3. 1 Comprehensive study on land surface process and pattern
The surface system includes the structure, evolution, development and interaction of environment, resources and social economy closely related to human beings in time and space. It is the most complicated, important and most influenced by human activities. Therefore, the study of it is an important field in the future development of geographical science. At present, people pay more and more attention to the surface environment closely related to human survival and its changing trend. In essence, the change of land surface environment is the result of the change of surface process mode and intensity in a specific area under the action of human or natural factors. The study of land surface process will develop in two directions: micro-deepening and macro-synthesis. The key lies in the comprehensive study of interface process in geographical system. Its main significance lies in that it can effectively study the exchange of matter, energy and information between open systems, thus promoting the deepening of geography to the theoretical level; The study of interface process is actually the study of interface between systems, which will promote the development of comprehensive methods of geography, lead to the infiltration of interdisciplinary and cross-sectoral and the introduction of achievements of adjacent disciplines.
Land surface system has the characteristics of uneven distribution in time and space, and the level of understanding of global problems depends to a great extent on the understanding and research depth of its regional differentiation. Dividing land into different geographical types, studying the process, structure and evolution of different geographical types and comparing their similarities and differences are important contents of land surface pattern research. In the process of studying the land surface, we should also pay attention to the land-sea interaction, especially the influence and function of the ocean on the land process. From the situation of global environmental change, earth system science and global economic integration, we also need a better, easy-to-use regional framework that takes into account nature and humanity, and updates it in time according to objective and actual changes. China has a vast territory, bordering the Pacific Ocean in the east and the hinterland of Eurasia in the west. North and South straddle the tropics, subtropics and temperate zones. There are many mountain plateaus, and the monsoon climate is remarkable. There are both wet forests and extremely dry deserts, forming a unique pattern of three natural regions juxtaposed. The complex and diverse natural environment provides a broad stage for the comparative study of different regions, types and natural processes. A comprehensive study of the relationship between land surface processes and patterns will promote the study of regional response to global environmental change and become the basic theory for the scientific development of land surface systems.
The main research directions in the near future include: hydrological cycle process, water conversion mechanism and its physical experiment simulation; Material migration process of river basin system and its influence on regional environment: the development process of slope erosion and the improvement and utilization of slope; Land evolution process and its regulation mechanism; Soil-plant-atmosphere continuum process and regional scale transformation: environmental biogeochemical processes of life elements, pollutants, heavy metals and rare earth elements and their health effects; Comprehensive study of natural regional system; Environmental evolution process in typical areas, etc.
3.2 Global environmental change and its regional response
Because the increase in the concentration of greenhouse gases such as carbon dioxide in the atmosphere may lead to global warming, it has attracted close attention from the public and governments all over the world. In response to global environmental changes such as climate change, ozone layer destruction, biodiversity protection and desertification, relevant international conventions have been formulated and cooperation has been carried out to promote the sustainable development of human society. The earth and the surface of the earth are naturally an organic whole, and there is close interaction between the circles in the world. With the population growth, social development and scientific and technological progress, the influence of human activities on the geographical environment is becoming more and more intense. The influence exerted by human beings in one field will have an effect on other fields, and today's measures will have an impact on the future. Today's global environmental changes are closely related to the slow accumulation of long-term human activities.
The study of global environmental change is an important research field of geography in the past, present and future. Under the impetus of international geosphere-biosphere program (IGBP) and International Human Factors Program for Global Change (IHDP), we are constantly exploring new research fields. Global environmental change and its regional response involve many fields, such as paleogeographic environment evolution, land use and land cover change, natural disaster reduction, typical regional environmental positioning research and global environmental change countermeasures. The Qinghai-Tibet Plateau and the Loess Plateau in China are closely related to global environmental changes, and they are areas where geography can display its special skills and talents.
Based on China's national conditions and geographical characteristics, the main research directions at present include: the evolution of Holocene paleogeographic environment, especially the changes of climatic environment in the historical period of nearly 2000 years; A comprehensive study of polar regions, mountains and cryosphere; Land use and land cover change and their driving forces; Global environmental change and its influence and response to environmentally fragile areas; Study on strategic countermeasures of global environmental change. Among them, the socio-economic countermeasures of global environmental change involve the change of natural zone, the structure and layout of land use, agriculture, forestry and animal husbandry, the adjustment of energy structure, the defensive measures of coastal zone, the rational utilization of natural resources and the prevention and control of natural disasters.
