scholarly journals Modelling and Comparing Shading Effects of 3D Tree Structures with Virtual Leaves

2021 ◽  
Vol 13 (3) ◽  
pp. 532 ◽  
Author(s):  
Rafael Bohn Reckziegel ◽  
Elena Larysch ◽  
Jonathan P. Sheppard ◽  
Hans-Peter Kahle ◽  
Christopher Morhart
Keyword(s):  
Prunus Avium ◽  
Agricultural Land ◽  
Laser Scanner ◽  
Agroforestry Systems ◽  
Hemispherical Photography ◽  
Wild Cherry ◽  
Tree Structures ◽  
3D Data ◽  
Shading Effects ◽  
Cherry Trees

Reduced solar radiation brought about by trees on agricultural land can both positively and negatively affect crop growth. For a better understanding of this issue, we aim for an improved simulation of the shade cast by trees in agroforestry systems and a precise estimation of insolation reduction. We present a leaf creation algorithm to generate realistic leaves to be placed upon quantitative structure models (QSMs) of real trees. Further, we couple it with an enhanced approach of a 3D model capable of quantifying shading effects of a tree, at a high temporal and spatial resolution. Hence, 3D data derived from wild cherry trees (Prunus avium L.) generated by terrestrial laser scanner technology formed a basis for the tree reconstruction, and served as leaf-off mode. Two leaf-on modes were simulated: realistic leaves, fed with leaf data from wild cherry trees; and ellipsoidal leaves, having ellipsoids as leaf-replacement. For comparison, we assessed the shading effects using hemispherical photography as an alternative method. Results showed that insolation reduction was higher using realistic leaves, and that the shaded area was greater in size than with the ellipsoidal leaves or leaf-off conditions. All shading effects were similarly distributed on the ground, with the exception of those derived through hemispherical photography, which were greater in size, but with less insolation reduction than realistic leaves. The main achievements of this study are: the enhancement of the leaf-on mode for QSMs with realistic leaves, the updates of the shadow model, and the comparison of shading effects. We provide evidence that the inclusion of realistic leaves with precise 3D data might be fundamental to accurately model the shading effects of trees.

scholarly journals Sudden Phytophthora Dieback of Wild Cherry Trees in Northwest Hungary

2016 ◽  
Vol 12 (2) ◽  
pp. 117-124
Author(s):  
Judit Sárándi-Kovács ◽  
László Nagy ◽  
Ferenc Lakatos ◽  
György Sipos
Keyword(s):  
Prunus Avium ◽  
Deciduous Forest ◽  
Flood Plain ◽  
Phytophthora Species ◽  
Soil Conditions ◽  
Wild Cherry ◽  
Plain Area ◽  
Phytophthora Spp ◽  
Mixed Deciduous Forest ◽  
Cherry Trees

Abstract During a regular survey of declining forests in 2011, sudden dieback symptoms were observed on scattered wild cherry trees (Prunus avium) in a mixed deciduous forest stand, located in the flood plain area of the Rába River, in northwest Hungary. In this study, we correlated both soil conditions and presence of Phytophthora spp. to dieback of cherry trees. Two Phytophthora species, P. polonica and P. plurivora, were isolated from the rhizosphere soil of the dying trees. By contrast, only P. polonica was recovered from the necrotic tissues of symptomatic roots. Stem and root inoculation tests on cherry seedlings showed pathogenicity of both species, although P. polonica proved to be more virulent. This is the first report of natural infections of P. polonica.

scholarly journals Growth reaction of young wild cherry (Prunus aviumL.) trees to pruning

2008 ◽  
Vol 53 (No. 12) ◽  
pp. 555-560 ◽  
Author(s):  
I. Kupka
Keyword(s):  
Prunus Avium ◽  
Height Growth ◽  
Control Plot ◽  
Diameter Growth ◽  
Good Growth ◽  
Shadow Zone ◽  
Wild Cherry ◽  
Bottom Part ◽  
Growth Reaction ◽  
Cherry Trees

