My interest has always been on the impact of global warming on Zambezi and rovuma catchment areas. What will global warming contribute towards the water levels and fauna of these catchment.
These catchment are amongts the concetrated with worlds diversity, and one school of thought is that the evolution of fishes in these catchment has been contributed by the different water levels several thousand s of years being low and high at some point. This has led to emergence and divergence of fish species, presently ranking high among the colour polymorphism and hence preference from the aquarium traders.
How Will the impending excess or scartity of water affect the species diversity of this african rift valley??? ........
Hastings Zidana
=====================
AFP - Wednesday, July 11 10:25 am
PARIS (AFP) - Scientists on Wednesday said that the rise in global temperatures that has been detected over the past two decades cannot be blamed on the Sun, a theory espoused by climate-change sceptics.
British and Swiss researchers looked at data for radiation from the Sun, levels of which can cool or warm our planet's atmosphere.
They factored in a cycle which solar radiation goes through peaks and troughs of activity over a period of about 11 years.
Writing in Proceedings of the Royal Society A, a journal of Britain's de-facto academy of sciences, the team said that the Sun had been less active since 1985, even though global temperatures have continued to rise.
"Over the past 20 years, all the trends in the Sun that could have had an influence on the Earth's climate have been in the opposite direction to that required to explain the observed rise in global mean temperatures," they write.
The study is co-authored by Mike Lockwood of Britain's Rutherford Appleton Laboratory and Claus Froehlich of the World Radiation Centre in Switzerland.
The overwhelming consensus among scientists is that human activity is to blame for the rise in global temperatures. In its latest report, issued this year, the UN's Intergovernmental Panel on Climate Change (IPCC) said that this warming is already affecting the climate system.
Since 1900, the mean global atmospheric temperature has risen by 0.8 C (1.44 F), and the sea level by 10-20 centimetres (four to eight inches).
Levels of carbon dioxide (CO2), the main greenhouse gas, have risen by around a third since the Industrial Revolution and are now at their highest in 650,000 years. Eleven of the past 12 years rank among the dozen warmest years on record.
In the past few years, glaciers and snow and ice cover have fallen back sharply in alpine regions, the edges of the Greenland icesheet and on the Antarctic peninsula have shrunk, Arctic summer sea ice has thinned and retreated and Siberian and Canadian permafrost have shown signs of thaw and fallback.
Wednesday, July 11, 2007
Saturday, May 12, 2007
GLOBAL WARMING IS REAL
Fellow Biodiversity lovers
As we can see from the artcle below it clearly shows THAT GLOBAL WARIMNG IS REAL.
my questin has been and is always "What is our role as Malawians ?" Do the parliamentarians take this issue with a priority?.
The image clearly shows that Malawi is in the band of "Areas at most risk". Let us act now by putting in place necessary policy issues like-irrigation for all crop fields by the year 2030 or 2040, thats 10 yeras before the real thing is on our neck. We can do it there are several organisation dealing with global warimng and environment where, we can tap the resources let alone the credit income which they have just been written off by our creditors. As a country we can put that money to good use other than politicking by suggesting mitigation moves of glaobal warming.
Do not say I did not warn you, have a good reading below.
Hastings
=================Drying up and flooding out
May 10th 2007 NAIROBI From The Economist print editionRich countries may be largely to blame for adding climate change to Africa's litany of problems, but the continent's own politicians have yet to take it seriously
AT A recent African Union summit, Uganda's combustible president, Yoweri Museveni, declared climate change an act of aggression by the rich world against the poor one—and demanded compensation. The moral arguments on climate change are even murkier than arguments about other wrongs done to Africa, such as slavery, but Mr Museveni may have hit on something. If the predictions of the UN's Intergovernmental Panel on Climate Change (IPCC), hold true, climate change may have a graver effect on Africa than on any other continent; the final part of the panel's latest report has just been published (see article). Scientists now blame industrialisation (read, the rich world) for some of the warming. In any event, the contrast between poverty in Africa and carbon gluttony elsewhere is sharp. Why should the poorest die for the continued excesses of the richest?
