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MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY OF SCIENCE AND TECHNOLOGY ----------------------------- NGUYEN THI THUY STUDY ON GEOGRAPHIC BASIS IN EXPLOITING AND USING LAND FOR SUSTAINABLE PLANNING IN DA LAT CITY AND ITS VICINITIES - LAM DONG PROVINCE Major: Geography of Resource and Environment Code: 9 44 02 20 THESIS SUMMARY FOR GEOGRAPHY DOCTOR Hà Nội - 2019 The thesis was completed in: Graduate University of Science and TechnologyVietnam Academy of Science and Technology Science instructor 1: Ph.D. Nguyen Dinh Ky Science instructor 2: Prof. Ph.D. Sc. Hoang Van Huay Reviewer 1: ……………………………………………… Reviewer 2: ……………………………………………… Reviewer 3: ……………………………………………… The thesis will be defended in front of the Institute's doctoral thesis evaluation council, meeting at the Graduate University of Science and Technology - Vietnam Academy of Science and Technology at …… hour ……, date …… month …… year 201 …… Thesis can be found in: - The Library of Graduate University of Science and Technology - Vietnam’s National Library INTRODUCTION 1. The necessity of the thesis Urbanization is an inevitable trend in the history of social development. Urban population has now reached 50% of the total world’s population, with rapid urbanization, especially in developing countries. Urban concentration has brought greater economic scales to cities and territories, but its downside can lead to negative impacts on resource degradation and environmental pollution. To address these challenges, various approaches in urban and territorial planning have been studied and implemented. Located on Lang Biang Plateau, with an average altitude of 1,500m above sea level, Da Lat City is the first-class city of Lam Dong province. This is a famous vacation and tourism place of Vietnam. However, over 120 years of formation and development, today's landscape of Da Lat has had a great change. The city's space has been constantly expanding in terms of residential land and agricultural production land, narrowing forest land, increasing the density of housing and agricultural production works, concentrating in the central area, which have changed the landscape structure and polluted the city. It can be seen that the changes in the land use exploitation structure are the direct reasons that cause Da Lat to be in danger of losing the "proportion of space" in the landscape structure and the decline of the entire ecosystem. In order to overcome the problems and develop Da Lat City sustainably, an optimal solution is directed, that is to promote the potential of vicinities with similar climate - soil conditions. On that basis, the government approved the "General Plan of Da Lat City and its vicinities until 2030 and vision to 2050" (May 2014). According to the plan, Da Lat city will become a major city, the boundary will be expanded to vicinities and cover an area of 8.5 times as much as today. The urgent problem is that there is a need for comprehensive studies and assessments of the natural potential, situation and demand of land use, thereby establishing a sustainable land use planning and solution to expand the land use spaces of Da Lat City, resolving the conflicts in exploitation and land use between spaces, and meeting the development orientation of the city in the future. Researching on integrated natural geography is a comprehensive and spatially specific approach, a comprehensive research of natural and socioeconomic components in the complex interplay and interaction in a specific territory. Since then, the direction and solution of resource use and socioeconomic development have been set in accordance with the geographical laws of the territory. This is an effective research method for the planning of rational use of resources and nature protection in the direction of sustainable development for any territory. Stemming from the urgent requirements of Da Lat city, with the desire to contribute to the city's sustainable development, the thesis: "Study on geographic basis in exploiting and using land for sustainable planning of Da Lat city and its vicinities - Lam Dong province" has been selected to perform. 1 2. Research objectives Establishment of scientific grounds for sustainable planning and land use of Da Lat city and its vicinities on the basis of research, exploitation and use of land based on geographic approach. 3. Research implementions - Overview of related documents, as a basis for building a theoretical basis and methods, research process of land use exploitation based on geographic approach for sustainable planning and land use of Da Lat City and its vicinities; - Analyzing characteristics of arising conditions – degeneration of soil and land resources in Da Lat city and its vicinities; - Identifying causes, process of soil degradation and evaluation of aggregated soil degradation in Da Lat city and its vicinities; - Assessing and classify land in Da Lat city and its vicinities for the main land use types; - Determining the percentile and norm system, and making a geographic zoning map of the soil of Da Lat city and its vicinities; - Proposing spatial orientation and solutions for sustainable land use planning in Da Lat city and its vicinities. 4. Research area and objects - Research area: Da Lat city and its vicinities (including Lac Duong, Don Duong, Duc Trong and Lam Ha districts). - Research objects: Arising geographical factors - degradation and land resources. 