Forest regeneration appraisal with large-scale aerial photographs

R. J. Hall; A. H. Aldred

doi:10.5558/tfc68142-1

Forest regeneration appraisal with large-scale aerial photographs

The Forestry Chronicle ◽

10.5558/tfc68142-1 ◽

1992 ◽

Vol 68 (1) ◽

pp. 142-150 ◽

Cited By ~ 14

Author(s):

R. J. Hall ◽

A. H. Aldred

Keyword(s):

Forest Regeneration ◽

Large Scale ◽

Field Survey ◽

Accuracy Assessment ◽

Survival Rates ◽

Coniferous Forest ◽

Aerial Photographs ◽

Survey Results ◽

Regression Techniques ◽

Two Stages

The operational feasibility of using large-scale aerial photographs to quantify coniferous forest stocking and regeneration density, was assessed over 6 cutovers with a 1,700 ha total area. The project involved two stages: one to pre-stratify cutover stocking levels using 1:10,000 general-coverage, colour photos; and the second to sample intensively, stocking and density using 1:500 large-scale photos. The accuracy, cost and practical problems in using large-scale sampling photos for regeneration assessment were determined. Accuracy assessment included detectability of young trees, species interpretation, and reliability of stocking and density measurements. Stocking estimates were on average, only five percent lower than field survey results but could be calibrated using regression techniques. Large differences between field survey and photo estimates of density in stems/ha suggested such counts should not be made from large-scale photos. Density count differences were attributable to seedlings occurring in dense patches or clumps where field counts were also difficult. If survey objectives and methods are carefully planned, large-scale photos can be a suitable tool for assessing and monitoring the stocking and survival rates of coniferous forest regeneration. Key words: Forest regeneration appraisal, silviculture, inventory, sampling, large-scale photography.

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ACCURACY EVALUATION OF VARIOUS SATELLITE IMAGERY PRODUCTS FOR LARGE SCALE TOPOGRAPHIC MAPPING

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-5-105-2018 ◽

2018 ◽

Vol XLII-5 ◽

pp. 105-110

Author(s):

N. Gahlot ◽

M. Dhara ◽

G. Prusty

Keyword(s):

Large Scale ◽

Field Survey ◽

Accuracy Assessment ◽

Building Blocks ◽

Topographic Mapping ◽

Accuracy Evaluation ◽

Terrain Mapping ◽

Precise Mapping ◽

Mapping Scale ◽

Prime Source

Abstract. DEM and ortho-imageries are building blocks for topographic mapping and satellite imageries are prime source of data for inaccessible terrain. When the required mapping scale is of the order 10k or higher, the accuracy needed is also of higher order. It becomes imperative to evaluate the accuracy of available high resolution DEMs and corresponding imageries to provide quality products for mapping. The present study is encouraged by the fact that not every place of our earth is accessible, so an assessment of satellite data products is required for precise mapping. Here, the accuracy assessment has been carried out in terms of RMSE, SD, CE90 and LE90 of various products viz. Carosat-1, Cartosat-2E, Worldview-2 (WV), Vricon, Pleiades, ALOS-World-3D (AW3D) ASTER, SRTM with Yahoo image. GCPs acquired by DGPS field survey were used to evaluate the products. The results have demonstrated that Vricon 0.5m ortho-image provides the best RMSE (3.42) and CE90 (4.65); however, WV and Vricon DEM turns out to be best with RMSE of 2.20m and 2.90m respectively. Both products are suitable for large scale topographic mapping. The data can be used for inaccessible terrain where GCPs are not available. However, Cartosat-1 and Cartosat-2E can be used where good GCPs are available. The outcome of study can be used for planning of data suitability for scale variant mapping and inaccessible terrain mapping.

