Decoding carbon, water, and energy exchange driven by agricultural and horticultural intensification in semi-arid ecosystem of India.

Terrestrial ecosystems play a vital role in sequestering carbon dioxide (CO2); however, growing both agri-horticultural intensifications can influence CO2 sequestration potential. This study was conducted in an agri-horticultural-intensive ecosystem of Central India to investigate the net ecosystem exchange (NEE) of CO2, water (H2O), and energy fluxes and assess the influence of meteorological factors using the eddy covariance datasets acquired from January to June 2024. The highest monthly mean diurnal CO2 flux was recorded in January (-7.98 µmol m-2 s-1), and the lowest was in June (-3.03 µmol m-2 s-1), resulting in a cumulative CO2 uptake of -94.5 g C m-2 half-year-1. Evapotranspiration (ET) over the January-to-June period was recorded at 273.3 mm, with sensible heat (H) dominating over latent heat (LE) flux, indicating water-stressed semi-arid ecosystem. Over the 6-month period, the ecosystem exhibited a net ecosystem exchange (NEE) of -177.59 g C m-2 half-year-1, a gross primary productivity (GPP) of 567.13 g C m-2 half-year-1, and an ecosystem respiration (Reco) of 389.54 g C m-2 half-year-1. Despite agri-horticultural intensification, the ecosystem functioned as a strong sink for atmospheric CO2. The findings provide critical insights into carbon, water, and energy exchanges in agri-horticultural landscapes and are essential for understanding the market-driven agri-horticultural intensification and developing sustainable land restoration strategies to address groundwater depletion, climate vulnerability and ecosystem functioning.