5. How Do Human Activities Affect Coastal Processes?

Human actions have a big impact on coastal processes like erosion, deposition, and the formation of beach features. These actions can disturb the natural balance of coastal environments, causing long-lasting damage. Here are some ways human activities change these processes:

1. Coastal Development

• City Building: When cities, hotels, and resorts are built along coastlines, natural habitats can be destroyed. This increases the chance of erosion. In fact, urban development can raise erosion rates by up to 200% in some sensitive areas.
• Hard Structures: Things like sea walls, groynes, and jetties can protect certain parts of the coast. However, they can cause more erosion in other areas. For example, groynes can reduce sand on nearby beaches by 50%, making those areas erode faster.

2. Dredging and Sand Mining

• Dredging: This is when sand and gravel are taken from the ocean floor. Dredging can change how sand moves naturally and hurt local ecosystems. In some places, dredging has caused a loss of about 1 million cubic meters of sand every year.
• Sand Mining: In some areas, illegal sand mining has made coastlines weaker. Studies show that these places can lose up to 5 meters of beach width every year.

3. Climate Change

• Rising Sea Levels: Ice caps are melting and the ocean is getting warmer, which makes sea levels rise. Since 1901, global sea levels have gone up by around 20 cm. This leads to more flooding and erosion along coastlines.
• Stronger Storms: Climate change caused by humans has made storms more intense and frequent. Research shows that storms today are 30% stronger than they were a few decades ago, which causes more erosion during these events.

4. Agriculture and Land Use Changes

• Cutting Down Trees: When mangroves and coastal forests are removed for farming or development, it makes coastlines more vulnerable to erosion and storm damage. Mangroves can reduce wave energy by up to 75%, protecting coastlines. Losing these trees can increase erosion by up to 50%.
• Farming Runoff: Fertilizers and pesticides from farms can wash into coastal areas, harming water quality. This nutrient pollution can lead to too many algae blooms, which can destroy aquatic life and hurt coastal stability.

5. Tourism and Recreational Activities

• Beach Upkeep: Many places are creating artificial beaches to attract tourists. To keep these beaches nice, they often add sand, which can disrupt the natural movement of sand. Fixing beaches can cost between $1 million and$6 million for each kilometer.
• More Visitors: Activities like walking on dunes and sensitive areas can damage them. This makes it harder for these areas to protect against erosion.

Conclusion

In conclusion, human activities create major changes in natural coastal processes. Building cities, dredging, climate change, farming practices, and tourism all increase erosion and harm important coastal habitats. It’s important to use sustainable practices and policies to reduce these impacts and protect our coastlines for the future.