Parameterization of Mangrove Root Structure of Rhizophora stylosa in Coastal Hydrodynamic Model

Mangroves are able to attenuate tsunamis, storm surges, and waves. Their protective function against wave disasters is gaining increasing attention as a typical example of the green infrastructure/Eco-DRR (Ecosystem-based Disaster Risk Reduction) in coastal regions. Hydrodynamic models commonly employed additional friction or a drag forcing term to represent mangrove-induced energy dissipation for simplicity. The well-known Morison-type formula (Morison et al. 1950) has been considered appropriate to model vegetation-induced resistance in which the information of the geometric properties of mangroves, including the root system, is needed. However, idealized vegetation configurations mainly were applied in the existing numerical models, and only a few field observations provided the empirical parameterization of the complex mangrove root structures. In this study, we conducted field surveys on the Iriomote Island of Okinawa, Japan, and Tarawa, Kiribati. We measured the representative parameters for the geometric properties of mangroves, Rhizophora stylosa, and their root system. By analyzing the data, significant correlations for hydrodynamic modeling were found among the key parameters such as the trunk diameter at breast height (DBH), the tree height H, the height of prop roots, and the projected areas of the root system. We also discussed the correlation of these representative factors with the tree age. These empirical relationships are summarized for numerical modeling at the end.

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Spring Freeze Damage of Pecan Bloom: A Review

Horticulturae ◽

10.3390/horticulturae6040082 ◽

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.

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A protocol for sampling vascular epiphyte richness and abundance

Journal of Tropical Ecology ◽

10.1017/s0266467408005786 ◽

2009 ◽

Vol 25 (2) ◽

pp. 107-121 ◽

Cited By ~ 24

Author(s):

Jan H. D. Wolf ◽

S. Robbert Gradstein ◽

Nalini M. Nadkarni

Keyword(s):

Tree Height ◽

Dry Weight ◽

Mantel Test ◽

Tree Size ◽

Tree Level ◽

Trunk Diameter ◽

Host Trees ◽

Epiphyte Communities ◽

Vascular Epiphyte

Abstract:The sampling of epiphytes is fraught with methodological difficulties. We present a protocol to sample and analyse vascular epiphyte richness and abundance in forests of different structure (SVERA). Epiphyte abundance is estimated as biomass by recording the number of plant components in a range of size cohorts. Epiphyte species biomass is estimated on 35 sample-trees, evenly distributed over six trunk diameter-size cohorts (10 trees with dbh > 30 cm). Tree height, dbh and number of forks (diameter > 5 cm) yield a dimensionless estimate of the size of the tree. Epiphyte dry weight and species richness between forests is compared with ANCOVA that controls for tree size. SChao1 is used as an estimate of the total number of species at the sites. The relative dependence of the distribution of the epiphyte communities on environmental and spatial variables may be assessed using multivariate analysis and Mantel test. In a case study, we compared epiphyte vegetation of six Mexican oak forests and one Colombian oak forest at similar elevation. We found a strongly significant positive correlation between tree size and epiphyte richness or biomass at all sites. In forests with a higher diversity of host trees, more trees must be sampled. Epiphyte biomass at the Colombian site was lower than in any of the Mexican sites; without correction for tree size no significant differences in terms of epiphyte biomass could be detected. The occurrence of spatial dependence, at both the landscape level and at the tree level, shows that the inclusion of spatial descriptors in SVERA is justified.

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

The Forestry Chronicle ◽

10.5558/tfc79602-3 ◽

2003 ◽

Vol 79 (3) ◽

pp. 602-612 ◽

Cited By ~ 8

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

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

Canadian Journal of Forest Research ◽

10.1139/x05-059 ◽

2005 ◽

Vol 35 (6) ◽

pp. 1314-1318 ◽

Cited By ~ 5

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.

