Biogeography & Ecosystems

Fern: * Ferns typically require soil and moisture to grow, as they rely on water-conducting tissues and need a substrate to anchor their roots. Lichen:
* Lichens are a symbiotic association between a fungus and an algae or cyanobacteria. * Lichens are well-adapted to survive on surfaces without soil, such as rocks, tree bark, and even bare ground, as they can obtain their nutrients and moisture directly from the air and precipitation. * Lichens are sensitive to airborne pollutants, such as sulfur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), and heavy metals (like lead and mercury).
Sulfur dioxide, for instance, causes chlorosis (yellowing) and necrosis (cell death) in lichen thalli. This sensitivity makes lichens an effective indicator of air quality. Moss:
* Mosses are non-vascular plants that can grow on surfaces without soil, such as rocks, tree trunks, and even roofs. * Mosses have specialised structures that allow them to absorb water and nutrients directly from the environment. Mushrooms:
* Mushrooms are the reproductive structures of fungi, and they typically require a substrate, such as decaying organic matter, to grow. Mushrooms are not able to directly survive on a surface without soil or a nutrient-rich medium. Therefore, among the given options, lichens and mosses are the most likely to be found surviving on a surface without soil in the natural environment.

Biochar is a solid product obtained during the pyrolysis of biomass. It is a porous, carbon-rich material that has a wide range of uses, with soil improvement, remediation, and pollution control playing the most significant roles. In agriculture, biochar is primarily used to increase crop nutrition, plant growth, and soil fertility. Statement 1 is correct. Biochar can indeed be used as a part of the growing medium in vertical farming. It helps in improving the soil structure and fertility, thereby promoting plant growth. Statement 2 is correct. Biochar promotes the growth of nitrogen-fixing microorganisms. These microorganisms play a crucial role in the nitrogen cycle by converting atmospheric nitrogen into a form that plants can use. Statement 3 is correct. Biochar also enables the growing medium to retain water for a longer time. Its porous nature allows it to hold onto water and nutrients, making them readily available for plant roots. Therefore, all three statements are correct.

Eco-friendly agriculture refers to farming practices that are sustainable and cause minimal harm to the environment. Crop diversification is one such practice. It involves growing a variety of crops in the same area over different seasons. This method enhances soil health, reduces the need for excessive water and fertilizers, and boosts biodiversity in the ecosystem. By rotating crops, it also helps in preventing soil depletion and improves resilience against pests and diseases. Legume intensification is another eco-friendly practice. Legumes are known to improve soil fertility by fixing nitrogen from the atmosphere. This reduces the need for synthetic fertilizers, making agriculture more sustainable. Tensiometer is a useful tool in efficient water management. It measures the water tension in soil, which helps in determining the availability of water for crops. By ensuring that water is used efficiently, it reduces waste and promotes sustainable water usage, making it an eco-friendly farming practice. Vertical farming involves growing crops in vertically stacked layers, often using advanced techniques like hydroponics, aeroponics, and aquaponics, which do not require soil. While this method can increase production and reduce land usage, it requires high energy consumption and specialized technology. Hence, it is not widely considered as an eco-friendly practice. Therefore, the correct answer is A. 1, 2, and 3 only.

Statement 1 is correct: Desert National Park is located in Rajasthan and is one of the largest national parks in India, covering an area of around 3,162 km². It represents the Thar Desert ecosystem, featuring sand dunes, rocky terrain, and sparse vegetation. The park is spread across Jaisalmer and Barmer districts of Rajasthan. Statement 2 is incorrect: Unlike some protected areas, human settlements exist within Desert National Park. Several villages and communities, including those engaged in livestock rearing, are located inside the park. Statement 3 is correct: The park is one of the last strongholds of the Great Indian Bustard (Ardeotis nigriceps), which is critically endangered. Conservation efforts, including captive breeding programs, are ongoing to protect this bird.
Therefore, the correct answer is that statements 1 and 3 are correct.

