Step 1: Terraform deserts into green areas that require rain.
Step 2: Local climates change.
Step 3: Rain amounts change due to local climate change.
Step 4: Unforeseen consequences. Previous areas that used to get enough rain now see drought conditions worsen.
"Deserts are hard to reclaim because plants cannot survive on shifting sand..."
I always figured that deserts were hard to reclaim because non-desert plants can't survive without water. As cyanobacteria are one of the oldest species on the planet, I'm also rather surprised to hear that anyplace that they could sustainably colonize hasn't already been colonized.
Though vegetation plays a major role in determining the biological composition of the soil, studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan.
The goal is to create a crust over the top that resists erosion and gives plants a place to grow. Once the plants are established, they further resist erosion.
It's a little unintuitive that heavy rain can sometimes promote desertification. When there's lots of plants, the rain soaks into the ground and helps them to grow. If the plants are removed (through overgrazing, unsustainable agriculture, drought, etc.), it washes aw
That's neat, I'm glad it's working, I just hope it doesn't leave yet another toxic debt. Cyanobacteria commonly produce toxins.
Step 2: Local climates change.
Step 3: Rain amounts change due to local climate change.
Step 4: Unforeseen consequences. Previous areas that used to get enough rain now see drought conditions worsen.
Wikipedia has a summary of the causes of desertification [wikipedia.org]. The most relevant part:
Though vegetation plays a major role in determining the biological composition of the soil, studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan.
The goal is to create a crust over the top that resists erosion and gives plants a place to grow. Once the plants are established, they further resist erosion.
It's a little unintuitive that heavy rain can sometimes promote desertification. When there's lots of plants, the rain soaks into the ground and helps them to grow. If the plants are removed (through overgrazing, unsustainable agriculture, drought, etc.), it washes aw
Saturated brine is a pretty hostile environment, which is what you would eventually get. The water evaporates, the salt sticks around.