Compulsory 2 Human Geography
Chapter 1 Population
I. Population Growth
1. The main factors affecting the population growth: the level of productivity, health care and education affects the mortality rate and birth rate of the population, which in turn influences the pattern of population growth. In addition, policies, social welfare, and natural disasters also affect population growth.
2. Patterns of population growth (patterns of population reproduction): High-low-high (developing countries with lower levels), three-low (developed countries), and transition from "high-low-high" to "three-low" (developing countries with higher levels).
3. World population growth: Africa has the highest rate of natural population growth, Europe the lowest; Asia has the largest net population increase.
4. Population Problems - Population growth is too fast: high population pressure - control population (China practicing family planning)
Population growth is too slow: aging population - -Encourage births, accept immigrants (China relies on the development of productive forces)
2. Population Migration
1. The main reasons for population migration: economic (backward areas to developed areas), political (political persecution, wars, and state-organized population migration), socio-cultural (religious persecution, ethnic discrimination), ecological environment, and other factors (family background and marriage, defection to friends and relatives, escape from discrimination).
2, the significance of population migration (effect)
(1) Benefits: ① Strengthening national unity and promoting ethnic integration ② Strengthening cultural exchanges ③ Reducing population pressure in the place of migration ④ Providing cheap labor for the place of migration.
(2) Disadvantages: ① cause outflow of talents from the place of relocation ② increase the difficulty of social management in the place of relocation
Three, population distribution and population capacity
1, population environmental carrying capacity: a certain period of time, a certain geographical area is able to maintain the maximum number of people to support.
Population: a certain period of time, a certain geographical area is able to maintain the maximum number of people.
Reasonable population capacity: the number of people that can be sustainably supported. The reasonable capacity of the population is smaller than the carrying capacity of the population.
2. Factors affecting the population capacity of the environment (environmental carrying capacity): resource status, productivity level, openness and consumption level.
4. Regional Culture and Population
Chapter 2: Spatial Structure of Cities and Urbanization
I. Spatial Structure of Cities
1. Functional Districts of Cities - Clustering of the Same Types of Urban Land Use
(1) Commercial Districts: Located at the center of the city, on both sides of the main transportation routes - convenient for transportation, and on both sides of the main transportation routes - convenient for transportation, and on both sides of the main transportation routes - convenient for transportation. Both sides of the trunk line - convenient transportation, developed communications, large flow of people; strong ability to pay rent.
★Central Business District (CBD): densely built, high-rise buildings, convenient transportation - limited area, but high demand
(2) Industrial area: generally located in the urban fringe, convenient transportation, most of the rivers or railroads and highways passing through.
(3) Residential area: the most widespread land use in the city.
(4) Cultural District: generally requires a beautiful environment, away from industrial and commercial areas. Urban construction should pay attention to the protection of cultural relics and monuments.
2. Reasons for the formation of geographical and functional zoning of cities: historical factors, economic factors, social factors, administrative factors
3. City size and territorial structure, scope of services
★Small cities: the territorial structure of the differentiation is not obvious, the provision of fewer types of services, low-level, small service scope.
★Large cities: clear differentiation of geographical structure, providing a wide variety of services, high level, large service scope.
Second, the influence of the city's location factors
(a), the natural aspects
1, terrain - the plains of the city density
2, climate - warm and humid climate of the region of the city density
2, climate - warm and humid region of the city density
3, rivers - the water supply and transportation functions of rivers determine the location of cities.
(2) socio-economic aspects
1, the agricultural base
2, transportation conditions: coastal, along the river, along the railroad line, along the highway can form the urban axis. Most of the northern cities are at the confluence of avenues.
★Changes in transportation routes can have an impact on urban development. (e.g. Yangzhou: when the canal was navigable - boom, after the canal was silted - bust).
3. Politics (e.g. administrative center), military defense, religion, science and technology, and tourism can also contribute to the formation and growth of a city.
Three, urbanization
1, the signs of urbanization: ① the increase in urban population, ② the proportion of urban population in the total population rose, ③ the expansion of the size of urban land. The most important indicator is the percentage of urban population in the total population.
2, after the end of the Second World War, urbanization is characterized by: ① the development of large cities faster than small cities; ② the number of large cities is increasing; ③ more than one million people in the megacities are developing fast.
