Tài liệu The impact of land cover changes on land surface temperature in ho chi minh city based on landsat imagery

THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURAL AND FORESTRY NGUYEN CAM TU THE IMPACT OF LAND COVER CHANGES ON LAND SURFACE TEMPERATURE IN HO CHI MINH CITY BASED ON LANDSAT IMAGERY BACHELOR THESIS Study Mode Major Faculty Batch :Full-time :Environmental Science and Management :Advanced Education Program Office :2014 - 2018 Thai Nguyen, 25/09/2018 i Thai Nguyen University of Agricultural and Forestry Degree Program Bachelor of Environmental Science and Management Student name NGUYEN CAM TU Student ID DTN1453110150 Thesis Title The impact of Land Cover Changes on Land Surface Temperature in Ho Chi Minh City based on Landsat Imagery. Supervisor (s) Assoc. Prof. Tang-Huang Lin MSc. Nguyen Van Hieu Supervisor’s signature Abstract: Along with the growth of national and social economics ,the urban development is taking place strongly in Viet Nam during the past decades, especially in megacities. The assessment of land use changes is a very important issue among the impacts of urbanization ,serving as a foundation for land use planning.In this study , the multispectral and multi-temporal satellite imagery were used to investigate the impact of Land Cover Changes (LCCs) on Land Surface Temperature (LST) in Ho Chi Minh City(HCMC), Vietnam. Three sets of Landsat imageries covered a period of 20 years in HCMC from 1998 to 2017 are acquired for examining the impact of LCC , including Landsat 5 Thematic (TM) in 1998 and 2008 and Landsat 8 Operational Land Imager (OLI) in 2017. Supervised methodology is employed with maximum likelihood technique land cover classification. The land covers of the study area are categorized into four different classes namely vegetation, urban, bare soil and water. ii The results show that during the last two decades the area changing vegetation ,urban , bare soil have been decreased by 16.24% and 12.4% , while urban and water have been increased by 27.19% and 1.44% respectively. The most significant changes is the bare soil transited to urban type (20% in area) . As a consequence of the land cover changes , the LST was boosted up to 0.42 degree Celsius after 20 years . This study also indicates that the impacts of LCCs on LST was affected by the development of new urban city and the population growth which play an important role in the Land Cover Changes as well as Land Surface Temperature. Keywords: Number of pages: Ho Chi Minh City, Land Surface Temperature, Land Cover Changes 57 25/09/2018 Date of Submission: iii ACKNOWLEDGEMENT From bottom of my heart , I would like to express my deepest appreciation to Associate Professor Tang-Huang Lin who in spite of being extraordinary busy with his duties , took time out to hear , guide, keep me on the correct path and complete report during the time of conducting the research at Center for Space and Remote Sensing Research (CSRSR) of National Central University (NCU). I also wish to express my deep gratitude to MSc. Nguyen Van Hieu who gives me an opportunity , guidance and support me to complete thesis. For my friends in Taiwan, I would like to send my best wishes to all of you : Minh Nguyen, Chang Jui-Chung, Tzu-Ying Chen. Thank you for always listening to me and helping me to overcome the weakness and hardships during the time I conducted my internship in NCU. You are all made up my life in Taiwan more meaningful and those unforgettable moments will go along with me forever. I sincerely thank the additional members of CSRSR who have contributed to my work . Last but not least, I take this opportunity to record my sense of gratitude to my families and friends who encourage and backing me unceasingly. Thai Nguyen, 20/09/2018 Student Nguyen Cam Tu iv TABLE OF CONTENT List of Figures ....................................................................................................................... vi List of Tables ........................................................................................................................ vii List of Abbreviation .............................................................................................................. vii PART I. INTRODUCTION .................................................................................................. .1 1.1.Research rationale ........................................................................................................... .1 1.2.Investigate the study area ................................................................................................ .3 1.3. Statement of Problem ..................................................................................................... .4 1.4.Objectives of study .......................................................................................................... .5 1.5. Significance of study ...................................................................................................... .6 1.6 Limitation of Study ......................................................................................................... .6 PART II. LITERATURE REVIEW ..................................................................................... .7 2.1.Land Use/Cover Change .................................................................................................. 7 2.2.Land Surface Temperature ............................................................................................. 10 2.4 Land Cover Change and Land Surface Temperature in Vietnam3.Impact of Land Cover Change on Land Surface Temperature .................................................................................. 