Ecosystems - Standard 8 - General Science - Balbharati
Ecosystems
Exercise
Q. 1 Complete the following by using correct option.
a. Air, water, minerals, soil are physical factors of an ecosystem.
(physical, organic, inorganic)
b. River, ponds, ocean are aquatic ecosystems.
(land, aquatic, synthetic)
c. Man is consumer in an ecosystem.
(producer, consumer, decomposer)
Q. 2 Match the following.
| Producers | Ecosystem |
|---|---|
| Cactus | Desert |
| Aquatic plants | Aquatic |
| Mangroves | Creek |
| Pine | Forest |
Q. 3 Give my information.
a. Ecosystem
Ans. The world around us is made up of living and non-living factors. Living are called biotic factors while non-living are called abiotic factors. There is a continuous interaction between these living and non-living factors. Living organisms and their habitat, environment are correlated with each other. The structure which is formed due to these reciprocal relationships is called an ecosystem. Biotic and abiotic factors and their interactions form an ecosystem.
b. Biome
Ans. In some regions on earth, a large area has same climate and abiotic factors. The living organisms in those area are also similar. So a specific ecosystem developes in a vast area. Such large ecosystems are called 'Biomes'. These biomes contain many small ecosystems. Earth itself is a vast ecosytem. Two types of biomes are found on the earth. i. Land biomes ii. Aquatic biomes
c. Food web
Ans. One creature can be in many food chains, creating a food web in nature. This shows how different living things are connected and interact with each other in an ecosystem..
Q. 4 Give scientific reasons.
a. Plants in an ecosystem are called consumers.
Ans. Plants are known as producers because they undergo photosynthesis, a process where they use sunlight to produce their own food. Consumers, on the other hand, are organisms that consume other living organisms for their energy needs.
b. Large dams destroy ecosystems.
Ans. Large dams destroy ecosystems because; large dams can disrupt the natural flow of rivers. It leads to habitat loss for terrestrial organisms and impacts present aquatic organisms. It disrupts migration patterns and leads to the loss of biodiversity.
c. Rhinos were restored in Dudhwa forest.
Ans. Rhinos were restored in the Dudhwa forest because of conservation efforts like habitat restoration, protection from poaching, and breeding programs.
Q. 5 Answer the following.
a. What are the effects of increased population on ecosystems?
Ans. 1. Increased population stresses ecosystems. Rapid human consumption depletes natural resources.
2. Changing lifestyles and higher demands lead to overexploitation. Overexploitation causes environmental degradation.
3. Large waste amounts are generated.
4. The balance of ecosystems is harmed.
5. Well-being of both nature and people is threatened.
b. How is urbanization responsible for the destruction of ecosystems?
Ans.
1. Urbanization puts pressure on ecosystems.2. Increased construction and infrastructure development lead to habitat loss.
3. Expansion of urban areas results in deforestation and soil degradation.
4. Pollution from urban activities harms air, water, and soil quality.
5. Disruption of natural landscapes affects biodiversity.
6. Urbanization contributes to climate change.
7. Overall, it causes destruction and imbalance in ecosystems.
c. What are the reasons for war?
Ans. Differences and competition over land, water, mineral resources, or economic and political reasons lead to wars.
d. Explain the interactions among the factors of an ecosystem.
Ans. 1. Living organisms need different types of abiotic factors and they have different capacities to adapt with those abiotic factors. Some microbes need oxygen, while others don’t. Some plants need more sunlight, while others grow well in shade.
2. Each and every abiotic factor (air, water, soil, sunlight, temperature, humidity) affects the biotic factors in the ecosystem. The abiotic factors in an ecosystem decide which biotic factors will survive in it and what will be their number.
3. The proportion of abiotic factors in an ecosystem is always changing as biotic factors use or excrete abiotic factors.
4. Every biotic factor affects abiotic factors as well as other biotic factors around it. Every living organism in an ecosystem plays a particular role while living, moving in that ecosystem.
e. Differentiate between evergreen forests and grasslands.
Ans.
| Evergreen Forests | Grasslands |
|---|---|
| 1. Dense tree cover throughout the year | 1. Dominated by grasses and herbs |
| 2. Trees retain leaves year-round | 2. Seasonal variation in vegetation |
| 3. High biodiversity with various plant and animal species | 3. Primarily herbivores and fewer tree species |
| 4. Supports diverse wildlife, including mammals and birds | 4. Often adapted to fire, with some tree species having fire-resistant features |
| 5. Occurs in regions with consistent rainfall | 5. Can experience periodic droughts |
| 6. Soil tends to be rich in nutrients due to decomposition of leaves | 6. Soil quality varies, often nutrient-rich topsoil |
Q. 6 Describe the following pictures.
1.
Ans.
