Abstract
The southern Patagonian steppe grasslands are fundamental ecosystems for biodiversity conservation and the maintenance of productive activities, although they are highly sensitive to anthropogenic disturbances. This study assessed vegetation cover recovery along a section of the Dungeness–Daniel Este 8" hydrocarbon pipeline, Magallanes Region (Chile), to determine the ecological resilience of coironal grassland nearly three decades after its construction.
Vegetation characterization was performed using 72 modified Parker plots of 1 m² (2 × 0.5 m). In each plot, the presence and cover of all vascular and cryptogamic species were recorded, together with litter, standing dead vegetation, bare soil, stones, and feces. Thirty-six plots were placed randomly along the pipeline axis (flow line), and thirty-six in a non-intervened reference area located 20–25 m away but under grazing use. Species richness, vegetation cover, bare soil, and diversity indices (Shannon and Pielou) were calculated. Data were analyzed using non-parametric tests (Kruskal–Wallis) and multivariate analyses (PCA, ANOSIM, and SIMPER).
A total of 66 species were identified, 81.8% of which were native. Vegetation cover reached 67.8% along the pipeline and 73.9% in the reference area, exceeding the 60% threshold required by the Environmental Qualification Resolution. No significant differences in richness or diversity were detected, indicating a comparable floristic structure. Dominant species Festuca gracillima and Baccharis magellanica accounted for 40% of total dissimilarity, together with colonizing species such as Acaena magellanica and Rumex acetosella, indicating an advanced stage of secondary succession. The occurrence of Chloraea magellanica, a rare orchid with restricted distribution, highlights the presence of functional microhabitats and recovering mycorrhizal associations.
Results demonstrate that, despite arid conditions and grazing pressure, vegetation has re-established its structure and function through passive restoration processes. This case provides empirical evidence that underground pipelines, when maintaining ecological connectivity, can be integrated into the landscape without significant biodiversity loss.
References
Acharya, B.S., Rasmussen, J., & Eriksen, J. (2012). Grassland carbon sequestration and emissions following cultivation in a mixed crop rotation. Agriculture, Ecosystems & Environment, 153, 33–39. https://doi.org/10.1016/j.agee.2012.03.008
Avirmed, O.I., Burke, C., Mobley, M.L., Lauenroth, W.K., & Schlaepfer, D.R. (2014). Natural recovery of soil organic matter in 30–90-year-old abandoned oil and gas wells in sagebrush steppe. Ecosphere, 5, 24. https://doi.org/10.1890/ES13-00272.1
Bardgett, R.D., Bullock, J.M., Lavorel, S., Manning, P., Schaffner, U., Ostle, N., Chomel, M., Durigan, G., Fry, E.L., Johnson, D., Lavallee, J.M., Le Provost, G., Luo, S., Png, K., Sankaran, M., Hou, X., Zhou, H., Ma, L., Ren, W., & Li, Y. (2021). Combatting global grassland degradation. Nature Reviews Earth & Environment, 2(10), 720–735. https://doi.org/10.1038/s43017-021-00207-2
Bengtsson, J., Bullock, J.M., Egoh, B., Everson, C., Everson, T., O'Connor, T., O'Farrell, P.J., Smith, H.G., & Lindborg, R. (2019). Grasslands—more important for ecosystem services than you might think. Ecosphere, 10(2), e02582. https://doi.org/10.1002/ecs2.2582
Brehm, T., & Culman, S. (2022). Efectos de la instalación de tuberías en suelos y plantas: una revisión y síntesis cuantitativa. Agrosistemas, Geociencias y Medio Ambiente, 5, e20312. https://doi.org/10.1002/agg2.20312
CIREN (2010). Determinación de la erosión actual y potencial de los suelos de Chile. Región de Magallanes y de la Antártica Chilena: Síntesis de resultados (Publicación N.º 153). Centro de Información de Recursos Naturales.
