Phenotyping Architecture Traits of Tree Species Using Remote Sensing Techniques

HighlightsTree canopy architecture traits are associated with its productivity and management.Understanding these traits is important for both precision agriculture and phenomics applications.Remote sensing platforms (satellite, UAV, etc.) and multiple approaches (SfM, LiDAR) have been used to assess these traits.3D reconstruction of tree canopies allows the measurement of tree height, crown area, and canopy volume.Abstract. Tree canopy architecture is associated with light use efficiency and thus productivity. Given the modern training systems in orchard tree fruit systems, modification of tree architecture is becoming important for easier management of crops (e.g., pruning, thinning, chemical application, harvesting, etc.) while maintaining fruit quality and quantity. Similarly, in forest environments, architecture can influence the competitiveness and balance between tree species in the ecosystem. This article reviews the literature related to sensing approaches used for assessing architecture traits and the factors that influence such evaluation processes. Digital imagery integrated with structure from motion analysis and both terrestrial and aerial light detection and ranging (LiDAR) systems have been commonly used. In addition, satellite imagery and other techniques have been explored. Some of the major findings and some critical considerations for such measurement methods are summarized here. Keywords: Canopy volume, LiDAR system, Structure from motion, Tree height, UAV.

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Design and Experiment of an Aerial Electrostatic Spraying System for Unmanned Agricultural Aircraft Systems

Applied Engineering in Agriculture ◽

10.13031/aea.14150 ◽

2020 ◽

Vol 36 (6) ◽

pp. 955-962

Author(s):

Shilin Wang ◽

Xue Li ◽

Hao Zhou ◽

Xiaolan Lv ◽

Weiguo Shen

Keyword(s):

Droplet Size ◽

Negative Electrode ◽

Tree Canopy ◽

List Type ◽

Specific Charge ◽

Chemical Application ◽

Electrostatic Spraying ◽

Aircraft Systems ◽

Aircraft System ◽

Pump Pressure

HighlightsA bipolar contact electrostatic spraying system is designed for an unmanned agricultural aircraft system.The electrostatic voltage does not affect the droplet size and relative span.The specific charge due to the negative electrode is higher than that due to the positive electrode.The droplets charged by the spraying system are more prone to be deposited on the underside of leaves.Abstract. Chemical application by unmanned agricultural aircraft systems (UAASs) has developed rapidly in China and other Asian countries due to their suitability to complex terrains, high working efficiency, and labor intensity reduction. To enhance spraying performance of unmanned aerial spraying systems (UASSs), an aerial electrostatic spraying system (AESS) was designed consisting of a lithium battery, electrostatic generator, positive and negative charging electrodes, tanks, pumps, and centrifugal atomizers. The AESS electrostatic voltage (EV) was adjusted from 15 to 35 kV, the atomizer rotation speed reached 9600 r/min, and the pump pressure ranged from 0.02 to 0.1 MPa. The AESS specific charge and droplet spectrum under water spraying was measured at different EVs. Results showed that the specific charge due to the negative electrostatic electrode was higher than that due to the positive electrostatic electrode. At a negative electrostatic electrode EV of 35 kV, its specific charge was 1.84 mC/kg. The negative and positive electrostatic electrode volume median diameters (VMDs) ranged from 81.39 to 84.04 µm and 86.8 to 88.80 µm, respectively, and no significant droplet size and relative span differences occurred between the different EVs for the same electrostatic electrode. The AESS was installed on single-rotor and multirotor UAASs for chemical application to pear trees. The results revealed that the electrostatic spray from the AESS has no effect on droplet deposition on the upper side of pear tree canopy leaves, while charged droplets can produce a wrap-around effect on the underside of the leaves, which promotes the adhesion of droplets on the underside of the leaves. The AESS is suitable for chemical application under aerial UAAS spraying. Keywords: Chemical application, Droplet spectrum, Deposition, Specific charge, Unmanned agricultural aircraft system.

