20 19 geography knowledge points in the second volume of Grade 8

Part I: Loess Plateau Test Site. World loess accumulation area

1. Scope: Taihang Mountain in the east, Wushaoling in the west, Qinling Mountain in the south, Great Wall in the north, spanning Shanxi, Shaanxi, Gansu, Ningxia and other provinces.

2. Landscape: loess tableland, loess beam and loess headland.

3. Genesis: Aeolian theory holds that loess was blown from deserts and Gobi in Central Asia and Mongolia.

Test site 2, serious soil erosion.

1. Causes of soil erosion

Natural factors:

(1) Terrain: The ground is broken, with high valley density, less flat land and many slopes.

(2) Vegetation: The surface is bare, lacking the protection of vegetation.

(3) Climate: Precipitation is mainly concentrated in July and August, with heavy rain.

(4) Loess properties: the structure is loose, and many substances are easily soluble in water.

Human factors: reclamation, mining, road construction and other activities make the surface loose.

consequence

Soil erosion takes away the fertile soil on the surface and reduces crop yield; Increase, expand and deepen the valley, thus reducing the cultivated land area; Transporting a large amount of sediment to the lower reaches of the Yellow River brings great difficulties to river regulation and flood control.

Test center 3. Fragile ecological environment

1. Fragility: The loess plateau has a broken terrain and a relatively dry climate, which not only causes serious soil erosion, but also causes frequent natural disasters. It is difficult to recover after the ecological environment is destroyed.

2. The most important natural disasters: drought and flood.

Test site IV. Ecological construction

On the one hand, biological measures such as planting trees and grass are combined with engineering measures such as terraced fields and earth dams to control soil erosion; On the other hand, reasonable arrangements should be made for production activities, such as returning farmland to forests and grasslands on steep slopes, and reducing the number of grazing livestock in overgrazing areas.

Chapter II: Three Provinces in Northeast China

1. location

Northeast China, including Heilongjiang, Jilin and Liaoning provinces, is located in the northeast of China, bordering North Korea and Russia, and most areas are in the middle temperate zone.

2. Terrain and climate

Surrounded by mountains, the endless plain landform. The climate is characterized by long and cold winters and short and warm summers. The large-scale distribution of snow and frozen soil in winter changes the distribution of water throughout the year, ensures good water content of soil, and is beneficial to agricultural production. However, the heat condition is insufficient, and the first frost and cold damage affect the agricultural harvest.

3. Important agricultural and forestry production bases

The main grain crops are corn, spring wheat, winter wheat and miscellaneous grains, and the output of spring wheat ranks first in the country. The main cash crops are: soybean, beet and flax, and the output of beet in Northeast China accounts for more than half of the country. Liaodong Peninsula is an apple producing area at home and abroad. The shelterbelt in the western part of the Northeast Plain is the current shelterbelt in China, which is 800 kilometers long and is known as the "Green Great Wall". Northeast mountainous area is called "Northeast Linhai", which is rich in forest resources. It is a forest cutting base in China and a Korean pine forest area in the world. Minks, pilose antler and ginseng produced in forest areas are called "three treasures" in Northeast China.

4. Northeast China is rich in oil, coal and iron resources, which is the most oil-producing area in China. The main oil fields are Daqing, Jilin and Liaohe. Daqing Oilfield is the current crude oil supply base in China. The main coal mines are Fushun, Jixi and Hegang. The famous iron mines in China are Anshan and Benxi in Liaoning.

5. Industrial system dominated by heavy industry The three northeastern provinces have basically formed an industrial system dominated by heavy industries such as steel, machinery, petroleum, coal and chemistry.

6. Dense railway network

The main railway lines are Binzhou Line, Suibin Line and Harbin-Dalian Line. Shenyang is a city in the northeast of China. Dalian Port is a seaport in the northeast. Songhua River is the most important inland waterway in northeast China. Now the longest expressway from Shenyang to Dalian in China has been completed.

Chapter III: Regional Characteristics

First, the basic methods of regional characteristics

Regional characteristics refer to the geographical characteristics formed by the comprehensive action of various natural geographical elements (location, topography, climate, hydrology, soil, vegetation, natural resources, etc.). ) and human geography elements (population, industry, agriculture, cities, transportation, etc. ) in a specific area. The methods of analyzing regional characteristics mainly include comprehensive analysis and comparative analysis:

1. Comprehensive analysis: Understand and analyze the characteristics of a region as a whole. Regional characteristics are the overall characteristics formed by the mutual influence, mutual restriction and mutual connection of various geographical elements, which need to be understood as a whole through comprehensive and systematic analysis. In the process of analysis, we should be good at grasping the dominant factors, such as the cold climate is the dominant factor in the formation of Antarctic regional characteristics, which directly affects other natural characteristics (strong wind, abundant fresh water resources and wind energy resources, etc.). ) and the human characteristics of this area (no permanent population).

2. Comparative analysis: Through the comparison, contrast and analysis of natural geographical elements and human geographical elements in different regions, find out their similarities and differences, so as to have a deeper understanding of the characteristics of a certain region. For example, the Qinling-Huaihe line is the geographical dividing line between the southern and northern parts of China.

