Earth restoration in your back yard: Harnessing the hydrological cycle in dry places

Feb 2024

In the intricate tapestry of backyard ecosystems, an often underestimated yet crucial factor is water retention. From arid deserts to lush rainforests, understanding and enhancing water retention can profoundly influence ecosystem restoration efforts, and it need not be complex. However, arid climates do tend to be the most problematic in terms of ecosystem resilience today. In locales grappling with water scarcity – such as the arid landscapes of Africa, the Middle East, Asia and Australia, the western coastline of South Africa, the American Southwest and now vast areas in Europe – effective water retention is a lifeline. But how do we tackle this international environmental crisis when we can’t even fix these problems at home? The good news is that there are answers and they are achievable without having to study a science and agriculture degree. It’s called ecosystem restoration, and that can be done at ALL scales. The key to success is, of course, having an understanding of the problem and then the knowledge of how it’s done. So let’s start here…

Image credit: FAO

Why is water scarcity increasing?

Most people know by now that ongoing ecosystem degradation due to lack of water is negatively impacting carbon sequestration, dust emissions, and water cycles which is contributing to loss of biodiversity, agriculture, human health, and land degradation feedback loops. The land degradation feedback loop is a constant cycle of declining precipitation, which leads to the lack of vegetation, resulting in increased soil erosion. This in turn increases loss of soil nutrients that leads to more loss in vegetation cover. The result? Decreased evapotranspiration which closes the loop with more loss in precipitation.

An example of the water cycle. When precipitation occurs, water flow is dependent on soil porosity, ground cover, compaction, and slope. Water runs off and away from the initial rainfall location if the soil is dry and hard (compaction) and if the slope is downhill. Image credit: Chandel, A. (2024). Satellite-Based Remote Sensing Approaches for Estimating Evapotranspiration from Agricultural Systems

Google Earth aerial view of Prescott, Arizona 2024. An example of an arid climate and severe land degradation.

Taking action to reverse these conditions

Planting a variety of arid, endemic species of vegetation to break up the soil’s dense, nonporous top layer helps to reverse the soil condition, creating some breathing room, so to speak. The soil, much like plants, requires oxygen and a network of tiny channels to facilitate water movement. Introducing plants with strong taproots becomes a strategic starting point, as they can penetrate the soil at lower depths – creating space for additional plant growth – and can access deeper water tables that shallow plant roots cannot. Plants with taproots also provide extra stability via their longer and stronger root systems that hold onto the soil in adverse weather conditions, protecting it against erosion. This approach enhances the effectiveness of water penetration, allowing stored water to replenish existing vegetation. Consequently, this enables plants and trees to undergo evapotranspiration, releasing water vapor back into the atmosphere where it becomes part of the hydrologic cycle.

Here, endemic and drought-tolerant plants thrive together thanks to ground cover methods using small rocks and pebbles. This keeps soil cool, allows water to reach the plant’s roots, and prevents evaporation in hot weather. The water cycles through the plants, returning to the atmosphere for the next round of precipitation. Image credit: www.epa.gov

Sunken beds are a great strategy for planting and water retention in dry landscapes and are especially efficient in back yards. This soil is quite dry and weathered from wind and sun erosion and leached of nutrients and organic plant matter. By creating this type of design, you can fill these holes with compost and larger debris that will help feed the soil as it decomposes and adds extra space for water to percolate. The dips in the beds will catch excess water, allow it to stay around longer and seep into the soil. This will eventually lead to more water reaching the water table. And don’t forget about covering that bare soil with ground cover to avoid evaporation. Image credit: www.reformstead.com

We are not only stewards of our own back yards but stewards of the planet as well. You may not think that making small changes where you live has larger impacts in the region, but it absolutely does. Think about it this way, if your neighbors see the positive impact that you have created by simple actions, they will be more inspired to try these techniques too. Maybe they see that your ground has turned greener, maybe they notice that you have more birds visiting and more bees and butterflies dropping by. Maybe they see that you are able to harness the very little water that does fall in your region. Once more people in your community start acting in unison, that’s when we see beautiful change unfold, and start feeling the effects of a cooler climate, more precipitation, and more success in growing plants and food. People around the world are starting to experiment with large-scale restoration plans that include greening the deserts, regreening desertified plateaus and the sparse arid regions that have been previously dubbed as inhabitable, so why don’t you give it a try at home? What’s to lose at this point?

Every single human holds the potential to make a global impact. But we need to have the knowledge. And that’s why we are here! Ecosystem Restoration Communities support restoration around the world, in all climates, and of all sizes. Come along for the ride and get dirty for the planet with us. Together we can create a more resilient world.

Planting date palms at ERC Habiba Community, Egypt

Header image: ERC Dryland Solutions in Somalia, where there are highly degraded soils and declining ecosystems.