3, the urbanization of developed countries
① Characteristics: early start, high level, slow speed, the phenomenon of reverse urbanization.
② Reasons for the reverse urbanization: increased demand for environmental quality, and the gradual improvement of infrastructure in rural areas and small towns."
4. Urbanization in developing countries
① Characteristics: late start, low level, fast speed, and obvious trend of large urbanization.
② China's urbanization lags behind industrialization.
③ The urban development is unreasonable: the rapid expansion of large cities, the slow development of small and medium-sized cities, and the concentration of population in a few large cities.
5, the general law of urbanization: urbanization - suburban urbanization - reverse urbanization - re-urbanization
Four, urbanization on the natural environment Impact
1. Impact of urbanization on the natural environment
(1) Impact on the climate: heat island effect, rain island effect, peri-urban thermal circulation, serious air pollution
(2) Impact on hydrology: on groundwater - the amount of infiltration is reduced, and the scope and depth of the groundwater leakage area is increased.
On the river water - slope flow water flow speed up, the river catchment time is shortened, more likely to form flood peaks.
On water quality - urban industrial wastewater, domestic sewage caused by pollution of urban water sources.
(3) Impact on biology: single variety of lawns and artificial forests; destruction of biological habitats and reduction of biological diversity.
2, protect and improve the urban environment - "eco-city"
① Establish satellite cities, develop new areas and decentralize urban functions.
② Improve urban transportation and living environment. Widen the main roads, build a ring road, build elevated highways, subways, light rail transportation.
③ Protect and manage the urban environment. Greatly strengthen the greening construction.
V. Regional Culture and Urban Development
Chapter 3 Human Productive Activities and Regional Connections
I. Agricultural Location Factors
1. Natural Factors (Climate, Water, Topography, and Soil): Modification - Greenhouse Agriculture, Terracing, Fertilizer, Watering.
2. Socio-economic factors (market, transportation, land rent, policy, labor)
★Market determines the type and scale of agriculture.
★The development of transportation conditions (especially preservation and refrigeration technology) has led to a geographical expansion of the influence of the market on agricultural location.
3. Technological factors (breeding, machinery, fertilizers, pesticides)
★Breeding of good seeds (high-yielding, drought-resistant, cold-resistant, storage-resistant and other varieties): conducive to the expansion of planting area.
★Mechanization: can improve labor productivity
★Application of fertilizers, pesticides, etc.: can increase the yield per unit area.
Two, the main geographical types of agriculture
1, commercial grain agriculture
(1) distribution: mainly in the United States, Canada, Australia, Argentina, Russia and other countries.
(2) Main varieties: wheat, corn (dryland crops, easy to mechanize production).
(3) Formation conditions: ★Natural conditions: flat terrain, vast arable land, sparsely populated.
★Socio-economic conditions: well-developed transportation, high level of technology
★Technological conditions: high degree of mechanization.
(4) Characteristics: large-scale production; high degree of mechanization; family farms are dominant
2. Rice cultivation:
Distribution East Asia, Southeast Asia, South Asia Monsoon Zone
Typical geographic regions
Asia Location conditions Climate Monsoon climate, rain and heat, suitable for rice growth
Terrain Lower plains of the rivers or river mouths Delta, flat, deep soil, good for farming
Labor force (labor-intensive agriculture) Densely populated, abundant labor force, good for intensive cultivation
History Long history of cultivation, rich tradition
Main characteristics Characteristics Reasons for formation
Small-scale farming Households, little arable land per capita
High yields, low commodity rates Intensive cultivation, low commercial rates. Low commodity rate Precision farming, but many rural people, self-sufficiency is the mainstay
Low level of mechanization Low level of economy, manual labor is the mainstay
Large amount of waterworks Monsoon climate, frequent floods and droughts
Low level of science and technology Long history, rich experience in tradition
3. Mixed agriculture
(1) Mainly mixed agriculture with livestock and cereals. The production of kitsang in China's Pearl River Delta is mainly a mixed agriculture of fisheries and forestry.
(2) Distribution: Europe, North America, Australia ("countries riding on the back of a sheep", "sitting on a mine cart") and so on.
