scholarly journals A 100% Tree Inventory Using i-Tree Eco Protocol: A Case Study at Auburn University, Alabama, U.S.

2011 ◽  
Vol 37 (5) ◽  
pp. 207-212
Author(s):  
Nicholas Martin ◽  
Arthur Chappelka ◽  
Gary Keever ◽  
Edward Loewenstein
Keyword(s):  
Loblolly Pine ◽  
Urban Forest ◽  
Canopy Cover ◽  
Tree Height ◽  
Auburn University ◽  
Condition Rating ◽  
Tree Inventory ◽  
And Function ◽  
Tree Condition

The Auburn University campus in Auburn, Alabama, U.S., was used as the site for a case study on the applicability of i-Tree Eco using a 100% tree inventory. The 2009-2010 inventory of the managed areas of campus encompassed 238 ha. Information collected from each tree included diameter at breast height (DBH), tree height, crown width, percent dieback, and a tree condition rating. The complete inventory included 7,345 trees with Lagerstroemia spp. (crapemyrtle), Quercus phellos (willow oak), and Pinus taeda (loblolly pine) being the most numerous species on campus. Average DBH and total height of all trees were 16.4 cm and 8.5 m, respectively, with an estimated canopy cover of approximately 16%. Two tree condition ratings were recorded for each tree and results indicated that percent dieback alone is not a sufficient measure to evaluate tree condition. In this case study, i-Tree Eco procedures were found to be an effective and efficient tool, and provided valuable information regarding Auburn University’s urban forest structure and function.

scholarly journals Assessing Urban Forest Canopy Cover Using Airborne or Satellite Imagery

2008 ◽  
Vol 34 (6) ◽  
pp. 334-340
Author(s):  
Jeffrey Walton ◽  
David Nowak ◽  
Eric Greenfield
Keyword(s):  
Remote Sensing ◽  
New York ◽  
Forest Canopy ◽  
Urban Forest ◽  
Canopy Cover ◽  
Classification Methods ◽  
Remote Sensing Techniques ◽  
Many Sources ◽  
Forest Managers

With the availability of many sources of imagery and various digital classification techniques, assessing urban forest canopy cover is readily accessible to most urban forest managers. Understanding the capability and limitations of various types of imagery and classification methods is essential to interpreting canopy cover values. An overview of several remote sensing techniques used to assess urban forest canopy cover is presented. A case study comparing canopy cover percentages for Syracuse, New York, U.S. interprets the multiple values developed using different methods. Most methods produce relatively similar results, but the estimate based on the National Land Cover Database is much lower.

scholarly journals Tree measurements in the urban environment: insights from traditional and digital field instruments to smartphone applications

2021 ◽  
Author(s):  
Rocco Pace ◽  
Emanuela Masini ◽  
Diego Giuliarelli ◽  
Luca Biagiola ◽  
Antonio Tomao ◽  
...  
Keyword(s):  
Spatial Data ◽  
Urban Forest ◽  
Tree Height ◽  
Health Condition ◽  
Urban Trees ◽  
Social Functions ◽  
Measurement Systems ◽  
Tree Inventory ◽  
Size Growth ◽  
Pros And Cons

Urban forests can provide essential environmental and social functions if properly planned and managed. Tree inventory and measurements are a critical part of assessing and monitoring the size, growth, and health condition of urban trees. In this context, the parameters usually collected are DBH and total height, but additional data about crown dimensions (width, length, and crown projection) are required for a comprehensive tree assessment. These data are generally collected by urban foresters through field surveys using tree caliper or diameter tape for DBH, and the electronic ipsometer/clinometer to measure tree height and crown size. Greater detail could be achieved using a digital instrument as Field-Map, a portable computer station to quickly realize dimensional and topographic surveys of trees and forest stands. Finally, the incorporation of the LIDAR scanner into smartphone, as the iPhone 12 Pro, has made this device able to measure tree attributes, as well as additional spatial data in the field. In this study, we tested these three different measurement systems in a field sampling of an urban forest and compared them in terms of measurable parameters, accuracy, cost, and time efficiency. Furthermore, we discussed the pros and cons of each measurement approach and how the resulted data can be used to evaluate ecosystem services of trees and provide guidance on tree management also to reduce potential risks or disservices.