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Growth and yield of clonal guavas in south-eastern Queensland

Australian Journal of Experimental Agriculture ◽

10.1071/ea9860619 ◽

1986 ◽

Vol 26 (5) ◽

pp. 619

Author(s):

KR Chapman ◽

B Paxton ◽

DH Maggs

Keyword(s):

Fruit Size ◽

Tree Height ◽

Tree Canopy ◽

Tree Size ◽

Growth And Yield ◽

Marketable Yield ◽

Cross Sectional ◽

South Eastern ◽

Canopy Volume ◽

Highly Correlated

Five processing guava clones (GA6- 1, GA7- 12, GA8-30, GA9-35, GA11-56) were tested over 3 cropping years at Nambour, in coastal south-eastern Queensland. Mean marketable yield for the first crop at 2 years of age was 45 kg/tree or 36.23 t/ha at a density of 805 trees/ha. GA11-56, the most acceptable clone for processing, also gave the highest marketable yields of 627, 71.65 and 72.53 t/ha for the first 3 crops. Yield per unit cross sectional area of trunk was a more simple and useful index of yield efficiency than more complex parameters including a fruitfulness index and multiple regressions with yield of north-south canopy spread, number of primary branches and combinations of these and trunk girth. Similarly, trunk - - girth provided at least as good an estimate of tree size as the vigour index. Tree dimension measurements which included east-west canopy spread, north-south canopy spread, tree height, stem height, number of primary branches, crown height, crown radius, tree canopy volume, canopy surface area and an index of crown weight provided no consistent indication of tree size. They were not highly correlated with either accumulated or final yield of the guava. The GA11-56 clone because of its yield, fruit size and other desirable processing characteristics was the only clone that could be recommended for commercial plantings.

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Impact of Eidolon helvum on roost trees on UENR campus

Journal of Energy and Natural Resource Management ◽

10.26796/jenrm.v2i0.43 ◽

2018 ◽

Vol 2 (2) ◽

pp. 44-50

Author(s):

E. Danquah

Keyword(s):

Tree Species ◽

Diversity Index ◽

Canopy Cover ◽

Basal Area ◽

Tree Height ◽

Tectona Grandis ◽

Tree Canopy ◽

Species Diversity Index ◽

Tree Canopy Cover ◽

Occupied Zone

Four sample plots, each of size 20m by 20m were systematically distributed in two strata (i.e. two plots in bat-occupied zone andthe remaining two plots in bat-unoccupied zone, to serve as control units). Using six (20m × 20m) sample plots each, basal area,canopy, and heights of trees with DBH 1m were measured. Fourteen individual trees were recorded in the bat-unoccupied zone,resulting in only seven tree species. On the other hand, 16 tree species, corresponding to a total of 25 trees were recorded in thebat occupied zone. Albizia zygia, Antiaris toxicaria, Azadiractha indicia, Holarrhena floribunda, Morinda lucinda, and Sterculiatragacantha were common to both zones. The Shannon Wiener species diversity index was found to be higher (H1=1.92) in batoccupied zones and lower (H1=1.45) in bat-unoccupied zone. Estimates of tree basal area and tree height were much higherin bat occupied zones compared to bat-unoccupied zones. (Mann-Whitney U test: U = 573.0, p < 0.05), tree basal area (U= 674.0, p < 0.05), tree height (U = 632.0, p < 0.05) and tree canopy cover (U = 329.0, p < 0.05). Holarrhena floribunda(0.34 m2/h) and Ceiba pentandra (0.22m2/ha) contributed the largest basal area (32.94% of the total basal area) whilst Sennasiamea (0.01m2/ha) and Tectona grandis (0.01m2/ha) yielded the smallest basal area (1.17%). In general, bats seem to greatlypatronize areas with higher densities of tall trees than relatively open areas with shorter trees.

