forests > newsfile > forest destruction fuels east africa's drought
Forest destruction fuels East Africa's droughtPosted: 17 Jan 2006
Destruction of East Africa's forests and climate change, are among the causes of the drought which is biting across parts of East Africa threatening misery for millions of people and their livestock, says Klaus Toepfer, head of the UN Environment Programme (UNEP).
The causes of the drought are numerous including issues of good governance and conflicts in water scarce regions, he said. But the drought also has strong links with on-going environmental damage to forests, grasslands, wetlands and other critical ecosystems as well as global climate change.
Mr Toepfer urged countries in the region to invest in and rehabilitate their �natural or nature capital� in order to buffer vulnerable communities against future droughts.
He also urged donor countries to back such schemes as vital lynch pins for overcoming poverty and delivering sustainable and long lasting economic development while taking every possible measure to reduce the emissions of fossil fuels that are forcing up global temperatures.
�Drought is no stranger to the peoples of East Africa. It is a natural climatic phenomenon. What has dramatically changed in recent decades is the ability of nature to supply essential services like water and moisture during hard times. This is because so much of nature�s water and rain-supplying services have been damaged, destroyed or cleared,� said Mr Toepfer.
�These facts are especially poignant when you factor in the impact of climate change which is triggering more extreme weather events like droughts,� he added.
Rainfall over the past year has been poor and the recent rainy season of October to December 2005 has been dismal, according to the Kenyan Meteorological Services.
School textbooks commonly imply that clouds and precipitation are generated by evaporation from the oceans and the seas. The clouds, rising over hilly areas, then release this moisture as rain, which falls onto the land and is returned to the sea via rivers and streams.
But Christian Lambrechts, an expert in UNEP�s Division of Early Warning and Assessment, said this commonly held belief told only part of the story, hiding the vital role of vegetation such as forests in generating showers and rain.
�Globally something like 62 per cent of precipitation occurs over land as a result of evapo-transpiration from lakes and wetlands and dense vegetation, in particular forests pumping water held in the soils, into the air. In comparison only around 38 per cent of precipitation is generated over oceans and seas,� he explained.
�It is impossible to do anything about precipitation from oceans and seas but there is a lot we can do about the land. Trees not only assist the land in absorbing water when it rains, helping to feed rivers and lakes, wetland and underground aquifers. But they also act as natural pumps, bringing moisture from around two metres below into the air. Here it can fall back as showers and rainfall,� said Mr Lambrechts.
He said that the amount of average rainfall in an East African city like Nairobi was around 1,200 mm a year whereas in Paris, France, it was less averaging around 800 to 900mm a year.The difference is that the rainfall in France is characterised by smaller but more frequent rainfall whereas in Nairobi it tends to fall in larger less frequent amounts.
Mr Lambrechts said it was therefore even more crucial that the Kenya invested in vegetation as one way of storing and returning moisture to the air so as to increase the chances of regular rainfall throughout the year.
Just how much forest a country such as Kenya has lost is unclear, but is significant. Wangari Maathai, the former Kenya assistant environment minister and Nobel peace prize winner, has estimated that a country needs to maintain at least 10 per cent indigenous forest cover to achieve sustainable development.
It is estimated that Kenya currently has under two per cent of such forest cover left.
In response to the drought of 1999-2000, UNEP compiled a report which estimated that in the short period between between 2000 and 2003 major water catchment areas like Mount Kenya forest, the Mau forest, Mount Elgon�s forests and the Cherangani forest were deforested by between 0.2 per cent and over two per cent.
�These forests together with the Aberdares constitute 91 per cent of the total water catchments protection forest value in the country,� says the report.
A more detailed study, on Changes in Forest Cover in Kenya�s Five �Water Towers� 2000-2003 estimates that the Mau complex lost over 7,000 hectares of forest during this three year period. This area feeds all but one of Kenya�s rivers west of the Rift Valley including the Yala, Mara, Njoro, and Molo rivers. These in turn drain into key lakes including Baringo, Nakuru, Turkana and Victoria.
Many of these areas are also key income-generating tourist destinations and nationally and globally important reserves including the Maasai Mara, Serengeti and Kakamega Forest Reserve.
A follow up aerial survey in 2005 shows that the destruction of the Mau complex continues with encroachment of charcoal burning operations, shambas and other developments now impacting the entire western part of the Maasai Mau forest. Heavily impacted areas now cover just over 11,000 square km.
Mr Lambrechts, who has just returned from a field trip to Sondang peak in the north east part of the Cheranganis which is the upper catchment of the Turkwel River in Pokot land, said the forest there was now being clear felled leading to acute erosion of the land.
The impact of loss of vegetation goes further. A recent report carried out for Kengen, the Kenya electricity company, shows that the Masinga dam, which provides over 50 per cent of the country�s electricity is silting up as a result of forest loss upstream.
It also notes that the decline in global coffee prices has led to a decline in maintenance of coffee plantations and in terracing. This has added to erosion and soils entering the rivers.
It is estimated that the Masinga dam has lost 20 per cent of its capacity to siltation since it was built 25 years ago. And it would require 1,000 large trucks to work non-stop for six years to clear it out.
In countries like Costa Rica, communities upstream are given eco-payments by hydro-electric companies to maintain forests rather than chop them down, as it is cheaper to do this than try and dredge out dams or build new ones.