Urban forest restoration cost modeling: a Seattle natural areas case study

2016 ◽  
Author(s):  
Jean M. Daniels ◽  
Weston Brinkley ◽  
Michael D. Paruszkiewicz
Keyword(s):  
Forest Restoration ◽  
Urban Forest ◽  
Cost Modeling ◽  
Natural Areas ◽  
Restoration Cost

Karpophoroi deities and the Attic cult of Ge. Notes on IG II2 4758

2014 ◽  
Vol 7 ◽  
pp. 193-203
Author(s):  
Jenny Wallensten
Keyword(s):  
The Earth ◽  
And Function

Karpophoros, fruit-bearing, is an epithet easily considered as “literary”, i.e., a poetic name with little or no relation to cult. The epigraphic sources, however, clearly show us that gods thus named were offered divine worship. The epithet is found in connection with several deities. Goddesses of agriculture, such as Demeter, and Ge, the Earth, naturally carry this name, but so do Zeus, Dionysos and a goddess known as “The Aiolian”, who was sometimes associated with Agrippina. This paper surveys deities known as karpophoroi and examines what their cult entailed. Its focus is, however, on a brief Acropolis inscription, IG II2 4758, where Ge is honoured as Karpophoros, in accordance with an oracle. The case study provides insights into the Attic cult of Ge, the epithet Karpophoros, as well as the use and function of epithets within Greek dedicatory language.

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 A protocol for sampling vascular epiphyte richness and abundance

2009 ◽  
Vol 25 (2) ◽  
pp. 107-121 ◽  
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.

Retail Suburbanization, Modernization, and Growth in Sydney during Australia’s Postwar Boom

2021 ◽  
pp. 009614422110236
Author(s):  
Matthew Bailey
Keyword(s):  
Capital City ◽  
Growth Strategies ◽  
Capital Cities ◽  
Form And Function ◽  
Urban Core ◽  
Socially Constructed ◽  
And Function ◽  
Retail Formats ◽  
Car Driving

This article uses Sydney as a case study to examine the process of retail decentralization during Australia’s postwar boom, showing how the form and function of capital city retailing changed completely in just a couple of decades. Suburban migration, the emergence of mobile car-driving consumers, socially constructed gender roles, the ongoing importance of public transport networks, planning regimes that sought to concentrate development in designated zones, and business growth strategies that deployed retail formats developed in America all played a role in shaping the form and function of Australian retailing during the postwar boom. In the process, the retail geographies of Australia’s capital cities were transformed from highly centralized distribution structures dominated by the urban core, to decentralized landscapes of retail clusters featuring modern retail forms like the supermarket and shopping center that would come to define Australian retailing for the remainder of the century.

scholarly journals Development and Performance Evaluation of a Very Low-Cost UAV-Lidar System for Forestry Applications

2020 ◽  
Vol 13 (1) ◽  
pp. 77
Author(s):  
Tianyu Hu ◽  
Xiliang Sun ◽  
Yanjun Su ◽  
Hongcan Guan ◽  
Qianhui Sun ◽  
...  
Keyword(s):  
Forest Inventory ◽  
Low Cost ◽  
Canopy Cover ◽  
Tree Height ◽  
Flying Height ◽  
Tree Level ◽  
Forest Site ◽  
Lidar System ◽  
Individual Tree ◽  
Gap Fraction

