Integrating remote sensing and plant physiology to assess the effects of mining pollution in a desert ecosystem

Mining activities in arid environments pose significant risks to vegetation, biodiversity, and ecosystem stability. This study evaluates the long-term ecological effects of phosphate mining pollution on desert vegetation in Israel's Negev Desert by integrating a 36-year Landsat-based NDVI time series (1984-2020) with recent field physiological measurements and controlled greenhouse experiments. The NDVI record revealed contrasting vegetation trajectories between a polluted site and a non-polluted reference site, with a marked decline in NDVI beginning after 2013 at the polluted site. Field analyses of four native species (Phoenix dactylifera (Palm), Phragmites australis (Common reed), Atriplex halimus (Saltbush), and Sueda vera forssk.ex JFGmel (Sueda vera) demonstrated significant physiological and spectral stress under polluted conditions, with palm and Sueda vera showing the greatest pigment loss. Groundwater from the polluted spring contained elevated concentrations of arsenic (304 μg/L; ∼3× above Israeli Ministry of Health limits), boron (2069 μg/L; ∼2× above Health Canada limits), and nickel (254 μg/L; ∼13× above EPA limits). Greenhouse experiments using maize (Zea mays) and basil (Ocimum basilicum) confirmed pollution-driven stress responses, including reduced chlorophyll content, decreased stomatal conductance, and increased visible-range reflectance. While the NDVI time series provides long-term evidence of vegetation decline, the field and greenhouse datasets offer mechanistic insight into current physiological stress. Together, these findings demonstrate the cumulative ecological impact of mining-related pollution and highlight the value of integrating Landsat NDVI time series monitoring, physiological measurements, and spectroscopy to support sustainable environmental management in vulnerable arid ecosystems.