Should we plant trees in the desert to combat climate change? – Referus

Reforestation is one of our best tools for combating climate change. In the tropics, forests have been reported to absorb tens of millions of tons of carbon dioxide annually. A mature tree can absorb up to 30 pounds (48 kg) of CO2 per year. In the US, our forests account for 14% of all annual carbon dioxide emissions, according to the nonprofit organization American Forests. There is no way to a neutral climate without forests and trees.

Many businesses such as Salesforce and Microsoft finance the planting of trees in veld fires and on farmland. But the stealth-phase Undesert is working on a new border for reforestation.

As you can guess from the name, the company is focused on planting trees in the desert, especially the desert shrublands in the Alamogordo region of New Mexico. Nicholas Seet, CEO of Undesert, calls his company “climate” – doing something to reduce the air emissions now that the rest of the world is participating.

But should we be planting trees in the desert?

“There is a current debate about whether arid areas are suitable for reforestation for global climate change purposes,” said Niall Hanan, a professor of archeology at the Department of Plant Sciences and Environmental Sciences at New University State University of New Mexico State.

Seet called the shrublands a “little used, empty area,” but Hanan emphasized that these ancient ecosystems were healthy, not just deforested. And there is a reason why deserts do not have trees.

“If [deserts] they were good for trees and they would probably have trees in them, ”said Hanan. Trees need sunlight, CO2 and water to live. Deserts are severely deficient in one of these ingredients, preventing many trees from growing naturally. But that is one problem that Undesert has created.

Undesert has developed a desalination technology to produce 20 liters of water in 24 hours and can work with salt water previously previously high in salty osmosis.

“The problem with [reverse osmosis] technology has a lot of garbage that can no longer be filtered, ”says Seet. “We can restore osmosis brine to our system and get clean water and salt.”

Undesert has removed bottles of traditional salt-extracting technology from the hot sun as the sun heats up the evaporation salt lake to create clean, coarse water on the roof of the house. Undesert developed a water-based module design and was able to increase the efficiency of five evaporation pools. Instead of thickening the roof, thickening occurs in a separate room cooled with tubes with cool rotating water. In this system more than 93% of saline water is available as pure water. The whole process uses the sun in a microgrid which makes the process smaller with carbon emissions.

Undesert is working with the Navajo tribes to find a brackish groundwater technology to extract salt from water that has become unusable due to salinity. The company then used drip irrigation to supply salt water to Afghan pines, and Undesert decided to use the trees for reforestation. The company has planted 16 of these trees so far. Undesert chose Afghan pine because it is hardy in the desert, needs little water, and grows fast, tall and straight. The company also has 50 ponderosa pine trees under its irrigation system because its root system is often drought tolerant. But even if trees receive a sufficient amount of water, there are other natural factors such as temperature that can affect the survival of plants.

There is no way to a neutral climate without forests and trees.

According to Undesert, the small display of trees supplied with solar salt water has been in operation since September 2021, and shows healthy growth. This area has great solar power and salt water found underground. Also the Alamogordo region where the exhibition is located near the Sacramento Ranger District with Douglas fir and ponderosa pine forests and many more before it was cleared so that the railway tracks could be repaired. All of these factors give Undesert hope that their trees will succeed.

But then there is scalability. Having a large forest irrigation system is not possible. And using groundwater salt may work in New Mexico, but Hanan noted that many deserts are not near the sea and have no access to groundwater. Costs, labor and maintenance will be added immediately. Even trees can cost up to $ 1 million per square mile, even if each plant costs as little as $ 10, according to Hanan. Most desert dwellers around the world do not have access to these types of funds.

And just getting seedlings is already a major problem for reforestation efforts.

“Even getting 400 in the first hectare can be difficult,” Hanan wrote in an email. “It is unlikely that the timber industry in the southwest (or western US) would supply the required 100,000 seedlings per square mile, let alone the larger area.”

But there are still many questions beyond the basics.

“In a water-scarce region, such as the southwestern US,” says Matthew Hurteau, professor of forestry and fire resources at the University of New Mexico, “if technology is available at a lower cost and at a lower cost of air purification. the water, the trees that grow in the desert are a good use of that water? ”

Reducing carbon emissions and providing benefits to local communities through tree planting could be a significant use of this water, but experts like Hanan and Hurteau can expect to see a detailed analysis of profit costs answering questions such as:

  • How well does this land fit into trees?
  • Are these the right plants?
  • Are they indigenous or rare species?
  • What will they do with existing ecosystems?
  • What will be lost by adding trees to these systems?

And will the stored carbon actually be enough to make a dent in our carbon problem? Hanan is skeptical because trees planted in the desert will certainly not be large rainforest trees, and they will probably have a biomass component. Desert trees may not be the lungs of the earth, but can they or should they be a small odor in this process?