5. Protected thesic points - Point 1: The diverse and complex differentiation of the soil cover reflects the specific geographic laws and the corresponding processes of land generation, development and degradation in the territory of Da Lat city and its vicinities, expressed through a system of land units and geographic zoning units with diverse characteristics and potentials. - Point 2: Integrating results of research on characteristics and directions of land use and protection of each soil sub-region with results of land classification and soil degradation assessment, creating a reliable scientific basis for the proposal of spatial orientation and solutions for sustainable land use planning of Da Lat city and its vicinities. 6. New thesic points of - Clarifying the regular characteristics and spatial division of soil cover of Da Lat city and its vicinities, as evidenced by the system of soil geographic zoning units shown on the map at 1: 100,000 scale. - Proposing spatial orientation and solutions for sustainable land use of Da Lat city and its vicinities, based on an integrated analysis of the results of assessment of land classification, integrated soil degradation assessment and soil geographic zoning. 2 7. Scientific and practical contributions - Scientific contributions: Contribute to supplementing the theoretical basis and research methods of land use exploitation based on geographic approach for sustainable planning and land use of tropical highland urban areas. Enrich the research direction of applied geography in rational planning and protection of natural resources for sustainable development of the territory. - Practical contributions: The research results are a scientific basis for the locality to refer to territorial organizations, planning and land use planning in the orientation of sustainable development. 8. The structure of the thesis In addition to the introduction, conclusions and recommendations, references and appendices, the thesis content consists of 4 chapters: Chapter 1. Theoretical basis and research methods of land use exploitation with geographic approach for sustainable planning and land use Chapter 2. Characteristics of arising geographical conditions degeneration of soil and land resources in Da Lat city and its vicinities; Chapter 3. Evaluation, classification of land and general land degradation in da lat city and its vicinities; Chapter 4 Proposal of spatial orientation and sustainable land use solutions for Da Lat city and its vicinities. Chapter 1. THEORETICAL BASIS AND RESEARCH METHODS OF LAND USE EXPLOITATION WITH GEOGRAPHIC APPROACH FOR SUSTAINABLE PLANNING AND LAND USE 1.1. Some used concepts 1.1.1. Soil, land, land resources and environment 1.1.1.1. Soil From a biological perspective, V.V. Docuchaev (1879) gave the definition: “Soil is a natural entity with its own developmental origin and history, an entity with complex and diverse processes taking place in it, formed under the mutual influence of basement rocks, topography, climate, organisms, humans and time”. Fertility is a basic property of the soil, defined: “Fertility is the ability of the soil to provide plants with water, mineral nutrients and other necessary elements (air, temperature, etc) for plants to grow and develop”. 1.1.1.2. Land According to FAO (1976), Land covers all elements of the natural environment, which affect land use potential, including climate, topography, soil, hydrology, organisms, and results of human activity in the past and present. So land is a broader concept than soil. 1.1.1.3. Land resources and environment Land resources: It is understood as the entire crust of the earth in which organisms and humans can live Land environment: Is a complex ecosystem, formed through physical, chemical and biological processes. 3 1.1.2. Land evaluation and soil degradation 1.1.2.1. Land evaluation Land evaluation is defined as:“Assess the effectiveness of land when used for a specific purpose, involving the conduct of studies on soil, climate, vegetation and other aspects of land to identify and compare the requirements of specific types of land use and land conditions for the purpose of the evaluation” (FAO, 1976, 2007). 1.1.2.2. Soil degradation As defined by FAO (2002): “Soil degradation is a temporary or permanent decrease in the productive capacity of soil". From the perspective of synthetic natural geography, Nguyen Dinh Ky (1987, 1990) stated that: “In the stage of generation, development, soil degradation is governed by inherent natural processes called potential degradation. Degeneration of each element of soil properties or comprehensive degradation in each time of land use exploitation is considered as current degradation”. 1.1.3. Sustainable land use and land use planning, space organization 1.1.3.1. Sustainable land use Sustainable land use is a form of land use that helps maintain the soil's natural fertility and allows efficient production and regeneration of natural resources on a long-term basis. FAO (1993) developed the definition of specific sustainability in agriculture: "Sustainable agricultural land use is a type of land use that can produce enough to meet the needs of current and future residents while preserving and improving land resources to ensure production." 1.1.3.2. Land use planning FAO/UNEP (1999) gave the definition: "Land use planning is a systematic evaluation of land and water potentials, land use plans and socio-economic conditions to select and apply the best land use plans." In other words, land use planning is the key to a sustainable development of a territory. 1.1.3.3. Space Organization The concept of spatial organization or territorial organization is agreed to be: The arrangement and coordination of objects in multidisciplinary relationships in a specific area in order to rationally use natural, labor potentials, socio-economic geographic location and technical facilities have been and will be built to bring about high socio-economic benefits and improve the living standards of the people in that region. Spatial/ territorial organizations devise integrated and regional development strategies for each region to achieve the territorial sustainable development goals. 