The IPCC's most recent regional report certainly raises the spectre of rising mortality. It predicts a minimum 2.5°C increase in temperature in Africa by 2030; drylands bordering the deserts may get drier, wetlands bordering the rainforests may get wetter (see map). The panel suggests the supply of food in Africa will be “severely compromised” by climate change, with crop yields in danger of collapsing in some countries.
In the drylands, water may become a critical issue. Soaring temperatures and erratic rainfall may dry up surface water. Between 75m and 250m Africans, out of the 800m or so now living in sub-Saharan Africa, may be short of water. The soil will hold less moisture, bore-holes will become contaminated, and women and girls will have to walk ever greater distances to fetch water. Vegetative cover will recede. The IPCC guesses that 600,000 square kilometres (232,000 square miles) of cultivable land may be ruined.
Warming may also hurt animal habitats and biodiversity. More algae in freshwater lakes will hit fishing. The glaciers of Uganda's Rwenzori mountains, of Tanzania's Kilimanjaro and of Kenya's eponymous mountain may disappear; only seven of the 18 glaciers recorded on Mount Kenya in 1900 still remain. At the same time, a likely rise in sea levels may threaten the coastal infrastructure of northern Egypt, the Gambia, the Gulf of Guinea and Senegal.
There are two caveats to this gloomy scenario. The first is that some parts of Africa may benefit from climate change. Increased rainfall in highland areas in eastern Africa could, for example, be beneficial. Second, though climate-change models have improved, they have been unreliable in Africa. The broad outline is plain but the detail is guesswork.
Still, some scientists think that climate change may be even crueller to parts of Africa than the IPCC predicts. The important point, they say, is not the degree of warming but the continent's vulnerability to it. A University of Pretoria study estimates that Africa might lose $25 billion in crop failure due to rising temperatures and another $4 billion from less rain. The already impoverished drylands would suffer most. Some cite the war in Sudan's Darfur region as proof of the damage done by climate change, soil erosion and overpopulation.
Unfortunately, few African leaders have grasped the scale of the challenge posed by climate change. Most oil-producers have squandered their bonanza. Nigeria has failed to plan for how to stem the dreadful pollution in its oil-producing Delta region or to prevent desertification tearing at the fabric of its dry Muslim north. South Africa is only just beginning to own up to its coal addiction. Uganda's Mr Museveni is fighting off a rare insurrection from his supporters against plans to turn a piece of Ugandan rainforest over to farming. The World Meteorological Organisation says that weather-data collection in Africa has recently got worse, just as the need for accurate figures has grown; many of the automatic weather stations it helped set up have fallen into disrepair. The African Union has done little to sound the climate-change alarm.
Kenya's president, Mwai Kibaki, says that Africa should “join hands” with its friends in the rich world over climate change. He wants more carbon-trading projects to come to Africa; so far, most have gone to Asia. His advisers admit that Mr Kibaki's ambitious plan to turn Kenya into an industrial country by 2020 worries environmentalists, but say that reforestation, thermal power and better management of water and grazing would, if they materialised, offset the damage.
Africa emits far less carbon than other continents, so its recently faster-growing economies do not gravely menace its environment. Some rich-country consumers, however, want to punish African countries for airfreighting northwards some of their produce, from flowers to wine.
Hardier new varieties of staple crops, drip irrigation schemes and technologies such as solar power should help Africa adapt to climate change. But so can simple shifts in policy. For instance, a government decision in Burkina Faso to let farmers own the trees on their land has increased the country's tree cover.
Most vital of all is the cash—probably from rich countries—to pay for roads, schools, clinics and improvements in livestock management in the most vulnerable regions. Whether Mr Museveni's outrage will sway donors is unclear. As the G8 rich countries are failing so far to fulfil the promises they made in 2005 to boost aid to Africa, the continent should not expect much new money to protect the environment. In the short run, Africa's own politicians need to take a lead, even if the people most culpable for the damage done by climate change live elsewhere.
May 10th 2007 NAIROBI From The Economist print editionRich countries may be largely to blame for adding climate change to Africa's litany of problems, but the continent's own politicians have yet to take it seriously
AT A recent African Union summit, Uganda's combustible president, Yoweri Museveni, declared climate change an act of aggression by the rich world against the poor one—and demanded compensation. The moral arguments on climate change are even murkier than arguments about other wrongs done to Africa, such as slavery, but Mr Museveni may have hit on something. If the predictions of the UN's Intergovernmental Panel on Climate Change (IPCC), hold true, climate change may have a graver effect on Africa than on any other continent; the final part of the panel's latest report has just been published (see article). Scientists now blame industrialisation (read, the rich world) for some of the warming. In any event, the contrast between poverty in Africa and carbon gluttony elsewhere is sharp. Why should the poorest die for the continued excesses of the richest?
