TUESDAY, NOVEMBER 15, 2011
Desert Forestry Gaining Traction
Considering that I posted on this five years ago and wrote to the subject long before, it is gratifying to see progress today in a range of small private initiatives.
Combine that with the rapid expansion of acacia culture in the Sahel itself and one can readily believe that the reclamation of the Sahara is actually beginning.
Yet put this in perspective. The Sahara is and never was a natural desert. I completely believe it was produced by human agricultural practices during the Bronze Age. A real long term desert has its own evolved ecosystem that makes it quite unmistakable. North Africa looks like a land wasted.
For that reason any and all efforts to restore forests will easily payoff because as I have posted, starting on the outside brings the moisture with you as you walk it in. Been greedy, I want to accelerate it all in as many ways as possible. However, simple best practice and a thousand years will also win.
One thing immediately suggested from the pictures here is that it would be possible to plant wide forested fence rows in a mile by mile grid over the whole desert needing a fraction of the moisture a full forestration would call for. This would sharply quell the winds at the surface and end the dust migration while establishing refugia in the natural cells to individually optimize.
Set this on the southern margin of the Sahara and I suspect plenty of farmers will happily work up the cells into productive lands with a natural acacia cover to work with.
Since we are building fence rows, I would go the extra mile and establish thorn borders to discourage wild life passing into the cells themselves. They would be naturally channeled along the fence row itself and be nervous of open ground in the cells.
Scarce water may often be sufficient to support the fence rows them selves since it will represent less than five percent of the total need.
As far as the article’s title question is concerned, the forest absorbs energy and moderates surface climate. This will produce a warmer Europe and a moderated Asia East of the Mediterranean.
And rather than giant greenhouse by the sea, it is likely way more practical to plant mangrove marshes on the coast to produce the necessary humidity to harvest immediately downwind.
The Big Question: Can planting forests in deserts cool the planet?
Vishal MehraNov 12 2011
Can planting forests in deserts cool the planet?
Desert forestThe tree cover would also bring more rain–about 700 to 1200 millimeters per year–and clouds, which help reflect the sun’s rays back into space.
Why are we asking this now?
Converting the sandy stretches of desert to lush green forests sounds weird. But this is what has been of late proposed so as to counter the huge Carbon emission of the atmosphere. That too, in a scenario when deforestation is happening in a large scale across the world. Scientists have come out with an option of converting deserts like theSahara into forests by large scale plantation and effective watering techniques.
There is a large scale denudation of forest and for est resources. This happens due to natural disasters as well as those by human intervention. Forest fire engulfs vast area of forests around the world. Hence efforts should be made at a large scale to replace our lost forests. With advancements in the science of molecular biology combined with modern agricultural techniques, this goal is not far to achieve.
Is it really that serious?
Trees as we know are the renewable wealth of our ecosystem. The importance of trees can be highlighted in many ways. Lot of Co2 is emitted by way of human habitation and burning of fossil fuels. This Co2 is replenished by forests trees through the process of photosynthesis wherein they use up this CO2 and release O2 back into the atmosphere. Trees offer a major resistance to erosion of soil through water and wind. When rain falls on the thick forest foliage, the water infiltrates into the ground through the leaves thus making seepage easy. Also trees provide good wind barriers. Forest covers let in cool air in summer and warm air in winter. Apart from the aesthetic pleasure they offer, trees also act as a main factor in maintaining the temperature of the region.
What others are saying?
On planting the Sahara desert with trees, atmospheric scientist Richard Anthes, president of the University Corporation for Atmospheric Research in Boulder, Coloradoopines that “the proposal is incredibly important and definitely worth taking seriously and looking into further. The benefits could be enormous and go well beyond carbon sequestration,”
Regarding the cost of afforestation of Sahara, the cost has been worked out to $2 trillion per year. The cost of $2 trillion compares roughly with the cost of capturing the carbon emission of the atmosphere. Leonard Ornstein, a cell biologist at the Mount Sinai Schoolof Medicine in New York quips “Any solution to climate change has to be a multitrillion-dollar project, the issue is what the payback is.”He argues, “In several decades, the forests could be sustainably harvested as a source of fuel for wood-burning power plants, making them a nearly carbon-neutral energy source”.
Project Sahara Forest
Project Sahara ForestThe project has a very sound basic principle and all that fresh water can be easily used to maintain many ecosystems that would be rich in both sunlight and moisture.
Project Sahara has been envisaged by scientists as a very successful one. Taking into consideration the benefit of turning the desert into farming spaces, the main one is feeding the growing population of the world. The project sound very promising. The main source of water is the sea, which is made usable using desalination plants. Studies show that if the Sahara is to be planted with trees, it would reduce the temperature of the desert by 80. It is also estimated that a tree cover on the Sahara can bring in precipitation of about 700-1200 mm/year apart from the benefits of reflecting the sun’s rays back into the clouds by the forest cover.
Also if planted with trees, the forest in Sahara alone would recycle 8 billion tons of Carbon/year which equals the total Carbon emitted by human habitation. Trees like Eucalyptus, which are identified to be heat tolerant are found to adapt well to the desert soil, if provided with ample irrigation.
2. Researcher transforms desert into lush green garden
Desert in lush green garden The idea started to excel with the first figs starting to grow in just four months.
Researcher Geoff Lawton of Permaculture Research Institute has made an achievement of sorts. He has converted a span of desert into a green farm growing food trees, plants and mushrooms. Situated 2 Km from Dead Sea, the land was made pliable by effective rain water harvesting and methods of evaporation barriers.
3. Man Plants Forest in Tengger Desert
Tengger DesertIt is immensely difficult for a tree to survive in the Tengger Desert as its average annual rainfall is about 100 millimeters.
Living amidst a forest of 10000 trees, Wang Daqing, a native of Mongolia, takes pride in having converted around 3 Hectares of desert area into forest. The area, which received a very meagre rainfall, was irrigated with water from a well in the area. Through his hard work and his yearning to contribute to the mother earth, Daqing’s work is worth emulating.
4. A solution to reverse Africa’s growing deserts
African desertGroasis, an ingenious passive ‘water incubator’ collects dew drops, making reforestation in barren lands possible.
` Pieter Hoff, a Dutch inventor has come out with an idea of a Waterboxx, which supplies water through passive drip irrigation system to the trees root system. The dew formed in the night is channelized to the tree roots through this system. This ‘water battery’ takes advantage of the differential temperature of day and night of deserts to reach water to the trees.
4. The main hurdles
In a reforestation or afforestation process, there are major natural as well as manmade hurdles. The main ones are:
a. Damage due to rodents and other grazing animals
b. Soil deficiencies
c. Extreme weather conditions
d. Poor tree stock
e. Inadequate site preparation
f. Presence of unwanted weeds.
What can be done?
A combination of huge greenhouses combined with concentrated solar power would help us achieve the goal of tree planting in deserts. In the greenhouses, the solar power to evaporate seawater and then pump the damp, cool air through the greenhouse. There is a mass awakening in support of desert afforestation programmes. For example the Hitachi group of Companies, to celebrate their 100th anniversary organised desert afforestation tours in association with an NGO at the Horqin desert in Inner Mongolia.
So everyone, rise and awake to this need of the hour and protect our planet earth!