(3) Characteristics (Murray-Darling Basin's "wheat-sheep belt" is an example)
① Benign agro-ecosystems:
★ Mutual benefits: planting provides fodder for animal husbandry, and animal husbandry provides fodder for livestock. Livestock provide feed, livestock provide fertilizer for planting
★ fallow and crop rotation, (conducive to the restoration of soil structure, improve soil fertility), planting, pasture.
② effective and reasonable farming arrangements: wheat farming (sowing May-June, harvesting November-December) formal grazing idle time.
③ Flexible production options: according to the market to determine whether to plant more wheat or more grazing sheep.
4, other agricultural geographic types
Territorial types Distribution areas Reasons for formation Main features
Migration agriculture Certain primitive tribal areas Low level of productivity, "slash-and-burn" Impact on biodiversity; deterioration of the climate
Dairy farming Developed countries, China's major cities around
Dairy industry, etc. Developed countries with high levels of urbanization. etc. High level of urbanization in developed countries, economically developed and concentrated population in large cities, high demand for milk and its products High rate of commodities; high level of mechanization;
Highly influenced by the distribution of cities;
High degree of intensification.
Three, the impact of agricultural production activities on the geographic environment
1, the impact on living things: ① cultivation of arable land, deforestation, etc.; ② artificial cultivation of good seeds; ③ overgrazing leads to the destruction of pasture, desertification; ④ pesticide application will cause contamination of agricultural products, resulting in a decline in the quality of agricultural products.
2, the impact on the soil: ① water irrigation leads to soil salinization; ② long-term application of chemical fertilizers will make the soil agglomeration, acidic and hard.
3, the impact on the climate: deforestation and afforestation, the construction of reservoirs and diversion of water for irrigation have changed the nature of the subsurface, changing the atmospheric heat source and water conditions.
4, the impact on hydrological characteristics: ① construction of reservoirs and diversion of water for irrigation: change the flow process of river runoff;
② reclamation of terraces, deforestation and afforestation: affect the river sand content.
Four, industrial location factors
1, factors affecting industrial location
(1) natural factors: minerals, land, water, climate and so on.
(2) economic factors - close to raw materials, fuels (such as non-ferrous metal smelting, heavy chemical industry base), markets - saving freight costs.
(3) labor and technology: industries requiring a large number of laborers, where wages account for a higher proportion of product costs (labor-intensive industries), and factories are to be laid out where there is a large pool of cheap labor. Technology-intensive industries are to be located close to places where higher education and science and technology are well developed.
(4) Industrial and agricultural base and collaboration conditions: including production collaboration and social collaboration
(5) Environment: industrial layout should pay attention to economic, social and environmental benefits. ① wind direction ② water ③ distance from the city
2, industrial location factors change:
(1) the impact of raw materials on the factory gradually weakened, the market impact on the location of the factory is gradually strengthened. Reason: the raw materials used in industry is more and more wide range, the improvement of transportation conditions;
(2) transportation: coastal ports along the river, railroad hubs, areas along the highway, the industry has a great attraction (in recent years, a number of developed countries transportation has been quite perfect, transportation is no longer the main factor in their considerations);
(3) information and communication network accessibility is becoming more and more important as a factor of industrial location;
(4) the influence of the quality of labor force is gradually increasing.
3. Types of industrial location
Industrial types Industrial characteristics Principles of location selection Main industrial sectors (examples)
Raw material oriented Raw materials are inconvenient for long-distance transportation or the cost of transporting raw materials is high Close to raw material sources Extractive industries, sugar industry, aquatic products processing industry, fruit processing industry, etc.
Power oriented Large amount of energy is consumed Close to energy bases Non-ferrous metal smelters
Market-directed Inconvenient or costly to transport products close to consumer markets Bottled beverages, furniture, printing, petroleum processing, etc.
Labor-directed Requires a large amount of labor close to areas with a large pool of cheap labor General apparel, electronic assemblies, bags and belts, umbrellas, shoes, etc.
Technology Pointing type High technological requirements, close to the higher education and science and technology developed areas, integrated circuits, precision instruments, etc.
V. Formation of industrial territories
1. Industrial agglomeration and the formation of industrial territories
(1) the leading factors leading to the agglomeration of: roads, water supply, power supply, and other infrastructural facilities; cheap labor; distribution of resources and energy and so on.