A large crown is one of the most important prerequisites for the good growth of a tree and therefore the crown could be called an engine of increment. The care for a large crown brings a decrease in the bole value at the same time as it makes large branches and later knots on it. Pruning is a possible solution of these two contradictions. Young wild cherry trees were pruned in three different ways: (<I>i</I>) half of the crown left, (<I>ii</I>) one quarter of the crown left and (<I>iii</I>) control, i.e. no pruning. The results show that height growth was not influenced by pruning while diameter growth was significantly affected. The crown reduction to a half means 10% less in diameter growth within a 5-year period after pruning. The crown reduction to one quarter of the crown means only two thirds of ‘full’ diameter growth on the control plot. The data suggest that the pruning of young wild cherry trees should be done moderately (more than a half of the crown should be left) and pruning should be done when the bottom part of the crown is in the shadow zone of the crown layer, not earlier.

scholarly journals Virtual pruning of 3D trees as a tool for managing shading effects in agroforestry systems

2021 ◽  
Author(s):  
Rafael Bohn Reckziegel ◽  
Jonathan P. Sheppard ◽  
Hans-Peter Kahle ◽  
Elena Larysch ◽  
Heinrich Spiecker ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Management Strategies ◽  
Ground Level ◽  
Agroforestry Systems ◽  
Spatiotemporal Resolution ◽  
Tree Structures ◽  
Woody Perennials ◽  
Crown Structure ◽  
Light Management ◽  
Shading Effects

AbstractLight is a limiting resource for crops within integrated land use systems especially those including woody perennials. The amount of available light at ground level can be modified by artificially pruning the overstory. Aiming to increase the understanding of light management strategies, we simulated the pruning of wild cherry trees and compared the shading effects of the resulting tree structures over a complete growing season, with fine spatiotemporal resolution. Original 3D-tree structures were retrieved employing terrestrial laser scanning and quantitative structure models, and subjected to two pruning treatments at low and high intensities. By using the ‘shadow model’, the analogous tree structures created diverse shaded scenarios varying in size and intensity of insolation reduction. Conventional pruning treatments reduced the crown structure to the uppermost portion of the tree bole, reducing the shading effects, and thus, shrinking the shaded area on the ground by up to 38%, together with the shading intensity. As an alternative, the selective removal of branches reduced the shading effects, while keeping a more similar spatial distribution compared to the unpruned tree. Hence, the virtual pruning of tree structures can support designing and selecting adequate tending operations for the management of light distribution in agroforestry systems. The evidence assembled in this study is highly relevant for agroecosystems and can be strategically used for maintaining, planning and designing integrated tree-crop agricultural systems.

scholarly journals The root-plant ratio changes in the first growing periods of wild cherry (Prunus avium L.) plantations

2008 ◽  
Vol 53 (No. 3) ◽  
pp. 113-118
Author(s):  
I. Kupka
Keyword(s):  
Growth Performance ◽  
Root System ◽  
Prunus Avium ◽  
Fine Root ◽  
Wild Cherry ◽  
Planting Stock Quality ◽  
System Data ◽  
Allometric Analysis ◽  
Efficiency Data ◽  
Cherry Trees

The root-plant ratio is one of the important parameters for planting stock quality. We suppose that the ratio is one of the driving variables for the growth performance of new plantation in the forest. The study summarises data on the volume of major parts of 4 years old wild cherry trees. An allometric analysis of different parts of plants in relation to the growth performance of wild cherry trees was done. The results show a close positive relationship between the volume of the whole root system and aboveground biomass. The same is true of the fine root proportion in the root system. Data also document that the efficiency of root system is not decreasing during the root development - at least in the investigated period. The same results were obtained for fine root efficiency. Data confirm the importance of the root-plant ratio for the growth performance of new plantation in the forest provided that harmful factors are not at a limiting level.

scholarly journals Agroforestry Systems of the Tehuacán-Cuicatlán Valley: Land Use for Biocultural Diversity Conservation

Land ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 24
Author(s):  
Mariana Vallejo ◽  
M. Isabel Ramírez ◽  
Alejandro Reyes-González ◽  
Jairo López-Sánchez ◽  
Alejandro Casas
Keyword(s):  
Land Use ◽  
Agricultural Land ◽  
Agroforestry Systems ◽  
World Heritage Site ◽  
Biocultural Diversity ◽  
Semiarid Region ◽  
Agricultural Land Use ◽  
Visual Interpretation ◽  
Natural Ecosystems ◽  
Human Settlements