11 2.5 Related study on Land Cover Change and Land Surface Temperature over the world...13 PART III.METHODS ............................................................................................................ 16 3.1 Material and Data .......................................................................................................... 16 3.2 The objectives and the scope .......................................................................................... 17 3.3 Methodology. ................................................................................................................... 18 PART IV. RESULTS AND DISCUSSION ......................................................................... 31 4.1 Results of Land Cover Changes. ..................................................................................... 31 4.2 Change Detection ............................................................................................................ 34 4.3 Results of Land Surface Temperature ............................................................................. 44 v PART V.CONCLUSION .................................................................................................... 49 REFERENCES .................................................................................................................... 51 APPENDICES5 ..................................................................................................................... 55 vi LIST OF FIGURES Figure 1. The map of Study Area ............................................................................. 4 Figure 2. Methodology of the impact of LCC on LST ............................................. 18 Figure 3. Method for Pre-Processing of remote sensing data ................................... 19 Figure 4. Layer Stacked images of 1998(a), 2008(b) and 2017 (c) .......................... 22 Figure 5.Clip Area of Ho Chi Minh City for 1998,2008 and 2017 ........................... 23 Figure 6. Flow chart of Land Surface Temperature computation ............................. 26 Figure 7. Land Cover Change map of 1998,2008 and 2017 ..................................... 30 Figure 8. The percentage of area of each land cover changed in 1998-2017 ........... 31 Figure 9. Change Detection of HCMC from 1998-2017 ......................................... 33 Figure 10. The percentage of Land Cover Change from 1998-2017 ........................ 35 Figure 11. Brightness Temperature of 1998,2008 ,2017 band 10 and band 11 ........ 36 Figure 12. Normalized Difference Vegetation Index map for three diferrent year 1998,2008 and 2017 ................................................................................................... 38 Figure 13. Green Vegetation Fraction of 1998,2008 and 2017 ................................. 40 Figure 14. The Emissivity map for (a)1998, (b) 2008 and (c)2017 .......................... 41 Figure 15. Land Surface Temperature map of 1998,2008 and 2017 ......................... 43 Figure 16. The relationship between Land Cover Changes and the Mean of Land Surface Temperature in degree Celsius over two decades ( 1998-2017) ................... 46 vii LIST OF TABLE Table 1. Description of the satellite images used in study ....................................... 16 Table 2. Details of Landsat 5 TM Satellite Images .................................................. 20 Table 3. Details of Landsat 8 OLI/TIRS Satellite Images ......................................... 21 Table 4. Land Cover Classification scheme ............................................................ 24 Table 5. Thermal Constants of Landsat 5 TM and Landsat 8 OLI/TIRS .................. 27 Table 6. Accuracy Assessment of Land Cover between 1998,2008 and 2017 ......... 32 Table 7. Percent and Area of Land Cover Change Detection during the period from 1998-2017 ................................................................................................................... 34 Table 8. The absorb temperature of HCMC from 1998-2017 ................................... 44 Table 9. The land cover changes on land surface temperature from 1998-2017....... 46 Table 10. LST validation by the meteorological temperature data ........................... 48 viii ABBREVIATION ERDAS Earth Resources Data Analysis System GIS Geographic Information System HCMC Ho Chi Minh City LCC Land Cover Change LST Land Surface Temperature LULC Land Cover Land Use NDVI Normalized Difference Vegetation Index NDBI Normalized Difference Built Index OLI Operational Land Imager TM Thematic Mapper USGS United State Geological Survey ix PART I. INTRODUCTION 1.1 . Research rationale Urbanization is the physical growth of rural or natural land into urban areas as a results of population immigration to an existing urban area (Jahan,2012).Urbanization is also defined by the United Nations as movement of people from rural to urban areas with population growth equating to urban migration. According to Tran Thi Van el al.,2010 stated that urbanization is a main type of land use and land cover change in human history. Rapid urbanization and industrialization have resulted in sharp land cover change. Urban change not only impacts on land cover but also on urban climate (Tran T.Van, 2010) .The growing density of population and changing economic activities are determining factors of urban land use change (P.Prabu, Mithas Ahmad Dar, 2018). The population growth and socio-economic development result rapid transportation increasing, urban expansion reached to suburban areas. The increase in the world’s population recently has maximized the effects of the economic