Page 71 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

6. Explain how climate affects the types of vegetation.

Ans. Climate affects the types of vegetation in several ways:
Temperature: Different plants thrive in different temperature ranges. For example,

tropical plants need warm temperatures year-round, while temperate plants can
handle a range of temperatures and cold winters.

Precipitation: The amount and distribution of rainfall determine which plants can
grow in an area. Arid regions with low rainfall support drought-resistant plants like

cacti, while regions with abundant rainfall support lush, dense forests.
Seasonal variations: Seasonal variations affect vegetation types. For instance, regions

with distinct seasons have deciduous trees that shed leaves in winter, while regions
with mild, consistent temperatures may have evergreen trees that retain leaves year-

round.
Humidity: High humidity levels support the growth of certain plants like ferns and

mosses, while low humidity conditions are better suited for plants with adaptations
to conserve water.

Sunlight: The amount of sunlight affects plant growth and types. Some plants require
full sunlight to thrive, while others can grow in shaded areas.

Wind: Strong winds can affect vegetation by causing physical damage or increasing
evaporation rates. Plants in windy areas often have adaptations like deeper root

systems or smaller, tougher leaves.
7. How does soil erosion occur?

Ans. Soil erosion occurs due to factors given below :
Wind : Wind is a major factor for soil erosion. When strong winds blow in the areas

where the land is not covered with grass or plants, it blows away the topsoil along
with organic matter, which leads to soil erosion.

Water : When it rains in hilly areas, soil is washed away towards the plains making
the land on hills barren and infertile. During rainfall, the raindrops hit the surface of

the soil, bringing them down and dispersing the fertile particles and washing them
away in runoff.

Deforestation : It is also one of the major causes of soil erosion. Plants and trees help
in maintaining the structure of the soil by holding the soil with their roots, reducing

the risk of soil erosion. Areas with less vegetation are prone to soil erosion. Trunks of
trees also slow down the speed of moving wind and water.

Overgrazing : When cattle graze repeatedly on the same field, they tend to eat the
plants and grasses along with their roots, making the topsoil vulnerable to wind and

water and making way for soil erosion.

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