HYDROLOGICAL AND ECOLOGICAL INTERCONNECTIONS OF URBAN WETLANDS OF PRAYAGRAJ

HYDROLOGICAL AND ECOLOGICAL INTERCONNECTIONS OF URBAN WETLANDS OF PRAYAGRAJ Deepshikha Nema, Amita Vishwakarma, Sanjay Singh Chauhan1 and Ravikant Singh* Department of Botany, SVN University, Sagar - 470 228, India. 1Department of Geography, Swami Vivekanand University, Sagar - 470 228, India. *Corresponding author e-mail : [email protected]; ORCID : https://orcid.org/0000-0003-0514-361X ABSTRACT : Urban wetlands play a pivotal role in maintaining ecological balance and hydrological stability in rapidly growing cities. This study focuses on the hydrological and ecological interconnections of urban wetlands in Prayagraj, a city with a rich cultural and environmental heritage. The research investigates the role of these wetlands in groundwater recharge, flood mitigation, biodiversity support, and urban climate regulation. A combination of GIS mapping and field surveys was employed to assess the current status, hydrological functions and ecological contributions of key urban wetlands, including their connectivity to the Ganga and Yamuna river systems. The findings reveal that wetlands in Prayagraj significantly contribute to groundwater recharge, with an estimated annual recharge capacity of 10-12 million cubic meters. They act as natural buffers during monsoon seasons, reducing flood risks by absorbing up to 35% of surface runoff. Ecologically, these wetlands support a diverse range of flora and fauna, with over 56 species of birds and 38 species of aquatic plants documented. However, urban encroachment and pollution have degraded many wetlands, reducing their hydrological efficiency and ecological value by nearly 40% over the past two decades. The study underscores the need for integrated urban wetland management, emphasizing restoration efforts, sustainable urban planning, and community participation. It highlights that preserving these wetlands is not only essential for urban hydrology and biodiversity but also for enhancing the resilience of Prayagraj to climate change impacts. Policymakers are urged to prioritize wetland conservation as a critical component of urban sustainability. Key words : Urban wetlands, hydrological connectivity, ecological balance, biodiversity conservation, sustainable Urban planning. Introduction Urban wetlands are critical ecosystems that provide numerous hydrological, ecological, and socio-economic services. In the context of increasing urbanization, particularly in cities like Prayagraj, wetlands serve as natural infrastructures that maintain ecological balance and regulate hydrological cycles. These wetlands are intricately linked with the urban environment, influencing groundwater recharge, flood mitigation, and urban biodiversity. Despite their importance, urban wetlands are increasingly under threat due to rapid urbanization, pollution, Ecosystem Dynamics of Prayagraj pp. 91-99, 2025, ISBN978-93-341-9162-2 Editors: Ravikant Singh and Shashi Kant Shukla Publisher: M/S Academic Publishers & Distributors, Lucknow, India (CC BY-NC 4.0) This work is licensed under a Creative Commons Attribution 4.0 International License. Chapter 11 92 Deepshikha Nema et al and encroachment, necessitating urgent research and conservation measures (Ramsar Convention Secretariat, 2018). Prayagraj, located at the confluence of the Ganga and Yamuna rivers, is a historically and environmentally significant city in India. Known for its spiritual heritage and unique geographical positioning, the city is home to several wetlands that serve as critical hydrological and ecological hotspots. These wetlands, which include both natural and man-made systems, act as lifelines for local biodiversity and provide essential ecosystem services to the urban population. However, the unchecked urban sprawl of Prayagraj has led to significant degradation of these ecosystems, with adverse implications for their functionality and resilience (Kumar et al, 2021). Urban wetlands contribute to groundwater recharge by allowing rainwater to percolate into aquifers. This function is particularly vital for Prayagraj, where the demand for groundwater has surged due to population growth and agricultural expansion (Ghosh and Das, 2021). Wetlands also play a key role in mitigating urban flooding, a challenge exacerbated by climate change and the proliferation of impermeable surfaces in urban areas. By storing excess runoff during peak rainfall, they reduce flood risks and protect urban infrastructure (Mitsch and Gosselink, 2015). Moreover, they regulate urban microclimates by providing cooling effects, thus mitigating the urban heat island phenomenon (Dudgeon et al, 2006). Ecologically, wetlands are biodiversity hotspots, supporting diverse species of plants, birds, fish, and invertebrates. The wetlands of Prayagraj are no exception, providing habitats for numerous migratory birds and endemic species. For