and agricultural activities. The United Nations projected that half of the world's population would live in urban areas at the end of 2008 (UN,2008). It is predicted that by 2050 about 64% of the developing world and 86% of the developed world will be urbanized (https://www.unfpa.org/urbanization). That is equivalent to approximately 3 billion urbanites by 2050, much of which will occur in Africa and Asia. Notably, the United Nations has also recently projected that nearly all global population growth from 2017 to 2030 will be absorbed by cities, about 1.1 billion new urbanites over the next 13 years (Barney Cohen et al.,2015). Urban areas are known to be the unhealthy areas or places for people to live. 1 A large amount of forest and agricultural land has been converted into housing, infrastructure and industrial estates. Thus, it has a great impact on environment and climate. Urban areas tend to experience a relatively higher temperature compared with the surrounding rural areas (S.Rajendran, 2009). There are two main causes engaging in urbanization : forcing people from rural areas to urban areas and drawing people into city. Meanwhile, in Vietnam , people are experiencing an unusual warm weather which is getting worse especially in urban areas like Ha Noi and Ho Chi Minh City is one of the most urbanized areas in Vietnam. In addition, Ho Chi Minh City (HCMC) is placed in the crossroad of several regions; the South-East, the South of Central Highland , the South of central coasts and the Mekong delta. These regions possess a great variety of resources , agricultural , aquatic and oil resources of which they are dominant (V.Thanh, 2005). HCMC situation is advantageous, in the middle of a vast rural zone constituted of a rice storage and a vast industrial plantation. With an important harbor system, HCM became the most important economical pole of the country. HCMC is also considered as the Central Business District of the country for its commercial areas are known in its role as the financial and business center of Vietnam.The continuous population growth economic development,with an increase in vehicular trips, cause a big problem in the city making it inconvenient for the people as the temperature in urban areas gets warmer from environmental changes. Therefore, HCMC is selected as the study area for it is one of the biggest and busiest cities in Vietnam. The continuous development of the city can highly affect the temperature particularly in summer time. In order to evaluate and monitor the temperature as well as the impact of urbanization according to the land cover changes 2 detection results on land surface temperature of HCMC during a 20-year period from 1998 to 2017 . Landsat imageries will be used by the help of remote sensing and GIS technology , which were well-developed and highly applied to different fields such as atmosphere, geology, hydrology...etc can be an effective way in knowing the relationship between Land Cover Change and Land Surface Temperature of HCMC. 1.2.Investigate the study area Ho Chi Minh City, also known as Saigon, is one of the urbaniest and most prosperous cities in Vietnam which is located in the South with the geography between 10º 46'10" N longitude and 106º 40'55" E latitudes (HCM statistical source) It is enclosed by Tay Ninh and Binh Duong provinces in the north, Dong Nai and Ba Ria - Vung Tau provinces in the east and Long An Province in the west(Figure 1) The total land area is 2095.01 km² and the city has 19 urban districts which aredesignated urban or suburban and 5 rural districts. The city has a tropical climate, specifically a tropical wet and dry climate, with an average humidity of 78–82% .The weather is divided into two distinctive seasons. The rainy season, with an average rainfall of about 1,979 millimeters annually (about 159 rainy days per year), usually begins in May and ends in late October. The dry season starts from December to April.The mean temperature is 28°C(82°F), with little variation throughout the year.The highest temperature recorded was 40.0 °C (104°F) in April while the lowest temperature recorded was 13.8°C (57°F) in January. On average, the city experiences between 2,400 to 2,700 hours of sunshine per year (H.Storch et al.,2011) 3 According to statistical data the population density has increased from 552 pers/km² in 1985 to 3,067 pers/km² in 2006 in urban areas about 10,905 pers/km and rural areas about 648 pers/km² (N.D.Hoa, 2014). The population growth causes the spatial expansion being through encroachment into adjacent agricultural and rural regions, especially in the northern part of the city due to the advantages of landscape and relative high topography. Hence, the study area is limited to this part. In this study, the central business district is investigated to become the main study area which is the place where the urbanization process is happening strongly in recent years. Figure 1. The Map of Study area Source: Google Earth Pro 1.3. Statement of Problem Before 1990, the line of immigrants flocking to Ho Chi Minh City to earn a job and earn a better living in Ho Chi Minh City was increasingly year by year. HCMC 4 is considered as the country’s central business district. The development of urban economy ,particularly , the private sector and foreign investments provoked a demand for the environment protection in the city which is in a process of fast urbanization. Hence, HCMC is home for the most important business centers and the main destination for people seeking job opportunities. That is an evident for increasing in population leading to establishments of more buildings, skyscrapers and houses which eventually deteriorates the urban environment such as air pollution. It can affect the people dwelling on or near the area and the natural environment as well. With this , the study will be conducted to answer these question: 1. How obvious is the urbanization of HCMC affecting to the Land Cover Change detection results from 1998 to 2017? 