Clarke, K.R. (1993). Non-parametric multivariate analyses of changes in community structure. Australian Journal of Ecology, 18(1), 117–143. https://doi.org/10.1111/j.1442-9993.1993.tb00438.x
Clarke, K.R., & Green, R.H. (1988). Statistical design and analysis for a "biological effects" study. Marine Ecology Progress Series, 46, 213–226. https://doi.org/10.3354/meps046213
Correa, M.N. (1969, 1971, 1978, 1984, 1985, 1988, 1999). Flora Patagónica I-VIII. Colección Científica INTA.
Di Rienzo, J.A., Casanoves, F., Balzarini, M.G., González, L., Tablada, M., & Robledo, C.W. (2011). InfoStat versión 2016. Grupo InfoStat, FCA, Universidad Nacional de Córdoba. http://www.infostat.com.ar
Domínguez, E. (2023). Dinámica de la cubierta vegetal en pastizales nativos de la estepa magallánica perturbados por la construcción de un ducto de hidrocarburos, Chile. Anales del Instituto de la Patagonia, 51(3), e202351003. https://doi.org/10.22352/aip202351003
Golluscio, R.A., Cavagnaro, F.P., & Valenta, M.D. (2011). Arbustos de la estepa patagónica: ¿Adaptados a tolerar la sequía o el pastoreo? Ecología Austral, 21(1), 61–70.
González, A. (2000). Evaluación del recurso vegetacional en la cuenca del río Budi, situación actual y propuestas de manejo [Tesis de licenciatura, Universidad Católica de Temuco].
Haddad, N.M., Bowne, D.R., Cunningham, A., Danielson, B.J., Levey, D.J., Sargent, S., & Spira, T. (2003). Corridor use by diverse taxa. Ecology, 84(3), 609–615. https://doi.org/10.1890/0012-9658(2003)084[0609:CUBDT]2.0.CO;2
Hammer, Ø., Harper, D.A.T., & Ryan, P.D. (2001). PAST: Paleontological statistics software package for education and data analysis. Palaeontologia Electronica, 4(1), 1–9.
Han, X., Ochoa-Hueso, R., Ding, Y., Li, X., Jin, K., van der Putten, W.H., & Struik, P.C. (2025). Grazing intensity by sheep affects spatial diversity in botanical composition of Inner Mongolian grassland. Agriculture, Ecosystems & Environment, 378, 109311. https://doi.org/10.1016/j.agee.2024.109311
Herrera, H., Sanhueza, T., da Silva Valadares, R.B., Matus, F., Pereira, G., Atala, C., Mora, M. de la L., & Arriagada, C. (2022). Diversity of root-associated fungi of the terrestrial orchids Gavilea lutea and Chloraea collicensis in a temperate forest soil of south-central Chile. Journal of Fungi, 8(8), 794. https://doi.org/10.3390/jof8080794
Instituto de Investigaciones Agropecuarias (INIA). (1982). Zonificación agroclimática de la Región de Magallanes y Antártica Chilena. Ministerio de Agricultura, Chile.
Kowaljow, E., & Rostagno, C. (2013). Soil evolution along restoration chronosequences of semiarid steppes in Patagonia: Influence of plant cover and litter. Catena, 104, 1–9. https://doi.org/10.1016/j.catena.2012.10.014
Liu, P., Chi, Y., Huang, Z., Zhong, D., & Zhou, L. (2024). Multidimensional response of China's grassland stability to drought. Global Ecology and Conservation, 52, e02961. https://doi.org/10.1016/j.gecco.2024.e02961
Naeth, M.A., Wilkinson, S.R., Locky, D.A., Bryks, C.L., Low, C.H., & Nannt, M.R. (2020). Pipeline impacts and recovery of dry mixed-grass prairie soil and plant communities. Rangeland Ecology & Management, 73(5), 619–628. https://doi.org/10.1016/j.rama.2020.03.004
Niu, W., Liu, P., Han, X., Chi, Y., & Zhou, L. (2025). Global effects of livestock grazing on ecosystem functions. Agriculture, Ecosystems & Environment, 378, 109296. https://doi.org/10.1016/j.agee.2024.109296
