Water-Energy-Food-Nutrient-Carbon Nexus Analysis for Agronomic Systems

Provides functions for analysing Water-Energy-Food-Nutrient-Carbon (WEFNC) nexus interactions in agricultural production systems. Includes functions for computing water use efficiency (WUE), water productivity (WP), and water footprint (WF) including green, blue, and grey components following the methodology of Hoekstra et al. (2011, ISBN:9781849712798). Includes energy budgeting tools for energy use efficiency (EUE), energy return on investment (EROI), net energy (NE), and energy productivity (EP). Computes nutrient use efficiency (NUE) metrics including agronomic efficiency (AE), physiological efficiency (PE), recovery efficiency (RE), and partial factor productivity (PFP) as defined by Dobermann (2007) < https://digitalcommons.unl.edu/agronomyfacpub/316/> and Congreves et al. (2021) . Estimates carbon footprint (CF), greenhouse gas (GHG) emissions, soil organic carbon (SOC) stocks, and global warming potential (GWP) using Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6) default values (CH4 = 27, N2O = 273) as reported in Forster et al. (2021) . Computes composite Water-Energy-Food-Nutrient-Carbon (WEFNC) nexus indices, trade-off correlation matrices, and generates radar and heatmap visualizations for comparing agricultural treatments. Supports conservation agriculture (CA), irrigated and rain-fed systems, and arid and semi-arid production environments. Methods follow Lal (2004) for carbon emissions from farm operations, and Hoover et al. (2023) for water use efficiency indicators.

wefnexus

Overview

wefnexus provides a comprehensive toolkit for analyzing Water-Energy-Food-Nutrient-Carbon (WEFNC) nexus interactions in agricultural production systems. It includes 68 functions across 6 modules with a nexus integration layer.

Installation

Install from CRAN:

install.packages("wefnexus")

Modules

Module	Functions	Key Metrics
Water	11	WUE, WP, WF (green/blue/grey), CWSI, CWP, RUE, IWP, WSI
Energy	14	EUE, EROI (standard + extended), EP, EI, NER, REF, energy budget
Food	12	FPI, HI, LER, SPI, SYI, nutritional yield, BCR
Nutrient	11	AE, PE, RE, PFP, IUE, NHI, N surplus, SNI
Carbon	10	CF, GHG, SOC, GWP (IPCC AR6), CEI, NECB
Nexus	10	Composite index, trade-off matrix, sensitivity, radar, heatmap

Quick Example

library(wefnexus)
data(arid_pulse_nexus)
d <- arid_pulse_nexus

# Compute EROI with extended analysis
e_out <- d$energy_output_grain + d$energy_output_straw
eroi(energy_out = e_out, energy_in = d$energy_input)

# Full nexus summary
nexus_summary(
  yield = d$grain_yield,
  water_consumed = d$total_water,
  energy_input = d$energy_input,
  energy_output = e_out,
  n_applied = d$n_applied,
  n_uptake = d$n_uptake,
  carbon_emission = d$ghg_emission,
  treatment_names = d$treatment
)

Key Features

68 functions across 6 integrated modules
EROI with standard, extended, and Net Energy Ratio analysis
IPCC AR6 GWP defaults: CH4 = 27, N2O = 273 (100-yr horizon)
Nutritional yield analysis (protein, Fe, Zn, persons fed)
Nexus sensitivity analysis for weight perturbation assessment
Conservation agriculture focus (CT/ZT/PB comparisons)
Arid and semi-arid environment emphasis
CRAN-ready: verbose parameter, proper documentation
Base R graphics: zero external plotting dependencies

Citation

Rolaniya, L.K., Poonia, H., Jat, R.L., Punia, M. & Choudhary, R.R. (2026).
wefnexus: Water-Energy-Food-Nutrient-Carbon Nexus Analysis for Agronomic
Systems. R package version 1.0.0. https://CRAN.R-project.org/package=wefnexus