Status: this preprint is open for discussion and under review for Natural Hazards and Earth System Sciences (NHESS).
Soil Liquefaction Hazards and Ecological Impacts in Coastal Wetlands of the Pisco River, Peru
Belinia Báez,Alejandra G. Martínez,Adelaida Araníbar,Erick Príncipe,and Juan Carlos Gómez
Abstract. Coastal wetlands located in seismic regions can be highly vulnerable to soil liquefaction, a phenomenon where saturated, loosely compacted soils temporarily lose strength during earthquakes. This study investigates the relationship between soil liquefaction and the dynamics of coastal wetlands along the left bank of the Pisco River in Peru, a region affected by the 2007 Pisco earthquake. Through geotechnical field tests, satellite image analysis, and local interviews, we identified that wetlands and their adjacent areas – often with shallow groundwater and sandy soils – present high susceptibility to liquefaction. Affected wetlands showed both negative impacts, such as ground subsidence and vegetation loss, and in some cases, post-seismic ecological recovery due to groundwater rise. The results confirm that even degraded or filled wetlands retain subsurface characteristics prone to liquefaction, extending risk zones up to approximately 200 meters beyond current water boundaries. These findings highlight the dual role of wetlands as both vulnerable ecosystems and natural indicators of geotechnical risk. Future research should focus on integrating wetland conservation into seismic risk management and land-use planning. Recognizing the geotechnical memory of these ecosystems is key to avoiding infrastructure damage and promoting more resilient coastal development in earthquake-prone areas.
Received: 20 Nov 2025 – Discussion started: 30 Dec 2025
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The manuscript addresses an interesting and important topic by linking soil liquefaction hazards with wetland ecology in a seismically active region. The integration of geotechnical analysis, satellite observations, and local interviews is valuable and gives a multidisciplinary perspective. The paper is generally well organized and contains useful field-based observations. However, several sections require improvement in clarity, structure, and scientific discussion before publication.
Specific Comments:
The introduction is very long and contains an excessive literature review. It will improve readability if the authors shorten some background discussions and focus more directly on the research gap and objectives.
The novelty of the study should be explained more clearly. The manuscript discusses liquefaction and wetlands, but the unique scientific contribution compared to previous studies is not sufficiently highlighted.
The methodology section needs more details regarding the DPL-to-SPT correlation procedure. The uncertainty and limitations of using equivalent SPT values should also be discussed.
The authors should explain why only 26 DPL tests and 5 test pits were considered sufficient for the study area. Some justification on spatial representativeness is needed.
The NDVI/SAVI analysis is interesting, but the attribution of vegetation increase solely to earthquake-related processes may be too strong. Other climatic or hydrological factors during 2000–2014 should also be considered.
The discussion sometimes becomes descriptive rather than analytical. More comparison with previous international studies on post-seismic wetland recovery would strengthen the scientific discussion.
The interview-based observations are valuable, but the manuscript should mention possible biases and limitations associated with local memory and perception.
The manuscript would benefit from a clearer explanation of the “200 m influence zone” and how this threshold was determined.
Several paragraphs in the Discussion section are too long. Shortening and restructuring them would improve readability.
The conclusion is good, but some statements appear repetitive. The authors may consider making the conclusions more concise and focused on the main findings.
We studied how coastal wetlands in Pisco, Peru respond to strong earthquakes that cause the ground to behave like a liquid. Combining soil tests, satellite images and local testimonies, we found that these wetlands and nearby lands are highly prone to damage, but also capable of rapid ecological recovery. Our results show that wetlands act both as fragile ecosystems and as natural warning signs, so protecting them is vital for reducing future earthquake risk.
We studied how coastal wetlands in Pisco, Peru respond to strong earthquakes that cause the...
The manuscript addresses an interesting and important topic by linking soil liquefaction hazards with wetland ecology in a seismically active region. The integration of geotechnical analysis, satellite observations, and local interviews is valuable and gives a multidisciplinary perspective. The paper is generally well organized and contains useful field-based observations. However, several sections require improvement in clarity, structure, and scientific discussion before publication.
Specific Comments: