An Estimate Of Plant Biomass And Assessment Of The Ecological Balance Capacity Of The Hanoi Green Corridor.pdf

VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY HOANG DINH VIET AN ESTIMATE OF PLANT BIOMASS AND ASSESSMENT OF THE ECOLOGICAL BALANCE CAPACITY OF THE HANOI GREEN CORRIDOR MASTER’S THESIS H[.]

VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY HOANG DINH VIET AN ESTIMATE OF PLANT BIOMASS AND ASSESSMENT OF THE ECOLOGICAL BALANCE CAPACITY OF THE HANOI GREEN CORRIDOR MASTER’S THESIS Hanoi, 2019 VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY HOANG DINH VIET AN ESTIMATE OF PLANT BIOMASS AND ASSESSMENT OF THE ECOLOGICAL BALANCE CAPACITY OF THE HANOI GREEN CORRIDOR MAJOR: MASTER IN INFRASTRUCTURE ENGINEERING CODE: Dr LE QUYNH CHI Hanoi, 2019 ANNEX two LIST OF FORMS FOR MANAGEME TABLE OF CONTENTS TABLE OF CONTENTS i LIST OF FIGURES iv LIST OF TABLES v LIST OF ABBREVIATIONS vi ACKNOWLEDGMENT vii INTRODUCTION 1 The necessity of the research topic Contributions and objectives of the thesis Methodology Thesis’s structure 5 Terms and concepts 5.1 The concepts of Green space, Green corridor, Greenbelt are recognized by the world 5.2 Concept of GS, GC, GB according to the Master Plan of Hanoi Capital in 2011 5.3 Concept of plant biomass CHAPTER 1: LITERATURE REVIEW 1.1 Overview and assessing the effectiveness of the green space models outside urban centers in the world 1.1.1 London’s metropolitan greenbelt, Britain 1.1.2 Beijing area’s Greenbelt, China 1.1.3 Seoul’s greenbelt, Korea 11 1.1.4 Tokyo’s greenbelt, Japan 12 1.2 Overview of research related to the topic 15 1.2.1 The role of carbon pools in climate change mitigation 15 1.2.2 Studies on estimating urban plant biomass 17 1.2.3 Studies on biomass estimation using remote sensing data 21 CHAPTER 2: METHODOLOGY AND DATABASE 22 2.1 Research content 22 i 2.2 Methodologies 22 2.2.1 Perspective anh methodologies 22 2.2.1.1 Perspective on environmental science 22 2.2.1.2 Perspective on biomass research and ground carbon accumulation based on satellite image data 22 2.2.1.3 The theoretical basis of LiDAR 23 2.2.2 Research method diagram 25 2.3 Process of calculation 26 2.3.1 Site description 26 2.3.2 Data sources of satellite image 27 2.3.2.1 Landsat satellite images data 27 2.3.2.2 LiDAR data products 29 2.3.2 Identification of green corridor vegetation using GIS 30 2.3.3 Segments canopy according base on height 32 2.3.4 Plant biomass estimate base on height of canopy 33 2.2 Methodology and sources of greenhouse gas inventory data 34 2.3 Land use/land cover (LULC) of Hanoi’ Green Corridor 35 CHAPTER 3: FIDDING AND DISCUSSION 37 3.1 Fidding 37 3.1.1 Results of estimate plant biomass in Hanoi Green Corridor (No consider land use change) 37 3.1.2 Change in LULC of Hanoi’s Green Corridor 39 3.2 Discussion 42 3.2.1 Hanoi Assess the 𝐶𝑂2 balance capacity in the air of Green Corridor 42 3.2.1.1 Results of estimating 𝐶𝑂2 absorption capacity of GC compared to total of Hanoi 𝐶𝑂2 emission 42 3.2.1.2 Comparison of 𝐶𝑂2 absorption capacity of Hanoi GC with similar models in the world 42 3.2.2 Enhance the ecological balance ability of the Green Corridor in Hanoi 43 ii 3.2.3 Assess the ecological balance of the Green Corridor in the future 44 CHAPTER 4: CONCLUSION AND RECOMMENDATIONS 46 4.1 Conclusion 46 4.1.1 Thesis’s structure 46 4.1.2 Limitations of thesis 47 4.1.2.1 Methodology 47 4.1.2.2 Database 47 4.2 Recommendations 48 REFERENCES 50 iii LIST OF FIGURES Fig 1: Green Corridor Functional Map Fig 1.1: London’s metropolitan greenbelt Fig 1.2 a, b: Beijing’s green belt (a), Beijing’s green belt in phase II 10 Fig 1.3: Seoul’s greenbelt 11 Fig 1.4 a, b: Tokyo’s greenbelt in planning project 1958 (a), Tokyo’s green space in planning project 1968 13 Fig 1.5: Carbon Cycle 17 Fig 2.1: LiDAR working principle 24 Fig 2.2 Products of LiDAR technology 25 Fig 2.3 Research method diagram 26 Fig 2.4: Location of the Green Corridor in Hanoi 27 Fig 2.5: Landsat images were taken on June 4, 2016 29 Fig 2.6: nDSM model in the Green Corridor area 30 Fig 2.7 a,b,c: NDVI map 2015, 2016, 2019 31 Fig 3.1 a,b: Biomass map of Hanoi’s Green Corridor in 2015, 2016 39 Fig 3.2 a,b,c : Change in LULC of Hanoi’s Green Corridor in 2015, 2016, 2019 41 Fig 3.3: Change in LULC of Hanoi’s Green Corridor in 2015, 2016, 2019 diagram 44 Fig 3.4: Relationship between propotion of tree land and amount of 𝐶𝑂2 absorption 45 Fig 4.1: Compare biomass estimation results by using satellite images of different resolutions 48 iv LIST OF TABLES Table 1.1: The goal of developing GS outside urban centers in some cities in the world 14 Table 1.2: location and scale of green space outside urban centers in some cities in the world 15 Table 2.1: Landsat images used in the thesis 28 Table 2.2: Statistics of total pixels for each type of tree in the GC area in 2015 32 Table 2.3: Statistics of total pixels for each type of tree in the GC area in 2016 33 Table 2.4: Statistics of total pixels for each type of tree in the GC area in 2019 33 Table 2.5: Statistics on 𝐶𝑂2 emissions of Hanoi in 2015 35 Table 2.6: Characteristics of land types classified by IPCC 2006 36 Table 3.1: Biomass value estimated and 𝐶𝑂2 in 2015 38 Table 3.2: Biomass value estimated and 𝐶𝑂2 in 2016 38 Table 3.3: Biomass value estimated and 𝐶𝑂2 in 2019 39 Table 3.4: Summary table of LULC classification results 2015, 2016, 2019 40 Table 3.5: 𝐶𝑂2 absorption capacity in Hanoi’s GC, Seoul’s GB and Dakota’s GS 42 v LIST OF ABBREVIATIONS WWF-World Wildlife Fund IPCC - The Intergovernmental Panel on Climate Change AEBIOM - European Biomass Industry Association IPCC - The Intergovernmental Panel on Climate Change MNRE - Ministry of Natural Resources and Environment REDD+ - Deforestation and Forest Degradation (REDD+) VIAP - Vietnam Institute of Architecture and Urban and Rural Planning USGS - United States Geological Survey GSO- General Statistics Office of Vietnam UHI - Urban Heat Island phenomenon GIS - Geographic Information System LiDAR- Light Detection and Ranging nDSM - normalized Digital Surface Model NDVI - Normalized Difference Vegetation Index LULC – Land use, Land cover GHG- Greenhouse gas GC- Green Corridor GS- Green space GB- Greenbelt C - Carbon 𝐶𝑂2 - Carbon dioxide 𝐶𝑂2 e - Carbon dioxide equivalent vi ACKNOWLEDGMENT This master thesis has conducted in February 2019 At that time, I was still studying at Kanazawa University, Japan After months of internship in Japan, I returned to Vietnam to complete the thesis Under the guidance of Dr Le Quynh Chi, from National University of Civil Engineering (NUCE) Therefore, I would like to express my deep gratitude and special thanks to Dr Le Quynh Chi for her support, giving me the necessary guidance and valuable lessons to carry out my research I would like to give these first lines to acknowledge her contribution most respectfully I would like to send my best wishes and deepest gratitude to Professor Kato, Tokyo University and Prof Nguyen Dinh Duc, Vietnam National University, Hanoi and Dr Phan Le Binh, lecturer, JICA has long been an expert at VJU, Dr Nguyen Tien Dung, a lecturer for their careful and valuable support, which is extremely valuable for my research both in theory and in practice Moreover, I look forward to expressing my deep gratitude to Prof Zhenjiang SHEN, a very talented and humble person who has only facilitated my study and work in his Urban Planning Laboratory I also give my sincere thanks to the doctoral students, masters, and students at the laboratory who have helped me a lot in knowledge that very useful fot my thesis during my internship in Japan Last but least, my master thesis also a present to my parents for always being by my side Sincerely, Hoang Dinh Viet vii ABSTRACT The Green Corridor (GC) is a new concept of the Master planning of Hanoi to 2030, vision 2050 The role of the GC is to become an urban logistics area to preserve the landscape and ensure urban living environment In particular, balancing urban living environment is a very esential goal The GC accounts for 68% of Hanoi's natural land The tree land in the GC is the ideal carbon sink to assist the city reduce the nagative impact of Urban Heat Island (UHI), 𝐶𝑂2 balance in the air However, under the pressure of urbanization and the existence of urban, industrial development projects and other ongoing activities The area of trees in the Hanoi’s GC has been declining rapidly, which reduces the ability to absorb 𝐶𝑂2 that human activities discharge By applied the concept of plant biomass This thesis provides an approach through quantifying carbon contained in vegetation in the GC and the ability to balance 𝐶𝑂2 in the air of GC Combined with remote sensing images, which is currently the strongly tool to apply for estimating biomass in large scale and complex terrain like Hanoi city viii Location and scale: The ratio of the total area of urban areas accounts for 27.5% of the total natural land area, expanding the area of the area by stages The fourth and final phase, the total area of the GB is expanded to 247.6 km2, surrounding the new towns of Ansan in the southwest, close to the suburbs of Incheon, Anyang and Suwon The final result of the four stages, the total area of the GB is 1,566.8 km2, the farthest area of the rural up to 40 km from the city center (David N Bengston and Youn Yeo-Chang, 2004) (fig 1.3) Structure model: There is a single-layer GB structure, open spaces that surround the core city Functional components in the Seoul GB are diverse Including functional areas such as: river and lake areas scattered and cut through urban areas; Agriculture area in the year; Entertainment and tourism areas; Forest and hill areas In particular, forest accounts for the largest proportion 1.1.4 Tokyo’s greenbelt, Japan Development process: Japan's GB development can be divided into the following three main phases: The first period from 1932 to 1968: The definition of GB similar to the London area plan in 1935 The urban government put the GB concept into the Tokyo Regional Planning Project in 1958 The second period from 1968 to 1977: The new city planning law was issued, according to which GB has been replaced by the new concept: Area of urbanization control The third phase from 1977 to the present: The urban GB planning system was established and a master plan for the park and GS was built, whereby the main point in the stage is to build a system of "Green buffer "In some small areas (Andre Sorensen, 2001) Development objective: According to the Tokyo Regional plan of 1958, GB's goals are similar as London’s GB (1935) 12 Location and scale: According to the Tokyo Regional Planning proposal of 1958, Tokyo's GS consists of a large one GB area of 13,730 ha, 40 large parks with a total area of 1,695 and 591 small parks with a total area of The area is 6,741 (Andre Sorensen, 2001) Fig 1.4 a, b: Tokyo’s greenbelt in planning project 1958 (a), Tokyo’s green space in planning project 1968 Source: Nguyen, 2016 Structure model: There is a change of structure model from 1958 to 1968 In the Tokyo Regional Planning proposal in 1958: One-layer GB format, is the urban enclosed open spaces, intermingled between urban areas In the 1968 Tokyo Area Planning Adjustment proposal: GB was adapted to a Green Network structure, including a system of green points as urban parks (fig 1.4 a,b) 13 Table 1.1: The goal of developing GS outside urban centers in some cities in the world Target London Beijing environment,  support to protect  protect landscape rural areas  control the expansion of urban  boundaries  prevent the merger of  Seoul  Reserve land agricultural for land, trees and environmental water areas purposes separating  Secure satellite cities agricultural and core cities land fund control the  Restricting neighboring development Seoul urban towns of urban areas expansion into according to neighboring the planning cities such as and establish Incheon, boundaries Suwon and between Euijeongbu urban and rural areas Economy  Support urban  Ensuring regeneration by balanced encouraging the growth between use of bare land Seoul and the and other urban cities land types 14  Protect historical Cultural and cultural values Table 1.2: location and scale of green space outside urban centers in some cities in the world Source: Nguyen