How Farmers Can Prepare for and Handle Landslides
Landslides are fairly unique among natural disasters because people can help prevent them. Hurricanes, tornadoes and droughts may be inevitable, but protective measures can mitigate landslide risks.
Why Landslides Have Become More Common
Landslides mainly occur in hilly areas and are often triggered by an earthquake or flash flood. For example, landslides affect more than 20 percent of the hill slopes in the city of Bujumbura, which is situated in the landslide-prone East African Rift. Across Africa and the Middle East, climate change is contributing to landslides. Overall rainfall is down in many areas, but the intensity of storms has increased, leading to worse erosion.
Human factors are also creating more severe landslides. Deforestation, building roads without adequate grading of slopes and altering drainage patterns can all contribute to landslides.
In addition, population growth is worsening the effects of landslides. Scientists predict the population will reach almost 10 billion by 2050, and as people push farther into rural areas and build new developments, they become more vulnerable to natural disasters. Building on slopes also means the soil under houses is more prone to erosion.
How Farmers Can Help Prevent Landslides
Farmers should avoid building their houses and outbuildings near slopes, drainage ways, erosion valleys or mountain edges. If establishing a farm near any of these geographic features, building a retaining wall, deflection wall or channels to divert the flow of water and mud can help reduce landslide risks. Farmers can hire geohazard monitoring teams to assess an area for landslide risks using light detection and ranging (LIDAR), Interferometric Synthetic Aperture Radar (InSAR), in-ground measurements and aerial photographs.
Several other human-made interventions help prevent landslides. Rock bolts can stabilize coherent masses, although this works best in areas with rock fractures or joints that need to stay together. Using pipes to drain water from slopes makes them a lot more stable. It’s important to ensure drainage systems, downspouts and gutters direct water away from hills.
Farmers should avoid removing roots, stumps, trees and ground cover from slopes. Revegetating bare soil with plants can stabilize potential failure planes, because plants with deep root systems help hold the ground in place. Bamboo makes an excellent reinforcement material to stabilize the soil in a sustainable manner, and farmers can also sell excess bamboo or use it as a building material.
Terracing redistributes mass along a slope and reduces the slope’s angle. Farmers can practice terrace farming to potentially reduce landslides, conserve water and improve soil conservation.
Becoming Landslide Ready
Farmers should learn to recognize common landslide warning signs, including:
- Bulging of the ground at the base of a slope;
- Walls, stairs or walkways pulling away from a building;
- Utility lines breaking underground;
- The sound of trees snapping or boulders bumping together;
- Pavement collapsing;
- Water seeping through the ground in new locations;
- Doors or windows becoming jammed for the first time; and
- Changes in the landscape, such as ground movement or leaning trees.
Additionally, farmers can take steps to prepare themselves for a possible landslide. It’s wise to build an emergency kit that includes food, medicine, shelter and navigation equipment. Farmers should also ensure their animals are clearly identifiable in case they get loose — brands, ear tags, collars and microchips can help identify loose livestock.
Families should make plans for their entire household to evacuate in case of a landslide. They should also sign up for community warning systems and identify which shelter they will use during a natural disaster.
Living Alongside Landslides
Many regions of Africa and the Middle East are prone to landslides. Farmers must pay close attention to the geography of their farms and do their best to minimize deforestation, overgrazing and other problems that could lead to erosion. They should also use deep-rooted plants and man-made structures to help hold the soil in place. Landslides are a part of life, but people can minimize their impact by taking preventative measures.