Q1: Which of the following is not a factor responsible for soil erosion?
(a) Deforestation
(b) Heavy rainfall
(c) Planting cover crops
(d) Overgrazing
Ans: (c)
Planting cover crops is a method used to prevent soil erosion, not a factor causing it. Deforestation, heavy rainfall, and overgrazing can contribute to soil erosion.
Q2: Which type of soil is best suited for growing crops?
(a) Sandy soil
(b) Clayey soil
(c) Loamy soil
(d) Rocky soil
Ans: (c)
Loamy soil is a balanced mixture of sand, silt, and clay and is considered ideal for crop cultivation because it has good water retention and drainage properties.
Q3: What is the primary source of groundwater?
(a) Rivers
(b) Lakes
(c) Monsoon rains
(d) Percolation of rainwater
Ans: (d)
Groundwater primarily comes from the percolation of rainwater through the soil and into underground aquifers.
Q4: Which of the following is an example of natural vegetation in a tropical rainforest?
(a) Oak trees
(b) Coniferous trees
(c) Banana plants
(d) Maple trees
Ans: (c)
Banana plants are commonly found in tropical rainforests, which are characterized by lush, dense vegetation and a warm climate.
Q5: What is the term for the practice of breeding and raising fish in controlled environments?
(a) Aquaculture
(b) Horticulture
(c) Sericulture
(d) Apiculture
Ans: (a)
Aquaculture is the practice of cultivating and harvesting fish and other aquatic organisms in controlled environments such as ponds or tanks.
Q6: Explain the importance of afforestation in the conservation of natural vegetation.
Ans: Afforestation involves planting trees in areas where they have been cut down or where they did not previously exist. It is essential for the conservation of natural vegetation because it helps in restoring ecosystems, prevents soil erosion, maintains biodiversity, and mitigates climate change by absorbing carbon dioxide from the atmosphere.
Q7: Describe the role of wetlands in maintaining ecological balance and their significance for wildlife.
Ans: Wetlands play a crucial role in maintaining ecological balance by serving as habitats for a wide variety of plants and animals. They help control flooding, improve water quality, and act as nurseries for many aquatic species. Wetlands are also important for migratory birds and serve as stopover points during their journeys.
Q8: Explain how overgrazing can lead to land degradation.
Ans: Overgrazing occurs when there are too many livestock animals on a piece of land, and they consume vegetation faster than it can regrow. This can lead to land degradation as it causes soil erosion, decreases plant cover, reduces soil fertility, and leads to the spread of invasive species. It negatively impacts the health of the land and can result in desertification.
Q9: Discuss the factors that contribute to the pollution of water resources and its consequences.
Ans: Water pollution is caused by various factors, including industrial discharge, agricultural runoff, untreated sewage, and improper waste disposal. It leads to the contamination of water bodies, which can harm aquatic life and make water unsafe for human consumption. Waterborne diseases can spread, and ecosystems can be severely disrupted.
Q10: What are the advantages of rainwater harvesting, and how can it be implemented at the individual level?
Ans: Rainwater harvesting has several advantages, including reducing the demand on groundwater, preventing soil erosion, and providing a sustainable source of water. At the individual level, rainwater harvesting can be implemented by installing rooftop rainwater collection systems that direct rainwater into storage tanks. This harvested rainwater can then be used for various purposes, including watering gardens and flushing toilets, reducing the reliance on potable water sources.
Q11: Explain the significance of natural vegetation and wildlife in maintaining ecological balance. Provide examples of how human activities can disrupt this balance and suggest measures for conservation.
Ans: Natural vegetation and wildlife play a crucial role in maintaining ecological balance. They regulate the climate, support various ecosystems, and provide habitat for numerous species. Human activities, such as deforestation, habitat destruction, and pollution, disrupt this balance. For instance, the destruction of mangrove forests can lead to coastal erosion and loss of biodiversity. Conservation measures include creating protected areas, promoting sustainable forestry, and raising awareness about the importance of preserving natural habitats.
Q12: Discuss the factors influencing soil formation. Explain how soil erosion can adversely affect agriculture and suggest methods to prevent soil erosion.
Ans: Soil formation is influenced by factors like parent material, climate, topography, vegetation, and time. Soil erosion, the removal of fertile topsoil, can lead to reduced agricultural productivity. For instance, heavy rainfall can wash away topsoil, leaving infertile subsoil. Preventive measures include contour farming, terracing, and afforestation. Contour farming involves planting crops along the contour of the land to slow down water runoff. Terracing uses steps or benches to reduce the speed of water flow. Afforestation involves planting trees to stabilize the soil and prevent erosion.
Q13: Describe the concept of 'water cycle' in detail. Explain how human activities such as deforestation and pollution can disrupt this cycle and impact water resources.
Ans: The water cycle is a natural process that involves the continuous movement of water between the atmosphere, land, and oceans through processes like evaporation, condensation, and precipitation. Human activities like deforestation reduce the transpiration of water from trees, disrupting the cycle. Pollution from industries and agriculture can contaminate water bodies, affecting the quality of water available for various uses. This disruption can lead to water scarcity and environmental degradation. To mitigate this, we must practice afforestation to maintain transpiration rates and implement strict pollution control measures.
Q14: Explain the concept of 'biodiversity.' Discuss the importance of conserving biodiversity and provide examples of how human activities can threaten it.
Ans: Biodiversity refers to the variety of life forms, including species, ecosystems, and genetic diversity, in a particular region. Conserving biodiversity is essential because it supports ecological balance, provides ecosystem services (like pollination and nutrient cycling), and offers genetic resources for agriculture and medicine. Human activities such as habitat destruction, over-exploitation of resources, and pollution threaten biodiversity. For example, overfishing can lead to the decline of fish populations and disrupt marine ecosystems. Conservation efforts include establishing protected areas, implementing sustainable resource management, and raising awareness about the importance of biodiversity.
Q15: Discuss the concept of 'wildlife conservation.' Explain the role of national parks and wildlife sanctuaries in protecting endangered species. Provide examples of successful wildlife conservation initiatives in India.
Ans: Wildlife conservation is the practice of protecting and preserving wildlife and their habitats. National parks and wildlife sanctuaries play a crucial role by providing safe havens for endangered species. For instance, the Kaziranga National Park in India has been instrumental in the conservation of the one-horned rhinoceros. Successful initiatives in India include Project Tiger, aimed at conserving the Bengal tiger, and Project Elephant, focused on protecting the Asian elephant. These projects involve habitat preservation, anti-poaching measures, and community involvement to ensure the survival of endangered species.
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