds ◽  
And Function ◽  
The Impact

Pecan is native to the United States. The US is the world’s largest pecan producer with an average yearly production of 250 to 300 million pounds; 80 percent of the world’s supply. Georgia, New Mexico, Texas, Arizona, Oklahoma, California, Louisiana, and Florida are the major US pecan producing states. Pecan trees frequently suffer from spring freeze at bud break and bloom as the buds are quite sensitive to freeze damage. This leads to poor flower and nut production. This review focuses on the impact of spring freeze during bud differentiation and flower development. Spring freeze kills the primary terminal buds, the pecan tree has a second chance for growth and flowering through secondary buds. Unfortunately, secondary buds have less bloom potential than primary buds and nut yield is reduced. Spring freeze damage depends on severity of the freeze, bud growth stage, cultivar type and tree age, tree height and tree vigor. This review discusses the impact of temperature on structure and function of male and female reproductive organs. It also summarizes carbohydrate relations as another factor that may play an important role in spring growth and transition of primary and secondary buds to flowers.

scholarly journals Potential of Alnus acuminata based agroforestry for carbon sequestration and other ecosystem services in Rwanda

2021 ◽  
Author(s):  
Athanase R. Cyamweshi ◽  
Shem Kuyah ◽  
Athanase Mukuralinda ◽  
Catherine W. Muthuri
Keyword(s):  
Ecosystem Services ◽  
Carbon Sequestration ◽  
Soil Fertility ◽  
Tree Age ◽  
Average Height ◽  
Total Biomass ◽  
Biomass Carbon ◽  
Alnus Acuminata ◽  
Sequestration Potential ◽  
Old Trees

AbstractAlnus acuminata Kunth. (alnus) is widely used in agroforestry systems across the globe and is believed to provide multiple ecosystem services; however, evidence is lacking in agroforestry literature to support the perceived benefits, particularly in Rwanda. To understand carbon sequestration potential and other benefits of alnus, a household survey, tree inventory and destructive sampling were conducted in north-western Rwanda. Over 75% of the respondents had alnus trees in their farms. The trees provide stakes for climbing beans, firewood and timber. They also improve soil fertility and control soil erosion. Farmers had between 130 and 161 alnus trees per hectare with an average height of 7.7 ± 0.59 m and diameter at breast height of 16.3 ± 1.39 cm. The largest biomass proportion was found in stems (70.5%) while branches and leaves stock about 16.5 and 13% of the total biomass, respectively. At farm level, aboveground biomass of alnus trees was estimated to be 27.2 ± 0.7 Mg ha−1 representing 13.6 Mg of carbon (C) per hectare. Biomass carbon increased with tree size, from 7.1 ± 0.2 Mg C ha−1 in 3 years old trees to 34.4 ± 2.2 Mg C ha−1 in 10 years old trees. The converse was observed with elevation; biomass carbon decreased with increasing elevation from 21.4 ± 1.29 Mg C ha−1 at low (2011–2110 m) to 9.6 ± 0.75 Mg C ha−1 in the high elevation (> 2510 m). In conclusion, alnus agroforestry significantly contributes to carbon sequestration, although the magnitude of these benefits varies with tree age and elevation. Planting alnus trees on farms can meet local needs for stakes for climbing beans, wood and soil fertility improvement, as well as the global need for regulation of climate change.

scholarly journals Differentiating mature and old-growth forests in the Upper Foothills and Subalpine Subregions of west-central Alberta

2003 ◽  
Vol 79 (3) ◽  
pp. 602-612 ◽  
Author(s):  
Luigi E Morgantini ◽  
John L Kansas
Keyword(s):  
Forest Management ◽  
Growth Index ◽  
Tree Height ◽  
Tree Age ◽  
Old Growth ◽  
West Central ◽  
Decay Class ◽  
Management Area ◽  
Growth Attributes ◽  
Live Tree

Weyerhaeuser Company Ltd. is developing harvest strategies that will maintain appropriate levels of late to very late seral stages ("old growth") in its Drayton Valley Forest Management Area. This management area encompasses 490 570 ha in the Foothills and Rocky Mountain Natural Regions of west-central Alberta. In planning for future forest landscapes, Weyerhaeuser intends to maintain a range of age structures consistent with the ecological processes characteristic of each natural region and subregion. The absence of a discrete point separating mature forest from old growth means that the age at which a stand is currently identified as "old growth" and subject to special management practices is arbitrary. In a research study initiated in the summer of 2000, we seek to understand the differences in structure and composition between forests of various ages and topographic site conditions (elevation, aspect, and slope angle). Using 95 sampling plots in a 123-km2 study area in the Upper Foothills and Subalpine Natural Subregions, we quantified vegetation structure and composition for stands ranging in age from 70 to 300 years. Variables measured and analysed included live-tree height and diameter, snag density, diameter and decay class, downed woody material volume, diameter and decay class, vascular plant species richness, sapling and regeneration density, and duff depth. An old-growth index was developed for each sampled stand that took into account multiple attributes. Preliminary results indicate that specific attributes (snag basal area and density, decay stage and density of downed woody material, variation in live-tree age, and variation in live-tree height and age) separate a younger forest from a more mature one and hence may describe "old-growth" conditions. The age of onset of these old-growth attributes is variable but appears to occur between 160 and 180 years. Key factors other than stand age that contribute to or modify the development of old-growth attributes (as measured by the old-growth index) are elevation and moisture regime (as modified by site position). Further investigation is required to more accurately assess the effect of site factors on old-growth attributes. These results are now used by Weyerhaeuser to address retention of late seral stages in long-term forest planning. Key words: old growth, mature forests, old growth protection, forest management, Alberta, Weyerhaeuser, Rocky Mountains foothills

