HUMAN ACTIVITIES THAT SPEED UP OR TRIGGER LANDSLIDES / EARTH & LIFE SCIENCE / SCIENCE 11 - MELC 17

Tantan HD

28 Oct 202006:03

Summary

TLDRThis video explains how human activities can accelerate or trigger landslides, which can cause significant damage and fatalities. It covers activities like mining, quarrying, land development, land pollution, excavation, and deforestation. The video also highlights ways to prevent or mitigate landslides, such as proper drainage, maintaining vegetation, using slope-friendly building designs, and hazard mapping. Practical measures like dewatering, slope reinforcement, and educating the public about landslide warning signs are also discussed. Viewers are encouraged to be proactive in preventing landslides and minimizing their impact.

Takeaways

🌍 Landslides are triggered by the movement of rocks, debris, or earth down a slope, causing harm to communities.
📚 There are different types of landslides, including falls, topples, slides, spreads, and flows, which have five different categories.
⛏️ Human activities such as mining, which involves using explosives, can trigger landslides by creating mini earthquakes.
🏗️ Quarrying, which involves excavating stone with explosives, can cause vibrations leading to landslides in slopes.
🏡 Land development, particularly altering landscapes for agriculture or housing, makes land more susceptible to landslides during heavy rainfall.
🛠️ Excavation and deforestation are significant contributors to landslides by destabilizing slopes.
💧 Proper drainage systems can help prevent landslides by directing water away from foundations and preventing soil oversaturation.
🌱 Vegetation cover and tree planting on slopes are effective ways to reduce soil erosion and landslide risks.
🏡 Construction on slopes should be adapted to the natural slope to minimize the risk of landslides.
🗺️ Hazard mapping and public education can help locate areas prone to landslides and prepare communities for potential risks.

Q & A

What is a landslide?
-A landslide is the movement of a mass of rock, debris, or earth down a slope that causes harm to the community.
What are the different types of landslides mentioned in the video?
-The types of landslides mentioned are falls, topples, slides, spreads, and flows, which have five different categories.
How can mining activities trigger landslides?
-Mining uses explosives underground, creating mini earthquakes that can cause landslides.
What is the role of quarrying in causing landslides?
-Quarrying involves excavation and blasting, which creates vibrations that can trigger landslides on slopes.
How does land development make areas more susceptible to landslides?
-Land development alters the shape of slopes or imposes new loads, making the land susceptible to soil liquefaction during heavy rainfall.
Why is deforestation a factor in triggering landslides?
-Deforestation removes trees, destabilizing already fragile slopes and making them more prone to landslides.
What are some methods mentioned to prevent landslides?
-Methods include checking drainage systems, maintaining vegetation cover, planting trees on slopes, minimizing irrigation, and adapting building designs to natural slopes.
Why is vegetation important in preventing landslides?
-Vegetation cover helps protect land from landslides and soil erosion, especially on slopes.
What are the signs that may indicate a potential landslide?
-Signs include leaning fences or walls, changes to surroundings, and the oversaturation of soil due to rain or water.
How can hazard mapping help in landslide prevention?
-Hazard mapping identifies areas prone to slope failures, helping in determining safer locations for building settlements.

Outlines

00:00

🌍 Introduction to Human Activities Triggering Landslides

This paragraph introduces the concept of landslides and their link to human activities. It explains how landslides, which involve the downward movement of earth, rock, or debris, can be triggered by various human actions. It also briefly recaps previous lessons on different types of landslides, including falls, topples, slides, spreads, and flows. Mining, quarrying, land development, land pollution, excavation, and deforestation are identified as human activities that can trigger or accelerate landslides.

05:00

🏗️ Human-Induced Landslide Factors and Mitigation Strategies

This paragraph delves into how specific human activities like mining, quarrying, land development, and deforestation contribute to landslides. It explains that mining uses explosives that create vibrations, leading to mini-earthquakes that cause landslides. Similarly, quarrying involves cutting and blasting that also triggers landslides. Land development, which alters the landscape, makes the soil more prone to liquefaction during rainfall. To mitigate landslides, several strategies are suggested, including checking drainage systems, maintaining vegetation, and planting trees on slopes to prevent erosion.

🛠️ Practical Measures to Prevent Landslides

The paragraph continues by offering practical methods to reduce the risk of landslides. It suggests measures like minimizing surface irrigation, ensuring building designs suit natural slopes, enforcing proper land use regulations, and watching for signs of potential landslides (like leaning fences). The importance of keeping waste off slopes and installing impermeable membranes to avoid soil oversaturation is highlighted. Techniques for slope stabilization, such as modifying slope geometry and reinforcing slope material with chemicals, are also discussed.

