Monday, April 23, 2007

What's all the fuss?


Wetlands are marshy swampy areas that may seem like a waste of space, but in fact they are vitally important wild habitats that successfully sustain and maintain various ecosystems in & around them. They even directly benefit us humans too... The destruction of these vital areas will only lead to massive problems- pollution, erosion, flooding, loss of income, and most importantly- enormous loss of essential wildlife. Unfortunately they are disappearing all over the world at an alarming rate- and yet not enough is being done to protect the earths most treasured regions.

Sunday, April 22, 2007

WHAT ARE WETLANDS?

Wetlands are basically the in-between zone that links land & water. A wetland is a damp area where water lies on the surface forming either lakes or pools & where plants have grown up out of the open water. Another way of explaining it is when low-lying land meets water or when a river meets an ocean. No two wetlands are alike, some are wet the whole year whilst others are for only a part of it, you get inland wetlands & coastal wetlands & even man-made wetlands (marshes developing around the edges of reservoirs).
Evidently different types of plants & animals will inhabit different wetlands. Some of the many kinds of wetlands are:
*Swamps- found by coasts of tropical seas
*Bogs- found in cold areas like Great Britain
*Deltas- found at mouth of rivers
*Marshes- formed along rivers or in water-filled depressions
Contrary to popular belief of them being wastelands & a waste of space they all have the same life-saving effect- to animals, plants, various ecosystems, & humans.

Below is a picture of a bog:


WHY ARE WETLANDS IMPORTANT?

It’s a Home
Wetlands support huge numbers of plants & animals. Did you realise that two-thirds of the fish caught in the world began their life in a wetland? So most importantly they provide a home & rich food sources for the enormous number of species they support. They also provide a much needed stop over for migrating birds…without wetlands these species are without a home and eventually perish.

Calms Nature and Recharges Groundwater Supply
Not only do they provide a “buffer zone” or natural barrier during violent storms, an example of this is the mangrove swamps that protect the coastline during storms & reduce damage made, but they also are extremely important during floods. During heavy rains the excess water that is accumulated in the river/stream gets stored in the wetland until the water in the waterway subsides & then slowly the water gets released back into the waterway. This system of control ensures that no water is wasted, erosion doesn’t take place, & no unnecessary damage is caused (flooding damage).

Traps Sediments
Millions of tons of precious topsoil are washed away each year- needlessly lost to the bottom of the ocean. Wetlands stop this by trapping the fine soil particles & instead keeping the rich fertile soil. This also aids in curbing soil erosion.

Nature’s Filters
Wetlands are extremely important as they help to purify the dirty water we are responsible for. They cause the water to flow slowly, which in turn causes sediments & pollutants to sink to the bottom where they can be filtered through the mud & then usually be absorbed & included back into the nutrient system (unless the pollutant load is to much). This is even more important in some areas because the wetlands ensure that the water supply for local cities is good enough to drink.

Direct value to humans
Plants found in wetlands can be made into fertilizer, clothing, building & methane gas. Grazing is also very rich around wetlands. Besides providing animals with food they provide humans as well- rice from marshes, cranberries & blueberries from bogs & seafood from estuaries. They provide recreation & education through hunting, fishing, canoeing, bird watching & studying habitats, all of which provide local communities with an income from lodging & travel. Therefore one can say that the hold great economic value to humans.Below is the example of a rice paddy.


WHAT’S THE PROBLEM THEN?

Recently, humans have been destroying nature’s most valuable asset at an alarming rate. It’s been estimated that half of the world’s wetlands have been destroyed- with loads more under threat.
Did you know? America has lost 54% of its wetlands
France- 67%
SOUTH AFRICA- 50%
Unfortunately we have seen their demise through man’s ignorance & “NOW” attitude.

* Wetlands are being modified or reclaimed
*Resources are being over-exploited
*Upstream development alters the quality & flow of the feeder river therefore negatively altering the wetland
*Dredging
*Canalisation- transport of water to where it’s needed
*Creating new land for agriculture, urban areas & industry (through draining)
*Eliminate shallow depressions that increase water-related diseases

Basically the draining of wetlands for these various reasons means that we are ultimately shooting ourselves in the foot & we actually can’t afford to do so because our futures & those of the various ecosystems are at stake.