The Tehuacán-Cuicatlán Valley, Mexico, is the semiarid region with the richest biodiversity of North America and was recently recognized as a UNESCO's World Heritage site. Original agricultural practices remain to this day in agroforestry systems (AFS), which are expressions of high biocultural diversity. However, local people and researchers perceive a progressive decline both in natural ecosystems and AFS. To assess changes in location and extent of agricultural land use, we carried out a visual interpretation of very-high resolution imagery and field work, through which we identified AFS and conventional agricultural systems (CAS) from 1995 to 2003 and 2012. We analyzed five communities, representative of three main ecological and agricultural zones of the region. We assessed agricultural land use changes in relation to conspicuous landscape features (relief, rivers, roads, and human settlements). We found that natural ecosystems cover more than 85% of the territory in each community, and AFS represent 51% of all agricultural land. Establishment and permanence of agricultural lands were strongly influenced by gentle slopes and the existence of roads. Contrary to what we expected, we recorded agricultural areas being abandoned, thus favoring the regeneration of natural ecosystems, as well as a 9% increase of AFS over CAS. Agriculture is concentrated near human settlements. Most of the studied territories are meant to preserve natural ecosystems, and traditional AFS practices are being recovered for biocultural conservation.

scholarly journals Potential of UAS-Based Remote Sensing for Estimating Tree Water Status and Yield in Sweet Cherry Trees

2020 ◽  
Vol 12 (15) ◽  
pp. 2359
Author(s):  
Víctor Blanco ◽  
Pedro José Blaya-Ros ◽  
Cristina Castillo ◽  
Fulgencio Soto-Vallés ◽  
Roque Torres-Sánchez ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Deficit Irrigation ◽  
Vegetation Index ◽  
Sweet Cherry ◽  
Prunus Avium ◽  
Water Status ◽  
Control Treatment ◽  
Stem Water Potential ◽  
Irrigation Treatments ◽  
Cherry Trees

The present work aims to assess the usefulness of five vegetation indices (VI) derived from multispectral UAS imagery to capture the effects of deficit irrigation on the canopy structure of sweet cherry trees (Prunus avium L.) in southeastern Spain. Three irrigation treatments were assayed, a control treatment and two regulated deficit irrigation treatments. Four airborne flights were carried out during two consecutive seasons; to compare the results of the remote sensing VI, the conventional and continuous water status indicators commonly used to manage sweet cherry tree irrigation were measured, including midday stem water potential (Ψs) and maximum daily shrinkage (MDS). Simple regression between individual VIs and Ψs or MDS found stronger relationships in postharvest than in preharvest. Thus, the normalized difference vegetation index (NDVI), resulted in the strongest relationship with Ψs (r2 = 0.67) and MDS (r2 = 0.45), followed by the normalized difference red edge (NDRE). The sensitivity analysis identified the optimal soil adjusted vegetation index (OSAVI) as the VI with the highest coefficient of variation in postharvest and the difference vegetation index (DVI) in preharvest. A new index is proposed, the transformed red range vegetation index (TRRVI), which was the only VI able to statistically identify a slight water deficit applied in preharvest. The combination of the VIs studied was used in two machine learning models, decision tree and artificial neural networks, to estimate the extra labor needed for harvesting and the sweet cherry yield.

INSECT TRANSMISSION OF THE VIRUS CAUSING LITTLE CHERRY DISEASE

1960 ◽  
Vol 40 (4) ◽  
pp. 707-712 ◽  
Author(s):  
W. H. A. Wilde
Keyword(s):  
Sweet Cherry ◽  
Prunus Avium ◽  
Virus Disease ◽  
Insect Transmission ◽  
Prunus Avium L ◽  
Cherry Trees

Little cherry virus disease of sweet cherry (Prunus avium L.) was transmitted under screenhouse conditions by 3 species of leafhoppers (Homoptera: Cicadellidae) out of 24 species tested. Macrosteles fascifrons (Stal), the 6-spotted leafhopper, transmitted the disease in seven tests; Scaphytopius acutus (Say), the sharp-nosed leafhopper, transmitted it once; and Psammotettix lividellus (Zett.) transmitted it once. The transmissions were made from diseased sweet cherry trees of the variety Lambert to indicators of the varieties Star or Sam. With the exception of 1 transmission, 2 to 4 years were necessary following inoculation for unmistakable expression of symptoms in the indicators. M. fascifrons was also implicated in 18 successful transmissions to mature sweet cherry trees grown in the open.

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