Wetlands are very important  as they provide a number of things including water. There are a number of impacts that disturb wetlands, we shall look at some of the disturbances.

Types of Impact

  1. Direct Impact

    These are disturbances that happen inside the wetlands. These include filling, grading, removal of vegetation, building construction and changes in water levels and drainage patterns.

  2. Indirect Impact

    These are disturbances that result from things that happen outside wetlands. These include disturbances that happen in uplands, other wetlands or waterways. The disturbances are often caused by disintegration of a wetland from an adjoining wetland complex,  influx of surface water and sediments, loss of recharge area, or changes in local drainage patterns.

  3. Cumulative impacts

    Cumulative impacts happen as a result of a combination of direct and indirect impacts. These impacts happen over time.

 Human Impacts

There are a lot of human effects that have caused substantial changes in the function and quality of a number of wetlands. The changes came from adjustment of the chemical, physical and biological components of wetland ecosystems.  Disturbances caused by humans have affected wetlands in a massive way, land development and clearing have caused increased erosion in the uplands and this has led to amplified sedimentation  wetlands that are in lowlands.

There are a lot of activities that humans are doing that disturb wetlands an0d these activities have a long lasting effect on wetlands.

Dam construction,  Stream channelization, discharge of industrial wastes and municipal sewage and runoff urban and agricultural areas  are dome of the things that humans do that affect wetlands.  These things add to changes in the flood administration of wetlands.

There are irreversible impacts that can happen due to human disturbances. These include agriculture and filling for industrial or residential development.  This is why governments around the world have been trying to protect wetlands. 

Natural Impacts

Sea-Level Rise

Natural sea level rise can also affect wetlands. Because wetlands  are typically within a few feet of sea level, they are affected by the rising sea level. If the sea level rises, the outer boundary of  wetlands will erode, and as a result,  new wetlands will form inland. Areas that were previously dry are flooded by the higher water levels, this is how new wetlands are formed.  The size of the new wetlands that are formed will however be smaller than those that were destroyed. 

Development of a Marsh as The Sea Level Rises

The dry lands that exist now are either forests, urban developed areas or farms. They also are important areas that sustain some local economies.  If all this land becomes wetlands, then this means livelihoods will be affected. Some of the vulnerable places are islands and these islands have recreational areas such as beaches.

Storm and Flood Events

Climate change also affects wetlands.  If the sea level rises, the flood level from a storm also rises. A 3-foot rise in sea level would  cause a 15-year storm to flood many areas that are only flooded by a 100-year storm