2. What is the impact of Land Cover Change on Land Surface Temperature in HCMC between 1998 and 2017? 3. How the real situation of Land Cover Change of HCMC can be found in this research? 1.4. Objectives of the Study The general aim of this study is to evaluate the impact of Land Cover Change on Land Surface Temperature in HCMC based on Landsat Imageries during a 20-year period from 1998 to 2017 . The specific objectives are: - To evaluate the land cover change of Ho Chi Minh City during 1998-2017 - To estimate the impact of Land Cover Changes on Land Surface Temperature between 1998 and 2017. - To identify the real situation of Land Cover Change in HCMC from 1998 to 2017. 1.5. Significance of Study 5 This study could provide additional information on the impact of Land Cover Change on Land Surface Temperature in HCMC. Specially, 1) how the land cover change detection affected to land use in HCMC; 2) the rate of change in each category based on Landsat imageries; 3) how the temperature varied in different type of land cover. The findings of this research may contribute to the future planning and referencing of HCMC which can also help the authorities , residents and urban planner. 1.6 . Limitation of the Study Although the study has reached its aim, there are still some limitations for this future investigation: (1) this study only focused on the land cover types but not on the building types (composition, construction, height etc. of the building); (2) the study did not able to get Landsat imageries with the same months owing to the limitation in the available data of the study area (HCMC), the new generation of open data satellite imagery may address this issue. 6 PART II. LITERATURE REVIEW 2.1. Land use/cover change Land cover change is defined as the change in physical characteristics of land surfaces such as forests, concrete , and water areas. Land cover refers to the physical characteristics of earth’s surface ,captured in the distribution of vegetation ,water,soil and other physical features of the land , including those created solely by human activities while land use refers to the way in which land has been used by humans and their habitat, usually with accent on the functional role of land for economic activities (Bujang et al.,2012). Land use affects land cover and changes in land cover affect land use (J.S Rawat,Manish Kumar, 2015). This land cover change can be determined by aerial and satellite imagery in seeing the changes over time by using remote sensing and GIS technology. With the information acquired from land cover maps for several different years , researchers can evaluate and detect the causes and effects of the development of an area. These maps can assess several environmental concerns. Moreover, theses land cover changes connect the socio-economic changes such as the population increase( National Ocean Service NOAA website). With this, many study use Land Cover Change detection in monitoring and evaluating the urbanization of an area on how the area changes from the past to the previous years. On the other hand, the effect of urbanization on land cover change in an area is also conducted by many researchers.Naturally the Earth surface is covered by different land cover types which are mainly distributed based on the environmental and climatical patterns (S.Youneszadeh,N.Amiri, P.Pilesjo, 2015). Urbanization leads to urban spatial expansion due to the demand for development and housing growth, as well as facilities areas to serve human life (Van, 2008). The growth of urban areas has 7 a significant impact on land cover by replacing areas of vegetation with residential and commercial areas and their related infrastructure, this escalates the land surface temperature (Ibrahim, 2017). Land use/cover change is a dynamic process taking place on the bio-physical surfaces that have take place over a period of time and space is of enormous importance in natural resource studies. Land use/cover change dynamics are important elements for earth resources. Land use/cover changes ares the major issues and challenges for the eco-friendly and sustainable development for the economic growth of any area. With the population explosion,human activities such as deforestation,soil erosion, global warming and pollution are very harmful for the environment (J.S Rawat, Vivekanand Biswas, Manish Kumar, 2013). There are several more studies related to urbanization and land cover changes which were conducted and most of them aimed to know the influence of urbanization on the alternation of land cover type. 2.2. Land Surface Temperature (LST) Land surface temperature is how hot the “surface” of the Earth would feel to the touch in a particular location. From a satellite’s point of view , the “surface” is whatever it sees when it looks through the atmosphere to the ground. It could be snow and ice, the grass on a lawn , the roof of a building or the leaves in the canopy of a forest (NASA Earth Observatory website).LST is one of the key parameters for estimating surface energy budget assessing land cover changes and other characteristics of the Earth’s surface (Ssrivastava et al,.2010).Measuring and analyzing of surface temperature and surface emissivity by using remote sensing data and GIS analysis is virtually used by various scholars over the world (Mehebub Sahana, Raihan Ahmed, Haroon Sajjad, 2016). 