Passive acoustic sampling data of the Colección de Sonidos Ambientales Mauricio Álvarez-Rebolledo - Instituto Humboldt (IAvH-CSA) during 2018 and 2019 in Colombia.

We present the dataset of passive acoustic sampling events deposited in the Colección de Sonidos Ambientales Mauricio Álvarez-Rebolledo at the Humboldt Institute (IAvH-CSA) during the years 2018-2019. The acoustic sampling events were generated from different projects, including Colombia Bio, Santander Bio, Boyacá Bio, Lisama, Riqueza Natural, and occasional events collected during this time. In total, 44,704 sampling events are deposited in the collection, corresponding to 1 minute of automatic recording sampled at a 44.1 kHz sampling rate and 16-bit resolution. The recording schedules correspond to 1 minute every 5, 10, or 30 min throughout the day, during 1 to 20 sampling days, across 79 localities in Colombia. The geographical coverage includes the departments of Bolívar, Boyacá, Caquetá, Cundinamarca, Meta, Santander, and Sucre. The present information was collected within the framework of the passive monitoring methodology established by the Humboldt Institute .

Listening to cities during the COVID-19 lockdown: How do human activities and urbanization impact soundscapes in Colombia?

Noise is one of the fastest growing and most ubiquitous type of environmental pollution, with prevalence in cities. The COVID-19 confinement in 2020 in Colombia led to a reduction in human activities and their associated noise. We used this unique opportunity to measure the impacts of noise on urban soundscapes, and explore the effects of urbanization intensity independently of human activity. We launched a community science initiative inviting participants to collect audio recordings from their windows using smartphones. Recordings were taken during severe mobility restrictions (April), and during a period of lightened restrictions (May-June). From the data collected, we measured changes in sound pressure levels (SPL), acoustic structure (soundscape spectro-temporal characteristics), and human perception between the two periods. A 12% increase in human activities had a detectable acoustic footprint, with a significant increase of SPL (2.15 dB, 128% increase), a shift towards dominance of low-frequency broadband signals, and a perceived dominance of human-made over wildlife sounds. Measured changes in SPL and acoustic structure were directly proportional to urbanization; however, perception of these changes was not. This gap may be associated with a masking effect generated by noise or a disconnect of humans from nature in large cities. The mobility restrictions created a chance to better understand the impacts of urbanization and human activities on the soundscape, while raising public awareness regarding noise pollution effects on people and wildlife. Information analyzed here might serve in urban planning in developing countries where urban expansion is occurring in a rapid, unplanned fashion.