Landscape changes at Chernobyl

Abstract

Thirty-two years ago, the Chernobyl nuclear accident changed the lives of many people, when one of the nuclear reactors exploded during a safety test. The explosion released huge amounts of radioactive materials like caesium, strontium, and plutonium into the atmosphere. High doses of radiation caused severe damage to the DNA of living beings, with direct impact on the changes suffered by the environment, either by causing instant death or by altering the fitness of the local biota. As people were evacuated from the surrounding areas, the land was left abandoned and the indirect changes caused by the alteration of land use are still unknown. Thus, the objective of this study was to analyse the state of primary production of the vegetation in the Chernobyl Exclusion Zone after the accident, comparing with its previous state. Through Normalized Difference Vegetation Index (NDVI) and radiation measurements, the relationship between these variables was assessed using Analysis of Variance (ANOVA) and Generalized Additive Models (GAM), to understand how the vegetation responded to the radiation exposure. The data was obtained through remote sensing, using available Landsat satellite imagery and sampled areas registered on the field. The results show that the NDVI increased over the years after the accident and that it is independent of the current radiation measured. This suggests that to some level of radiation exposure, the positive effects of land abandonment and/or the negative effects of radiation on abundance of herbivore species surpass the long term negative effects of radiation exposure on the vegetation. Nonetheless, above some radiation threshold level, primary production is expected to be negatively affected.

Are Vegetation Dynamics Impacted from a Nuclear Disaster? The Case of Chernobyl Using Remotely Sensed NDVI and Land Cover Data

“…A general outcome is the surprising resilience of plants and animals to chronic exposure to radiation. The results of the present study are in agreement with the findings of [30,31], that both showed an increase in NDVI values long after the accident, while they highlighted that humanity still has not yet reached a full understanding of the consequences of the Chernobyl nuclear accident. An explanation of the remarkable resilience of plants comes from [58], explaining the various mechanisms of plants to replace dead cells or tissues easier than animals, irrespective of the source of damage, i.e., due to attack by an animal or due to radiation.…”

Plants in the Light of Ionizing Radiation: What Have We Learned From Chernobyl, Fukushima, and Other “Hot” Places?

“…The Chernobyl Exclusion Zone is characterized by predominant cover with grasses and trees following the impact of the nuclear disaster. Santos et al (2019) used the Normalized Difference Vegetation Index (NDVI) derived from satellite images and measurements of ambient radiation from the ground. Remote sensing and Landsat satellite images across years were used to relate NDVI to background radiation.…”

“…The Chernobyl Exclusion Zone is now dominated by grasses and shrub/trees with the latter dominated by Scots pine and silver birch Betula pendula. Santos et al (2019) concluded that there were positive effects of abandonment of farmland for the abundance of some plant species, while there were negative impacts of exposure to ionizing radiation on the vegetation. Finally, Santos et al (2019) showed that the vegetation was negatively affected by a threshold level of ionizing radiation.…”

“…Santos et al (2019) concluded that there were positive effects of abandonment of farmland for the abundance of some plant species, while there were negative impacts of exposure to ionizing radiation on the vegetation. Finally, Santos et al (2019) showed that the vegetation was negatively affected by a threshold level of ionizing radiation. This suggests that level of ionizing radiation reduces the abundance of some, but not of other species of trees.…”

“…Fourth, we review the literature on how other organisms through herbivory and parasitism impact flowering plants and their performance. Fifth, we review studies of the effect of ionizing radiation on plant ecosystems (Santos et al, 2019). Finally, we provide future directions for research on the impact of ionizing radiation on flowering plants.…”