Welcome to the Natural Environment!

In this chapter, we are going to explore the "stage" where all human life takes place. We will look at the shape of the land (landforms), the air around us (climate), and the water that flows through it (rivers). Understanding how these three things work together helps us understand why people live the way they do! This module is part of our journey into People and the Environment.

1. The Shape of the Land: Landforms

The Earth’s surface isn't flat. It has different shapes called landforms. In China and around the world, we group these into five basic types:

  • Plateaus: High, flat ground (like a table in the sky).
  • Mountains: Very high land with steep sides and sharp peaks.
  • Hills: Like mountains, but lower and more rounded.
  • Basins: Low areas surrounded by higher land (like a giant bowl).
  • Plains: Wide, flat lowlands—great for farming and building cities!

Reading a Mountain

When looking at a map, we need to identify different parts of a mountain. Think of these as the "anatomy" of the land:

1. Peak: The highest point.
2. Slope: The side of the mountain (can be steep or gentle).
3. Ridge: A long, narrow hilltop.
4. Saddle: A low point between two peaks (shaped like a horse's saddle).
5. Valley: A low area between hills or mountains, often with a river.
6. Spur: A piece of land that sticks out from the side of a mountain.

Map Skills: Contour Lines

How do we show a 3D mountain on a 2D paper map? We use contour lines. These lines connect places that are at the same height above sea level.

  • Lines close together = Steep slope.
  • Lines far apart = Gentle slope.
  • Quick Tip: If the contour lines form a "V" shape pointing downhill, it's a spur. If they point uphill, it’s a valley!

Calculating Gradient:
To find out how steep a slope is, we use this formula:
\( \text{Gradient} = \frac{\text{Vertical Interval (height difference)}}{\text{Horizontal Distance}} \)
We usually write the answer as a ratio, like \( 1 \) in \( n \).

2. The Air Around Us: Climate

Climate is the "average" weather of a place over a long time. To measure it, we look at several climatic elements:

  • Air Temperature: Measured in degrees Celsius \( (^\circ\text{C}) \).
  • Precipitation: Rain, snow, or sleet. Measured in millimetres \( (\text{mm}) \).
  • Air Pressure: Measured in hectopascals \( (\text{hPa}) \).
  • Wind: We measure Wind Direction (where it comes from) and Wind Speed \( (\text{km/h}) \).
  • Relative Humidity: How much moisture is in the air, shown as a percentage \( (\%) \).

China’s Climate and the Monsoon

China has a monsoon climate. A monsoon is a seasonal wind that changes direction.

In Winter: Cold, dry winds blow from the land toward the sea.
In Summer: Warm, wet winds blow from the sea toward the land, bringing lots of rain.

Temperature Pattern: In China, the south is generally warmer than the north. In winter, the temperature difference between north and south is very big, but in summer, most of China is quite warm.

3. Rivers: The Flow of Life

Rivers are natural flows of water. They usually start in high mountains and flow down toward the sea.

China’s Three Giant Rivers:

1. Changjiang: The longest river in China.
2. Huanghe: Known for carrying lots of yellow silt.
3. Zhujiang: The major river system in Southern China, near Hong Kong.

The Connection:
The topography (land shape) affects the rivers. Because China is high in the west and low in the east, most major rivers flow from West to East.

4. Living in Different Regions

China is divided into four major geographical regions. The natural environment in each region affects how people live:

  • North: Often colder and drier; people grow wheat.
  • South: Warmer and wetter; people grow rice and live near many rivers.
  • Northwest: Very dry; inland area far from the sea.
  • Qinghai-Tibet: Very high altitude (plateau); cold and thin air.

Key Takeaway: The environment (land, climate, water) decides what crops we can grow, what clothes we wear, and even how we build our houses!

5. Extended Learning (Going Further)

For those wanting to dive deeper into the "Why?"

Why is China’s climate different in different places?

Four main factors control the climate:

  1. Latitude: Places closer to the Equator (South) are warmer.
  2. Altitude: Higher places (mountains) are colder.
  3. Distance from the sea: Places near the ocean stay more moderate; places far inland are drier.
  4. Monsoon: Seasonal winds bring rain or dry air.

Human Impact on Rivers

While nature creates rivers, human factors change them. For example, human activities can cause differences in the way the Changjiang and Huanghe behave, such as how much water they carry or how much they flood.

Quick Review Box

Don't forget:
- 5 Landforms: Plateau, mountain, hill, basin, plain.
- Monsoon: Seasonal wind direction change (Winter = dry, Summer = wet).
- 3 Major Rivers: Changjiang, Huanghe, Zhujiang.
- Contour Density: Closely packed lines mean a steep slope!

Common Mistake to Avoid: Don't confuse "weather" (what's happening outside right now) with "climate" (the long-term pattern). In Geography exams, always use the term climate when talking about seasonal patterns!