8 Environmental and urban climate studies use land surface temperature and emissivity data for numerous purposes but mainly to analyze LST patterns and how they are connected to surface characteristics,urban heat island forecasts (Ibrahim, 2017).Urban temperature rise and formation of urban heat island (UHI) has been a concern for more than 60 years (Swades Pal, Sk.Ziaul, 2017).Land surface processes such as changes in the green vegetation fraction are keys for the distribution of UHI and are detectable from satellites (Yonghong Hu and Gensuo Jia, 2009). Besides, Land Surface Temperature derived from remote sensing data is unique source of information in oder to define surface urban heat islands and it has been widely used as indicator for UHI research.With the introduction of thermal remote sensing ,LST information is available from a series of satellite sensors such as Landsat, MODIS, and ASTER that cover a wide range of the earth surface (Duy X.Tran et al., 2016). In addition ,LST derived from remote sensing imageries might be better to show the hottest and coolest areas as compared to temperature collected from urban weather station(Nichol To,2012). The combination of the land use analysis result with the mean land surface temperature can offer useful information to study the land cover change effects in Ho Chi Minh City. 2.3 Impact of Land Cover Change on Land Surface Temperature Xiaolu Shou and Yi-Chen Wang (2010) have studied about Dynamics of Land Surface Temperature in response to Land use/cover change stated that rapid population growth and continuous exploitation of natural resources during the past century have caused land use/cover change worldwide. This study aimed to investigate the impact of land cover/use change on Land Surface Temperature in a rapidly urbanisation city, Kunming in south-west China. Using Thermatic Mapper (TM) imageries of 1992 and 9 2006 were derived from USGS website to examine how LST responded to urban growth. The results showed that rapid urbanization in Kunming altered the local thermal environment,particularly in increseing the LST in the zone surrounding urban core.On the other hand, a group of scholars including S.Youneszadeh, N.Amiri,P.Pilesjo (2015) conducted a research called “ The effect of Land use change on Land Surface Temperature in Netherlands” indicated that the inland water and offshore areas has the highest night land surface temperature in the years of 2003,2006 and 2008 surveyed. Addition to that, in the study of Ashraf M.Dewan, Rober J.Corner in Curtin University, Western Australia concluded that the differences between the mean surface temperature and land cover type in the capital of Bangladesh,Dhaka are highly significant. The urban built up area has increased by 67% since 1990. Moreover, Clause Rinner and Mushtag Hussain (2011) from Department of Geography , Ryerson Univerisity, Toronto,Canada found out that the average temperatures are substantially higher for commercial resources and industrial land uses while lower temperature for park and recreational land uses as well as water. These findings explained how the urban expansion and change in land use/cover can affect the temperature in the urban areas. With this outcomes, urban planners and other environmental concerning citizens could make numerous decisions on urban planning and how to lessen the continuous increase in temperature. However, studies noticed an increase in urban growth wih a related decrease in vegetation , which resulted in an alteration of urban microclimate. Another study determined the land surface temperature and vegetation abundance relationship. Different indices of vegetation indicate an abundance of vegetation ,such as Green Fractional Vegetation(GVF) and Normalized Difference Vegetation Index (NDVI) 10 A negetaive connection between the NDVI and Land Surface Temperature was revealed ,as well as the green area’s cooling effect due to soil moisture variations, land surface emissivity, albedo and profusion of vegetation resulting in the fall of variable temperatures of dense vegetation (Ibrahim, 2017). 2.4. Land Cover Change and Land Surface Temperature in Vietnam Research have done in Hanoi – Capital of Vietnam (Duy X.Tran et al.,,2016) that urbanization was faster in and around Hanoi inner city than in other surrounding areas by examining the relationship between LST and NDVI, NDBI within each LULC type. They discovered that the correlation is not always linear since it may vary between each LULC type as well as being subject to the geographic location and season. This study based on Getis Ord Gi* statistics method (Duy X.Tran et al.,2016) to analyze changes in LST patterns through time. The identification of hot spot or cold spot areas by such method does not depend on whether the mean temperature is high or low so the effect of different LST values throughout time is reduced. In general, more than 20% of the city area is always warmer whereas less than 10% of the city area is always colder than the mean zonal LST. Hot spots tend to increase through time (from 27.95% in 2003 to 34.61% in 2015) anstrongly correlate with urban expansion. In Vietnam, land use and land cover patterns have undergone a fundamental change due to rapid economic development under its reformative economic policies. Urban growth has been speeding up, as a result, an extreme stress to the environment has occured. This is particularly true in Ho Chi Minh City where agricultural land has been gradually disappearing each year, converted into urban or related uses. Furthermore, because of the lack of appropriate land use planning and the measures for sustainable 11