Bananas growing near a stream. Image credit MediaWiki.

Bananas growing near a stream. Image credit MediaWiki.

ZIMSEC O Level Geography Notes: River Processes: Stream bank cultivation

  • Stream bank cultivation refers to the practice of growing or cultivation of crops near a wetland, stream or river.
  • Sub-Saharan Africa has faced political, socio-economic problems in the recent times.
  • These┬áproblems have been in brought about┬áby erratic rainfall patterns in the region.
  • In Zimbabwe, erratic rainfall patterns, lack of employment and poverty has led to the cultivation of stream banks.
  • An example of areas that experience a lot of streambank cultivation are the peri-urban areas of Seke-Chitungwiza.
  • Crops are grown mostly for domestic consumption although horticultural activities such as vegetable grown is sometimes carried out with most of the produce sold at local farmer’s markets.

Results

  • Stream bank cultivation results in siltation and the choking of rivers and dams.
  • It also leads to eutrophication as fertilizers containing nitrates are washed into the rivers.
  • It also leads to the disturbance of natural ecosystems.

Gold Panning

Korokoza's panning for gold. Image credit Bulawayo24.com

Korokoza’s panning for gold. Image credit Bulawayo24.com

Results

  • It results in the siltation and choking of rivers and dams.
  • It leads to pollution as dangerous chemicals like mercury an cyanide are released into streams.
  • The disturbances of ecosystems.

Urbanization

Urbanisation leads to increased overland flow. Image credit zimbojam.com

Urbanisation leads to increased overland flow. Image credit zimbojam.com

Results

  • Results in increased pollution and disturbances of ecosystems.
  • Increased impervious surfaces result in increased overland flow, shorter lag time between a storm and a surge in discharge and increased incidences of flooding downstream.

River diversions

Water Canal. Image credit  texasbeyondhistory.net

Water Canal. Image credit texasbeyondhistory.net

  • Sometimes river water is diverted through man made canals, dames and pipelines to supply water for irrigation, industrial and domestic use.
  • The Pungwe Project in Mutare is an example.
  • The result is decreased discharge and the formation of more deposition features.
  • This may also lead to the shortage of water downstream.

 


Quick NetOne, Telecel, Africom, And Econet Airtime Recharge

If anything goes wrong, chat with us using the chat feature at the bottom right of this screen