Oliva, G., Ferrante, D., Paredes, P., Humano, G., & Cesa, G. (2016). A conceptual model for changes in floristic diversity under grazing in semi-arid Patagonia using the State and Transition framework. Journal of Arid Environments, 127, 120–127. https://doi.org/10.1016/j.jaridenv.2015.11.002
Olson, E.R., & Doherty, J.M. (2012). The legacy of pipeline installation on the soil and vegetation of southeast Wisconsin wetlands. Ecological Engineering, 39, 53–62. https://doi.org/10.1016/j.ecoleng.2011.11.003
Prach, K., Sebelíková, L., Rehounková, K., & del Moral, R. (2020). Possibilities and limitations of passive restoration of heavily disturbed sites. Landscape Research, 45(2), 247–253. https://doi.org/10.1080/01426397.2019.1593335
Rodríguez, R., Marticorena, C., Alarcón, D., Baeza, C., Cavieres, L., Finot, V.L., Fuentes, N., Kiessling, A., Mihoc, M., Pauchard, A., Ruiz, E., Sanchez, P., & Marticorena, A. (2018). Catálogo de las plantas vasculares de Chile. Gayana Botánica, 75(1), 1–430. https://doi.org/10.4067/S0717-66432018000100001
Santibáñez, F., Santibáñez, P., Caroca, C., & González, P. (2017). Atlas agroclimático de Chile. Estado actual y tendencias del clima. Tomo VI: Regiones de Aysén y Magallanes. Universidad de Chile. http://www.agrimed.cl/atlas/tomo6.html
Servicio de Evaluación Ambiental (SEA). (2021). Guía para la descripción de proyectos de desarrollo minero de petróleo y gas en el SEIA (2.ª ed.). https://www.sea.gob.cl/sites/default/files/imce/archivos/2021/03/12/guia_dp_petroleo_y_gas_en_el_seia_compressed.pdf
Smith, W.K., Dannenberg, M.P., Yan, D., et al. (2019). Remote sensing of dryland ecosystem structure and function: Progress, challenges, and opportunities. Remote Sensing of Environment, 233, 111401. https://doi.org/10.1016/j.rse.2019.111401
Török, P., Brudvig, L.A., Kollmann, J., Price, J.N., & Tóthmérész, B. (2021). The present and future of grassland restoration. Restoration Ecology, 29(S1), 1–6. https://doi.org/10.1111/rec.13378
UNCCD (2022). The Global Land Outlook (2nd ed.). United Nations Convention to Combat Desertification. https://www.unccd.int/resources/global-land-outlook
Van der Maarel, E. (2007). Transformation of cover-abundance values for appropriate numerical treatment Alternatives to the proposals by Podani. Journal of Vegetation Science, 18(5), 767-770.
Wu, B., Smith, W.K., & Zeng, H. (2024). Dryland dynamics and driving forces. In B. Fu & M. Stafford-Smith (Eds.), Dryland social-ecological systems in changing environments (pp. 25–52). Springer. https://doi.org/10.1007/978-981-99-9375-8_2
Xiao, J., Shi, P., Wang, Y., & Yang, L. (2016). The vegetation recovery pattern and affecting factors after pipeline disturbance in Northwest China. Journal for Nature Conservation, 29, 114–122. https://doi.org/10.1016/j.jnc.2015.12.009
Zhao, F., Wang, N., Liu, J., & Zhou, Z. (2022). Effects of vegetation type and topography on vegetation restoration after pipeline construction in the Northern Shaanxi Loess Plateau, China. Ecological Research, 38(1), 177–187. https://doi.org/10.1111/1440-1703.12392
Zhao, X., Li, F., Yuan, Y., Ari, G., Yan, Y., Zhang, Q., Olhnuud, A., & Liu, P. (2025). Wind farms reduce grassland plant community diversity and lead to plant community convergence. BMC Ecology and Evolution, 25(1), 10. https://doi.org/10.1186/s12862-025-02350-6
Zhu, K., Song, Y., Lesage, J.-C., et al. (2024). Cambios rápidos en las comunidades de pastizales impulsados por el cambio climático. Nature Ecology & Evolution, 8(10), 2252–2264. https://doi.org/10.1038/s41559-024-02552-z
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.