(2) the benefits of agglomeration (role) - economies of scale - (reduce costs and increase profits)
① can strengthen the exchange of information and technical collaboration between enterprises;
② reduce the transportation of intermediate products Reduce the transportation cost and energy consumption of intermediate products;
③ *** with the use of industrial zones, roads, water supply, power supply, communications and other infrastructure, saving investment in production and construction;
④ Favorable centralized treatment of environmental pollution in the production process.
2, industrial decentralization and industrial territorial linkage
(1) the reason for industrial decentralization: in order to give full play to the location advantages of different places (such as multinational corporations in the global search for the best location).
(2) the conditions of industrial decentralization: ① modern means of transportation - convenient, fast, cheap;
② modern communication technology and means - the world's "simultaneity
In the case of the "simultaneity" of the world, modern technology and means of communication.
VI. Traditional Industrial Zones
1. The dominant factor in location selection: traditional industrial zones are mostly formed and developed on the basis of abundant coal and iron resources.
★China's Anshan Iron and Steel development conditions: rich coal and iron resources, convenient transportation
★China's Baosteel development conditions: convenient transportation, broad market (iron ore is mainly imported from Australia, India and other countries)
2, problems: ① heavy industry is the mainstay of the production structure is single;
② raw materials, energy consumption, transportation, large. Economic efficiency is declining;
3) Serious environmental pollution and so on.
3. Solution Measures (Take the Ruhr Area of Germany as an example)
(1) Adjustment of Economic Structure: Developing new industries and tertiary industries, transforming the coal and iron and steel industries, and promoting the diversification of economic structure
(2) Development of Science and Technology: Developing science and technology, promoting tourism, prospering the economy, and promoting sustainable development
(3) Optimization of Environment: Eliminating pollution, planting trees, and landscaping the environment. Planting trees to beautify the environment
4. Transformation of resource-exhausted cities (industrial zones): For resource-exhausted cities, the city's development history and urban resources (whether minerals, land and human resources) are different, so you can't go on a fixed pattern, and you have to carry out economic transformation in accordance with your own characteristics. For example, the direction of transformation of Datong, Shanxi Province is mainly focused on tourism, deep processing of coal and new industries, the transformation of Pingdingshan, Henan Province, in addition to the coal chemical industry outside the sea development of salt chemical industry.
5, China's four major industrial bases
Characteristics Favorable conditions Unfavorable conditions
Liao-Zhongnan region Heavy industrial base rich in coal and iron resources, convenient transportation, lack of water resources
Beijing-Tianjin-Tangshan region the largest integrated industrial base in the north of China rich in iron, petroleum, sea salt resources, convenient transportation, close to the Shanxi energy bases, the unity of the power grid, lack of water <
Shanghai, Ningbo and Hangzhou The largest comprehensive industrial base in China Long history and strong industrial base; convenient transportation; strong technical force; abundant resources Lack of conventional energy resources
Pearl River Delta An integrated industrial base mainly for light industry Close to Hong Kong, Macao and overseas Chinese, which is easy to attract foreign investment; early development of special economic zones, which has technological and managerial advantages; abundant labor force Conventional energy resources Lack of conventional energy resources
VII. Emerging Industrial Zones
1. Major emerging industrial zones: Silicon Valley of the United States, Silicon Island of Japan, etc.
2.
2, the dominant factors in the choice of location: developed science and technology, convenient transportation (highways and airports), beautiful environment
VIII, the impact of industrial production activities on the geographic environment
1, the impact on the atmosphere: the arbitrary emission of industrial emissions caused by atmospheric pollution.
(1) global warming: the massive burning of fossil fuels, massive deforestation, so that the concentration of CO2 in the atmosphere increases
(2) acid rain: the burning of coal discharged a large number of SO2 caused. China - sulfuric acid type acid rain, developed countries - nitric acid type acid rain
(3) Ozone layer destruction: the use of refrigerators and refrigeration equipment in factories, mines, homes, etc., which discharges a large amount of hydrochlorofluorocarbons (HCFCs).
(4) Photochemical smog: car exhaust emissions of hydrocarbons, nitrogen oxides, etc. in the role of ultraviolet light, photochemical reactions will occur.
★ Governance Ideas: Reduce the emission of harmful gases -
① Improve the composition of energy consumption: the development and utilization of clean energy such as hydroelectric energy; the development and utilization of new energy sources such as solar energy and nuclear energy.
