80 RAS Prelims MCQs on natural vegetation and biomes ask about the forest types of the world, their layers, trees and soils. The Amazon rainforest, temperate rainforests, the boreal forest, the temperate deciduous forest and the Great Barrier Reef are tested, and each explanation links the biome to its climate and location.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 71–80 of 80 questions
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q71. The following question consists of two statements--Statement I and Statement II. Answer the question by selecting the appropriate option. Statement I: The sequence of biomes observed when traveling from the equator to the poles is broadly mirrored when ascending a tall mountain in the tropics. Statement II: This occurs because increasing altitude results in temperature and precipitation changes similar to those caused by increasing latitude.
Explanation
The distribution of biomes on mountains mirrors their distribution across latitudes. As altitude increases, temperatures drop and environmental conditions change, similar to moving toward the poles. Consequently, a traveler ascending a tropical mountain may pass through rainforests, deciduous forests, coniferous forests, and finally reach alpine tundra at the peak. This vertical zonation is a fundamental concept in biogeography and ecology.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q72. While defining biomes, the terms ecosystem and biome are related but distinct. Which of the following best highlights the relationship?
Explanation
Biomes and ecosystems are related but differ in scale. A biome is a large geographic area defined primarily by its climate and dominant vegetation types. Within a single biome, there can be many different ecosystems, which are smaller units where living organisms interact with each other and their specific physical environment. Thus, a biome serves as a broader category for similar ecosystems.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q73. Which of the following statements explains why laterite soils, typical of tropical rainforests, are generally unsuitable for sustained agricultural use post-deforestation?
Explanation
Laterite soils in tropical rainforests are often poor for agriculture because high rainfall leaches away essential nutrients and silica. This leaves behind a soil rich in iron and aluminum oxides, which can harden into a brick-like substance when exposed to the sun after deforestation. This lack of nutrients and poor physical structure make it difficult to sustain crops without heavy fertilization.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q74. Forests dominated by commercially valuable species like Teak and Sal are the hallmark of which biogeographical zone in India?
Explanation
Tropical deciduous forests are the most widespread forest type in India. They are characterized by trees like teak and sal, which are highly valued for their durable hardwood. These forests are adapted to the seasonal monsoon climate, shedding their leaves during the dry months. They play a significant role in the country’s economy and provide critical habitat for diverse wildlife species.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q75. Which of the following statements regarding the climate of the Tropical Savanna biome is incorrect?
Explanation
The tropical savanna biome is located in transitional zones between rainforests and deserts. It is characterized by a distinct dry season and a wet season. However, the annual rainfall in a savanna is significantly lower and less evenly distributed than in the tropical rainforest. This limited and seasonal water availability is what prevents the growth of dense forests and favors expansive grasslands.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q76. The Mediterranean biome is globally renowned for a specific type of agriculture centered around the cultivation of grapes for wine production. This practice is formally known as:
Explanation
Viticulture is the specialized agricultural practice of cultivating grapes, particularly for wine production. This is a hallmark of Mediterranean agriculture, thriving in the region’s climate of mild, wet winters and hot, dry summers. Other typical crops in these regions include olives, citrus fruits, and figs. The unique climatic conditions provide the perfect environment for these drought-resistant and sun-loving plant species.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q77. The Temperate Grasslands are often referred to as the "granaries of the world." What ecological characteristic of this biome makes it most suitable for extensive cereal cultivation?
Explanation
Temperate grasslands, like the North American prairies and Eurasian steppes, are ideal for cereal cultivation due to their highly fertile Mollisol soils. These soils are deep and rich in organic matter. Additionally, the flat or gently rolling topography of these regions facilitates large-scale, mechanized farming. The combination of soil quality and suitable terrain makes them the primary grain-producing regions of the world.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q78. What is the primary cause of the high acidity of soils found in the Boreal Forest (Taiga) biome?
Explanation
The soils of the boreal forest, known as podzols, are highly acidic primarily due to the nature of the vegetation. Conifer needles are rich in acidic compounds and decompose very slowly in the cold climate. As they break down, they release organic acids that leach through the soil, removing basic minerals and leaving behind an acidic, nutrient-poor, and often ash-grey horizon.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q79. Which of the following deserts is correctly paired with the continent it is located on?
Explanation
Deserts are found across all continents, each with unique characteristics. The Mojave Desert is a prominent arid region located in the Southwestern United States in North America. Other examples include the Atacama in South America, the Sahara and Kalahari in Africa, and the Great Victoria Desert in Australia. Each desert’s location is determined by factors like atmospheric circulation and rain shadow effects.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q80. While coral reefs face numerous localized threats such as overfishing and pollution, what is currently recognized as the most severe, widespread threat to global coral reef survival?
Explanation
While localized issues like pollution and overfishing are significant, climate change represents the most widespread threat to coral reefs. Rising ocean temperatures lead to frequent and severe coral bleaching events. Furthermore, increased carbon dioxide absorption causes ocean acidification, which hinders the ability of corals to build their calcium carbonate skeletons. These global factors pose an existential threat to reef ecosystems worldwide.
Answer key for these questions
Q
Correct answer
71
(a) Both Statement I and Statement II are correct
72
(a) A biome is a large area with multiple similar ecosystems defined by climate
73
(c) Heavy rainfall leaches nutrients, leaving aluminum and iron oxides
74
(a) Tropical Deciduous Forests
75
(d) Savanna rainfall is higher and more distributed than in the rainforest biome
76
(b) Viticulture
77
(c) Nutrient-rich soils and flat topography suitable for mechanized farming
78
(d) Conifer needles releasing acidic compounds during slow decomposition
79
(a) Mojave Desert : North America
80
(b) Climate change, ocean warming, and acidification
Key facts from Natural Vegetation and Biomes
The dense, broad-leaved evergreen forest of the Amazon Basin is called Selvas.
The layers of a tropical rainforest from the top are emergent layer, canopy, understory and forest floor; epiphytes grow on other plants for support without being parasites.
Podzolization is the soil process most dominant in the Boreal Forest (Taiga).
Boreal forests have extensive pure stands of a single species, which simplifies commercial lumbering.
Temperate deciduous forests are found in eastern United States, western Europe and eastern China.
The Coastal Redwood is a famous tree of the Pacific coast temperate rainforest; the Great Barrier Reef lies off the north-east coast of Australia.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Natural Vegetation and Biomes?
This page has 80 practice MCQs on Natural Vegetation and Biomes (World Geography). Each has the correct answer, and most have an explanation.
What are Selvas?
The local name for the dense, broad-leaved evergreen forest of the Amazon Basin. The high rainfall and heat all year round produce a tall forest with several layers, which makes it the richest rainforest on the planet.
What are epiphytes?
Plants that grow on other plants, mostly trees, for physical support, without being parasites. In tropical rainforests orchids and ferns are epiphytes, and they get light by growing high on tree trunks and branches.
Where is podzolization most common?
In the Boreal Forest, or Taiga, biome. The cold, wet climate and acidic needle litter wash minerals out of the upper soil, producing the grey, infertile podzol soils typical of coniferous forests.