3.3. Natural resource protection and ecological environment construction
Water resources, land resources and biological resources are important components of the earth's human home support system. China's per capita natural resources are small and unevenly distributed in space. The rapid economic development has increased the pressure on natural resources. Long-term predatory development and unreasonable management have led to a series of problems such as exhaustion of natural resources, environmental deterioration and loss of biodiversity, which have become a serious obstacle to the sustainable development of China's social economy. Sustainable development requires the establishment of a harmonious and coordinated relationship between social and economic development and population, resources and environment in different scales.
Therefore, it is necessary to comprehensively study the pattern, process and dynamics of various natural resources in China, study the relationship between various natural resources from the perspective of integrity, and reveal their combination characteristics and evolution laws. This paper studies the relationship between natural resources and ecological environment, the relationship between resources and environment in different regions, especially the relationship between human activities and resources and environment, reveals the temporal and spatial change law of natural resources and evaluates the environmental effect of natural resources development and utilization, expounds the influence of human commercial activities on natural resources and ecological environment, and puts forward its regulation mechanism and countermeasures. There are obvious regional differences between land degradation and ecological environment deterioration, so it is necessary to divide different regional types, conduct a comprehensive and systematic study on their genetic mechanism, dynamic process and development trend, and put forward the overall deployment and ways of macro-control strategy and ecological environment construction.
The main research directions in the field of resources and environment are: the evolution law of water cycle, the theoretical methods of dynamic evaluation of water resources and water environment, the ways of efficient utilization of water resources and the decision of optimal allocation; Evolution mechanism of land quality and its sustainable utilization, coupling mechanism of water and soil resources and its regulation; Environmental quality assessment, prediction and zoning; Eco-environmental public welfare function and asset value evaluation, dynamic monitoring and trend prediction of eco-environmental positioning in typical regions; Eco-geographical division and study on environmentally fragile areas; Eco-environmental evolution mechanism and regulation in key areas (such as Yellow River Basin, Northwest Arid Area and Southeast Coastal Rapid Development Area).
3.4. Mechanism and regulation of regional sustainable development and man-land system
There are obvious regional differences in the surface of the earth. Different regions have different connotations of population, resources, environment and development. The study of regional sustainable development is an area where geography can give full play to its advantages. Regional economic growth and stable social development should be based on effective control of population growth, rational utilization of natural resources and gradual improvement of environmental quality, promote the coordination and balance of different types of regions, and narrow the gap in regional development level. The study of regional sustainable development needs to take population, resources, environment and development as a whole, study their structure, function and interaction mechanism, predict their development trend, formulate control and management countermeasures, and put forward optimization models of different types of regional sustainable development.
Man-land system is the abbreviation of regional system of man-land relationship, and it is a complex system composed of natural, economic and social subsystems. The regional system of man-land relationship is a dynamic structure formed by the interaction between "man" (human and its economic and social activities) and "land" (natural environment) on the earth surface in a specific region. Man-land system includes man's dependence on land and man's initiative, which changes with the development of human society. Historical experience shows that the relationship between man and land should be harmonious, and human beings should consciously use and transform land (natural environment) according to objective laws, and properly handle the relationship between them, so as to achieve the goal of sustainable development. The study of man-land system is interdisciplinary, and its central goal is to coordinate the relationship between man and land, focusing on the optimization of man-land system and implementing it in regional sustainable development. In the coordination of human-land relationship, there are direct and indirect feedback effects between population and economic and social development, natural resources and environment, which are intertwined. Natural resources and natural environment can promote and control human activities; Humans invest controllable resources in natural systems, control natural disasters, improve environmental quality and develop various resources, so as to realize output and optimize it. Any regional development, regional planning and regional management must aim at improving the structure of regional human-land interaction, developing the potential of human-land interaction and accelerating the virtuous circle of human-land interaction in the regional system. At present, more emphasis is placed on the practicality, foresight and guidance of research results [14].