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Accuracy assessment of cadastral maps using high resolution aerial photos

MATEC Web of Conferences ◽

10.1051/matecconf/201816203025 ◽

2018 ◽

Vol 162 ◽

pp. 03025

Author(s):

Imzahim Alwan ◽

Noor Hamed ◽

Haifaa Husien

Keyword(s):

Remote Sensing ◽

Large Scale ◽

Accuracy Assessment ◽

Aerial Photographs ◽

Aerial Photos ◽

Existing Structures ◽

Cadastral Maps ◽

Base Reference ◽

Ownership Of Land ◽

Metric Scale

A cadastral map is a map that shows the boundaries and ownership of land parcels. Some cadastral maps show additional details, such as survey district names, unique identifying numbers for parcels, certificate of title numbers, positions of existing structures, section or lot numbers and their respective areas, adjoining and adjacent street names, selected boundary dimensions and references to prior maps. In Iraq / Baghdad Governorate, the main problem is that the cadastral maps are georeferenced to a local geodetic datum known as Clark 1880 while the widely used reference system for navigation purpose (GPS and GNSS) and uses Word Geodetic System 1984 (WGS84) as a base reference datum. The objective of this paper is to produce a cadastral map with scale 1:500 (metric scale) by using aerial photographs 2009 with high ground spatial resolution 10 cm reference WGS84 system. The accuracy assessment for the cadastral maps updating approach to urban large scale cadastral maps (1:500-1:1000) was ± 0.115 meters; which complies with the American Social for Photogrammetry and Remote Sensing Standards (ASPRS).

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Pemetaan Sebaran Karamba Jaring Apung Berdasarkan Zona Dan Tingkat Skala Usaha Menggunakan Drone Di Waduk Riam Kanan Provinsi Kalimantan Selatan

EnviroScienteae ◽

10.20527/es.v16i2.9659 ◽

2020 ◽

Vol 16 (2) ◽

pp. 276

Author(s):

Muhammad Nur ◽

Muhammad Ahsin Rifa'i ◽

Rizmi Yunita ◽

Leila Ariyani Sofia

Keyword(s):

Large Scale ◽

Field Survey ◽

Survey Methods ◽

Actual Data ◽

Aerial Photographs ◽

Small Scale ◽

Scale Level ◽

Medium Scale ◽

Cage Aquaculture ◽

Net Cage

Aquaculture is growing rapidly in Banjar District of Kalimantan Selatan Province, including on Riam Kanan Reservoir which is a center for floating net cage aquaculture. The increasing aquaculture on Riam Kanan Reservoir is not supported by adequate and actual data regarding the distribution, number of plots and number of fishery household (FHs) of floating net cage aquaculture. Complete, accurate and actual data is needed as one of the considerations in implementing sustainable aquaculture management policies. This study aims to map the distribution of floating net cages based on zones and business scale level, analyze the number of plots and the number of FHs of floating net cage aquaculture on Riam Kanan Reservoir. The study was conducted in July-October 2019 using 2 survey methods: a drone survey to collect aerial photographs and a field survey to identify the number of FHs and floating net cage plots based on business scale level. The results of aerial photography were analyzed using the Agisoft Metashape Professional and Arcgis 10.7 applications. Field survey data were analyzed using the Archgis 10.7 application and Microsoft Excel. The floating net cage is spread over 6 zones totaling 4,263 plots, consisting of criteria for small business scale 1,774 plots, medium scale 1,234 plots and large scale 1,255 plots. FHs of floating net cage aquaculture spread in 7 villages as many as 425 units with the criteria of 331 small scale business, 87 medium scale and 28 large scale. The plots and FHs of floating net cage aquaculture on Riam Kanan Reservoir has increased significantly over the past 4 years.

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The Determination of Heating Shapes and Locations for Triangle Heating

Journal of Manufacturing Science and Engineering ◽

10.1115/1.3090886 ◽

2009 ◽

Vol 131 (2) ◽

Cited By ~ 7

Author(s):

Young-Bum Kim ◽

Jung-Seo Park ◽

Jong-Gye Shin ◽

Chung-Min Hyun ◽

Kwang-Hee Ko

Keyword(s):

