Nuclear fallout effects on an ecosystem

Surrounding wildlife and fauna were drastically affected by Chernobyl's explosions. Coniferous trees, which are plentiful in the surrounding landscape, were heavily affected due to their biological sensitivity to radiation exposure. Within days of the initial explosion many pine trees in a 4 km radius died, with lessening yet still harmful effects being observed up to 120 km away.[9] Many trees experienced interruptions in their growth, reproduction was crippled, and there were multiple observations of morphological changes. Hot particles also landed on these forests, causing holes and hollows to be burned into the trees. The surrounding soil was covered in radionuclides, which prevented substantial new growth. Deciduous trees such as Aspen, Birch, Alder, and Oak trees are more resistant to radiation exposure than coniferous trees, however they aren't immune. Damage seen on these trees was less harsh than observed on the pine trees. A lot of new deciduous growth suffered from necrosis, death of living tissue, and foliage on existing trees turned yellow and fell off. Deciduous trees resilience has allowed them to bounce back and they have populated where many coniferous trees, mostly pine, once stood.[9] Herbaceous vegetation was also affected by radiation fallout.[9] There were many observations of color changes in the cells, chlorophyll mutation, lack of flowering, growth depression, and vegetation death.[9]

Mammals are a highly radio-sensitive class, and observations of mice in the surrounding area of Chernobyl showed a population decrease.[9] Embryonic mortality increased as well, however, migration patterns of the rodents made the damaged population number increase once again.[9] Among the small rodents affected, it was observed that there were increasing issues in the blood and livers, which is a direct correlation to radiation exposure.[9] Issues such as liver cirrhosis, enlarged spleens, increased peroxide oxidation of tissue lipids, and a decrease in the levels of enzymes were all present in the rodents exposed to the radioactive blasts.[9] Larger wildlife didn't fare much better. Although most livestock were relocated a safe distance away, horses and cattle located on an isolated island 6 km away from the Chernobyl radioactivity were not spared.[9] Hyperthyroidism, stunted growth, and, of course, death plagued the animals left on the island.[9]

The loss of human population in Chernobyl, sometimes referred to as the "exclusion zone," has allowed the ecosystems to recover.[9] The use of herbicides, pesticides, and fertilizers has decreased because there is less agricultural activity.[9] Biodiversity of plants and wildlife has increased,[9] and animal populations have also increased.[9] However, radiation continues to impact the local wildlife.[9]

Factors such as rainfall, wind currents, and the initial explosions at Chernobyl themselves caused the nuclear fallout to spread throughout Europe, Asia, as well as parts of North America.[10] Not only was there a spread of these various radioactive elements previously mentioned, but there were also problems with what are known as hot particles.[10] The Chernobyl reactor didn't just expel aerosol particles, fuel particles, and radioactive gases, but there was an additional expulsion of Uranium fuel fused together with radionuclides.[10] These hot particles could spread for thousands of Kilometers and could produce concentrated substances in the form of raindrops known as Liquid hot particles.[10] These particles were potentially hazardous, even in low-level radiation areas.[10] The radioactive level in each individual hot particle could rise as high as 10 kBq, which is a fairly high dosage of radiation.[10] These liquid hot particle droplets could be absorbed in two main ways; ingestion through food or water, and inhalation.[10]