At present, the main research directions in this field include: the index system of regional sustainable development; Spatial differentiation law of socio-economic factors and its structural optimization; Research on human settlement environment and urbanization; The influence of human factors on the natural environment and its regulation: the mechanism of regional sustainable development and the optimal regulation of regional system structure; the dynamic mechanism of man-land system, including the structure, function, openness and stability of man-land system; Analysis of the types of man-land system and its regional differentiation: dynamic simulation and system regulation of the succession process of man-land system.
3.5. Research on Geo-information Science and "Digital Earth" Strategy
Geo-information science is the product of the cross-integration of earth system science, space technology and information science. It uses information flow as a means to study the motion state and mode of material flow, energy flow and people flow in the earth system. Because of the multidisciplinary nature of geo-information science, it can provide strong support for the comprehensive integration of many research fields in the earth system and the research and solution of large-scale geoscience problems, and even provide brand-new research and solutions. The formation and development of geographic information science, as the research direction of geographic science in the information age, has a wide range of social needs [4, 12, 13].
With the development of earth observation and information technology, human beings have the ability to systematically study global problems and promote the modernization and informatization of scientific research on the earth system. The core idea of "Digital Earth" is to study and solve global problems as a whole, and make maximum use of information resources through digital means. It not only provides a platform for earth visualization, but also provides a basic model framework for earth science experiments. Using this framework, we can repeat the evolution and interaction history of the whole earth, evaluate the present situation and predict the future. The research of geo-information science has laid a scientific foundation for solving the key technology of "Digital Earth", and its development will help to promote the research of "Digital Earth Strategy and China Countermeasures".
At present, the main research directions of geo-information science include: ① the cognition of spatio-temporal information, the expression, interpretation and inversion of spatio-temporal information, the research of geographic data model and information mechanism; ② Multi-source data fusion, construction and update of large geoscience database; ③ Spatial-temporal analysis and model research of geo-information such as geo-knowledge discovery, geo-information atlas, map language and cognition, geo-information model; (4) Geoscience data acquisition and processing and virtual simulation infrastructure; (5) information * * * construction * * enjoy norms, standards and legislation.
4 Countermeasures and suggestions
The five frontier areas of geography are closely related and mutually supportive. We should give full play to the comprehensive advantages of geography and integrate physical geography, human geography and geographic information science and technology.
4. 1 Strengthen basic work, improve and build research support system.
Some regions with global significance in China have distinctive features, which are the windows and bridges between geography and the international community. Strengthen forward-looking basic research, link the past with the future, and encourage original innovation. From the perspective of source innovation, while making full use of satellite data and information systems, we should pay special attention to and strengthen the basic work of collecting and analyzing first-hand scientific data such as field investigation and positioning test observation. Therefore, it is necessary to further build and improve the research support systems such as field positioning observation bases, precision analysis and testing, and experimental simulation in different types of regions to ensure the realization of spatio-temporal dynamic analysis and simulation, thus improving the informationization and modernization level of geography itself.
4.2 Organize the intersection and integration of natural field and humanities field
Geography has both the nature of natural science and social science, but at present, it mostly stays in the bilateral combination between disciplines, and there is still a long way to go to realize the intersection of natural and humanities fields. It is necessary to organize the implementation of comprehensive research plans, establish interdisciplinary research organizations, promote mutual penetration and multidisciplinary integration, and strive to achieve comprehensive integration. Strengthen the construction of information network, promote the comprehensive utilization of satellite data, positioning observation and socio-economic statistics, and improve the modernization level of strategic analysis and engineering consultation.
4.3. Pay attention to the popularization of geographical science knowledge and adult education.
Global environmental change and regional sustainable development are important issues of concern to human society today, and geographical scientific knowledge, resources and environmental issues are related to people's quality of life and national ecological security, which not only professionals need to master, but also management decision makers and the public want to know. Through various educational and popular science media and channels, strengthen the publication of geographical periodicals, promote the preparation of geographical museums, develop networks and distance education, widely disseminate geographical scientific knowledge, and urge the whole society to know the earth, respect nature, strengthen environmental protection awareness, save resources, establish the concept of sustainable development, and build a beautiful home for mankind. So as to open up new application fields of geography, expand the social demand of geography and promote the understanding and understanding of geography in society.