The IPCC's most recent regional report certainly raises the spectre of rising mortality. It predicts a minimum 2.5°C increase in temperature in Africa by 2030; drylands bordering the deserts may get drier, wetlands bordering the rainforests may get wetter (see map). The panel suggests the supply of food in Africa will be “severely compromised” by climate change, with crop yields in danger of collapsing in some countries.
In the drylands, water may become a critical issue. Soaring temperatures and erratic rainfall may dry up surface water. Between 75m and 250m Africans, out of the 800m or so now living in sub-Saharan Africa, may be short of water. The soil will hold less moisture, bore-holes will become contaminated, and women and girls will have to walk ever greater distances to fetch water. Vegetative cover will recede. The IPCC guesses that 600,000 square kilometres (232,000 square miles) of cultivable land may be ruined.
Warming may also hurt animal habitats and biodiversity. More algae in freshwater lakes will hit fishing. The glaciers of Uganda's Rwenzori mountains, of Tanzania's Kilimanjaro and of Kenya's eponymous mountain may disappear; only seven of the 18 glaciers recorded on Mount Kenya in 1900 still remain. At the same time, a likely rise in sea levels may threaten the coastal infrastructure of northern Egypt, the Gambia, the Gulf of Guinea and Senegal.
There are two caveats to this gloomy scenario. The first is that some parts of Africa may benefit from climate change. Increased rainfall in highland areas in eastern Africa could, for example, be beneficial. Second, though climate-change models have improved, they have been unreliable in Africa. The broad outline is plain but the detail is guesswork.
Still, some scientists think that climate change may be even crueller to parts of Africa than the IPCC predicts. The important point, they say, is not the degree of warming but the continent's vulnerability to it. A University of Pretoria study estimates that Africa might lose $25 billion in crop failure due to rising temperatures and another $4 billion from less rain. The already impoverished drylands would suffer most. Some cite the war in Sudan's Darfur region as proof of the damage done by climate change, soil erosion and overpopulation.
Unfortunately, few African leaders have grasped the scale of the challenge posed by climate change. Most oil-producers have squandered their bonanza. Nigeria has failed to plan for how to stem the dreadful pollution in its oil-producing Delta region or to prevent desertification tearing at the fabric of its dry Muslim north. South Africa is only just beginning to own up to its coal addiction. Uganda's Mr Museveni is fighting off a rare insurrection from his supporters against plans to turn a piece of Ugandan rainforest over to farming. The World Meteorological Organisation says that weather-data collection in Africa has recently got worse, just as the need for accurate figures has grown; many of the automatic weather stations it helped set up have fallen into disrepair. The African Union has done little to sound the climate-change alarm.
Kenya's president, Mwai Kibaki, says that Africa should “join hands” with its friends in the rich world over climate change. He wants more carbon-trading projects to come to Africa; so far, most have gone to Asia. His advisers admit that Mr Kibaki's ambitious plan to turn Kenya into an industrial country by 2020 worries environmentalists, but say that reforestation, thermal power and better management of water and grazing would, if they materialised, offset the damage.
Africa emits far less carbon than other continents, so its recently faster-growing economies do not gravely menace its environment. Some rich-country consumers, however, want to punish African countries for airfreighting northwards some of their produce, from flowers to wine.
Hardier new varieties of staple crops, drip irrigation schemes and technologies such as solar power should help Africa adapt to climate change. But so can simple shifts in policy. For instance, a government decision in Burkina Faso to let farmers own the trees on their land has increased the country's tree cover.
Most vital of all is the cash—probably from rich countries—to pay for roads, schools, clinics and improvements in livestock management in the most vulnerable regions. Whether Mr Museveni's outrage will sway donors is unclear. As the G8 rich countries are failing so far to fulfil the promises they made in 2005 to boost aid to Africa, the continent should not expect much new money to protect the environment. In the short run, Africa's own politicians need to take a lead, even if the people most culpable for the damage done by climate change live elsewhere.
