Purpose of Walls
Most of those large walls were intended to keep out "undesirables," but not all. Some were built to keep in whoever might have wanted to leave. The "Berlin Wall" through the city of Berlin and later along the entire "iron curtain" was one of those.
Success of Walls
Many great walls provided only limited success. Like a chain which is only as strong as its weakest link, each wall also has its weak points. Once those are recognized by the "enemy," it's pretty much game over; the wall soon becomes breached and abandoned. History shows that only a few walls ever managed to achieve their original objective over any length of time.
New Great Wall
The latest Great New Wall idea is of a somewhat different kind. It's not meant to keep people in or out but nature. Its main reason is to provide "a defense against the rapid, expanding desertification of the Sahara." This Great Green Wall of Africa program is said to consist of a tree planting program across the southern edge of the Sahara desert and its arid neighbor, the Sahel, all told some 4,300 miles (7,000 km) in length.
The new wall is an ambitious project subscribed to by 12 countries with ample (financial) help and advice from the UN Environment Program, the Global Environment Facility and the World Bank. This wall of trees, envisaged to be 9 miles (15 km) wide is hoped to stretch across the entire width of the African continent from Senegal on the west to Djibouti in the east.
When looking at the effect of past Great Walls, the question which comes to mind is: Will the Great Green Wall of Africa be any more successful than its many predecessors?
Theory and Practice
In theory, trees are good. They provide for shade, soil stabilization, water table management, wood for heating and cooking, refuge for wildlife and so on.
In practice, though, forests rarely are seen by the inhabitants of any country as a natural bulwark against desertification and as soil and water table stabilizers. This is evident from numerous examples around the world, from the ancient Roman empire, which cut down the cedar forests of the Adriatic (to build galleons) to modern Africa (for example Kenya, which lost much of its natural tree cover due to "biofuel" use and conversion to agricultural land), to many other areas in southeast Asia, Africa, South America, and the rest of the world. The latter have all replaced large tracts of the natural plant cover with plantations of various sorts.
Wherever you look, nearly any engineering project of any scale starts with the cutting down of existing trees. While planting of new trees may well be in the design of the project, there is a substantial difference between a tiny sapling a couple of years old and a mature and towering tree which has an age of 100+ years.
Green Wall Project
The Great Green Wall Project across Africa is likely to suffer the same fate as other Great Walls - if it ever gets going at all. Already a decade in planning, it has the support of the 12 countries--as long as it is financed extensively "by other people's money." Of course, that involves funds from you and me.
More importantly, it is not just hoped to be a defense against desertification, it is to be accompanied by
ponds and other infrastructure developments.
The French "
Le Comite Scientifique Francais de la Desertification" points out some interesting advice which includes some common misconceptions:
- Misconception 1: The desert is a disease
- Misconception 2: The Sahel is being invaded by a sand sea
- Misconception 3: A great forest wall could be planted in uninhabited or sparsely inhabited regions
It is much more difficult to establish any forest than to cut it down. The UN IPCC's claims of a major component of the world's energy supply to come from "biofuel" as energy source is a disaster-in-waiting. For example, The UN's IPCC has claimed that in 40 years' time, close to 80% of the world's energy supply could be met by renewables with biomass as a major component of that. As I noted before, there is a great difference between renewABLE and renewED. Unfortunately, the difference appears to be lost with many of the UN functionaries.
Other Goals
Almost universally, one goal alone is never sufficient to receive widespread acceptance. Therefore, it's just about de rigueur that it must be combined with numerous other ideas. The same is the case for the new great green wall in Africa. For example, the project also entails "
water retention ponds, agricultural production systems and other income-generating activities, as well as basic social infrastructures." That's where the rubber really meets the road.
Having numerous water retention ponds along the stretch of the green wall may increase water availability for humans and livestock. However, they would most certainly also create new breeding grounds for mosquito and tsetse fly larvae and the bilharzia snail, adding more disease vectors for such afflictions as malaria, dengue fever, trypanosomiasis and schistosomiasis.
In short: Like many other UN and World Bank sponsored grand schemes, the new Great Green Wall of Africa project is more likely to fail than become a reality. There are too many conflicting interests in the various jurisdictions to come together. On top of that, the project may come with significant collateral damage and societal costs not foreseen by UN and World Bank bureaucrats.