Consequences of our thoughtless actions...
Loss of wetlands are disastrous & essentially everything they had a role in playing is impaired.

* The ability to absorb floodwater is greatly reduced so next time there’s an extreme event there will be more serious flooding, possible loss of life & destruction of infrastructure. (Reports have said that the disastrous effects from the 2003 tsunami would have been greatly reduced if the original wetlands were still there.)
* There’ll be a decline in seafood harvests & other products harvested from wetlands.
* Bank erosion will occur
* Larger risk of invasion by alien species
* Migration of birds disrupted
* An extreme situation will be the extinction of some species, & the endangerment of many others
* Wetlands role in filtering water is weakened so over time the river systems becomes degraded
* Because of poor water quality & changed flowing courses, downstream the marine life & ecosystems around them are negatively impacted.

Some of the causes of destruction of wetlands

What a wetland looks like after it's been totally drained


OKAVANGO DELTA ECOSYSYTEM
Botswana is a vast dry country where in the middle of the Kalahari is a
beautiful oasis- the Okavango Delta. This is the home to an immense number & variety of animals, some already critically endangered. This is the world’s largest inland delta. Unfortunately this amazing area is under serious threat. Already cattle ranches have taken parts of the Okavango through draining (destroying whole ecosystems altogether), but still it has been left relatively untouched. Until now. It’s priceless water source, the feeder Kavango River, is under the threat of having its natural flow diverted to Namibia for agricultural & residential use. Despite objections from Botswana, they still plan to go ahead.
At the present moment Botswana’s ecosystem is still intact. (An ecosystem is the relationships between living resources, plants & animals of a particular area.)


But without it’s
major water supply- the essential element for all life to live & survive will disappear and the Okavango’s future will be very bleak.
Without enough water, a large ecosystem cannot be sustained successfully because the plants that don’t receive water will dry out because they don’t have enough nutrients, therefore the area shrinks in size, the plants & trees start to die, the animals & insects die out because they have no food & a whole ecosystem will ultimately perish, and Botswana’s tourism takes a huge beating. As you can see it has a ripple effect. An example of this ripple effect is in Zambia where two dams were constructed on the Kafue River.The result on the surrounding ecosytems was that two species or buck became endangered & the Kobus leche roertsi buck species became extinct.
THIS SIMPLY CAN’T HAPPEN AGAIN.

WE NEED TO TAKE ACTION!
Unless we do something NOW our earth’s most treasured possession could disappear before our eyes.

* National & Local Governments need to be encouraged to start initiatives to protect our remaining wetlands & improve & maintain the quality of those already protected
* We as a united body can support wetland initiatives- visit local parks (in Durban North there’s the Mangrove Swamps), this sends a positive message for wetlands.
* Use less water! This helps keep rivers & lakes full & reduce strain on wetlands.
* Educate anyone who knows not of this plight.
* If you suspect illegal dumping- REPORT IT!
* Don’t use pesticides, herbicides, and harmful chemicals.
* Don’t support people who sell coral, shells etc… because if there’s no demand they won’t exploit the wetlands.
* If you are in charge of an area with a wetland get rid of alien plants & re-introduce indigenous plants. You can also fence areas to protect wildlife from unwanted guests (feral cats, dogs, and humans).
* And if you really have the power-MAKE A RESERVE!

Summary
As you can clearly see wetlands are probably the most important environment we could ever choose to save- the vital impact it has on our lives is beyond comparison & unless we start to take huge steps to stop this worldwide phenomenon the blood will only be on our hands.

Bibliography

* The World Book Encyclopedia, Volume 21, Pg.253
* Oxford Illustrated Encyclopedia (revised version 2004), Oxford University Press, Pg.592,593
* Disappearing Wetlands, Helen J. Challand, Childrens Press Chicago 1992, used the whole book
* Birdlife South Africa News, June/July 2006 issue, pg.1
* http://www.endangeredspecieshandbook.org/aquatic_wetland3.php
* http://www.nctwr.org.au/consequences.html