PANAJI
Two of Goa’s major rivers -- Zuari and Sal -- face significant anthropogenic pressures, including pollution from urbanization and untreated sewage leading to water quality degradation and severe impact on vegetation or plant composition and overall ecological damage, reveals a fresh study.
A joint study undertaken by the students of the Goa University and Kyambogo University, Kaliro-Uganda reveals that both the rivers are under significant anthropogenic pressure, potentially leading to further increases in their pollution levels.
The study “Impact of Anthropogenic Pollution on the Plant Species Diversity and Composition Along the Riparian Ecotones of Goa's Sal and Zuari Rivers’ was undertaken by Moses Musisi from the Department of Science, National Teachers' College, Kaliro, Kyambogo University, Kaliro, Uganda, Celly Quadros of Botany Discipline, School of Biological Sciences and Biotechnology, Goa University and Krishnan Sellappan from the department of Botany, Government College of Arts and Sciences, Quepem.
Anthropogenic pressures are increasingly constraining the health of riparian ecosystems by exposing their remnant vegetation to edge effects.
“Despite being at the land–water interface, conservation efforts have often overlooked how water pollution may indirectly exacerbate the broader impacts of anthropogenic pressures on riparian vegetation along riparian ecotones,” the researchers said adding that the study examined the impacts of anthropogenic pollution on plant species diversity and composition in riparian ecosystems.
According to the researchers, the main human activities along the rivers were sewage disposal, construction, urbanization, and fish farming. Anthropogenic pollution has a significant effect on plant composition; as such, the nature of human activity will determine the plant composition of that area
“The study identified significant effects of anthropogenic pollution on plant composition along the rivers. Sewage disposal and urbanization emerged as the most impactful activities, while fishing had the least influence. This gradient of impact has shown that high nutrient inputs from sewage and urban runoff significantly alter aquatic and riparian vegetation by favoring nutrient-tolerant species,” the study stated.
The study observed that urbanized areas, particularly along the River Sal, exhibited reduced vegetation cover. This may be likely due to high levels of runoff pollution and edge effects. The compounded effects of water flow alterations and soil texture changes further accelerate declines in riparian plant diversity.
“The riparian plant species diversity along the Sal and Zuari rivers is moderate. This implies that the riparian vegetation has suffered significant human disturbances that have reduced its abundance along the rivers' ecotones. As the seasons changed from monsoon to pre-monsoon, the riparian plants became less diverse, rich, and even,” it added.
Anthropogenic disturbances (hemeroby) and water pollution negatively impact plant diversity in riparian ecosystems. In addition, water pollution plays a pivotal role in mediating the effects of human disturbances on plant diversity, thus serving as a significant pathway through which human disturbances impact plant species diversity.