Van Tuyen, 2018 City London Beijing Seoul Tokyo Location Open space The first GB Open space Parks for the is between surrounds the intermingled entire ring road core urban in urban suburbs and 5, the area areas second GB is between ring road and Area 4860 𝑘𝑚2 1760 𝑘𝑚2 1566,8 𝑘𝑚2 137,3 𝑘𝑚2 Ratio 76.5% 10.4% 27.5% 6.3% compared to the total city area 1.2 Overview of research related to the topic 1.2.1 The role of carbon pools in climate change mitigation Carbon dioxide is a GHG that accounts for over 50% of the GHG composition The increased atmosphere of 𝐶𝑂2 is mainly due to burning fossil fuels (about 80 to 85%) and deforestation worldwide (Schneider, 1989; Hamburg et al., 15 1997) 𝐶𝑂2 in the atmosphere is estimated to increase by 2600 million tons per year (Sedjo, 1989) Plants act as a carbon sink by producing oxygen during photosynthesis and storing carbon in the form of biomass The amount of carbon stored in the tree changes over time as the plant grows, dies and decay 𝐶𝑂2 balance in the air in urban areas has become a major challenge for researchers and policies in efforts to resolve human-induced climate change Urban green trees play an important role in the global carbon cycle (fig 1.3) because they contribute 80% of the above ground biomass, 𝐶𝑂2 or GHG because it has a great impact on global climate change Since 1850, people have emitted about 480 billion tons of 𝐶𝑂2 into the atmosphere through fossil fuel burning and changing land use Human activity has caused an increase in atmospheric 𝐶𝑂2 levels and disrupted the global carbon cycle However, the carbon nature has a mechanism to be recalled and stored in isolated carbon pools such as forests and trees The Intergovernmental Panel on Climate Change (IPCC) identifies carbon pools in ecosystem biomass, namely aboveground biomass, underground biomass, litter, wood debris and organic matter in the soil Among all carbon pools, above-ground biomass accounts for the majority Many authors believe that carbon stocks account for 50% or 45% of the dry biomass of parts of plants and forest ecosystems that store about 72% of the earth's carbon weight on the earth (Malhi, 2002) According to a report by the World Wildlife Fund (WWF) and the European Biomass Industry Association (AEBIOM), biomass can reduce 𝐶𝑂2 emissions (the main gas that causes global warming) by nearly 1,000 tons/year - equivalent to the annual dispersion of Canada and Italy combined (Bauen et al., 2004) In the global carbon cycle, the amount of carbon stored in plants is about 2.5 billion tons, while the atmosphere only contains about 0.8 billion tons (Watson, 2000) 16 Fig 1.5: Carbon Cycle Source: https://ucanr.edu In general, the researchers are interested in the increase of 𝐶𝑂2 in the atmosphere, its effects on the environment and emphasize the role of greenery in reducing Urban Heat Island phenomenon (UHI) This suggests that the study of biomass, carbon storage capacity and 𝐶𝑂2 absorption of plants is essential, it is a scientific basis for planners and managers to assess the role of GC for Hanoi urban environment 1.2.2 Studies on estimating urban plant biomass Plant ecosystems can play an important role in mitigating the effects of climate change by reducing carbon dioxide in the atmosphere Liu's study (2012) quantifies the carbon storage of urban forests and assesses the actual role of 17 urban forests in reducing atmospheric 𝐶𝑂2 The study introduced a case study of urban forests in Shenyang, a strong industrialized city in northeastern China Carbon storage and sequestration is estimated by biomass equations, using field survey data and urban forest data obtained from high resolution QuickBird images The benefit of carbon storage and sequestration is converted by monetary values, as well as the role of urban forests in compensating for carbon emissions from fossil fuel burning Results showed that urban forests in Shenyang's third ring road area stored 337,000 tons of carbon (equivalent to 13.88 million USD), with a carbon sequestration rate of 29,000 tons/year (1.19 million USD) Carbon stored by urban forests is