Question

I was watching a documentary about abandoned soviet structures and cities. At the beginning of the documentarya piece of drone footage is shownfeaturing the abandoned flats of pripyat from above. While watching it i noticed something very peculiar, there were several fullgrown shrubs and even a tree growing on top of the roofs of the flats. The red arrow points at a berch tree that's apparently growing on top of the rooftop as well. How is such a large plant able to grow there? I've seen plants grow in strange places in my own city Groningen as well. Here's an example of small shrubs that managed to grow out of asphalt. Here are a couple of pictures of 2 seedlings that are growing out of a hole of a rotten piece of wood. The hole does not go all the way through the wood, so the roots are not in contact with the soil. According to ChatGPT one explanation could be that over time, organic debris like leaves, bird droppings, and dead insects can accumulate on surfaces. This can decompose and form a thin layer of organic matter that serves as a growing medium for plants. But I can't believe that a tree such as the birch tree in the first video still could grow so large using only organic matter that deposited on the rooftop. So how does this work? Can trees and shrubs use different materials like asphalt or roofpanels to extract nutrients from when there is little to no soil available? If so, how do they do it?

Answer 1

Plants can grow in places with limited soil access because they can extract nutrients from decomposed organic matter. Epiphytic plants, including orchids and banyan trees, use specialized tissues to absorb moisture, while plants like mangroves have adapted to aquatic environments. Pioneer species initiate soil formation, enabling other species to grow.

Step-by-step explanation:

How Do Plants Grow in Unconventional Places?

Plants can exhibit remarkable resilience and adaptability, and some species have evolved to grow in conditions with limited access to soil. One key adaptation is the ability of certain plants to extract nutrients and moisture from accumulated organic matter. Over time, organic debris like leaves, bird droppings, and dead insects can decompose on surfaces such as rooftops or asphalt, creating a thin layer of nutrient-rich material. This layer can support the germination and growth of plant life, including shrubs and even trees such as the birch observed on the rooftops of Pripyat.

Epiphytic plants, including orchids and the banyan tree, are another example of plants growing without traditional soil. They can anchor themselves to other surfaces and absorb moisture through specialized tissue. Similarly, plants in aquatic environments, like mangroves and wild rice, develop specialized root structures that allow them to thrive in water-saturated, low-oxygen conditions. These adaptations allow them to grow in places where most plants cannot.

Pioneer species, such as lichens and bacteria, can colonize bare rock and contribute to soil formation, eventually allowing other plants to establish. Also, plants like grasses can grow in shallow soil, adding organic matter and improving the soil's ability to retain water. The plant community evolves as the soil quality improves, creating a habitable environment for a greater variety of plant species, including shrubs and trees.