scholarly journals A Method to Count Olive Trees in Heterogenous Plantations from Aerial Photographs

2017 ◽  
Author(s):  
Yann H. Chemin ◽  
Pieter S.A. Beck
Keyword(s):  
Olive Tree ◽  
Cultural Value ◽  
Aerial Photographs ◽  
Median Error ◽  
Mediterranean Regions ◽  
Closed Canopy ◽  
Olive Trees ◽  
Individual Trees ◽  
Multiple Trees ◽  
Reference Counts

Olive trees have been of economic and cultural value since pre-Roman times, and continue to dominate landscapes and agriculture in many mediterranean regions. Recent mass losses of olive trees in Southern Italy due to an exotic plant pathogen highlight the need for methods that to monitor the olive trees in a landscape or region operationally. Here, we develop a method for counting olive trees from aerial photographs and test it in areas with a high diversity of olive tree ages, sizes, and shapes. This heterogeneity complicates tree counting as centennial trees often have crowns that are split into multiple segments, resembling multiple crowns, while nearby crowns often form a semi-closed canopy comprising multiple trees. Comparisons with reference counts in two 20 ha sites and over three different years indicate the automated counts tend to be reasonably accurate (median error 13%, n = 6), but heavily influenced by a few olive orchards with particularly high planting densities and a relatively closed canopy in which distinguishing individual trees is challenging. Overall, the algorithm estimated tree densities well (counting 82 to 109 trees/ha versus 87 to 104 trees/ha in the reference counts), indicating the method is suitable to track the number of olive trees over large areas.

scholarly journals Registration and promotion of monumental olive trees in Greece.

2020 ◽  
Vol 7 (4) ◽  
pp. 107-121
Author(s):  
Stavros Koniditsiotis
Keyword(s):  
Cultural Heritage ◽  
Everyday Life ◽  
Olive Tree ◽  
Morphological Features ◽  
Cultural Value ◽  
Cultural Characteristics ◽  
History Of ◽  
Key Issues ◽  
Olive Trees ◽  
Folk Tradition

The history of the olive tree, its cultivation and its products is known for centuries. Some olive tree have survived over millennia and their history dates back to antiquity. In many cases, it is related to mythology and religion. The olive tree is associated with folk tradition, people's everyday life, and customs. In Greece, monumental olive trees are found in the Peloponnese, Crete, Euboea, Chios, Pelion and Attica.  This paper explores and describes the particular morphological features such as shape, size, wood, cavities and age, as well as the cultural characteristics such as historical or religious events, myths and traditions that define an olive tree and characterize it as monumental. The main aim of our research is to examine the key position that monumental olive trees and their materialistic and symbolic manifestations consist a natural and cultural heritage as well. In this framework the study focuses on various key issues related to monumental olives trees and their natural, historical, social and cultural value.

Every Olive Tree in the Garden of Gethsemane

2013 ◽  
Vol 3 (2) ◽  
pp. 111-115 ◽  
Author(s):  
Wendy Babcox
Keyword(s):  
Olive Tree ◽  
Photographic Images ◽  
The Future ◽  
Olive Trees ◽  
The Many ◽  
Radical Transformation

Every Olive Tree in the Garden of Gethsemane is a suite of photographic images of each of the twenty-three olive trees in the garden. Situated at the foot of the Mount of Olives in Jerusalem, the Garden of Gethsemane is known to many as the site where Jesus and his disciples prayed the night before his crucifixion. The oldest trees in the garden date to 1092 and are recognized as some of the oldest olive trees in existence. The older trees are a living and symbolic connection to the distant past, while younger trees serve as a link to the future. The gnarled trunks seem written with the many conflicts that have been waged in an effort to control this most-contested city; a city constantly on the threshold of radical transformation.

scholarly journals Analytical Characterization of Water-Soluble Constituents in Olive-Derived By-Products

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1299
Author(s):  
Pablo Doménech ◽  
Aleta Duque ◽  
Isabel Higueras ◽  
José Luis Fernández ◽  
Paloma Manzanares
Keyword(s):  
Olive Tree ◽  
Mediterranean Area ◽  
Water Soluble ◽  
Olive Pomace ◽  
Olive Leaves ◽  
Olive Stone ◽  
Olive Trees ◽  
Tree Pruning ◽  
By Products

