Spatial Assessment of Social and Environmental Vulnerabilities by Landslides in Hoa An Region, Non Nuoc Cao Bang UNESCO Global Geopark, Vietnam
Main Article Content
Abstract
This study develops a GIS-based framework to quantify socio-environmental vulnerability and examine its spatial correspondence with independently derived landslide density (LSD) in Hoa An District, within the Non Nuoc Cao Bang UNESCO Global Geopark, Vietnam. Eight social and environmental indicators were integrated using Principal Component Analysis, explaining 69.80% and 73.39% of variance, respectively, and K-means clustering identified four distinct vulnerability typologies. Landslide density, derived from a validated multi-temporal inventory using kernel density estimation, was used as an independent descriptor of past landslide activity. Results reveal a non-linear relationship between vulnerability and landslide distribution: compound vulnerability hotspots (34.01% of the area) exhibit the highest mean LSD (6.42 events/km²) and largest proportion of high-density zones (35.06%), while transitional areas show localized but elevated landslide concentrations despite moderate vulnerability, indicating the influence of unmodeled geomorphic controls. These findings demonstrate that vulnerability does not directly control landslide occurrence but modulates its spatial concentration through interactions between environmental degradation, human pressure, and terrain conditions, providing a transferable framework for identifying areas prone to disproportionate landslide impacts.
Keywords:
Principal Component Analysis, K-means clustering, environmental vulnerability, social vulnerability, landslides, UNESCO Global Geopark.
References
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[3] C. Idukunda, C. Michellier, F. D. Longueville, E. Twarabamenye, S. Henry, Assessing Community Vulnerability to Landslide and Flood in Northwestern Rwanda, International Journal of Disaster Risk Reduction, Vol. 123, 2025,
pp. 105329, https://doi.org/10.1016/j.ijdrr.2025.105329.
[4] H. Lee et al., Synthesis Report of the IPCC Sixth Assessment Report (AR6), Longer Report, IPCC, Intergovernmental Panel on Climate Change (IPCC), 2023.
[5] D. Amaratunga et al., United Nations Office for Disaster Risk Reduction Regional Assessment Report on Disaster Risk Reduction 2023: Europe and Central Asia, 2023.
[6] UNDRR 2017, The Sendai Framework Terminology on Disaster Risk Reduction, Vulnerability, [Online] Available: https://www.undrr.org/terminology/vulnerability (accessed on: September 1st, 2025).
[7] C. Idukunda, C. Michellier, F. D. Longueville, E. Twarabamenye, S. Henry, Assessing Community Vulnerability to Landslide and Flood in Northwestern Rwanda, International Journal of Disaster Risk Reduction, Vol. 123, 2025,
pp. 105329, https://doi.org/10.1016/j.ijdrr.2025.105329.
[8] N. T. Kien, V. T. H. Lien, P. L. H. Linh, N. Q. Thanh, Landslide Susceptibility Mapping Based on the Combination of Bivariate Statistics and Modified Analytic Hierarchy Process Methods: A Case Study of Tinh Tuc Town, Nguyen Binh District, Cao Bang Province, Vietnam, Journal of Disaster Research, Vol. 16, No. 4, 2021,
pp. 521-528, https://doi.org/10.20965/jdr.2021.p0521.
[9] N. T. T. Pham, D. Nong, A. R. Sathyan, M. Garschagen, Vulnerability Assessment of Households to Flash Floods and Landslides in the Poor Upland Regions of Vietnam, Climate Risk Management, Vol. 28, 2020, pp. 100215, https://doi.org/10.1016/j.crm.2020.100215.
[10] E. Tate, S. Rufat, M. A. Rahman, S. Hoover, Profiles of Social Vulnerability for Flood Risk Reduction, International Journal of Disaster Risk Reduction, Col. 118, 2025, pp. 105250, https://doi.org/10.1016/j.ijdrr.2025.105250.
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[12] E. E. Koks, B. Jongman, T. G. Husby, W. J. Botzen, Combining Hazard, Exposure and Social Vulnerability to Provide Lessons for Flood Risk Management, Environmental Science & policy, Vol. 47, 2015, pp. 42-52, https://doi.org/10.1016/j.envsci.2014.10.013.
[13] Cao Bang Provincial Statistics Office, 2021. Complete results of the 2019 Population and Housing Census in Cao Bang Province, Cao Bang Provincial Statistics Office, 2021, [Online], Available:dhttps://thongkecaobang.gso.gov.vn (accessed on: September 1st, 2025).
[14] H. D. Vu, N. T. P. Nguyen, Y. T. H. Ngo, T. D. Le, Geotourism Current State and Future Prospects: A Case Study in the Cao Bang UNESCO Global Geopark, Vietnam, GeoJournal of Tourism and Geosites, Vol. 43, No. 3, 2022, pp. 1063-1070, https://doi.org/10.30892/gtg.43327-921.
[15] N. J. M. Rodríguez, J. Vega, O. B. Zanabria, J. D. G. Ruiz, S. Botero, Towards an Understanding of Landslide Risk Assessment and its Economic Losses: A Scientometric Analysis, Landslides, Vol. 21, No. 8, 2024, pp. 1865-1881, https://doi.org/10.1007/s10346-024-02272-2.
[16] S. L. Cutter, The Vulnerability of Science and the Science of Vulnerability, Annals of the Association of American Geographers, Vol. 93, No. 1, 2023, pp. 1-12,
https://doi.org/10.1111/1467-8306.93101.
[17] J. Birkmann, Measuring Vulnerability to Promote Disaster-resilient Societies: Conceptual Frameworks and Definitions, Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies, Vol. 1, No. 9, 2006, pp. 3-7.
[18] G. Tóth, T. Hermann, G. Szatmári, L. Pásztor, Maps of Heavy Metals in the Soils of the European Union and Proposed Priority Areas for Detailed Assessment, Science of the Total Environment, Vol. 565, 2016, pp. 1054-1062, https://doi.org/10.1016/j.scitotenv.2016.05.115.
[19] P. I. Gomes, U. Aththanayake, W. Deng, A. Li, W. Zhao, T. Jayathilaka, Ecological Fragmentation Two Years after a Major Landslide: Correlations between Vegetation Indices and Geo-Environmental Factors, Ecological Engineering, Vol. 153, 2020, pp. 105914, https://doi.org/10.1016/j.ecoleng.2020.105914.
[20] A. L. Handwerger, E. J. Fielding, S. S. Sangha, and D. P. Bekaert, Landslide Sensitivity and Response to Precipitation Changes in Wet and Dry Climates, Geophysical Research Letters, Vol. 49, No. 13, 2022, pp. e2022GL099499, https://doi.org/10.1029/2022GL099499.
[21] C. J. V. Westen, E. Castellanos, S. L. Kuriakose, Spatial Data for Landslide Susceptibility, Hazard, and Vulnerability Assessment: An Overview, Engineering Geology, Vol. 102, No. 3-4, 2008,
pp. 112-131, https://doi.org/10.1016/j.enggeo.2008.03.010.
[22] I. T. Jolliffe, J. Cadima, Principal Component Analysis: A Review and Recent Developments, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 374, No. 2065, 2016, pp. 20150202, https://doi.org/10.1098/rsta.2015.0202.
[23] P. J. Rousseeuw, Silhouettes: a Graphical Aid to the Interpretation and Validation of Cluster Analysis, Journal of Computational and Applied Mathematics, Vol. 20, 1987, pp. 53-65, https://doi.org/10.1016/0377-0427(87)90125-7.