② Improve the efficiency of energy use: technological transformation and equipment upgrading
③ Reduce the emission of harmful substances: comprehensive utilization, cleaner production, meet the emission standards, and find substitutes
2, water pollution: arbitrary discharge of industrial wastewater caused by the pollution of the water body - heavy metal contamination, the water body's Eutrophication
3, solid waste pollution
nine, production activities in the territorial links - including transportation, communications, commercial trade, etc.
1, the importance of: communicating between different territories, to promote the flow of people, logistics, information flow.
①Political significance - conducive to people's contacts and cultural exchanges, and promote national unity; conducive to the consolidation of national defense and security.
②Economic significance - to promote the development of resources, resource advantages into economic advantages; to promote the production and circulation of goods, and promote economic development.
2, the main modes of transportation: railroads, highways, waterways, aviation and pipelines
3, communications: including postal (transfer of letters, goods, etc.) and telecommunications (transfer of sound, image, diagrams, etc., including telegraph, telephone, Internet).
4, the conditions for the formation of commercial centers: ① stable source area of goods, ② stable sales area, ③ well-developed transportation.
X. Transportation Layout
1. Main Location Factors: Economic Factors; Natural Factors (Topography, Rivers, Natural Disasters, etc.); Technical Factors
★ The overall direction of the line is determined by economic factors, while the specific direction of a section may depend on the topography, geology or technical conditions.
2. Changes in location factors: In the past, natural factors were the most important influencing factors; as technology advances, economic factors are becoming more and more important.
3, the main location factors of Shanghai port: water conditions (navigation conditions, berthing conditions), land conditions (port building conditions, hinterland conditions, based on the city)
4, the construction of airports: ① to have a flat and open terrain with appropriate slope to ensure drainage; ② to have good geological conditions to ensure the stability of the foundations; ③ to avoid low wetlands; ④ to maintain an appropriate distance from the city Distance: the site is wide, the city has a smoke screen, etc.
5, highway construction: ① plain area: less occupy good land, avoid swampy land, deal with the relationship with farmland and water conservancy facilities and town development.
2 mountainous areas: in the steep slopes into a "zigzag" bend, the road in the valley should avoid steep slopes. Make full use of the natural conditions, avoid the topography, geology, hydrology, complex conditions of the lot.
XI, changes in the mode of transportation and layout of the impact on settlements and commercial outlets
1, changes in the mode of transportation and layout of the impact on settlements
(1) Transportation and the formation of settlements: convenient transportation is conducive to the development of trade and commerce in the place, usually form a larger settlements.
(2) transportation and spatial layout of settlements
① the impact of different modes of transportation on the spatial layout of settlements: the south is mainly waterway transportation, settlements in front of the water layout
② the impact of different environments on the spatial layout of settlements
★ the terrain of the north is flat and open, settlements are mostly in the form of a cluster, the shape of the regular, the road in a checkerboard pattern.
★The plains in the south with dense rivers, the settlements are distributed along rivers, railroads and highways, and the layout is in the shape of a belt.
(3) Transportation and distribution of towns and cities: the beginning and end of river navigation, and the intersection with other transportation routes often form towns and cities.
(4) the impact of changes in the mode of transportation and layout of settlements: such as changes in the status of canal navigation and the rise and fall of Yangzhou, the migration of urban centers.
2, changes in the mode of transportation and layout of the impact on the commercial network
(1) the impact of transportation on the commercial network: convenient transportation, conducive to the distribution of people and logistics.
(2) The impact of changes in transportation and layout on commercial outlets
★With the development of highways, many businesses are clustered in the combination of highways and cities.
★With the development of transportation and modern logistics, various types of specialized markets, supermarkets, chain stores, etc. appear.
★With the improvement of urban transportation and the expansion of people's travel range, some multi-functional large-scale shopping and leisure centers were born.
★The development of electronic computers, network technology, online shopping, e-commerce, unmanned vending, etc. have been developed.