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Planting in Metallized Reflective Mulch Did Not Significantly Benefit Development of New Hybrid Citrus Seedlings

HortScience ◽

10.21273/hortsci16248-21 ◽

2022 ◽

Vol 57 (2) ◽

pp. 200-201

Author(s):

Ed Stover ◽

Stephen Mayo ◽

Randall Driggers ◽

Robert C. Adair

Keyword(s):

Fruit Quality ◽

Tree Height ◽

Tree Canopy ◽

Soil Culture ◽

Department Of Agriculture ◽

Accelerate Growth ◽

Canopy Volume ◽

Current Resource ◽

Greenhouse Plant ◽

Liberibacter Asiaticus

The U.S. Department of Agriculture citrus scion breeding program is urgently working on developing huanglongbing (HLB; pathogen Candidatus Liberibacter asiaticus)-tolerant cultivars with excellent fruit quality and productivity when HLB-affected. The slow process of assessing new citrus hybrids is a major impediment to delivery of these much-needed cultivars. We generate thousands of hybrids each year, germinate the seedlings, grow them for 2 years in the greenhouse, plant them at high density in a field where the disease HLB is abundant, grow them for 5 to 10 years, and make selections based on tree performance and fruit quality of these HLB-affected trees. Based on promising reports of accelerated citrus growth when grown in a metallized reflective mulch (MRM) system, we tested the hypothesis that the MRM system may accelerate growth and selection of new hybrid seedlings compared with conventional soil culture (CSC). In the MRM system, tree rows are covered with a layer of metallized plastic film and drip irrigation is installed beneath the plastic. In 2 years of analysis, tree canopy volume was significantly greater with MRM in 2020 (27% greater than CSC) but not in 2021, and MRM tree height was greater in 2021 (7% greater than CSC). Mortality was significantly greater with MRM in both 2020 and 2021(in 2021: 32% vs. 17% under CSC), and MRM trees had more chlorotic leaves. Because of staff limitations, plant debris and soil were not routinely cleared from MRM, thus diminishing any benefit from the reflective surface. Better maintenance might have resulted in more sustained evidence of MRM growth benefits. With the current resource availability, the MRM system does not appear to accelerate the assessment of hybrid seedling trees.

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Bases of Yield and Production Efficiency in Apple Orchard Systems

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.2.188 ◽

1991 ◽

Vol 116 (2) ◽

pp. 188-194 ◽

Cited By ~ 49

Author(s):

Terence L. Robinson ◽

Alan N. Lakso

Keyword(s):

Conversion Efficiency ◽

Production Efficiency ◽

Light Interception ◽

Apple Orchard ◽

Tree Canopy ◽

Canopy Architecture ◽

Cross Sectional ◽

Canopy Volume ◽

Total Light ◽

Slender Spindle

Bases of orchard productivity were evaluated in four 10-year-old apple orchard systems (`Empire' and `Redchief Delicious' Malus domestics Borkh. on slender spindle/M.9, Y-trellis/M.26, central leader/M.9/MM.111, and central leader/M.7a). Trunk cross-sectional areas (TCA), canopy dimension and volume, and light interception were measured. Canopy dimension and canopy volume were found to be relatively poor estimators of orchard light interception or yield, especially for the restricted canopy of the Y-trellis. TCA was correlated to both percentage of photosynthetically active radiation (PAR) intercepted and yields. Total light interception during the 7th to the 10th years showed the best correlation with yields of the different systems and explained most of the yield variations among systems. Average light interception was highest with the Y-trellis/M.26 system of both cultivars and approached 70% of available PAR with `Empire'. The higher light interception of this system was the result of canopy architecture that allowed the tree canopy to grow over the tractor alleys. The central leader/M.7a had the lowest light interception with both cultivars. The efficiency of converting light energy into fruit (conversion efficiency = fruit yield/light intercepted) was significantly higher for the Y-trellis/M.26 system than for the slender spindle/M.9 or central leader/M.9/MM.111 systems. The central leader/M.7a system bad the lowest conversion efficiency. An index of partitioning was calculated as the kilograms of fruit per square centimeter increase in TCA. The slender spindle/M.9 system had significantly higher partitioning index than the Y-trellis/M.26 or central leader/M.9/MM.111. The central leader/M.7a system had the lowest partitioning index. The higher conversion efficiency of the Y/M.26 system was not due to increased partitioning to the fruit; however, the basis for the greater efficiency is unknown. The poor conversion efficiency of the central leader/M.7a was mostly due to low partitioning to the fruit. The Y-trellis/M.26 system was found to be the most efficient in both intercepting PAR and converting that energy into fruit.