equal to 3.02% of annual carbon emissions from fossil fuel combustion and carbon sequestration can offset 0.26% of annual carbon emissions in Shenyang In addition, Liu's results indicate that carbon storage and sequestration rates vary between urban forest types and species composition and age structure These results can be used to help assess the actual role and potential of urban forests in reducing atmospheric 𝐶𝑂2 in Shenyang In addition, Liu has provided insight to decision makers and the public to better understand the role of urban forests and provide better management plans for urban forests According to the study of David J Nowak on carbon storage and isolation by urban greenery in America Green biomass has been quantified to assess the extent and role of urban trees related to urban heat islands Information on urban trees has been provided from 28 cities and states to determine the average carbon density per unit area of canopy This information is used for measurements of canopy cover on the study area to determine total urban forest carbon stocks and annual quarantine by state and country The total tree carbon stock density is 7.69 kg C/m2 on average and the average density of 0.28 kg C/m2/year Total tree carbon stocks in US urban areas (2005) are estimated at 18 643 million tons (worth US $ 50.5 billion; 95% CI, 597 million and 690 million tons) and estimated annual estimates 25.6 million tons (US $ 2.0 billion;% CI, 23.7 million to 27.4 million tons) A study by Jo (2011) quantified carbon emissions from energy consumption and carbon storage by GS for three cities in Korea: Chuncheon, Kangleung and Seoul Carbon emissions are estimated according to the guidelines for using carbon emission factors for fossil fuels Woody plants are the subject to calculate the amount of carbon stored and absorbed by applying the biomass equation and the annual growth level of the trees Annual carbon emissions are 370 t/ha/year in Kangleung, 472 t/ha/year in Chuncheon and 264 t/ha/year in Seoul The average carbon stock of woody trees ranged from 26.0 to 60.1 t/ha for natural land in the studied cities and from 4.7 to 7.2 t/ha for urban land The annual average carbon absorption capacity of woody trees ranges from 1.6 to 3.91 t/ha/year for natural land in the city and from 0.53 to 0.80t/ha/year for urban land There is no significant difference (95% confidence level) in carbon stocks and per hectare increase in urban land between cities Woody plants have stored carbon equivalent to 6.0 to 59.1% of total carbon emissions in cities and absorbed the total carbon emissions by 0.5 to 2.2% of the total annual 𝐶𝑂2 emissions The ability of trees to store carbon in Chuncheon and Kangleung is more efficient, where the natural land area is larger and the population density is lower than in Seoul Strategies to increase carbon storage and absorption by urban green space have been explored Recently, in Beijing City, Yujia Tang (2016) uses data from field surveys, using the results of tree growth and government statistics yearbook to estimate storage capacity and carbon isolation ability of street trees in Beijing The results show that carbon density and carbon sequestration rate in Beijing's urban street trees are equal to 1/3, 1/2 of the corresponding magnitude of non19 urban forests in China However, the total amount of streert trees carbon sequestration in urban districts of Beijing was 3.1 ± 1.8 Gg/ year (1Gg = 10^9 g) in 2014, equivalent to only about 0,2% of annual 𝐶𝑂2 equivalent (𝐶𝑂2 e) emissions from total energy consumption show a rather limited role in offset the overall artificial emissions in China In Vietnam, along with participating in the Reducing Emission from Deforestation and Forest Degradation (REDD+) program, scientists have conducted numerous studies to determine the amount of carbon accumulated in ecosystems and land use types to determine the carbon quotas in reducing emissions and obtaining financial resources from carbon-absorbing environmental services (Ministry of Agriculture and Rural Development (2011)) Although there have been many