Can planting trees stop desertification? A recent article (you can see a summary here) describes various plans to do just that.
One, known as the Great Green Wall, aims to plant a band of trees across Africa, just south of the current southern boundary of the Sahara Desert. Under discussion for decades and approved by the African Union in 2007—but with the funding and some of the logistics still to be worked out—the project would create a 9-mile-wide tree belt stretching for almost 5,000 miles coast to coast from Senegal to Djibouti.
Would it work? Similar efforts in China along the southern border of the Gobi Desert have resulted in the planting of about 40 billion trees, but many don’t survive, mostly due to lack of irrigation, and the Gobi is still expanding. And defining the borders of a desert is tricky: In a period of just a few years in the 1980s, the border of the Sahara moved 145 miles southward, then retreated more than 60 miles northward a few years later. Such shifts can take place more rapidly than newly planted trees could likely become established.
Some agronomists believe that rather than creating a dedicated tree belt, a better strategy is to encourage farmers to preserve trees on their land, shedding the idea that agricultural zones and tree zones should be separate. Unlike large, automated agribusiness where vast fields are necessary for mechanized harvesters to operate, many of the small farms in hot sub-Saharan Africa lend themselves to this method—the trees provide shade and protection for the crops, the irrigation of the crops also benefits the trees, and the mix of species provides at least some protection from pests and disease that can wipe out a single crop planted over a vast area. While not necessarily combining trees with agricultural crops, Israel has followed this mix-of-species technique in its very successful afforestation efforts.
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Upcoming Forester University Webinars
January 12th, 2012
Planning & Executing an Effective Pavement Preservation Program
As roadway networks and commercial vehicle loading continue to increase and Municipality taxation power remains limited, the need to effectively maintain and improve our pavement infrastructure is paramount. Join David Hein, V.P. of Transportation for ARA, to explore the key concepts of an effective pavement preservation program, program implementation needs and guidelines, and common roadblocks to successful implementation. Read more…
January 26th, 2012
5 Steps to Creating a Successful Public Outreach Campaign
Change starts with people. Whether your focus is stormwater pollution, energy conservation, pavement restoration, or recycling, a successful public outreach campaign resonates with your target audience and leads to long-lasting behavior change. Join Erica Hooper of SGA to explore a proven 5-step approach to crafting a successful outreach campaign based on real-world examples of the good, the bad, and the ugly. Read more…