Olive trees constitute one of the largest agroindustries in the Mediterranean area, and their cultivation generates a diverse pool of biomass by-products such as olive tree pruning (OTP), olive leaves (OL), olive stone (OS), and extracted olive pomace (EOP). These lignocellulosic materials have varying compositions and potential utilization strategies within a biorefinery context. The aim of this work was to carry out an integral analysis of the aqueous extractives fraction of these biomasses. Several analytical methods were applied in order to fully characterize this fraction to varying extents: a mass closure of >80% was reached for EOP, >76% for OTP, >65% for OS, and >52% for OL. Among the compounds detected, xylooligosaccharides, mannitol, 3,4-dihydroxyphenylglycol, and hydroxytyrosol were noted as potential enhancers of the valorization of said by-products. The extraction of these compounds is expected to be more favorable for OTP, OL, and EOP, given their high extractives content, and is compatible with other utilization strategies such as the bioconversion of the lignocellulosic fraction into biofuels and bioproducts.

scholarly journals Processing Effect and Characterization of Olive Oils from Spanish Wild Olive Trees (Olea europaea var. sylvestris)

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1304
Author(s):  
Francisco Espínola ◽  
Alfonso M. Vidal ◽  
Juan M. Espínola ◽  
Manuel Moya
Keyword(s):  
Phenolic Compounds ◽  
Volatile Compounds ◽  
Olive Tree ◽  
Extraction Yield ◽  
Point Of View ◽  
Human Consumption ◽  
Analytical Point ◽  
Wild Olive ◽  
Olive Trees

Wild olive trees have important potential, but, to date, the oil from wild olives has not been studied significantly, especially from an analytical point of view. In Spain, the wild olive tree is called “Acebuche” and its fruit “Acebuchina”. The objective of this work is to optimize the olive oil production process from the Acebuchina cultivar and characterize the oil, which could be marketed as healthy and functional food. A Box–Behnken experimental design with five central points was used, along with the Response Surface Methodology to obtain a mathematical experimental model. The oils from the Acebuchina cultivar meet the requirements for human consumption and have a good balance of fatty acids. In addition, the oils are rich in antioxidants and volatile compounds. The highest extraction yield, 12.0 g oil/100 g paste, was obtained at 90.0 min and the highest yield of phenolic compounds, 870.0 mg/kg, was achieved at 40.0 °C, and 90.0 min; but the maximum content of volatile compounds, 26.9 mg/kg, was obtained at 20 °C and 30.0 min. The oil yield is lower than that of commercial cultivars, but the contents of volatile and phenolic compounds is higher.

scholarly journals Controlling the Spatial Spread of a Xylella Epidemic

2021 ◽  
Vol 83 (4) ◽  
Author(s):  
Sebastian Aniţa ◽  
Vincenzo Capasso ◽  
Simone Scacchi
Keyword(s):  
Spatial Structure ◽  
Numerical Simulations ◽  
Control Strategies ◽  
Xylella Fastidiosa ◽  
Cost Effective ◽  
Olive Tree ◽  
Control Measures ◽  
Weed Biomass ◽  
Spatial Spread ◽  
Olive Trees

AbstractIn a recent paper by one of the authors and collaborators, motivated by the Olive Quick Decline Syndrome (OQDS) outbreak, which has been ongoing in Southern Italy since 2013, a simple epidemiological model describing this epidemic was presented. Beside the bacterium Xylella fastidiosa, the main players considered in the model are its insect vectors, Philaenus spumarius, and the host plants (olive trees and weeds) of the insects and of the bacterium. The model was based on a system of ordinary differential equations, the analysis of which provided interesting results about possible equilibria of the epidemic system and guidelines for its numerical simulations. Although the model presented there was mathematically rather simplified, its analysis has highlighted threshold parameters that could be the target of control strategies within an integrated pest management framework, not requiring the removal of the productive resource represented by the olive trees. Indeed, numerical simulations support the outcomes of the mathematical analysis, according to which the removal of a suitable amount of weed biomass (reservoir of Xylella fastidiosa) from olive orchards and surrounding areas resulted in the most efficient strategy to control the spread of the OQDS. In addition, as expected, the adoption of more resistant olive tree cultivars has been shown to be a good strategy, though less cost-effective, in controlling the pathogen. In this paper for a more realistic description and a clearer interpretation of the proposed control measures, a spatial structure of the epidemic system has been included, but, in order to keep mathematical technicalities to a minimum, only two players have been described in a dynamical way, trees and insects, while the weed biomass is taken to be a given quantity. The control measures have been introduced only on a subregion of the whole habitat, in order to contain costs of intervention. We show that such a practice can lead to the eradication of an epidemic outbreak. Numerical simulations confirm both the results of the previous paper and the theoretical results of the model with a spatial structure, though subject to regional control only.