Accurate and repeated forest inventory data are critical to understand forest ecosystem processes and manage forest resources. In recent years, unmanned aerial vehicle (UAV)-borne light detection and ranging (lidar) systems have demonstrated effectiveness at deriving forest inventory attributes. However, their high cost has largely prevented them from being used in large-scale forest applications. Here, we developed a very low-cost UAV lidar system that integrates a recently emerged DJI Livox MID40 laser scanner (~$600 USD) and evaluated its capability in estimating both individual tree-level (i.e., tree height) and plot-level forest inventory attributes (i.e., canopy cover, gap fraction, and leaf area index (LAI)). Moreover, a comprehensive comparison was conducted between the developed DJI Livox system and four other UAV lidar systems equipped with high-end laser scanners (i.e., RIEGL VUX-1 UAV, RIEGL miniVUX-1 UAV, HESAI Pandar40, and Velodyne Puck LITE). Using these instruments, we surveyed a coniferous forest site and a broadleaved forest site, with tree densities ranging from 500 trees/ha to 3000 trees/ha, with 52 UAV flights at different flying height and speed combinations. The developed DJI Livox MID40 system effectively captured the upper canopy structure and terrain surface information at both forest sites. The estimated individual tree height was highly correlated with field measurements (coniferous site: R2 = 0.96, root mean squared error/RMSE = 0.59 m; broadleaved site: R2 = 0.70, RMSE = 1.63 m). The plot-level estimates of canopy cover, gap fraction, and LAI corresponded well with those derived from the high-end RIEGL VUX-1 UAV system but tended to have systematic biases in areas with medium to high canopy densities. Overall, the DJI Livox MID40 system performed comparably to the RIEGL miniVUX-1 UAV, HESAI Pandar40, and Velodyne Puck LITE systems in the coniferous site and to the Velodyne Puck LITE system in the broadleaved forest. Despite its apparent weaknesses of limited sensitivity to low-intensity returns and narrow field of view, we believe that the very low-cost system developed by this study can largely broaden the potential use of UAV lidar in forest inventory applications. This study also provides guidance for the selection of the appropriate UAV lidar system and flight specifications for forest research and management.

scholarly journals Adjudicating Perspectives on Forest Structure: How Do Airborne, Terrestrial, and Mobile Lidar-Derived Estimates Compare?

2021 ◽  
Vol 13 (12) ◽  
pp. 2297
Author(s):  
Jonathon J. Donager ◽  
Andrew J. Sánchez Meador ◽  
Ryan C. Blackburn
Keyword(s):  
Ponderosa Pine ◽  
Laser Scanning ◽  
Canopy Cover ◽  
Basal Area ◽  
Tree Height ◽  
Absolute Error ◽  
Forest Monitoring ◽  
Individual Tree ◽  
Structural Configurations ◽  
Individual Trees

Applications of lidar in ecosystem conservation and management continue to expand as technology has rapidly evolved. An accounting of relative accuracy and errors among lidar platforms within a range of forest types and structural configurations was needed. Within a ponderosa pine forest in northern Arizona, we compare vegetation attributes at the tree-, plot-, and stand-scales derived from three lidar platforms: fixed-wing airborne (ALS), fixed-location terrestrial (TLS), and hand-held mobile laser scanning (MLS). We present a methodology to segment individual trees from TLS and MLS datasets, incorporating eigen-value and density metrics to locate trees, then assigning point returns to trees using a graph-theory shortest-path approach. Overall, we found MLS consistently provided more accurate structural metrics at the tree- (e.g., mean absolute error for DBH in cm was 4.8, 5.0, and 9.1 for MLS, TLS and ALS, respectively) and plot-scale (e.g., R2 for field observed and lidar-derived basal area, m2 ha−1, was 0.986, 0.974, and 0.851 for MLS, TLS, and ALS, respectively) as compared to ALS and TLS. While TLS data produced estimates similar to MLS, attributes derived from TLS often underpredicted structural values due to occlusion. Additionally, ALS data provided accurate estimates of tree height for larger trees, yet consistently missed and underpredicted small trees (≤35 cm). MLS produced accurate estimates of canopy cover and landscape metrics up to 50 m from plot center. TLS tended to underpredict both canopy cover and patch metrics with constant bias due to occlusion. Taking full advantage of minimal occlusion effects, MLS data consistently provided the best individual tree and plot-based metrics, with ALS providing the best estimates for volume, biomass, and canopy cover. Overall, we found MLS data logistically simple, quickly acquirable, and accurate for small area inventories, assessments, and monitoring activities. We suggest further work exploring the active use of MLS for forest monitoring and inventory.

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