Evidence map›Paper›PMID 39841654›Full record

ArticlePloS one2025

AI enabled, mobile soil pH classification with colorimetric paper sensors for sustainable agriculture.

Ademir Ferreira da Silva, Ricardo Luis Ohta, Jaione Tirapu Azpiroz, Matheus Esteves Ferreira, Daniel Vitor Marçal, André Botelho, Tulio Coppola, Allysson Flavio Melo de Oliveira, Murilo Bettarello, Lauren Schneider and 6 more

Abstract read
In one paragraph

Article in PloS one, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Review
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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

16 authors.

Ademir Ferreira da SilvaIBM Research, Rio de Janeiro, Brazil.
Ricardo Luis OhtaIBM Research, São Paulo, Brazil.
Jaione Tirapu AzpirozIBM Research, Rio de Janeiro, Brazil.ORCID 0000-0002-4151-7722
Matheus Esteves FerreiraIBM Research, Rio de Janeiro, Brazil.
Daniel Vitor MarçalIBM Research, Rio de Janeiro, Brazil.
André BotelhoIBM Research, São Paulo, Brazil.
Tulio CoppolaIBM Research, São Paulo, Brazil.
Allysson Flavio Melo de OliveiraIBM Research, São Paulo, Brazil.
Murilo BettarelloEnveritas, New York, NY, United States of America.
Lauren SchneiderEnveritas, New York, NY, United States of America.
Rodrigo VilaçaCSEM Brasil, Belo Horizonte, Brazil.
Noorunisha AbdoolOmnia Fertilizers, Bryanston, South Africa.
Vanderlei JuniorIntegrada, Londrina, Brazil.
Wellington FurlanetiIntegrada, Londrina, Brazil.
Pedro Augusto MalangaIntegrada, Londrina, Brazil.
Mathias SteinerIBM Research, Rio de Janeiro, Brazil.ORCID 0000-0003-1528-9292

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

For optimizing production yield while limiting negative environmental impact, sustainable agriculture benefits from real-time, on-the-spot chemical analysis of soil at low cost. Colorimetric paper sensors are ideal candidates, however, their automated readout and analysis in the field is needed. Using mobile technology for paper sensor readout could, in principle, enable the application of machine-learning models for transforming colorimetric data into threshold-based classes that represent chemical concentration. Such a classification method could provide a basis for soil management decisions where high-resolution lab analysis is not required or available. In tropical regions, where reliable soil data is difficult to acquire, this approach would be particularly useful. Here, we report a mobile chemical analysis system based on colorimetric paper sensors that operates under tropical field conditions. A standard smartphone equipped with a dedicated software application automatically classifies the paper sensor results into three classes-low, medium, or high soil pH-which provides a basis for soil correction. The classification task is performed by a machine-learning model which was trained on the colorimetric pH indicators deployed on the paper sensor. By mapping topsoil pH on a test site with an area of 9 hectares, the mobile system was benchmarked in the field against standard soil lab analysis. The mobile system has correctly classified soil pH in 97% of test cases, while reducing the analysis turnaround time from days (soil lab) to minutes (mobile). By performing on-the-spot analyses using the mobile system in the field, a 9-fold increase of spatial resolution reveals pH-variations not detectable in the standard compound mapping mode of lab analysis. We discuss how the mobile analysis can support smallholder farmers and enable sustainable agriculture practices by avoiding excessive soil correction. The system can be extended to perform multi-parameter chemical tests of soil nutrients for applications in environmental monitoring at marginal manufacturing cost.

Indexed as

AgricultureColorimetrySoilHydrogen-Ion ConcentrationMachine LearningPaperSmartphoneSoil

Identifiers

PMID39841654
PMCPMC11753690

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.