💧 TikatuWQ: An R Package for Water Quality Assessment and Environmental Compliance in Brazil

TikatuWQ is an open-source R package designed to analyze, visualize, and report water quality data according to Brazilian environmental standards.
It implements the main indices used in the country IQA/NSFWQI and IET (Carlson and Lamparelli) and provides automated checks for CONAMA Resolution 357/2005 compliance.
The package also includes trend analysis, data validation, and automatic report generation.

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Installation (development)

To install development dependencies and check the package locally:

install.packages(c("devtools","testthat","rmarkdown","ggplot2","dplyr","tidyr",
                   "readr","lubridate","stringr","glue","scales","broom","purrr"))
devtools::load_all("tikatuwq")
devtools::check("tikatuwq")

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Basic workflow

df <- read_wq(system.file("extdata","exemplo_chamagunga.csv", package="tikatuwq")) |>
  validate_wq() |>
  iqa(na_rm = TRUE)

plot_iqa(df)

# Analytical text (rule-based)
pars <- generate_analysis(df, classe_conama = "2",
                          incluir_tendencia = TRUE,
                          parametros_tendencia = c("turbidez","od","pH"),
                          contexto = list(river="Chamagunga", period="2025-07"))
cat(paste(pars, collapse = "\n\n"))

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📚 Scientific and Institutional Context

The TikatuWQ package was developed by Vinícius Saraiva Santos (author and maintainer)
as part of the Tikatu Research Project, conducted within the Nucleus for Research in Tropical Ecosystems – NuPEcoTropic, a research group linked to the Federal University of Southern Bahia (UFSB) and coordinated by Prof. Dr. Fabrício Berton Zanchi.

This work was carried out as part of the activities of the Postgraduate Program in Biosystems (PPG Biossistemas) at UFSB, under the supervision of Prof. Dr. Fabrício Berton Zanchi.

The Tikatu Project, developed and coordinated by Vinícius Saraiva Santos, integrates research focused on environmental monitoring and modeling.

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🆕 News

🆕 What's new in v0.7.2

• Fixed CRAN incoming NOTE:
  • Removed non-standard fields (DOI, Citation) from DESCRIPTION.
  • Updated inst/CITATION to use bibentry() (replacing deprecated citEntry()).
• No functional or API changes.
• Minor documentation improvements.
• R CMD check: 0 errors | 0 warnings | 0 notes ✅

News v0.7.0

• New functions param_analysis() and param_analysis_multi():
  • Allow flexible parameter-based analyses by site or river.
  • Support cross-comparisons (multiple parameters per site or vice versa).
  • Include descriptive statistics and temporal trend detection.
• Full test coverage for new modules.
• Minor improvements to plot_trend() and plot_map() (controlled messages).
• All CRAN and devtools::check() validations passed without errors.

News v0.6.2

• Corrective update requested by CRAN.
• Fixed codoc WARNING in generate_analysis() documentation.
• Removed deprecated parameters id_cols and filter to match current signature.
• No functional or code changes made.

News v0.6.1

• Maintenance update requested by CRAN.
• Fixed relative link README-pt.md, now converted to absolute HTTPS URL.
• No functional or code changes made.

News v0.6.0

• New function plot_trend() for temporal trend analysis:
  • Trend lines per parameter/site with Theil-Sen, OLS, and LOESS methods.
  • Supports faceting by river/site and point customization.
  • Returns ggplot object ready for visualization or reports.
• Updated documentation and examples on the pkgdown site.

v0.5.1

• Fixed invalid URLs reported by CRAN (updated links and DOIs included).
• Minor documentation adjustments for R-devel compatibility.

v0.5.0

• Added internal helper functions to simplify workflow.
• New feature plot_map() for spatial visualization of sampling sites.
• Revised validation messages and standardized formatting.

v0.2.1

• generate_analysis() — automatic rule-based analytical paragraphs.
• Report template updated to include textual analysis.
• Structures added for iet_lamparelli() and nsfwqi().

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Installation via GitHub

install.packages("remotes")  # or devtools
remotes::install_github("tikatuwq/tikatuwq", dependencies = TRUE)

# stable version (by tag)
remotes::install_github("tikatuwq/[email protected]", build_vignettes = TRUE)

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CONAMA compliance (class 2)

df <- read_wq(system.file("extdata","exemplo_chamagunga.csv", package="tikatuwq"))

# Table with only violations, ready for report
conama_report(df, "2", only_violations = TRUE, pretty = TRUE)

# Short textual summary
cat(paste(conama_text(df, "2", only_violations = TRUE), collapse = "\n"))

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Main functions

• read_wq(path) — reads water quality datasets (CSV).
• validate_wq(df) — validates/normalizes columns and units.
• iqa(df, na_rm = TRUE, ...) — Water Quality Index (CETESB/NSF).
• iet_carlson(df) / iet_lamparelli(df) — Trophic State Index.
• nsfwqi(df) — NSFWQI (framework ready).
• conama_limits(class) — limits from CONAMA 357/2005 Resolution.
• conama_check(df, class) — compliance by parameter (*_ok columns).
• Visualizations: plot_iqa(), plot_series(), plot_box(), plot_heatmap(), plot_map(), plot_trend() (returns ggplot object).
• Reporting/Text: generate_analysis(), render_report().
• Example data: system.file("extdata", "exemplo_chamagunga.csv", package = "tikatuwq").

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Documentation and support

• CRAN page: https://cran.r-project.org/package=tikatuwq
• Pkgdown site: https://tikatuwq.github.io/tikatuwq/
• Issues/Suggestions: https://github.com/tikatuwq/tikatuwq/issues
• Releases: https://github.com/tikatuwq/tikatuwq/releases

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Citation

citation("tikatuwq")

How to cite

If you use tikatuwq in your research, please cite it as follows:

Santos, V. S. (2025). tikatuwq: Water Quality Assessment and Environmental Compliance in Brazil (v0.7.0). Zenodo. https://doi.org/10.5281/zenodo.17407297

BibTeX entry:

@Manual{Santos2025tikatuwq,
  title  = {tikatuwq: Water Quality Assessment and Environmental Compliance in Brazil},
  author = {Vinicius Saraiva Santos},
  year   = {2025},
  note   = {R package version 0.7.0},
  doi    = {10.5281/zenodo.17407297},
  url    = {https://github.com/tikatuwq/tikatuwq},
}