Blog Post #3 impact of light pollution

My inquiry question is “”What are the effects of urbanization on biodiversity and ecosystem health?” and the subtopic I will be researching in this blog post is “What is the impact of and light pollution from urban areas?”

Light pollution can be considered a pollutant, however in a different manner than traditional pollutants like plastic, pesticides, or carbon dioxide. Light pollution is often classified as an environmental pollutant for it interferes with nature cycles, wildlife and human health. The primary source of light pollution comes from outdoor lights that emit light up or sideways. When the light escapes upward it scatters in the atmosphere and diminishes the visibility of the stars and night sky.

Artificial light at night can disrupt natural light-dark cycles, affecting ecosystems and wildlife. Many species rely on the natural cycle of daylight and darkness for behaviors such as feeding, reproduction, migration, and sleep. Light pollution can interfere with these behaviors, leading to ecological imbalances. An example is that Light pollution influences the timing and duration of seasonal cycles, such as the beginning of spring and fall, by artificially extending daylight hours or creating continuous illumination at night. This can disrupt natural cues that trigger biological processes like hibernation, migration and plant dormancy, leading to mismatches between species interactions and environmental conditions.

Light pollution significantly impacts wildlife in various ways, including disrupting natural behaviors and affecting ecosystems. Artificial light at night can attract, repel, or disorient wildlife, leading to negative consequences. Nocturnal animals that are dependant on the lack of light are greatly affected. Nocturnal animals, such as insects, birds, mammals, and amphibians, are particularly affected by light pollution. It can interfere with their foraging, communication, navigation, and predator avoidance behaviors. For example, birds may become disoriented by city lights, disrupting their migration patterns and increasing collision risks with buildings. Light pollution can also impact ecosystems by altering natural light-dark cycles. This disruption can affect plant growth, pollination, seed dispersal, predator-prey interactions, and nutrient cycling. For instance, artificial lighting near shorelines can disturb marine life, including sea turtle hatchlings and nesting sea birds.

Light pollution has significant impacts on human health, affecting various aspects such as sleep, mental well-being, and physical health. Nocturnal light exposure can interfere with the production of melatonin, a hormone that regulates sleep cycles. This disruption can lead to insomnia, sleep disturbances, and reduced sleep quality, impacting overall health. Excessive artificial light exposure, particularly at night, has been linked to an increased risk of mood disorders such as depression and anxiety. The melatonin suppression may contribute to these mental health issues. Light pollution also disrupts circadian rhythms, affecting hormone levels and potentially contributing to cancer development.

ressources used:

1. https://education.nationalgeographic.org/resource/light-pollution/

2. https://darksky.org/resources/what-is-light-pollution

3. https://www.britannica.com/science/light-pollution

4. https://www.nps.gov/subjects/nightskies/sources.htm#:~:text=The%20primary%20cause%20of%20light,diminishing%20the%20view%20of%20it.

5. https://www.thelandbetween.ca/2020/02/the-birds-and-the-bees-and-dont-forget-the-trees-the-effect-of-light-pollution-on-the-natural-world/

6. https://appliedsciences.nasa.gov/our-impact/story/brighter-neighborhoods-harm-human-health