Chapter 4: Coordinated Development of Humanity and the Geographic Environment
I. The Historical Evolution of the Development of Ideas on the Relationship between Humanity and the Earth:
1. Worship of Nature - the civilization of hunting and quarrying - human beings and nature are in a relationship of fear and dependence;
2. p>
2, transformation of nature - agricultural civilization - the dependence of man on nature is greatly weakened, and antagonism is enhanced;
3, conquest of nature - industrial civilization -The relationship between man and the earth presents an overall disharmony, and the contradiction between man and the earth is rapidly intensified;
4. Seeking the coordination between man and the earth -Today's society -Harmonious development of the population, resources, and the environment
The main environmental problems faced by mankind
1, environmental problems - primary and secondary environmental problems
★Rational development and utilization of resources:
①Renewable resources: the key to "rational development
①Renewable resources: the key to the "rational development" - control the intensity of development, protection and promotion of renewal
②Non-renewable resources: the key to the "rational utilization" - conservation and comprehensive utilization, find new alternatives and comprehensive utilization, looking for new substitutes
2, the causes of environmental problems - population pressure, irrational use of resources, unilateral pursuit of economic growth.
(1) Human production and living activities consume resources faster than they can be regenerated;
(2) The amount of waste discharged into the environment by human beings exceeds the environment's self-purification capacity.
★The environmental problems in developing countries are more serious than those in developed countries because (1) the environment is under the double pressure of development and population; (2) the low level of economic technology does not have enough capacity for environmental protection; (3) developed countries have transferred heavily polluting industries to developing countries.
(C) the main environmental problems - environmental pollution, ecological damage
1, environmental pollution:
(1) atmospheric pollution: global warming, acid rain, the destruction of the ozone layer - sources of pollution: industrial production, Family life, transportation
①Global warming -
★The main greenhouse gases are CO2, CH4, N2O, O3 and so on. Volcanic ash, afforestation can reduce the warming trend.
★ Hazards: coastal - melting glaciers, rising seas, inundation of coastal lowlands, reduction of arable land, increased storm surges and salinization.
Mid-latitudes - increased evaporation, degradation of arable land and grasslands, expansion of desertification, and shrinking of agricultural acreage.
② Acid rain (fog, snow) - "air death": atmospheric precipitation with a pH value less than 5.6.
★Hazards: effects on water, soil, organisms, and buildings.
3) Ozone Layer Destruction
(2) Water Pollution: industrial wastewater; agricultural sewage (from pesticides, fertilizers); domestic sewage (various washing water, including nitrogen, phosphorus, etc.)
(3) Soil Pollution:
(4) Solid Waste Pollution: industrial wastes, agricultural wastes, construction wastes, and municipal wastes
★Hazards: Pollution of the atmosphere, pollution of water, pollution of soil, affecting health and spreading disease
★Disposal: classification and recycling, comprehensive utilization; landfill; composting (fermentation, high temperature sterilization); incineration (power generation), etc.
2. Ecological damage: disruption of the ecological balance - the reduction of biological species, destruction of forests and grasslands, land desertification, soil erosion, etc.
(1) Sharp decline in biological species
①Status quo: Biodiversity is being destroyed more and more quickly. (Large-scale species extinction occurs in the tropical rainforests).
★ Role of living things: ①Economic- Provide food, timber, industrial raw materials, etc. for human beings.
②Ecological aspects - to promote the circulation of materials and energy flow in the ecosystem, constituting a life support system.
②Causes: indiscriminate logging, overhunting, environmental pollution. (Invasion of foreign organisms can also lead to species extinction)
③Harms: Destruction of biodiversity, breakage of the food chain and dislocation of the ecological balance.
(2) Destruction of forest resources - forests are known as the "lungs of the earth", forests are the main body of the terrestrial ecosystem.
Causes of the decrease in forest area: logging, land clearing, mining, fuel wood collection, grazing and air pollution
(3) Decrease in wetlands - Wetlands are known as the "kidneys of the earth"
1) Role of wetlands: Economic Role of wetlands: economic--provide food, water, shipping, breeding, tourism, irrigation, etc.
Ecological role--protect biodiversity, nourish water, store floods and prevent droughts, and regulate the climate
(Peat in wetlands contains a large amount of undecomposed organic matter, which does not participate in the atmospheric CO2) (wetlands in the peat contains a lot of undecomposed organic matter, do not participate in the atmospheric CO2 cycle, become a charcoal reservoir, can alleviate the "greenhouse effect")
② wetlands reduce the causes: soil erosion led to sediment deposition; water diversion and irrigation led to a reduction in the amount of water into the lake (swamp); the enclosure of lakes (sea) to create a field, so that the area of lakes, shoals, and reduce the eutrophication of the water column, so that wetland functions weakening or even loss of wetland functions.