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Spray Volume, Canopy Density, and Other Factors Involved in Thinner Efficacy

HortScience ◽

10.21273/hortsci.33.3.553d ◽

1998 ◽

Vol 33 (3) ◽

pp. 553d-553

Author(s):

C.R. Unrath

Keyword(s):

Tree Height ◽

Tree Canopy ◽

Tree Size ◽

Water Volume ◽

Canopy Density ◽

The North ◽

Run Off ◽

Tree Canopies ◽

Average Water ◽

Water Volumes

Historically, most airblast chemical applications to apple orchards used a single “average” water volume, resulting in variability of coverage with tree size and also the greatest variable in chemical thinning. This coverage variability can be eliminated by properly quantifying the tree canopy, as tree row volume (TRV), and relating that volume to airblast water rate for adequate coverge. Maximum typical tree height, cross-row limb spread, and between-row spacing are used to quantify the TRV. Further refinement is achieved by adjusting the water volume for tree canopy density. The North Carolina TRV model allows a density adjustment from 0.7 gal/1000 ft3 of TRV for young, very open tree canopies to 1.0 gal/1000 ft3 of TRV for large, thick tree canopies to deliver a full dilute application for maximum water application (to the point of run-off). Most dilute pesticide applications use 70% of full dilute to approach the point of drip (pesticide dilute) to not waste chemicals and reduce non-target environmental exposure. From the “chemical load” (i.e., lb/acre) calculated for the pesticide dilute application, the proper chemical load for lower (concentrate) water volumes can be accurately determined. Another significant source of variability is thinner application response is spray distribution to various areas of the tree. This variability is related to tree configuration, light, levels, fruit set, and natural thinning vs. the need for chemical thinning. Required water delivery patterns are a function of tree size, form, spacing, and density, as well as sprayer design (no. of nozzles and fan size). The TRV model, density adjustments, and nozzle patterns to effectively hit the target for uniform crop load will be addressed.

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Estimating Forest Canopy Cover by Multiscale Remote Sensing in Northeast Jiangxi, China

Land ◽

10.3390/land10040433 ◽

2021 ◽

Vol 10 (4) ◽

pp. 433

Author(s):

Xiaolan Huang ◽

Weicheng Wu ◽

Tingting Shen ◽

Lifeng Xie ◽

Yaozu Qin ◽

...

Keyword(s):

Remote Sensing ◽

Large Scale ◽

Forest Canopy ◽

Canopy Cover ◽

Google Earth ◽

Tree Canopy ◽

Landsat Data ◽

High Resolution Data ◽

Modis Ndvi ◽

Tree Canopy Cover

This research was focused on estimation of tree canopy cover (CC) by multiscale remote sensing in south China. The key aim is to establish the relationship between CC and woody NDVI (NDVIW) or to build a CC-NDVIW model taking northeast Jiangxi as an example. Based on field CC measurements, this research used Google Earth as a complementary source to measure CC. In total, 63 sample plots of CC were created, among which 45 were applied for modeling and the remaining 18 were employed for verification. In order to ascertain the ratio R of NDVIW to the satellite observed NDVI, a 20-year time-series MODIS NDVI dataset was utilized for decomposition to obtain the NDVIW component, and then the ratio R was calculated with the equation R = (NDVIW/NDVI) *100%, respectively, for forest (CC >60%), medium woodland (CC = 25–60%) and sparse woodland (CC 1–25%). Landsat TM and OLI images that had been orthorectified by the provider USGS were atmospherically corrected using the COST model and used to derive NDVIL. R was multiplied for the NDVIL image to extract the woody NDVI (NDVIWL) from Landsat data for each of these plots. The 45 plots of CC data were linearly fitted to the NDVIWL, and a model with CC = 103.843 NDVIW + 6.157 (R2 = 0.881) was obtained. This equation was applied to predict CC at the 18 verification plots and a good agreement was found (R2 = 0.897). This validated CC-NDVIW model was further applied to the woody NDVI of forest, medium woodland and sparse woodland derived from Landsat data for regional CC estimation. An independent group of 24 measured plots was utilized for validation of the results, and an accuracy of 83.0% was obtained. Thence, the developed model has high predictivity and is suitable for large-scale estimation of CC using high-resolution data.