Incidence of main stem infections of lodgepole pine by western gall rust decreases with tree age

2005 ◽  
Vol 35 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Peter V Blenis ◽  
Wuhan Li
Keyword(s):  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Stem Elongation ◽  
Tree Height ◽  
Shoot Elongation ◽  
Main Stem ◽  
Tree Age ◽  
Precommercial Thinning ◽  
Two Factors ◽  
Artificial Inoculations

Infection of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) by western gall rust has been shown to decrease with tree height and age, but the effects of those two factors have not been separated. Five replicate artificial inoculations were done on a total of 327 trees of different ages in two height classes. Temperature and percentage of spore germination at the height of inoculation, shoot development (stem elongation at the time of inoculation as a proportion of final shoot elongation), main stem leader length at the time of inoculation, tree height, and tree age were measured. Modeled percentages of infected trees and the number of galls per 10 cm of shoot length decreased by 85% and 88%, respectively, as tree age increased between 2 and 10 years, indicating the undesirability of early, aggressive precommercial thinning of lodgepole pine stands in areas where western gall rust is common. By controlling and (or) statistically accounting for inoculum, microclimate, and phenological factors, it was possible to demonstrate that changes in susceptibility with tree age are sufficient to account for the reduction in infection with tree height.

WITHIN–TREE VARIATION IN PHLOEM CELL DIMENSIONS AND PROPORTIONS IN EUCALYPTUS GLOBULUS

IAWA Journal ◽  
2000 ◽  
Vol 21 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Teresa Quilhó ◽  
Helena Pereira ◽  
Hans Georg Richter
Keyword(s):  
Wall Thickness ◽  
Eucalyptus Globulus ◽  
Tree Height ◽  
Sieve Tube ◽  
Bark Thickness ◽  
Cell Type ◽  
Fibre Width ◽  
Axial Variation ◽  
Sieve Tubes ◽  
Old Trees

The axial variation of bark thickness and quantitative anatomical features of Eucalyptus globulus bark were analysed for one site based on individual measurements of ten 15-year-old trees at six height levels (DBH, 5%, 15%, 35%, 55% and 75% of total tree height). The parameters studied were: length, tangential diameter and percentage of sieve tubes; length, width, cell wall thickness and percentage of fibres; height and percentage of rays; percentage of sclereids in the secondary phloem. Bark thickness decreases from base to top of the tree. Fibre width and wall thickness decrease from base upwards. No distinct axial patterns of variation were observed for the other biometric variables studied. Parenchyma is the main cell type of the bark (50%) followed by fibres (27.9%), rays (12.1%), sieve tubes (2.7%), and sclereids (7.3%). The cell type proportions vary significantly within the tree, i.e., parenchyma, ray and sclereid proportions decrease, fibre and sieve tube proportions increase towards the top of the tree.

scholarly journals Endemic Cyprus Scops Owl Otus cyprius Readily Breeds in Artificial Nest Boxes

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1775
Author(s):  
Savvas Iezekiel ◽  
Reuven Yosef ◽  
Constantinos Themistokleus ◽  
Dimitrios E. Bakaloudis ◽  
Christos G. Vlachos ◽  
...  
Keyword(s):  
Rural Areas ◽  
Habitat Preferences ◽  
Bird Species ◽  
Laying Date ◽  
Artificial Nests ◽  
Breeding Parameters ◽  
Island Endemic ◽  
Nest Boxes ◽  
Ecological Requirements ◽  
Old Trees

As is well-known, endemic island bird species are especially vulnerable to extinction from anthropogenic environmental change and reduced fitness compared with mainland taxa. The Cyprus Scops Owl, Otus cyprius, is a recently recognized island endemic species whose ecology and breeding biology have not been studied. It nests mainly in holes in trees and buildings, so the felling of old trees, modern architectural practices, and the renovation of old houses in villages may reduce nest site availability. Its population trend is also unknown. Therefore, to better determine its ecological requirements and habitat preferences we placed nest boxes in rural areas adjacent to the forest, in the forest, and in the ecotone between them, and used breeding success as our indicator of habitat suitability. We found that breeding parameters like laying date, clutch size, length of the incubation period, hatching day, hatching success, and number of nestlings did not differ between the three habitats. Despite the low level of nest box occupancy rate (5–11%) the endemic Cyprus Scops Owl readily breeds in artificial nests. Therefore, although we are unaware of any current threats to the Cyprus Scops Owl, we recommend that its conservation be prioritized, including studies, monitoring, habitat conservation, and the provision of nest boxes.

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