Audio Notes: अपक्षय, जन आंदोलन और भूजल Video Lecture | यूपीएससी सीएसई के लिए भूगोल (Geography) - UPSC

Ans. Weathering is the process of breaking down rocks and minerals at the Earth's surface through physical, chemical, and biological means. The main types include: 1. <b>Physical Weathering</b>: This involves the mechanical breakdown of rocks without changing their chemical composition. Common processes include freeze-thaw cycles and thermal expansion. 2. <b>Chemical Weathering</b>: This process alters the chemical structure of minerals, often involving reactions with water, acids, or gases. Examples include hydrolysis, oxidation, and carbonation. 3. <b>Biological Weathering</b>: This occurs when living organisms, such as plants and microorganisms, contribute to the breakdown of rocks through biological processes.

Ans. Mass movement refers to the downward movement of soil and rock due to gravity. It significantly impacts the landscape by: 1. <b>Erosion</b>: It can lead to the erosion of hillsides and cliffs, reshaping the landscape and creating features such as landslides and gullies. 2. <b>Deposition</b>: Materials moved by mass movement can accumulate in new locations, forming features like alluvial fans and deltas. 3. <b>Alteration of Ecosystems</b>: Mass movements can disrupt habitats, change drainage patterns, and affect vegetation, leading to long-term ecological changes.

Ans. Groundwater plays a critical role in the weathering process by: 1. <b>Chemical Reactions</b>: Groundwater can dissolve minerals through chemical weathering, particularly in limestone and other soluble rocks, leading to features like caves and sinkholes. 2. <b>Transport of Sediments</b>: It helps transport dissolved materials and sediments, contributing to soil formation and nutrient cycling. 3. <b>Influencing Erosion</b>: Groundwater can affect the stability of slopes and cliffs, influencing mass movement events like landslides when soil becomes saturated.

Ans. Mass movement events can have several environmental impacts, including: 1. <b>Loss of Vegetation</b>: Landslides and other forms of mass movement can remove vegetation, which can lead to soil erosion and loss of habitat for wildlife. 2. <b>Water Quality Degradation</b>: Erosion caused by mass movement can lead to sedimentation in waterways, impacting water quality and aquatic ecosystems. 3. <b>Infrastructure Damage</b>: Mass movements can damage roads, buildings, and other infrastructure, leading to economic repercussions and safety hazards for communities.

Ans. Human activities can significantly influence weathering and mass movement through: 1. <b>Deforestation</b>: Removing vegetation increases soil erosion and destabilizes slopes, leading to greater susceptibility to mass movement. 2. <b>Construction Activities</b>: Excavation and grading for buildings and roads can change drainage patterns and increase runoff, enhancing erosion and mass movement risks. 3. <b>Mining and Quarrying</b>: These activities can lead to significant alterations in the landscape, increasing the likelihood of landslides and other forms of mass movement due to destabilization of soil and rock.