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Why defining impacts is important

Read this article to learn about the significance of impacts and their global implications on biodiversity, ecosystems, communities, and heritage.
Construction of Hydro Power Stations on the river

The significance of defining impacts may appear self-evident – an impact implies a result that necessitates consideration or recognition, based on whether it is favourable or unfavourable.

Furthermore, comprehending the scale and extent of impacts is crucial to figuring out the appropriate actions to take, developing alternatives or mitigations, and understanding their interconnections. Precisely defining the nature of the impact makes for a more efficient ranking process, ending in a decision on whether or not to proceed with a project.

However, it is crucial to situate this question in a broader context. Defining impacts and identifying them is vital on a global scale. For instance, the 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services has highlighted that biodiversity is diminishing at an alarming rate, with the average abundance of native species in most land-based habitats have declined by at least 20% since 1900. Many activities that attract an Environmental Impact Assessment (EIA) have significant effects on biodiversity. Mining, for example, causes acid mine drainage, heavy metal contamination, erosion, and sedimentation. Gold mining in the Amazon has resulted in mercury poisoning in ecosystems and high levels of mercury in species such as birds of prey. In Indonesia, reports have shown that Freeport-McMoRan, since 1972, has transformed Mount Ertsberg into a 600-metre hole and has released substantial amounts of toxins into local streams, up to 700,000 tonnes of waste per day, thereby destroying wetlands and aquatic life.

The Grasberg Mine at Papua, Indonesia The Grasberg Mine at Papua, Indonesia.

These are just a few instances; there can also be significant social or cultural impacts. Dam construction or irrigation projects often have a profoundly negative impact on residential communities, particularly in countries where there is little legal protection to ensure that an EIA occurs. Dam construction can lead to displacement and resettlement of people living nearby. People find it difficult to find work in the new location, and their previous livelihoods become disrupted. Some studies indicate that up to 80 million people have been displaced due to dam construction. Some of the disputed dams include Myanmar’s Myitsone Dam, Brazil’s Belo Monte Dam, China’s Three Gorges Dam, India’s Sardar Sarovar Dam, and Mozambique’s Mphanda Nkuwa Dam, among others.

Aerial view of Three Gorges Dam and Hydropower Plant - Sanxia Dam on Yangtze River in China. Aerial view of Three Gorges Dam and Hydropower Plant – Sanxia Dam on Yangtze River in China.

Identifying impacts is critical not only for obvious reasons but also to consider their global scale and implications. It is essential to balance their relative magnitude to ensure the best course of action for the proposed activity.

If you would like to read further about this, you can access the following articles Social Impacts of a Mega-Dam Project as Perceived by Local, Resettled and Displaced Communities: A Case Study of Merowe Dam, Sudan [1] and The 2019 Review of IPBES and Future Priorities: Reaching Beyond Assessment to Enhance Policy Impact [2].

References

1. Abdullah, A.-N.; Rahman, S. Social Impacts of a Mega-Dam Project as Perceived by Local, Resettled and Displaced Communities: A Case Study of Merowe Dam, Sudan. Economies 2021, 9, 140. https://doi.org/10.3390/economies9040140

2. Stevance, Anne-Sophie, et al. 2019 “The 2019 Review of IPBES and Future Priorities: Reaching Beyond Assessment to Enhance Policy Impact.” Ecosystems and People (Abingdon, England), vol. 16, no. 1, 2020, pp. 70–77, https://doi.org/10.1080/26395916.2019.1702590.

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Environmental Impact Assessment

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