Why Do Cacti Survive in Deserts?

Cacti have adapted to survive in extreme desert heat.

Desert plants have to be strong to survive despite extreme levels of heat. There are several reasons that cacti are able to thrive there even when water is scarce and the ravenous sun bares down on them.

Shallow Roots

Cacti have shallow root systems that tend to spread outwards from the stem rather than down into the soil. This root system allows the cacti to gather large quantities of water when rain is abundant, which it uses to feed itself during dry times. The cactus stores the water in its stem for future use.

Photosynthesis

Cacti utilize a special form of photosynthesis called Crassulacean Acid Metabolism (CAM) Photosynthesis. CAM Photosynthesis enables the plant to convert gasses primarily at night when the weather is coolest. This increases the efficiency of the cactus' water preservation process.

Skin

The tough exterior skin of the desert cactus protects it against hungry animals and discourages humans from using it. The stem also offers shade for the cactus and prevents it from becoming dehydrated or parched.

References

• Desert USA: Desert Plant Survival
• Cactus Museum: Cactus Survival Characteristics