LUCKNOW A study by scientists at the CSIR-National Botanical Research Institute (NBRI) has exposed severe ecological degradation along the Gomti river, revealing that over a third of its riparian corridors are in urgent need of restoration. Driven by human activity and urbanisation, the riverbanks are suffering from declining tree cover, escalating soil erosion and the gradual disappearance of native flora.
To combat the degradation, the scientists deployed an Integrated Spatial Decision-Support Framework — a smart map-making system to zero in on which parts of the river require immediate attention. Using satellite images, the team measured various factors, including how green the land looked, how hot the ground was, what the soil was made of and how much of the land had been paved over.
They combined all of this information into a single score for every patch of land along the river, called the Composite Restoration Index (CRI). A high CRI score meant the area required greater restoration attention, while a low score meant it was in comparatively better ecological condition.
The results paint a concerning picture for Lucknow’s primary water body. Approximately 36% of the land along the Gomti scored in the ‘high’ or ‘very high’ restoration priority categories. Highly degraded zones include the Kakrabad Bridge, Chandiyamau, Khiron, Churheya and Tikraghat.
These areas showed very little plant life, high ground temperatures and soil that had lost much of its ecological quality. In short, the scientists said these stretches showed clear signs of ecological stress.
The scientists then visited different spots along the river to check if the satellite data matched what they observed on the ground, and they found that the field observations broadly supported the satellite-based results. In places with high restoration priority scores, they found fewer native plants and more invasive species – plants like carrot grass and lantana that spread aggressively and can affect local biodiversity.
Ground surveys reinforce this prioritisation: species richness declined from 21 to 14 species per plot and invasive dominance increased in high-CRI zones. At the same time, plots with higher native richness and greater canopy cover exhibited significantly lower land-surface temperature (by 4°C) than low-diversity, degraded plots.
“This pattern reflects the well-documented cooling effect of diverse, structurally complex vegetation through shading and evapotranspiration. Accordingly, low-CRI reaches that are already providing a measurable cooling benefit to adjacent neighborhoods should be safeguarded via zoning and incentive schemes. Embedding these priorities in Lucknow’s Smart City and river-rejuvenation plans could generate co-benefits that range from flood-peak attenuation to enhanced recreational space,” said NBRI director Ajit Shasany.
Dibyendu Adhikari, senior principal scientist and one of the researchers involved in the study, said this tool can help city planners know where to plant trees, restore soil and remove invasive plants first — instead of relying only on general estimates. “The whole system uses free satellite data and open-source software, which means other cities with stressed river corridors could use the same approach without spending a lot of money,” said Adhikari.
Environmentalist and head of the environmental science department of Babasaheb Bhimrao Ambedkar University Prof Venkatesh Dutta said the sediments of Gomti are full of heavy metals. “The river should have a natural river bank and indigenous species instead of engineered landscape and walled rivers. The rivers are by themselves best pollinators. The river must have natural landscape, floodplain and river terrace but the reality is we are losing the Gomti,” he said.
