Ans: C

Exp:

Pair 1 is correct: Laterite soil, recognized by its reddish hue, is a coarse-textured soil rich in iron and aluminum oxides. It’s commonly found in tropical regions and often has acidic properties due to leaching. Although laterite soil is quite infertile for agriculture due to its acidity and limited nutrient availability, it can be used for crops like cassava, rubber, oil palm etc.

Pair 2 is correct: Podzol soils (grey colour) found in temperate coniferous areas are characterised by their acidity and mineral deficiency, primarily due to significant water movement through the soil with limited upward evaporation. This leaching process often washes away essential soluble nutrients such as calcium, nitrogen, and potassium, as well as iron and aluminium.

Pair 3 is correct: The soil in the desert is coarse grained. They are coarse because there is less chemical weathering. The finer dust and sand particles are blown elsewhere, leaving heavier pieces behind. Canopy in most deserts are very rare. Plants are mainly ground-hugging shrubs and short woody trees.

Ans: A

Exp

Rainforests and equatorial forest ecosystems are often called the “lungs of the Earth” because they produce a significant amount of oxygen through photosynthesis while also absorbing carbon dioxide, contributing to climate regulation. These biodiverse regions play a critical role in maintaining global oxygen levels, regulating the climate, and supporting countless species of plants and animals. Protecting these ecosystems is crucial for the planet’s health and the well-being of all living organisms.

Ans: B

Exp:

Statement 1 is incorrect: Succession is a process that starts in an area where no living organisms are there. These could be areas where no living organisms ever existed, say bare rock; or in areas that somehow, lost all the living organisms that existed there. The former is called primary succession, while the latter is termed secondary succession.

Statement 2 is correct: Based on the nature of the habitat, whether it is water (or very wet areas) or it is on very dry areas – succession of plants is called hydrarch or xerarch, respectively. Hydrarch succession takes place in wet areas and the successional series progresses from hydric to the mesic conditions. As against this, xerarch succession takes place in dry areas and the series progresses from xeric to mesic conditions. 

Statement 3 is correct: Both hydrarch and xerarch succession lead to medium water conditions (mesic) i.e. neither too dry (xeric) nor too wet (hydric). 

Ans: A

Exp:

Option 1 is correct: Forests are a classic example of a terrestrial ecosystem. They are characterized by a variety of trees, plants, animals, and microorganisms interacting in a specific geographical area. Examples of forest systems are Tropical Rain Forests, Savanna, Tropical Deciduous, taiga, etc.  

Option 2 is correct: Grasslands are also terrestrial ecosystems characterized by vast expanses of grasses with varying degrees of tree cover. The grassland biome is found where rainfall is about 25-75 cm per year, not enough to support a forest but more than that of a true desert. Typical grasslands are 

vegetation formations that are generally found in temperate climates.

Option 3 is incorrect: An ash pond, typically associated with power plants, is not a natural terrestrial ecosystem. It is a human-made structure used for storing ash generated from the combustion of coal. As such, it does not occur naturally and is not a type of terrestrial ecosystem. It is classified as a man-made wetland.

Option 4 is incorrect: Mangroves are coastal ecosystems that exist at the interface between land and sea. Mangroves are salt-tolerant (halophytes) evergreen shrubs or small trees (vary in height from 8 to 20 m) that represent a characteristic littoral (near the seashore) forest ecosystem. They grow below the high water level of spring tides. The best locations are where abundant silt is brought down by rivers or on the backshore of accreting sandy beaches.

Option 5 is correct: Deserts are terrestrial ecosystems characterized by arid conditions, low precipitation, and specific adaptations of plants and animals to survive in harsh environments. Deserts are formed in regions with less than 25 cm of annual rainfall, or sometimes in hot regions where there is more rainfall but it is unevenly distributed in the annual cycle. Lack of rain in the mid-latitude is often due to stable high-pressure zones; deserts in temperate regions often lie in “rain shadows.” Some examples of deserts are the Sahara desert, Atacama desert, Gobi desert, etc.

Ans: C

Exp:

Statement 1 is not correct: The littoral zone is the shallow water zone of the lake which supports rooted vegetation. The littoral zone is the near-shore area where sunlight penetrates all the way to the sediment and allows aquatic plants (macrophytes) to grow. Light levels of about 1% or less of surface values usually define this depth.

Statement 2 is not correct: Limnetic zone is the ideal location for the growth of phytoplanktons. The profundal zone is the zone which does not receive any light. 

Statement 3 is correct: The benthic zone is the deepest layer among all the zones of lakes/water bodies, they are a habitat for benthic organisms like snails etc.