The Agasthyamala Biosphere Reserve is a vital ecological hotspot located in the Western Ghats of southern India. It serves as a unique genetic reservoir of cultivated and wild plant species, including many rare, endemic, and medicinal plants. The biosphere reserve spans across Kerala and Tamil Nadu, covering diverse ecosystems from tropical forests to montane grasslands. It includes three wildlife sanctuaries Shendurney (Kerala), Peppara (Kerala) and Neyyar (Kerala), as well as the Kalakad Mundanthurai Tiger Reserve (Tamil Nadu).

Statement 1 is correct: Global warming poses a significant threat to methane hydrate deposits. These icy structures, found in permafrost and deep-sea sediments, can destabilize as temperatures rise, releasing methane into the atmosphere. Since methane is a potent greenhouse gas its release could create a positive feedback loop, further accelerating global warming. Statement 2 is correct: Large deposits of methane hydrate are primarily found in two locations:
1. Arctic Tundra: Permafrost soils in the Arctic hold significant methane hydrate reserves, which are at risk of melting due to rising temperatures.
2. Seafloor Deposits: Continental margins and deep ocean sediments contain vast methane hydrate reserves. Changes in ocean temperature and pressure fluctuations can trigger their release. Statement 3 is correct: After about 12 years, the methane is converted into carbon dioxide through hydroxyl oxidation. While CO₂ is a less potent greenhouse gas than methane, its longer atmospheric lifetime means it continues contributing to long-term climate change. Therefore, option (D) 1, 2 and 3 is correct.

Manas National Park (Assam): Situated on the banks of the Manas River, it encompasses a range of ecosystems including grasslands, tropical evergreen forests, and semi-evergreen forests. Namdapha National Park (Arunachal Pradesh): This park boasts diverse vegetation zones, ranging from tropical evergreen forests at lower elevations to sub-alpine meadows at higher altitudes. Neora Valley National Park (West Bengal): This park covers a range of elevations with subtropical broadleaf forests at lower levels and temperate forests at higher reaches. The Valley of Flowers National Park (Uttarakhand): On the other hand, is situated at a high altitude (3352 to 3658 metres above sea level) and falls entirely within the temperate alpine zone, known for its meadows, low-growing vegetation, and cooler climate. Hence, option D is the correct Answer.

The correct ascending order for the percentage of forest cover in the mentioned states 1. Odisha (32.34%)
2. Madhya Pradesh (25.11%)
3. Maharashtra (16.47%)
4. Chhattisgarh (41.09%) Chhattisgarh has the highest forest cover percentage, followed by Odisha, Madhya Pradesh, and Maharashtra. Hence the correct answer is option 3, i.e 3-2-4-1. (Ascending order)

Remote sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance from the targeted area. Statement 1 is correct. Satellite images and remote sensing data can indeed be used to estimate the chlorophyll content in vegetation. This is done by measuring the reflectance of light from the vegetation. The chlorophyll in plants absorbs light for photosynthesis, and the amount of light reflected back can give an estimate of the chlorophyll content. Statement 2 is correct. Satellite images and remote sensing data can also be used to estimate greenhouse gas emissions. This is done by detecting the radiations emitted by the substances in the rice paddies. Statement 3 is correct. Satellite images and remote sensing data can be used to measure land surface temperatures as well. This is done by detecting the infrared radiation emitted by the land surface. Therefore, all three parameters can be measured or estimated using satellite images or remote sensing data.

Plants in arid environments have evolved adaptive features to minimize water loss through transpiration: - Hard and waxy leaves have a thick cuticle and fewer stomata, reducing water loss by limiting evaporation.
- Tiny leaves have a smaller surface area, which decreases the area exposed to transpiration.
- Thorns, though primarily modified branches for protection, can also replace leaves in some desert plants (e.g., cacti), further reducing transpiration by limiting leaf surface area. Therefore, the correct answer is option (d) 1, 2 and 3.