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Abstract Mangrove soils provide many important ecosystem services such as carbon sequestration, yet they are vulnerable to the negative impacts brought on by anthropogenic activities. Research in recent decades has shown a progressive loss of blue carbon in mangrove forests as they are converted to aquaculture, agriculture, and urban development. We seek to study the relationship between human population density and soil carbon stocks in urban mangrove forests to quantify their role in the global carbon budget. To this end, we conducted a global analysis, collecting mangrove soil carbon data from previous studies and calculating population density for each study location utilizing a recent database from the European Commission. Results indicate population density has a negative association with mangrove soil carbon stocks. When human population density reaches 300 people km−2, which is defined as ‘urban domains’ in the European Commission database, mangrove soil carbon is estimated to be lower than isolated mangrove forests by 37%. Nonetheless, after accounting for climatic factors in the model, we see the negative relationship between population density and soil carbon is reduced and is even non-significant in mixed effects models. This suggests population density is not a good measure for the direct effects of humans on mangrove ecosystems and further implies mangrove ecosystems in close proximity to very high population density can still possess valuable carbon stocks. Our work provides a better understanding of how soil carbon stocks in existing mangrove forests correlate with different levels of population density, underscores the importance of protecting existing mangroves and especially those in areas with high human population density, and calls for further studies on the association between human activities and mangrove forest carbon stocks.
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This content will become publicly available on January 1, 2026
A “Golden Moment” for Soils and Society Presents Challenges and Opportunities for Soil Science
We appear to be at a shining moment for interactions between soils and society. Popular interest in soils has increased along with interests in urban gardening, carbon sequestration, recognition of the vast biodiversity in soils, and the realisation that soils are a finite resource whose degradation has serious consequences. This increase in interest creates both opportunities and challenges for soil science. While there is great potential for increasing the diversity of people involved with soil science, key scientific and communication challenges need to be addressed for interactions between soils and society to be useful and productive. Here, I present case study issues on the mechanisms and limitations of carbon sequestration in soils and the need to restore and/or create new soils for specific uses, including urban agriculture and green infrastructure, to illustrate the opportunities and challenges associated with new societal interest in soil science. Addressing these issues requires advances in both basic and applied science, new participatory approaches to the design, execution, and interpretation of research, collaboration with multiple disciplines, including the social sciences, and improvements in the two‐way flow of information between science and society. Careful attention to these issues will attract new people to soil science, advance awareness of the importance of and threats to soils across the globe, and produce improvements in the quality of life for diverse human populations.
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- PAR ID:
- 10565176
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- European Journal of Soil Science
- Volume:
- 76
- Issue:
- 1
- ISSN:
- 1351-0754
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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