works, some guidelines for the investigation and determination of national carbon stocks, studies only stop evaluating the carbon sequestration capacity of forest land, but not much Determine the carbon stock of urban trees Therefore, this study was conducted primarily to determine the carbon stock of urban trees Currently, the world's new approach to climate change is to study climate change adaptation and adaptation measures that are not only global and regional, but also focused on violations.The local to propose measures to significantly reduce the amount of carbon in the atmosphere by using land, using land management technology to reduce greenhouse gases The Pham Quoc Trung study (2018) aims to assess the possibility of perennial trees carbon accumulation in Bo Trach district, Quang Binh province To accomplish that goal, the study combined the results of classification of Landsat remote sensing images with field survey data to determine biomass, accumulated carbon stocks of perennial trees in Bo Trach district Research results show that the area of perennial crops accounts for 11,362.62 ha, mainly rubber trees The biomass and carbon stocks on the image 20 of rubber trees in the standard plots have an average biomass value of 40.53 tons/ha, an average carbon value of 20.28 tons/ha Thus, through the studies of the authors in the world and Vietnam, the determination of biomass and carbon stocks of urban trees is a widely applied trend, providing scientific basis and creating cashew favorable conditions for the adjustment of land use planning in the future to improve the ability of carbon accumulation in the soil to limit climate change 1.2.3 Studies on biomass estimation using remote sensing data High-resolution urban biomass and vegetation maps are useful tools for planning architects and research teams seeking to minimize the impact of urbanization and UHI effects urban and GHG mitigation impacts Steve M.Ractiti (2014) applied high-resolution remote sensing images to create an urban trees biomass map, assessing the accuracy of scales in biomass estimation, comparing the results of achieved with lower resolution estimates in Boston City By method of overlapping satellite data layers (including Lidar data on tree height estimation) and field-based observations for mapping canopy cover and carbon storage of trees on the ground Space resolution ~ m The coverage of the average canopy was estimated to be 25.5 ± 1.5% and the carbon stock was 355 Gg (28.8 Mg C/ha) for the city The study of Ractiti (2014) proved that, the urban areas have considerable carbon stocks and recent advances in high-resolution remote sensing have the potential to improve urban character and vegetation management 21 CHAPTER 2: METHODOLOGY AND DATABASE 2.1 Research content Research on biomass and carbon storage using Lansat remote sensing image data, Lidar data and supporting software (ENVI, ArcGIS) Creating biomass mapping, carbon accumulation of Hanoi Green Corridor by remote sensing and GIS methods Create land use maps over the years by remote sensing data and GIS methods 2.2 Methodologies 2.2.1 Perspective anh methodologies 2.2.1.1 Perspective on environmental science Based on the biology of plants to absorb 𝐶𝑂2 to produce biomass (C6H12O6) and release oxygen through photosynthesis and only in plants can this ability The biomass and the amount of carbon accumulated in the reservoirs in the trees ecosystem are organic Therefore, biomass and carbon trees accumulation is generally based on this principle 2.2.1.2 Perspective on biomass research and ground carbon accumulation based on satellite image data In order to support the rapid and timely calculation of biomass, many countries in the world have conducted research to calculate the biomass reserves of remote sensing-based vegetation such as Landsat, SPOT, AVHRR NOAA, ALOS, There are many methods of estimating biomass from satellite images through values such as radiation coefficients, reflectivity, and standardized 22 indexes of different plants (The Normalized Difference Vegetation Index NDVI ) NDVI is calculated based on the difference of reflected near infrared light and red light on plants Because the leaves reflect strongly with near-infrared radiation, the leaves' chlorophyl strongly absorbs the red light of the radiation in the visible region NDVI is often used to estimate primary productivity as well as plant biomass as well as monitoring forests and plants The higher the value of NDVI (from -1 to 1), the stronger the photosynthetic activity (Rouse et al., 1973; Gamon et al., 1995; di Bella et al., 2004) Hanoi Green Corridor is known for its rich and diverse vegetation Due to the complex terrain, the calculation of biomass by manual method takes quite a long time and is outside the scope of the master thesis The thesis proposes a solution using Landsat satellite image with a resolution of 30m space and a LiDAR data product with a horizontal accuracy of 100 cm and a vertical direction of 15 cm to calculate indicators related to birth grade level Tải FULL (63 trang): https://bit.ly/3Qhs0N1 2.2.1.3 The theoretical basis of LiDAR Dự phòng: fb.com/TaiHo123doc.net LiDAR (Light Detection And Ranging), is a term for a new, active remote sensing technology, using lasers to survey objects remotely The data obtained by the system is a collection of laser reflecting point clouds from the object being investigated A typical LiDAR system is usually fixed on a suitable type of aircraft The working principle of the system is similar to other active remote sensing systems When the plane flies over the area under investigation, the laser sensor will emit laser beams towards the object, the laser signal receiver attached to the sensor will receive the reflected signal from the object The LiDAR system often uses scanned mirrors to examine objects in strips with the width of the data range specified by the scanning angle of the mirror The 23 density of data points obtained depends on many factors such as plane velocity, flight altitude, rotation level of the sweep The distance is determined by the calculation of laser travel time broadcast The received data points usually include the parameters of the 3-dimensional position of the object (X, Y, Z) and the response laser intensity The precise 3-dimensional position of the scanning device, the mirror rotation angle and the distance obtained by the set of points will then be used to calculate the 3-dimensional position of the points on the surface of the survey object The LiDAR system is often attached to navigation devices (GPS) and inertial identification devices (IMU/INS) and ground locator station (GPS Base station) to collect the full calibration parameters for data processing later Every second of the survey, LiDAR technology can help collect hundreds of thousands of data points with very high accuracy, so the product made from this data set is rated to be VERY accurate position (X, Y, Z) (+/- several centimeters to a few dozen centimeters) Fig 2.1: LiDAR working principle Source: https://www.yellowscan-lidar.com 24 Advantages of LiDAR remote sensing technology: With an average frequency of 5,000 to 33,000 rays per second, the resulting data allows mapping the topographic surface and canopy surface with a high density of data and high precision Some LiDAR systems also allow the reception of intermediate feedback signals (between the start and end signals) to allow the analysis of the object structure (canopy structure) Tải FULL (63 trang): https://bit.ly/3Qhs0N1 Dự phòng: fb.com/TaiHo123doc.net Fig 2.2 Products of LiDAR data Source: www.yellowscan-lidar.com 2.2.2 Research method diagram 25 Fig 2.3 Research method diagram 2.3 Process of calculation 2.3.1 Site description According to the “Master Planning Project of Hanoi to 2030, the vision of 2050” The Hanoi Green Corridor area has a total area of 68% of Hanoi's natural land (2,273.2 km2) Figure 2.4 depicts the location of the Green Corridor in Hanoi 26 6793624 ... AND ASSESSMENT OF THE ECOLOGICAL BALANCE CAPACITY OF THE HANOI GREEN CORRIDOR” using tools are plant biomass in the Green Corridor area of Hanoi The assessment of the ability to balance