Second, the analysis of regional characteristics

Regional characteristics are the embodiment of the mutual connection and interaction between natural elements and humanistic elements in this area. The comprehensive analysis of regional characteristics includes the analysis of regional elements (geographical location, topography, climate, hydrological system, economic characteristics, etc.). ), regional characteristics and causes. The comprehensive analysis of the geographical environment characteristics of a certain area is mainly considered from three aspects: regional geographical position, regional natural geographical environment and regional human geographical environment. Details are as follows:

1. Analysis of regional geographical location characteristics

(1) Absolute position: it is mainly to analyze and judge the latitude and longitude position of a certain area, that is, to determine its regional position and scope according to the latitude and longitude of a geographical thing. For example, if a place is located in 10 s ~ 40 s, 120 e ~ 150 e, it can be judged.

(2) Relative position:

① Land and sea location: mainly including mainland inland, mainland west coast, mainland east coast and islands surrounded by ocean. It is necessary to analyze and judge the location of the region from the islands, peninsulas, the east and west coasts of the mainland, the interior of the mainland and the east and west coasts of the ocean. If a continent is located in the southern hemisphere, the Pacific Ocean to the west and the Atlantic Ocean to the east, it can be determined that it is a South American continent.

② Location of mountains and rivers: Analyze and judge the location of this area from the distribution and trend of mountains, the form and flow direction of water system, etc. For example, a place is located on the west side of Taihang Mountain, on the convex bank of a river, etc.

③ Political and geographical location: According to the outline of a country or region, or the outline of neighboring countries and provinces, analyze and judge the location of this region. ④ Geographical location of traffic: analyze and judge the location of the area from the main modes of traffic and the distribution of center lines and points in the traffic network.

2. Analysis of physical and geographical characteristics

The specific geographical location of a region makes it form a specific combination of water and heat, that is, climate characteristics. Climate affects hydrology, biology, soil, etc. These elements constitute the characteristics of the regional natural environment. The analysis of common physical geographical elements can be carried out from the following aspects:

(1) topographic features

Topographic elements

Mainly from the terrain type, altitude, surface fluctuation, terrain distribution, terrain height to describe.

Topographic elements

Mainly from the trend of surface fluctuation, there are two commonly used description languages: one is high in direction and the other is low in direction; The second is to tilt from one direction to the other.

Geological process

Internal forces mainly include crustal movement, magmatic activity and metamorphism. The external force mainly acts as erosion in the plateau and mountainous areas with large surface fluctuation, accumulation in the lower layer, running water in humid and semi-humid areas with more precipitation, and wind power in arid and semi-arid areas with less precipitation.

geologic hazard

Mainly refers to earthquakes, volcanic eruptions, landslides and mudslides.

(2) Climate characteristics: mainly from the types of climate, the distribution of climate elements, factors affecting climate, the impact of climate on animal and plant resources and rivers, and the relationship between climate and agricultural production (here mainly introduce two aspects).

① Climate type: mainly analyzed from latitude and longitude position and land and sea position. ② Distribution of climatic factors: mainly the distribution of temperature and precipitation. Generally, it includes two situations: first, the distribution of climate elements in a large area, that is, climate characteristics; Second, the distribution of climatic factors in local areas should be analyzed according to their natural geographical environment characteristics, such as more precipitation on windward slopes and less precipitation on leeward slopes; The sunny slope has a high temperature and the shady slope has a low temperature. ?

(3) River characteristics: mainly from the aspects of river system characteristics, hydrological characteristics and water resources development and utilization. ① Water system characteristics: mainly refers to the process, flow direction, water system ownership, river characteristics (valley width, riverbed depth, bend), river network density (number of tributaries, relationship between rivers and lakes), basin area (area size, water system arrangement), etc. (2) Hydrological characteristics: mainly refers to river flow, water level (flood season, dry season, cut-off period and dry season), sediment concentration, icing conditions (whether there are ice ages and ice storms), etc. (3) Development and utilization of water resources: hydropower resources are mainly developed in areas with large topographic relief, large river flow, large drop and rapid water flow in the middle and upper reaches of rivers; Inland navigation is mainly developed in areas with flat terrain, gentle water flow, wide rivers and stable water flow in the middle and lower reaches of rivers.

3. Analysis ideas of human geographical characteristics

Human beings exploit and utilize resources and energy from the natural environment, and develop agricultural production, industrial production, urban construction, transportation and commercial trade, thus forming the characteristics of regional human geographical environment. Common elements of human geography can be analyzed from the following aspects:

(1) agriculture: mainly from the aspects of location conditions, farming system or planting system (heat influence), crop type (heat and water influence), cultivated land type (water influence) and regional structure type.

(2) Industry: mainly from the industrial sector, industrial distribution, location conditions (such as the origin of raw materials, the relationship between factories and markets, technical and traffic conditions and layout requirements).

(3) Cities: mainly from the aspects of urbanization level, urban layout, urban location factors and urban environmental problems.

(4) Traffic: mainly analyze traffic lines and hubs, traffic network density, and main location factors affecting traffic layout.

(5) Environmental problems: comprehensive analysis is mainly made from two aspects: environmental pollution and ecological destruction. ① Environmental pollution mainly includes air pollution, water pollution, soil pollution, solid waste pollution, noise pollution, radioactive pollution and marine pollution. ② Ecological destruction mainly includes the destruction and waste of resources (land, biology, water and minerals) and environmental degradation (desertification, soil erosion and ecological balance destruction). At present, the main environmental problems should be analyzed from their present situation, causes, hazards and solutions.