Tracking five decades (1972–2024) of spatio-temporal dynamics and hotspots of Prosopis juliflora in Keoladeo national park, a World Heritage Site

Assessing the spatial distribution and composition of vegetation is key to biodiversity assessment and conservation efforts. This study examines the changes in Keoladeo National Park (KNP) over the last five decades due to the invasion of Prosopis juliflora. Prosopis deliberately planted in the KNP during the 1960s and 1970s has spread at an alarming rate and significantly affected native terrestrial and wetland species. Emerging hot spot analysis, an advanced space–time pattern mining technique was used to analyze the spatio-temporal trends of invasion by Prosopis juliflora. The annual rate of spread was estimated to be 3.31% over the last five decades (1972–2024). A slight decrease in the distribution of P. juliflora from 2021 indicates that management's continued efforts are having a positive effect. Grasslands decreased by 51%, while P. juliflora increased by 82%, indicating a long-term trend of invasive species encroachment. This study identified different categories of spatiotemporal trends in invasion hotspots. Oscillating hot spots with fluctuating levels of P. juliflora coverage contributed the most (82.73%), followed by persistent hot spots (6.55%) and new hot spots (4.83%). The dominance of oscillating hotspots suggests that reactive management strategies in KNP may be effective in mitigating the spread of P. juliflora. The current work highlights the application of multi-temporal remote sensing data and geospatial techniques to monitor the spread of invasive species and to identify sites where more effective management is needed.