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Root-Plate Characteristics of Common Aspen in Hemiboreal Forests of Latvia: A Case Study

Forests ◽

10.3390/f12010032 ◽

2020 ◽

Vol 12 (1) ◽

pp. 32

Author(s):

Valters Samariks ◽

Dace Brizga ◽

Jeļena Rūba ◽

Andris Seipulis ◽

Āris Jansons

Keyword(s):

Root System ◽

Complex Structure ◽

Mineral Soil ◽

Negative Relationship ◽

Tree Height ◽

Belowground Biomass ◽

Rooting Depth ◽

Economic Losses ◽

Coarse Roots ◽

Root Plate

Climate change will cause winds to strengthen and storms to become more frequent in Northern Europe. Windstorms reduce the financial value of forests by bending, breaking, or uprooting trees, and wind-thrown trees cause additional economic losses. The resistance of trees to wind damage depends on tree species, tree- and stand-scale parameters, and root-soil plate characteristics such as root-plate size, weight, and rooting depth. The root-soil plate is a complex structure whose mechanical strength is dependent on root-plate width and depth, as the root system provides root attachment with soil and structural support. In Latvia, the common aspen (Populus tremula L.) root system has been studied to develop a belowground biomass model, because information about root system characteristics in relation to tree wind resistance is scarce. The aim of this study was to assess the root-plate dimensions of common aspen stands on fertile mineral soil (luvisol). Study material was collected in the central region of Latvia, where pure mature (41–60 years old) common aspen stands were randomly selected, and dominant trees within the stand were chosen. In total, ten sample trees from ten stands were uprooted. The diameter at breast height (DBH) and tree height (H) were measured for each sample tree, and their roots were excavated, divided into groups, washed, measured, and weighed. The highest naturally moist biomass values were observed for coarse roots, and fine root biomass was significantly lower compared to other root groups. All root group biomass values had a strong correlation with the tree DBH. The obtained results show that there is a close, negative relationship between the relative distance from the stem and the relative root-plate depth distribution.

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Container and Landscape Planting Depth and Root Ball Shaving Affects Magnolia grandiflora Root Architecture and Landscape Performance

Arboriculture & Urban Forestry ◽

10.48044/jauf.2015.024 ◽

2015 ◽

Vol 41 (5) ◽

Author(s):

Edward Gilman ◽

Maria Paz ◽

Chris Harchick

Keyword(s):

Root Architecture ◽

Mechanical Stability ◽

Tree Height ◽

Root Pruning ◽

Weather Event ◽

Planting Depth ◽

Trunk Diameter ◽

Magnolia Grandiflora ◽

Landscape Performance ◽

Tree Height Growth

Plants were grown in a 2 × 2 factorial combination of planting depth in nursery containers and at a landscape installation to study effects on root architecture, growth, and mechanical stability of Magnolia grandiflora L. Planting depth into containers or landscape soil had no impact on bending stress to tilt trunks 40 months after landscape planting, and impacted neither trunk diameter nor tree height growth 68 months later. Trees planted 128 mm deep into 170 L containers had more circling roots at landscape planting and 68 months later than trees planted shallow in containers. Root pruning at landscape planting reduced the container imprint rating on the root system to one-third of that absent root pruning with only a 4 mm reduction in trunk diameter growth over 68 months. Improvement in root architecture from root pruning likely outweighs the rarely encountered downside of slightly less anchorage in an extreme weather event simulated by winching trunks. Trees planted 5 cm above grade were slightly—but significantly—less stable in landscape than trees planted deeper (10 cm below grade). Root pruning at planting to remove roots on root ball periphery appeared to improve root architecture while only slightly impacting growth and anchorage.

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Nitrogen and Flowering Dogwood. I. Impact of Nitrogen Fertilization Rate on the Occurrence of Spot Anthracnose, Powdery Mildew, and Cercospora Leaf Spot and Their Effect on Tree Growth

Journal of Environmental Horticulture ◽

10.24266/0738-2898-26.4.197 ◽

2008 ◽

Vol 26 (4) ◽

pp. 197-203

Author(s):

A.K. Hagan ◽

J.R. Akridge ◽

K.L. Bowen

Keyword(s):