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Mapping the Urban Atmospheric Carbon Stock by LiDAR and WorldView-3 Data

Forests ◽

10.3390/f12060692 ◽

2021 ◽

Vol 12 (6) ◽

pp. 692

Author(s):

MD Abdul Mueed Choudhury ◽

Ernesto Marcheggiani ◽

Andrea Galli ◽

Giuseppe Modica ◽

Ben Somers

Keyword(s):

Remote Sensing ◽

Urban Area ◽

Tree Species ◽

Carbon Stock ◽

Dominant Species ◽

Remote Sensing Data ◽

Data Sources ◽

Lidar Data ◽

Urban Tree ◽

Sensing Data

Currently, the worsening impacts of urbanizations have been impelled to the importance of monitoring and management of existing urban trees, securing sustainable use of the available green spaces. Urban tree species identification and evaluation of their roles in atmospheric Carbon Stock (CS) are still among the prime concerns for city planners regarding initiating a convenient and easily adaptive urban green planning and management system. A detailed methodology on the urban tree carbon stock calibration and mapping was conducted in the urban area of Brussels, Belgium. A comparative analysis of the mapping outcomes was assessed to define the convenience and efficiency of two different remote sensing data sources, Light Detection and Ranging (LiDAR) and WorldView-3 (WV-3), in a unique urban area. The mapping results were validated against field estimated carbon stocks. At the initial stage, dominant tree species were identified and classified using the high-resolution WorldView3 image, leading to the final carbon stock mapping based on the dominant species. An object-based image analysis approach was employed to attain an overall accuracy (OA) of 71% during the classification of the dominant species. The field estimations of carbon stock for each plot were done utilizing an allometric model based on the field tree dendrometric data. Later based on the correlation among the field data and the variables (i.e., Normalized Difference Vegetation Index, NDVI and Crown Height Model, CHM) extracted from the available remote sensing data, the carbon stock mapping and validation had been done in a GIS environment. The calibrated NDVI and CHM had been used to compute possible carbon stock in either case of the WV-3 image and LiDAR data, respectively. A comparative discussion has been introduced to bring out the issues, especially for the developing countries, where WV-3 data could be a better solution over the hardly available LiDAR data. This study could assist city planners in understanding and deciding the applicability of remote sensing data sources based on their availability and the level of expediency, ensuring a sustainable urban green management system.

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Structure and Regeneration of Sal (Shorea robusta Gaertn. f.) Forests in Shiwalik Region of Kumaun Himalaya, India

Indian Journal of Forestry ◽

10.54207/bsmps1000-2017-0n83l0 ◽

2017 ◽

Vol 40 (1) ◽

pp. 1-8

Author(s):

Bhawna Adhikari ◽

◽

Bhawana Kapkoti ◽

Neelu Lodhiyal ◽

L.S. Lodhiyal ◽

...

Keyword(s):

Tree Species ◽

Basal Area ◽

Tree Canopy ◽

Canopy Density ◽

Kumaun Himalaya ◽

Shorea Robusta ◽

Canopy Trees ◽

Dense Forest ◽

Open Forest ◽

Sal Forest

Present study was carried out to assess the structure and regeneration of Sal forests in Shiwalik region of Kumaun Himalaya. Vegetation analysis and tree canopy density was determined by using quadrat and densitometer, respectively. Density of seedlings, saplings and trees was 490-14067, 37-1233, and 273-863 ind.ha-1 respectively. The basal area was 0.12-5.44 m2 ha-1 reported for saplings and 25.4-77.6 m2 ha-1 for trees. Regeneration of Sal was found good in Sal mixed dense forest followed by Sal open forest and Sal dense forest, respectively. Regeneration of Sal was assisted by the presence of associated tree species as well as the sufficient sunlight availability on ground due to adequate opening of canopy trees in Sal forest. Thus it is concluded that the density of tree canopy, sunlight availability and also associated tree species impacted the regeneration of Sal in the region.

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Measurement And Characterisation Of Tree Canopy Architecture

10.1109/igarss.1988.569582 ◽

2005 ◽

Author(s):

S.L. Ustins ◽

S. Martens ◽

J. Norman ◽

D. Goklhammer

Keyword(s):

Tree Canopy ◽

Canopy Architecture

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