1.2. Overview of research works on land evaluation, land classification and soil degradation 1.2.1. The research works on land evaluation and classification 4 1.2.1.1. In the world Irrigated land classification (1951) and potential-based land classification (1961) are two evaluation systems built specifically for the condition of the United States based on the constraints of land that interfere with land use; Evaluate and classify land according to V.V. Docuchaev's point of view in Russia and Eastern Europe (1960) by scoring derived factors and soil properties on the basis of an agreed benchmark scale. In order to unify worldwide land evaluation standards, FAO (1976) developed "Land evaluation framework". Actually, this is a set of principles and methods, on which the land evaluation systems of any country and at any rate can be built. FAO also provided specific guidance on the detailed application of the "evaluation framework" for specific subjects such as: Land evaluation for rain-fed agriculture (1983), Land evaluation for forestry (1984), Land evaluation for irrigated agriculture (1985), Land evaluation for extensive pastures (1991). At the same time, along with the development of technology and its application in the land evaluation process has contributed to quantification and correction of research results. Studies on land evaluation based on FAO's guiding framework and GIS application have become popular in the world, mainly in the following directions: GIS application and available utilities of GIS; GIS integration and advanced tools (RS, GPS, etc); GIS integration and automated soil evaluation software (ALES). In addition, FAO has also provided specific guidelines on the land evaluation process in land use planning for sustainable development, such as: land evaluation for development (1986), guidelines for land use planning (1993), land evaluation framework for sustainable land management (FESLM, 1993), planning for sustainable use of land resources (1995) and two latest guidelines on integrated planning for sustainable management of land resources (1999) and land evaluation towards a revised framework (2007). These guidelines have suggested considering factors related to sustainability (natural suitability, high economic efficiency, social acceptance and no negative impact on the environment) in the land evaluation process, using the multi-criteria decision analysis (MCDA). 1.2.1.2. In Vietnam Since the late 1980s, FAO land evaluation studies have been conducted extensively in localities across the country. Land evaluation becomes a mandatory rule in land use planning. The works are carried out from large ecological regions to provinces, districts and specific research areas, for example: at regional level, there are studies of Vu Cao Thai (1988), Tran An Phong (1992), Nguyen Van Toan (2005), Vu Nang Dung (2015), etc; At the detailed level, there are studies of Nguyen Khang (2001), Tran An Phong (2002, 2004), Luu The Anh (2003), etc. 5 At the same time, along with the technological development of the world, current studies on land evaluation in our country are applying GIS, in addition to combining with RS, GPS and automated soil evaluation software and multi-criteria decision analysis. Some typical works by: Tran An Phong (2001), Nhu Thi Xuan (2006), Le Canh Dinh (2011), Vu Nang Dung (2014), Nguyen Thanh Tuan (2015), etc. 1.2.2. The research works on soil degradation assessment 1.2.2.1. In the world Researching on soil degradation is gradually opened as a research direction in soil science for effective planning and sustainable land use. From 1987-1990, the project “Global Assessment of Human-induced Soil Degradation (GLASOD)” developed by UNEP and ISRIC to produce a map of global soil degradation status at 1: 10,000,000 scale. In addition to global-scale studies, soil degradation has also been studied in detail for regions, countries and territories, including the following typical works: Project on Assessment of Soil Degradation in South and Southeast Asia (ASSOD) (FAO and ISRIC, 1994-1997); Project on Assessment of Soil Degradation in Central and Eastern Europe (SOVEUR) (FAO and ISRIC, 1997-2000); Project on Assessment of Soil Degradation in dry areas (LADA) in 6 countries: Argentina, China, Cuba, Senegal, South Africa and Tunisia (FAO and GEF, 2002-2008); Assessment of Soil Degradation in Togo ( ORSTOM, 1991 - 1994); Soil degradation research in India (NBSS, 1992); Global Soil degradation Mapping (Gibbs HK, et al, 2015). 1.2.2.2. In Vietnam The studies of soil degradation in our country began in the late 1960s and gradually became a research branch of soil science, focusing on the following directions: Studies on soil degradation according to types of degradation: typical studies on soil degradation due to erosion by Nguyen Quang My (1980, 2005), Nguyen Trong Ha (1996), etc; Studies on land degradation according to types of degradation (with application of ASSOD system) of Vo Quang Minh (2003), Nguyen Xuan Thanh (2009), Center for Surveying and Assessing Land Resources - Ministry of Natural Resources and Environment (2009-2012). Studies on land degradation based on the aggregated natural geographic point of view of Nguyen Dinh Ky et al. (1987, 1990, 1998, 2007, 2012, 2015); Studies on land degradation, and rehabilitation and restoration measures of Nguyen Tu Siem and Thai Phien (1998, 1999, 2002); In addition, studies applying other methods of soil degradation assessment have been implemented, such as those of Nguyen Quang Viet (2014); Nguyen Thi Thuy (2016). 