Powdery Mildew ◽

Nitrogen Fertilization ◽

Leaf Spot ◽

Tree Height ◽

Fertilization Rate ◽

Spot Intensity ◽

Cercospora Leaf Spot ◽

Trunk Diameter ◽

Flowering Dogwood ◽

N Rates

Abstract Impact of nitrogen (N) rate on spot anthracnose, powdery mildew, and Cercospora leaf spot as well as their impact on the growth of field-grown ‘Cloud 9’ and ‘Cherokee Chief’ flowering dogwood was assessed in 2003, 2004, and 2005. From 2001 to 2005, ammonium nitrate was applied at 4.1, 8.3, 16.5, 33.0 and 66.0 g N·m−2 (37.5, 75, 150, 300, 600 lb N·A−1). Heritage 50W fungicide was applied to one ‘Cherokee Chief’ and ‘Cloud 9’ flowering dogwood in each plot, while the second was untreated. Powdery mildew and Cercospora leaf spot were impacted by N rate more than spot anthracnose. In two of three years, powdery mildew intensified, particularly on the non-treated trees, as N rates increased. Cercospora leaf spot intensity (AUDPCI) and defoliation (AUDPCD) on the fungicide-treated and non-treated trees was influenced by N-rate in two of three and one of three years, respectively. Regardless of fungicide treatment, Cercospora leaf spot incited leaf spotting and defoliation was often lower at the two highest than the two lowest N rates. A reduction in the bract and leaf spot phases of spot anthracnose at the highest N rate was noted in 2004. While spot anthracnose was negatively correlated with trunk diameter in all three years and tree height in 2003 and 2004, Cercospora leaf spot intensity and defoliation were negatively correlated with tree height and trunk diameter in all three and two of three years, respectively. Powdery mildew had no impact on tree height or trunk diameter. Heritage 50W not only controlled spot anthracnose and powdery mildew but also slowed Cercospora leaf spot development sufficiently to enhance leaf retention and fall color.

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The epiphyte vegetation of the palm Socratea exorrhiza - correlations with tree size, tree age and bryophyte cover

Journal of Tropical Ecology ◽

10.1017/s0266467403003092 ◽

2003 ◽

Vol 19 (1) ◽

pp. 81-90 ◽

Cited By ~ 83

Author(s):

Gerhard Zotz ◽

Birgit Vollrath

Keyword(s):

Attachment Site ◽

Tree Height ◽

Vertical Axis ◽

Tree Size ◽

Tree Age ◽

Species Trees ◽

Lowland Rain Forest ◽

Vascular Epiphytes ◽

Palm Trees ◽

Socratea Exorrhiza

We conducted a survey of the epiphyte flora growing on the stilt palm Socratea exorrhiza in a primary lowland rain forest in Panama by means of a canopy crane. For each palm in a 0.9-ha plot, we determined diameter at breast height, tree height, per cent bryophyte cover and the number, identity and attachment site of all vascular epiphytes. The 118 palm trees hosted a total of 701 epiphytes and hemi-epiphytes, belonging to 66 species. Trees were estimated to be c. 20 y old before colonization with vascular epiphytes began. Epiphyte species were highly clumped and segregated along the vertical axis of the trunk. Sequential colonization led to an increased number of species and individuals as the tree grows. Epiphytes were associated with bryophyte patches much more than expected by chance, but no species seemed to depend upon them for establishment. The influence of tree size, age and bryophyte cover on the composition of the epiphyte community are discussed.

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Deciding Where to Sleep: Spatial Levels of Nesting Selection in Chimpanzees (Pan troglodytes) Living in Savanna at Issa, Tanzania

International Journal of Primatology ◽

10.1007/s10764-020-00186-z ◽

2020 ◽

Vol 41 (6) ◽

pp. 870-900 ◽

Cited By ~ 1

Author(s):

R. Adriana Hernandez-Aguilar ◽

Trond Reitan

Keyword(s):

Pan Troglodytes ◽

Site Selection ◽

Spatial Scales ◽

Tree Height ◽

Important Variable ◽

Physical Characteristics ◽

Individual Tree ◽

Trunk Diameter ◽

Nesting Site ◽

Nesting Sites

AbstractTo understand how animals select resources we need to analyze selection at different spatial levels or scales in the habitat. We investigated which physical characteristics of trees (dimensions and structure, e.g., height, trunk diameter, number of branches) determined nesting selection by chimpanzees (Pan troglodytes) on two different spatial scales: individual nesting trees and nesting sites. We also examined whether individual tree selection explained the landscape pattern of nesting site selection. We compared the physical characteristics of actual (N = 132) and potential (N = 242) nesting trees in nesting sites (in 15 plots of 25 m × 25 m) and of all trees in actual and potential nesting sites (N = 763 in 30 plots of 25 m × 25 m). We collected data in May and June 2003 in Issa, a dry and open savanna habitat in Tanzania. Chimpanzees selected both the site they used for nesting in the landscape and the trees they used to build nests within a nesting site, demonstrating two levels of spatial selection in nesting. Site selection was stronger than individual tree selection. Tree height was the most important variable for both nesting site and tree selection in our study, suggesting that chimpanzees selected both safe sites and secure trees for sleeping.

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