Eighty years of change: vegetation in the montane ecoregion of Jasper National Park, Alberta, Canada

2002 ◽  
Vol 32 (11) ◽  
pp. 2010-2021 ◽  
Author(s):  
Jeanine M Rhemtulla ◽  
Ronald J Hall ◽  
Eric S Higgs ◽  
S Ellen Macdonald
Keyword(s):  
National Park ◽  
Vegetation Change ◽  
Fire Regime ◽  
Reference Conditions ◽  
Habitat Diversity ◽  
Climatic Conditions ◽  
Aerial Photographs ◽  
Contributing Factors ◽  
Jasper National Park ◽  
Closed Canopy

Repeat ground photographs (taken in 1915 and 1997) from a series of topographical survey stations and repeat aerial photographs (flown in 1949 and 1991) were analysed to assess changes in vegetation composition and distribution in the montane ecoregion of Jasper National Park, in the Rocky Mountains of Alberta, Canada. A quantitative approach for assessing relative vegetation change in repeat ground photographs was developed and tested. The results indicated a shift towards late-successional vegetation types and an increase in crown closure in coniferous stands. Grasslands, shrub, juvenile forest, and open forests decreased in extent, and closed-canopy forests became more prevalent. The majority of forest stands succeeded to dominance by coniferous species. Changes in vegetation patterns were likely largely attributable to shifts in the fire regime over the last century, although climatic conditions and human activity may also have been contributing factors. Implications of observed changes include decreased habitat diversity, increased possibility of insect outbreaks, and potential for future high-intensity fire events. Results of the study increase knowledge of historical reference conditions and may help to establish restoration goals for the montane ecoregion of the park.

scholarly journals First Report of Phytophthora megasperma and Pythium irregulare As Olive Tree Root Pathogens

Plant Disease ◽  
1997 ◽  
Vol 81 (10) ◽  
pp. 1216-1216 ◽  
Author(s):  
M. E. Sánchez-Hernández ◽  
A. Ruiz-Dávila ◽  
A. Trapero-Casas
Keyword(s):  
Root Rot ◽  
Olive Tree ◽  
The United States ◽  
Damping Off ◽  
Phytophthora Megasperma ◽  
Root Rots ◽  
Foliar Symptoms ◽  
Root Pathogens ◽  
Root Necrosis ◽  
Olive Trees

Several species of the genus Phytophthora are associated with root rot and trunk cankers in olive trees (Olea europaea L.). Among them, Phytophthora megasperma has been cited as being associated with olive root rots in Greece (1). Unidentified species of Pythium and Phytophthora have also been associated with olive tree root rots in the United States. However, the status of P. megasperma and Pythium spp. as olive tree root pathogens has remained unclear. Following a 5-year period of severe drought in southern Spain, autumn-winter rainfall rates in 1996 to 1997 steadily increased in both quantity and frequency. Under these unusually wet conditions, olive trees remained waterlogged for several months. During this period, we observed foliar wilting, dieback, and death of young trees, and later found extensive root necrosis. In 46 of 49 affected plantations surveyed, P. megasperma was consistently isolated from the rotted rootlets, particularly in young (<1- to 10-year-old trees) plantations. This fungus was not detected on plant material affected by damping-off from several Spanish olive tree nurseries. The opposite situation occurred with P. irregulare. This species was not associated with rotted rootlets in the field. In contrast, it was consistently isolated from necrotic rootlets from young olive plants affected by damping-off. These plants were grown in a sand-lime-peat soil mixture under greenhouse conditions and showed foliar wilting and extensive necrosis of the root systems. Pathogenicity tests were conducted with several isolates of P. megasperma and P. irregulare on 6-month-old rooted cuttings of olive, under both weekly watering and waterlogged conditions. Under waterlogged conditions, both fungal species produced extensive root necrosis 2 weeks after inoculation that resulted in wilting of the aerial parts and rapid plant death. Waterlogged control plants remained without foliar symptoms but a low degree of root necrosis was recorded. In addition, under weekly watering conditions, plants inoculated with either species showed some degree of root rot but foliar symptoms were not evident. No differences in pathogenicity were observed within the Phytophthora or Pythium isolates. Reference: (1) H. Kouyeas and A. Chitzanidis. Ann. Inst. Phytopathol. Benaki 8:175, 1968.

Detection of Pseudomonas syringae pv. Savastanoi, causal agent of olive tuberculosis in two regions of Western Algeria (Ain Témouchent and Sig)

2019 ◽  
Vol 9 (2) ◽  
pp. 64-71
Author(s):  
Benyoub Kheira ◽  
Kacem Mourad ◽  
Kaid-Harche Meriem
Keyword(s):  
Pseudomonas Syringae ◽  
Olive Tree ◽  
Causal Agent ◽  
Biochemical Tests ◽  
Node Disease ◽  
Different Temperatures ◽  
Leaf Level ◽  
Western Algeria ◽  
Olive Trees ◽  
Tree Leaf

The present study on olive tuberculosis commenced by isolating bacteria of the genus Pseudomonas from the soils and necrosis of collected olive trees. A total of 180 samples were used in this study: (100) rhizospheric soil samples: (60) samples at the region of Ain Témouchent and (40) at the region of Sig in western of Algeria. In total, (80) galls were collected (40) at branch level and (40) galls at olive tree leaf (level). The isolates were identified by microbiological (macroscopic and microscopic examination), physiological (growth in the presence of Salt (NaCl), growth at different pH values and growth at different temperatures) and biochemical methods (the LOPAT and Galeries Api 20 NE test to identify species of the Pseudomonas group and conventional biochemical tests to identify the subspecies P. syringae pv. Savastanoi).This allowed to identify 110 isolates of Pseudomonas (60 isolates of P. aeruginosa, 35 isolates of P. fluorescens and 15 isolates of P. syringae pv Savastanoi the causal agent of olive node disease) which are now part of the collection of Pseudomonas bacteria of the laboratory of the Biotechnology Department (USTO-MB). The selection of technological performance isolates useful for our agriculture could solve phytopathological problems and finally constitute a collection of the bacteria preserved.

scholarly journals Delineation of Tree Patches in a Mangrove-Marsh Transition Zone by Watershed Segmentation of Aerial Photographs

2020 ◽  
Vol 12 (13) ◽  
pp. 2086
Author(s):  
Himadri Biswas ◽  
Keqi Zhang ◽  
Michael S. Ross ◽  
Daniel Gann
Keyword(s):  
Vegetation Index ◽  
Vegetation Indices ◽  
Aerial Photographs ◽  
Watershed Segmentation ◽  
Marsh Vegetation ◽  
Tree Detection ◽  
Object Based ◽  
Segmented Images ◽  
Individual Trees ◽  
True Color

Mangrove migration, or transgression in response to global climatic changes or sea-level rise, is a slow process; to capture it, understanding both the present distribution of mangroves at individual patch (single- or clumped trees) scale, and their rates of change are essential. In this study, a new method was developed to delineate individual patches and to estimate mangrove cover from very high-resolution (0.08 m spatial resolution) true color (Red (R), Green (G), and Blue (B) spectral channels) aerial photography. The method utilizes marker-based watershed segmentation, where markers are detected using a vegetation index and Otsu’s automatic thresholding. Fourteen commonly used vegetation indices were tested, and shadows were removed from the segmented images to determine their effect on the accuracy of tree detection, cover estimation, and patch delineation. According to point-based accuracy analysis, we obtained adjusted overall accuracies >90% in tree detection using seven vegetation indices. Likewise, using an object-based approach, the highest overlap accuracy between predicted and reference data was 95%. The vegetation index Excess Green (ExG) without shadow removal produced the most accurate mangrove maps by separating tree patches from shadows and background marsh vegetation and detecting more individual trees. The method provides high precision delineation of mangrove trees and patches, and the opportunity to analyze mangrove migration patterns at the scale of isolated individuals and patches.

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