Human Causes
Large areas of forests near the rivers have been cleared. The lands use to make rooms for settlements, roads and farmlands. Less vegetation protect the soil, the soil is quickly lost to rivers and sea. This raises the riverbed, so the river overflows its banks easily.
One of the deforested areas near Chang Jian
Source: Living Geography 2A
How deforestation leads to flooding:
- No trees to soak up water, so more water flows into the rivers.
- No trees to bind the soil together, so soil erosion takes place. Large amounts of soil are washed by rain into the rivers.
- Because of silting,
riverbed shallower. The water volume increases, the river cannot hold
all the water and overflows its banks.