What Are Tree Canopies?

In botany (plant biology), the canopy can refer to the grouping of plant crowns which are in close proximity to each other. The crown of any plant is its uppermost part. When we take into account larger plant ecosystems such as forests, the canopy refers to the entire upper zone of all plant crowns together. This zone not only incorporates plant crowns, but also the various plants, animals and other organisms which live in it.

Forest ecology studies how the various organisms within a forest ecosystem interact and interrelate with each other. Tree canopies are a very important aspect of this study since their integrity influences the rest of the ecosystem greatly. The woody plants (mainly trees) whose crowns make up the canopy provide continuous cover to forests and jungles. This allows them to filter light, intercept precipitation and influence air movement. This influences various forest elements such as temperature, soil humidity and evapotranspiration of various plant species.

While tree canopies are important for many different types of forests, they are particularly vital in jungle ecosystems. You can learn more about what are jungle ecosystems and the difference between a jungle and a forest in our related articles.

The structure of the tree canopy is characterized by the stratified arrangement of the tree crowns. This arrangement provides a continuous roof over the lower canopy. At the top canopy, the tallest trees compete for sunlight. They do so by developing extensive canopies of intertwining branches to create a dense, protective canopy. This upper layer not only filters and modulates sunlight, but also regulates the temperature and humidity of the forest.

Diversity in tree height contributes to the formation of microhabitats, providing unique opportunities for a wide range of species to thrive. Since the trees themselves grow, move and develop, tree canopies are dynamic habitats which can change significantly over time. This is influenced by how different tree species and even individual trees compete for resources, especially light.

The complex structure of tree canopies is not only visually striking, but it is a vital element in the health and resilience of different types of forest ecosystems. This is thanks to the fact it supports biodiversity, regulates local climate and influences carbon sequestration, among other important processes.

In addition to the trees that make up the primary structure of the canopy, there are many other plant species that can live in the canopy. This includes climbing plants and epiphytes, the latter being a type of plant that grows on another. These are most common in tropical and subtropical rainforests.

The diversity of epiphytes and arthropods living in tee canopies attracts many birds and other animals due to the increase in available food resources. In turn, epiphytes are important because they contribute to the nutrient cycle. They do so by obtaining nutrients and transferring them to other members of the ecosystem.

Now we know what are tree canopies in biology and their characteristics, we can discover more about why they are so important for forest ecosystems. We have already mentioned some of them, but we can look more closely at why tree canopies are so important:

• Contributes to the water cycle: woody species present in the tree canopy play a vital role in the hydrological cycle. Through evapotranspiration, they release water vapor into the atmosphere, contributing to cloud formation and the precipitation cycle. This process is essential to maintain climate patterns and water availability in various ecosystems, not just the forest itself.
  
  
• Prevents soil erosion and flooding: the presence of numerous tree species in the canopy affects the dynamics of the water cycle. It reduces the impact of water dropping onto the soil below. In doing so, it reduces the erosive process, increases the infiltration and retention of water, and controls water runoff. In controlling water runoff, it helps to prevent and avoid flooding.
  
  
• Provides refuges for biodiversity: under the tree canopies there is a great diversity of animals and plants that are provided favorable place with optimal conditions to develop, reproduce and survive. The tree canopy is home to most species, many of them endemic, that are not found anywhere else in the forest. This is because there is a wide variety of resources and ecological niches available.
  
  
• Mitigates and adapts climate change: tree canopies play a crucial role in the mitigation and adaptation of climate change. This is due to their ability to capture carbon dioxide, one of the most impactful greenhouse gases. They do so by storing it in their biomass. They also function as a barrier against extreme climate events, conserve biodiversity, turn ecosystems into more resilient environments, among other functions.
  
  
• Improves air quality: the vegetation present in the canopy absorbs atmospheric pollutants, improving air quality.
  
  
• Maintains soil moisture: the canopy can retain solar radiation, causing the soil to not heat up as quickly and preventing rapid evaporation. In this way, the humidity of the lower strata is maintained, giving decomposer organisms such as fungi greater opportunity to develop.
  
  
• Essential for conservation: conducting research in the canopy is of utmost importance to be able to design management plans that are capable of conserving these forest environments.

Unfortunately, the canopy currently suffers various threats. These include deforestation, land use conversion, indiscriminate extraction of natural resources, the introduction of invasive exotic species, the spread of new diseases and climate change. For this reason, conservation and protection efforts are vital for our world's forests.

Now you know about how tree canopies affect various ecosystems, you might be interested to know more about the different types of trees which create them.

If you want to read similar articles to What Are Tree Canopies?, we recommend you visit our Ecosystems category.