(4) Land Desertification
①Desertification manifestations: land sanding, rocky desertification and secondary salinization caused by the shrinkage of cultivated land, forest land, grassland and wetland.
② main distribution areas: arid, semi-arid, semi-moist areas
③ causes of desertification in the northwest:
★ natural causes: arid climate, sparse vegetation, loose soil; windy (rainstorms, rodents, etc.)
★ man-made causes: the surge in population led to excessive agricultural cultivation, excessive woodcutting and mining, overgrazing, irrational use of water resources
④ the main measures to prevent and control: cultivated land, forests, grasslands, the shrinkage of land caused by sand, stone desertification and secondary salinization. p>④Major measures to prevent and control:
Ⅰ. Controlling the number of people: It is conducive to alleviating the contradiction between people and land, and establishing an ecosystem in which population, resources and environment develop in a coordinated manner
II. Ecological restoration and construction:
★Using biological and engineering measures to prevent wind and fix sand
◇Oasis areas: sealing sand and grass (periphery); planting trees and forests (frontier); and setting up farmland protection forest networks (interior).
◇In areas lacking water sources: use firewood and grass and other materials to set up sand barriers in areas of quicksand to fix and block quicksand.
★Adjusting the land use structure and rationalizing the allocation of agriculture, forestry and animal husbandry: planting trees and grasses, rational grazing, returning farmland to forests and grasses
★Multi-channel solutions to the energy problem: such as the development of new energy sources, the creation of charcoal forests, the construction of biogas pools, and the promotion of wood-saving stoves.
III. Rational use of water resources: improve farming and irrigation techniques, promote water-saving agriculture; rational allocation of water resources upstream, midstream and downstream of the river, taking into account the development of upstream and midstream, as well as downstream ecological protection.
(5) Secondary salinization of soil
①Distribution (China): North China Plain, Northeast China Plain, and on oases (desert areas irrigated by water sources).
② causes of secondary salinization: man-made: backward farming techniques, irrational irrigation (flood irrigation)
natural: arid climate, evaporation, salt is easy to gather on the surface
three, sustainable development
(1) the concept of sustainable development: to meet the needs of the present generation, but not to the detriment of future generations to meet the needs of their ability.
(2) the connotation of sustainable development - economic, social and ecological sustainable development
(3) sustainable development needs to follow the principles:
① principle of fairness: equity between generations, between generations, between humans and animals, between different countries and regions.
② The principle of sustainability: economic activities and social development must remain within the carrying capacity of resources and the environment.
③ Principle of ****similarity: The earth is a whole, and regional environmental problems are often transformed into global problems. Regional decisions and actions should contribute to the realization of the coordination of the global whole.
(4) Cleaner Production: Traditional methods of assessing the environmental impact of products focus only on end-of-pipe treatment. Cleaner production, on the other hand, assesses the extent of a product's impact on the environment from the entire process of raw material extraction - production - consumption - and waste disposal.
4. China's Sustainable Development Path
1. The necessity of China's sustainable development path:
4. Huge Population Pressure:
5. Worrisome Resource Scarcity: Population Pressure, Rapid Economic Development, and Low Resource Utilization Rate.
⑥ Deep environmental crisis: environmental pollution is spreading rapidly from cities to rural areas, and the scope of ecological damage is still expanding. The zone of extreme ecological crisis is distributed in the eastern part of the country, which is densely populated, economically developed and characterized by frequent human activities.
2. China's strategic framework for sustainable development: In March 1994, the State Council issued China's Agenda 21
3. Eco-agriculture is a model of sustainable agricultural development with Chinese characteristics. Measures to build eco-agriculture in the village of Liuming:
① Adjustment of agricultural structure: from a single plantation to the comprehensive development of agriculture, forestry, animal husbandry, sideline and fishery
② Carrying out the comprehensive utilization: centering on agricultural and livestock products, developing feed processing factories and food processing factories.
③ Wide-open sources, the development and utilization of new energy: the use of biogas - raw materials from straw, animal and human feces and urine, biogas, biogas residue to return to the field or fish farming. (Understanding the comprehensive recycling map of agricultural and sideline products in Liuminying Village)