Field Survey ◽

Functional Relation ◽

Angular Distortion ◽

Thermal Forming ◽

Heating And Cooling ◽

Unit Triangle ◽

Survey Results ◽

Regression Techniques ◽

Residual Deformations

Thermal forming is a method to form a curved plate by inducing local shrinkage and angular distortion through heating and cooling. In this approach, two different methods are available: line heating and triangle heating. Among them, this paper discusses triangle heating and presents algorithms for determining heating shapes and locations. The heating shape is determined by using the in-plane strain distributions, which are calculated by nonlinear kinematics analysis between the designed and initial shapes, field survey results, and mechanics based on the neutral axis. To predict the angular distortion and shrinkage in various heating conditions, a functional relation of residual deformations is formulated. For the formulation, multivariate analysis and multiple regression techniques are used with data obtained from experiments of unit triangle heating and numerical analysis. Using the determined heating shapes and the functional relation for the residual deformations, a correct triangle heating position is determined by an algorithm, which can predict qualitatively correct angular distortion and shrinkage in the interior and quantitatively correct distortion values on the edge. Finally, analytic verification of the proposed method has been done by applying the method to a convex type plate used in the field. The proposed work can be used for automation of curved plate fabrication in the shipyards.

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Interference mitigation in point to point wireless sensor networks using LSP protocol and time division multiplexing approach

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189028 ◽

2020 ◽

Vol 39 (4) ◽

pp. 5449-5458

Author(s):

A. Arokiaraj Jovith ◽

S.V. Kasmir Raja ◽

A. Razia Sulthana

Keyword(s):

Energy Consumption ◽

Large Scale ◽

Control Parameter ◽

Interference Mitigation ◽

Wireless Sensor ◽

Point To Point ◽

A Minor ◽

Two Stages ◽

Time Division ◽

And Control

Interference in Wireless Sensor Network (WSN) predominantly affects the performance of the WSN. Energy consumption in WSN is one of the greatest concerns in the current generation. This work presents an approach for interference measurement and interference mitigation in point to point network. The nodes are distributed in the network and interference is measured by grouping the nodes in the region of a specific diameter. Hence this approach is scalable and isextended to large scale WSN. Interference is measured in two stages. In the first stage, interference is overcome by allocating time slots to the node stations in Time Division Multiple Access (TDMA) fashion. The node area is split into larger regions and smaller regions. The time slots are allocated to smaller regions in TDMA fashion. A TDMA based time slot allocation algorithm is proposed in this paper to enable reuse of timeslots with minimal interference between smaller regions. In the second stage, the network density and control parameter is introduced to reduce interference in a minor level within smaller node regions. The algorithm issimulated and the system is tested with varying control parameter. The node-level interference and the energy dissipation at nodes are captured by varying the node density of the network. The results indicate that the proposed approach measures the interference and mitigates with minimal energy consumption at nodes and with less overhead transmission.

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Classification of vegetation in Cucphuong National Park with the aim of large-scale mapping, Vietnam

Geobotanical mapping ◽

10.31111/geobotmap/1994-1995.64 ◽

1996 ◽

pp. 64-67 ◽

Cited By ~ 1

Author(s):

Nguen Nghia Thin ◽

Nguen Ba Thu ◽

Tran Van Thuy

Keyword(s):

National Park ◽

Large Scale ◽

Satellite Images ◽

Field Work ◽

Aerial Photographs ◽

Vegetation Map ◽

Dense Forest ◽

Broad Leaved Forest ◽

Leaved Forest

The tropical seasonal rainy evergreen broad-leaved forest vegetation of the Cucphoung National Park has been classified and the distribution of plant communities has been shown on the map using the relations of vegetation to geology, geomorphology and pedology. The method of vegetation mapping includes: 1) the identifying of vegetation types in the remote-sensed materials (aerial photographs and satellite images); 2) field work to compile the interpretation keys and to characterize all the communities of a study area; 3) compilation of the final vegetation map using the combined information. In the classification presented a number of different level vegetation units have been identified: formation classes (3), formation sub-classes (3), formation groups (3), formations (4), subformations (10) and communities (19). Communities have been taken as mapping units. So in the vegetation map of the National Park 19 vegetation categories has been shown altogether, among them 13 are natural primary communities, and 6 are the secondary, anthropogenic ones. The secondary succession goes through 3 main stages: grassland herbaceous xerophytic vegetation, xerophytic scrub, dense forest.