📊 Hazard Mapping and Public Education on Landslide Prevention

This final paragraph discusses hazard mapping, which helps locate areas prone to landslides and informs where settlements should be built. It also emphasizes the importance of educating the public about signs of impending landslides and safety measures to minimize their impact. The lesson concludes with a congratulatory note to the viewers, signaling the end of the video.

Mindmap

Keywords

💡Landslide

A landslide is the movement of a mass of rock, debris, or earth down a slope, which can cause significant harm to communities. The video highlights how landslides are triggered by both natural factors and human activities, such as mining, quarrying, and deforestation. Examples of landslides include falls, slides, and flows, all of which can lead to fatal consequences, especially in areas where slopes are destabilized.

💡Mining

Mining involves the extraction of minerals and geological materials from the earth, often using explosives that create small earthquakes, which can trigger landslides. This process is directly linked to destabilizing slopes, as the vibrations caused by mining operations can make the ground more susceptible to failure. The video emphasizes mining as one of the primary human activities that speeds up the occurrence of landslides.

💡Quarrying

Quarrying refers to the excavation of stones, slate, or other building materials from an open pit. Similar to mining, it often involves blasting and cutting, which generates vibrations that can lead to landslides, particularly on unstable slopes. Quarrying is discussed as another human activity that contributes to triggering landslides by disturbing the natural structure of the land.

💡Land development

Land development is the process of altering a landscape from its natural state to support activities such as agriculture or housing. This can change the shape of slopes and impose new loads on them, increasing their vulnerability to landslides, especially during heavy rainfall. The video explains how this type of human intervention often makes the land susceptible to soil liquefaction, a phenomenon where the ground loses stability.

💡Deforestation

Deforestation is the removal of trees and forests, which destabilizes slopes by eliminating the root structures that help hold soil in place. Without trees, slopes become more prone to landslides, particularly during rainstorms. The video uses deforestation as an example of how human activities that clear land for farming or infrastructure can unintentionally increase the risk of landslides.

💡Excavation

Excavation involves digging or moving earth, rock, or other materials, often for construction purposes such as building foundations, reservoirs, or roads. This process can weaken slopes, making them more likely to collapse and cause landslides. The video explains how excavation for construction can be a direct contributor to landslide occurrences.

💡Land pollution

Land pollution refers to the degradation of the earth’s surface due to human activities like improper waste disposal, industrial waste, and overexploitation of soil. The video highlights land pollution as a contributing factor to landslides, particularly when it leads to the misuse of soil, which weakens its stability and increases susceptibility to landslides.

💡Soil liquefaction

Soil liquefaction occurs when soil loses its strength and behaves like a liquid, typically triggered by heavy rainfall or seismic activity. It is a critical factor in causing landslides during events like heavy rainfall. The video explains how human activities, such as land development, make slopes more prone to liquefaction, which can lead to sudden and catastrophic landslides.

💡Hazard mapping

Hazard mapping is the process of identifying areas that are prone to natural disasters like landslides. The video emphasizes the importance of hazard mapping in identifying high-risk areas to avoid building settlements there. It is a proactive method to prevent landslides by ensuring proper land use based on scientific data.

💡Slope stabilization

Slope stabilization involves various techniques to prevent landslides by reinforcing slopes, such as modifying slope geometry, planting vegetation, or installing retaining walls. The video discusses how slope stabilization methods, like planting trees or controlling irrigation, can help reduce the likelihood of landslides and mitigate their impacts on communities.

Highlights

Introduction to human activities that speed up or trigger landslides.

Review of previous knowledge: Landslides are the movement of mass like rock debris or earth down a slope causing harm to the community.

Types of landslides mentioned: falls, topples, slides, spreads, and flows with five different categories.

Landslides can cause significant fatalities, often linked to human activities.

Mining as a human activity: Using explosives underground creates mini earthquakes that can trigger landslides.

Quarrying: Explosives cause vibrations that trigger landslides on slopes.

Land development: Changing landscapes for agriculture or housing alters slopes, increasing susceptibility to landslides.

Land pollution: Degradation of land surfaces due to industrial waste, improper soil use, and mineral exploitation.

Excavation: Construction processes that involve moving earth, rock, or other materials with explosives increase landslide risks.

Deforestation: Removing forests destabilizes fragile slopes, increasing the risk of landslides.

Preventing landslides: Ensuring proper drainage systems to direct water away from home foundations.

Vegetation cover helps protect land from landslides and soil erosion.

Planting trees on slopes and slopes' base can prevent erosion.

Use of scientific research for effective land use regulations and building codes.

Hazard mapping helps identify areas prone to slope failures for safe building settlements.