{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:50:39Z","timestamp":1760147439494,"version":"build-2065373602"},"reference-count":61,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,3]],"date-time":"2023-02-03T00:00:00Z","timestamp":1675382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Institute for Humanity and Nature","award":["RIHN 14200102"],"award-info":[{"award-number":["RIHN 14200102"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Potentially toxic elements (PTEs) from natural and anthropogenic activities threaten the environment and human health. The associations of PTEs with natural hazards can be powerful and prominent mechanisms to release PTEs, considerably hastening their multiple contaminations and widespread distribution. This study primarily aimed to investigate the enhanced potential distribution of PTE contaminations (arsenic, lead, and mercury) from coexisting gold mining operations combined with massive riverbank erosion in Indonesia from 2002 to 2022, where soil and water are highly contaminated naturally, using PlanetScope smallsat constellations, Google Earth imagery, and hydrographic datasets. According to the findings, increased barren extents were found because of mining deposits and road network developments. Enhanced natural and anthropogenic PTE runoffs would be transported across two different sub-basins, affecting broader parts of the Bone River. Between 2002 and 2022, 139.3% of river expansion was identified, eroding a maximum of 3,436,139.4 m3 of contaminated soil. Particularly land surfaces were repeatedly transformed from rivers to agricultural lands in the low Bone River, possibly contaminated by fertilizer spills. The combination of PTE potentials from different sources would further exacerbate the contamination level at an estuary. These findings are expected to aid in the timely monitoring of and assuming volumes, rates, and distribution of PTEs from various natural and anthropogenic activities and alert PTE contamination risks to ecosystems and human health. Future work in this area should aim to investigate contamination levels at the estuary, where contaminated materials from both natural and anthropogenic activities are accumulated.<\/jats:p>","DOI":"10.3390\/rs15030861","type":"journal-article","created":{"date-parts":[[2023,2,6]],"date-time":"2023-02-06T05:29:05Z","timestamp":1675661345000},"page":"861","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Distribution of Enhanced Potentially Toxic Element Contaminations Due to Natural and Coexisting Gold Mining Activities Using Planet Smallsat Constellations"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7137-7815","authenticated-orcid":false,"given":"Satomi","family":"Kimijima","sequence":"first","affiliation":[{"name":"Research Institute for Humanity and Nature, Kyoto 603-8047, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0625-762X","authenticated-orcid":false,"given":"Masahiko","family":"Nagai","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology for Innovation, Yamaguchi University, Ube 755-8611, Japan"},{"name":"Center for Research and Application of Satellite Remote Sensing, Yamaguchi University, Ube 755-8611, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8188-6979","authenticated-orcid":false,"given":"Masayuki","family":"Sakakibara","sequence":"additional","affiliation":[{"name":"Research Institute for Humanity and Nature, Kyoto 603-8047, Japan"},{"name":"Graduate School of Science and Engineering, Ehime University, Matsuyama 790-8577, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,3]]},"reference":[{"key":"ref_1","first-page":"17","article-title":"Heavy Metal Contamination of Soils: Sources, Indicators, and Assessment","volume":"9","author":"He","year":"2015","journal-title":"J. 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