Friday, March 30, 2007
FISH INTRODUCTIONS WITHIN LAKE MALAWI
The introduction of exotic fish species to areas where they do not naturally belong is a global problem. Apart from cases of exotic species, there are also many more cases of species transplant within the same watershed, this is the issue which mainly affects most of African and indeed Malawian water ecosystems.
What is of great concern to ecologists, enviromentalists, biologists and genetists alike is what happens next after an introduction has occurred. Mainly a concern is whether a fish species which has been introduced to a new ecosystem is going to establish itself in that new environment.
The law of nature dictates "survival of the fittest", this is equally true with the new introduced fish species to any ecosystem, whether it is a lake, river, reservoir or pond. The new species needs to have an added advantage over the native species in order to do well in the new habitant. If the ecosystem is already diverse enough and strong the new species has problems to deal with its survival. In most areas in the wolrd, aquatic ecosystems have been tampered enough so that their structures are no longer strong to resist the establishment of new species in their territories. This has been due to high human population in most shorelines, which have impacted these ecosystems to the extent of affecting their assemblages.
Lake Malawi is one of those ecosystems which has suffered human impacts due to increasing settlements and farming activities near or in the shore line. This has affected the breeding grounds of many fish species including, the most totted Lake Malawi Tilapia commonly known as 'Chambo". As if this is not enough, the Lake Malawi ecosystem is also at the moment suffering from fish transfers or what ecologists call it fish translocations. This is happening mostly with the most colourful species which are commonly known as "Mbuna". The high demand of the Malawian Mbuna to European and Asian markets has led fishermen to capture these tiny spcies as far as the northern waters and send them to the southern waters where they are freighted to outside markets. It is during these processes that some of the Mbuna species are dropped on the way and hence found to be where they do not belong.
At the moment it is not yet known whether these small species will be able to establish themselves in the new ecosystems. But the questions which we should aks ourselves as Malawians are: why do we have so many fish species coexisting in lake malawi? what mechanisms are these species using to coexists? why different fish colours in different geographic areas within the lake? what will be the response of the native species?
As one way of trying to answer these questions, I have put forward a proposal which is being funded by British Council. Anyone willing to help or collaborate in this venture just contact me using my email.
What is of great concern to ecologists, enviromentalists, biologists and genetists alike is what happens next after an introduction has occurred. Mainly a concern is whether a fish species which has been introduced to a new ecosystem is going to establish itself in that new environment.
The law of nature dictates "survival of the fittest", this is equally true with the new introduced fish species to any ecosystem, whether it is a lake, river, reservoir or pond. The new species needs to have an added advantage over the native species in order to do well in the new habitant. If the ecosystem is already diverse enough and strong the new species has problems to deal with its survival. In most areas in the wolrd, aquatic ecosystems have been tampered enough so that their structures are no longer strong to resist the establishment of new species in their territories. This has been due to high human population in most shorelines, which have impacted these ecosystems to the extent of affecting their assemblages.
Lake Malawi is one of those ecosystems which has suffered human impacts due to increasing settlements and farming activities near or in the shore line. This has affected the breeding grounds of many fish species including, the most totted Lake Malawi Tilapia commonly known as 'Chambo". As if this is not enough, the Lake Malawi ecosystem is also at the moment suffering from fish transfers or what ecologists call it fish translocations. This is happening mostly with the most colourful species which are commonly known as "Mbuna". The high demand of the Malawian Mbuna to European and Asian markets has led fishermen to capture these tiny spcies as far as the northern waters and send them to the southern waters where they are freighted to outside markets. It is during these processes that some of the Mbuna species are dropped on the way and hence found to be where they do not belong.
At the moment it is not yet known whether these small species will be able to establish themselves in the new ecosystems. But the questions which we should aks ourselves as Malawians are: why do we have so many fish species coexisting in lake malawi? what mechanisms are these species using to coexists? why different fish colours in different geographic areas within the lake? what will be the response of the native species?
As one way of trying to answer these questions, I have put forward a proposal which is being funded by British Council. Anyone willing to help or collaborate in this venture just contact me using my email.
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