6 1.2.3. The research works in Da Lat city and its vicinities 1.2.3.1. Studies on land evaluation and classification From 1995 to 2010, the People's Committee of Lam Dong Province conducted the program "Evaluation of agricultural land in Lam Dong", conducted by the Southern Soils and Fertilizers Research Institute - SFRI. Based on FAO (1976) guidelines, assessment of agricultural land for communes at 1/10,000 scale maps, districts/cities at 1/25,000 scale to assess land quality, proposed land use and crop intensive measures. From 2009 to 2012, Center for Surveying and Assessing Land Resources Vietnam General Department of Land Administration conducted Land evaluation for agricultural production land in Lam Dong province at 1/100,000 scale. From 2011-2015, National Institute of Agricultural Planning and Projection conducted Land evaluation and proposing solutions for sustainable development of industrial crops and food crops in Lam Dong at 1/ 100,000 scale. In addition, there are detailed land evaluation studies in districts, such as those of Le Canh Dinh and Pham Quang Khanh, (2005); Vo Thi Phuong Thuy and Le Canh Dinh (2011); ect. 1.2.3.2. Studies on soil degradation In 1998, in a cooperation program between the Institute of Geography and the French National Research Institute for Sustainable Development (IRD), author Brabant P. established "Soil degradation map of Lam Dong at 1/100,000 scale" on the basis of interpreting satellite images from 1992 to 1998, combined with color aerial photographs and field survey results. In 2009-2012, the Center for Surveying and Assessing Land Resources Vietnam General Department of Land Administration conducted the assessment of soil degradation status in Lam Dong province at 1/100,000 scale on the basis of applying the ASSOD soil degradation assessment system. In 2011-2015, Luu The Anh, Nguyen Dinh Ky et al established potential soil degradation, current land degradation and aggregated land degradation maps of Lam Dong province at 1/100,000 scale from the perspective of aggregated natural geography. 1.3. Theory of research on land use exploitation according to geographic approach for sustainable land planning and land use 1.3.1. The nature of geographic approach in the study on rational use and protection of natural resources Geography is a complete scientific system, studying the natural world on the earth's surface, development conditions and production distribution characteristics and interaction between human society and geographic environment (Le Ba Thao, 1987). The objects of the study of geoscience are the geographic objects, also known as the geographic integers, in which the geographical crust is the geographic integer at planet scale. It is the interdependence and interaction between the geographic components that make up the internal differentiation of the geographical crust, forming geographic integers of different scales. 7 In order to have a basis for selecting the most appropriate territory for different uses, it is necessary to make an overall assessment of natural geographic integers according to ecological adaptation, economic efficiency, environmental and social sustainability. Thus, the geographic basis within the scope of the thesis can be understood simply as the results of the study towards the integrated assessment of natural geographic integers created for various purpose of use, as a basis for proposing orientations for rational use planning and protection of natural resources for sustainable development of a territory. 1.3.2. Researching on land use exploitation according to geographic approach for sustainable planning and land use Soil is a function of all other geographic factors, the most obvious expression of a geographic integer. Accordingly, the soil cover as a geographic structure has the structure from the simplest (soil unit) to the most complex (soil cover). In land evaluation, land units are interpreted as soil areas with relatively homogeneous (natural and socio-economic) attributes whereby the boundaries between it and the others can be distinguished. Thus, according to the geographic approach, the land units are also the geographic integers (incomplete) and are a structural unit of the soil cover. Accordingly, the integrated research and evaluation of land units to determine the direction of sustainable use and exploitation for specific purposes of the territory is the geographic approach in the study of land use for sustainable planning and land use. In other words, it is the study of the arrangement of land use types on land units in a sustainable manner, both in accordance with the arising geographical laws, the development of the soil cover, and promoting the maximum potential of natural land, bringing high economic efficiency and minimizing the negative impacts on land environment resources. Thus, the integration of land classification and soil degradation assessment results with soil geographic zoning will more effectively show the results of land aggregate assessment in the close relationship between soil geographic sub-regions. The purpose of this process is to give a direction to the land use space and develop sustainable territories, as a scientific basis in planning and land use of the territory in the direction of sustainable development. 1.3.2.1. Land Unit Map Land Unit Map is the basic maps in the evaluation that completely and objectively reflects the land properties in the relationship and the reciprocal impact with arising geographic factors - soil degradation. The Land Unit Mapping method is the overlap of many types of factor maps showing land properties such as: land map, topographic slope, isometric map of rain, temperature, watering ability, etc. The results of the construction of the land units are relatively uniform in all criteria, shown on the map as lands with enough characteristics to make a difference with the other land units. 8