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Index maps for large-scale vertical black and white aerial photographs of the Hayward and Calaveras faults, California

Open-File Report ◽

10.3133/ofr79284 ◽

1979 ◽

Author(s):

Charles W. Hedel

Keyword(s):

Large Scale ◽

Aerial Photographs ◽

Black And White ◽

Index Maps

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Vibration characteristics of triple-gear-rotor system in compressed air energy storage under variable torque load

Science Progress ◽

10.1177/0036850420987058 ◽

2021 ◽

Vol 104 (1) ◽

pp. 003685042098705

Author(s):

Xinran Wang ◽

Yangli Zhu ◽

Wen Li ◽

Dongxu Hu ◽

Xuehui Zhang ◽

...

Keyword(s):

Large Scale ◽

Three Dimensional ◽

Element Model ◽

Rotor System ◽

Dynamic Responses ◽

System Response ◽

Rotating Speed ◽

Torque Load ◽

Set Up ◽

Two Stages

This paper focuses on the effects of the off-design operation of CAES on the dynamic characteristics of the triple-gear-rotor system. A finite element model of the system is set up with unbalanced excitations, torque load excitations, and backlash which lead to variations of tooth contact status. An experiment is carried out to verify the accuracy of the mathematical model. The results show that when the system is subjected to large-scale torque load lifting at a high rotating speed, it has two stages of relatively strong periodicity when the torque load is light, and of chaotic when the torque load is heavy, with the transition between the two states being relatively quick and violent. The analysis of the three-dimensional acceleration spectrum and the meshing force shows that the variation in the meshing state and the fluctuation of the meshing force is the basic reasons for the variation in the system response with the torque load. In addition, the three rotors in the triple-gear-rotor system studied show a strong similarity in the meshing states and meshing force fluctuations, which result in the similarity in the dynamic responses of the three rotors.

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Evaluating Plantation Forest vs. Natural Forest Regeneration for Biodiversity Enhancement in Hong Kong

Forests ◽

10.3390/f12050593 ◽

2021 ◽

Vol 12 (5) ◽

pp. 593

Author(s):

Janet E. Nichol ◽

Sawaid Abbas

Keyword(s):

Hong Kong ◽

Species Richness ◽

Forest Regeneration ◽

Forest Succession ◽

Natural Forest ◽

Plantation Forestry ◽

Aerial Photographs ◽

Continuous Increase ◽

Natural Forest Regeneration ◽

Spatio Temporal

Global trends predict a continuous increase in the proportion of forest occupied by plantations up to the end of the 21st century, while a dramatic loss of biodiversity is foreseen as a result of anthropogenic exploitation and climate change. This study compares the role and performance of plantation policies in Hong Kong, with natural regeneration of secondary forest, using detailed spatio-temporal data extracted from a previous study. The study extends over a 70-year period from 1945 to 2014 using aerial photographs and satellite images of five time periods to document spatio-temporal trends in plantation forestry and natural forest succession. Field data on species richness and woody biomass at different stages of forest succession are compared with available data from plantations in the same study area. Results indicate that plantation forests support relatively few native species in the understory, with much lower species richness than naturally regenerated forest, even after 6 to 7 decades. Time-sequential maps of habitat change show that natural forest succession from barren grassy hillsides, progressed at an annual rate of 7.8%, from only 0.2% of the landscape post WWII, to over 37% today. Plantation forestry on the other hand has been less successful, and has even acted as a barrier to natural forest regeneration, as mono-cultural plantations from the late 1960s to 1980s are still plantations today, whereas other similar areas have succeeded naturally to forest. The theory of plantations acting as a nurse crop for a woody native understory is not supported, as Pinus massoniana plantations, destroyed by two deadly nematodes during the 1970s, apparently had no woody understory, as they were seen to have reverted to grassland in 1989 and are still mainly grassland today.

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