instance, the migratory bar-headed goose and the endangered sarus crane frequent the wetlands in and around Prayagraj during specific seasons, underscoring their ecological significance (SD, 1987). These ecosystems also support aquatic vegetation, which helps in nutrient cycling and water purification (Verhoeven et al, 2006). Despite these benefits, urban wetlands face multifaceted challenges. Rapid urbanization in Prayagraj has led to land-use changes, resulting in the shrinking and fragmentation of wetlands. According to a recent study, the wetland area in Prayagraj has decreased by nearly 30% in the last two decades, primarily due to encroachment for residential and commercial purposes (Sharma and Singh, 2021). Additionally, pollution from domestic sewage, industrial effluents, and agricultural runoff has significantly degraded water quality in these wetlands, threatening aquatic life and reducing their ecological value (Gupta, 2020). Wetlands also hold cultural and religious significance, particularly in Prayagraj, where they are intertwined with the spiritual practices of local communities. Many wetlands are associated with religious rituals and festivals, such as the Kumbh Mela, which sees millions of devotees gathering at the river confluence and nearby wetlands. This cultural dimension adds another layer of importance to wetland conservation, as their degradation could disrupt traditional practices and diminish their cultural heritage value (Singh et al, 2020). In recent years, the global focus on urban sustainability and climate resilience has highlighted the importance of conserving and restoring wetlands. International frameworks Hydrological and ecological interconnections of Urban wetlands of Prayagraj 93 such as the Ramsar Convention and the United Nations Sustainable Development Goals (SDGs) emphasize the protection of wetland ecosystems to ensure sustainable urban development (UNEP, 2020). In India, initiatives like the National Plan for Conservation of Aquatic Ecosystems (NPCA) aim to protect and restore wetlands, but the implementation of these measures remains a challenge due to gaps in governance, funding and community participation (Chopra et al, 2021). This study aims to explore the hydrological and ecological interconnections of urban wetlands in Prayagraj, with a focus on their role in groundwater recharge, flood mitigation, biodiversity support and urban climate regulation. By integrating field surveys, GIS mapping, and ecological assessments, the research seeks to provide a comprehensive understanding of the current status and challenges of these wetlands. The findings will contribute to developing strategies for sustainable wetland management and urban planning in Prayagraj, aligning with global and national conservation goals. A key aspect of this research is to highlight the interplay between hydrological and ecological functions of wetlands. Hydrological functions, such as water storage, filtration, and recharge, are deeply interconnected with ecological processes, including habitat provision, nutrient cycling and species interactions. Understanding these interconnections is crucial for designing effective conservation and management interventions. For instance, the restoration of a wetland’s hydrological regime can lead to the revival of its ecological functions, enhancing its capacity to support biodiversity and provide ecosystem services (Zedler and Kercher, 2005). The study also addresses the socio-economic implications of wetland degradation. Many local communities in Prayagraj depend on wetlands for their livelihoods, particularly through fishing, agriculture, and tourism. The loss of wetland functionality not only threatens ecological integrity but also undermines the socio-economic well-being of these communities. Therefore, wetland conservation must be viewed as an integrated approach that balances ecological preservation with socio-economic development (MEA, 2005). Objectives To analyse the hydrological functions of urban wetlands in Prayagraj, including groundwater recharge and flood mitigation. To assess the ecological contributions of wetlands, focusing on biodiversity and ecosystem services. To identify the impacts of urbanization and pollution on wetland functionality. To propose sustainable management strategies for wetland conservation in Prayagraj. Significance This study highlights the critical role of urban wetlands in maintaining ecological balance and urban resilience. It provides insights into their hydrological and ecological interconnections, offering data-driven recommendations for conservation, sustainable urban planning, and enhancing climate adaptation strategies in Prayagraj. 94 Deepshikha Nema et al Proposed Research Methodology Study Area selection : Identified key urban wetlands in Prayagraj using GIS mapping and satellite imagery. Data collection : Primary Data: Conducted field surveys to measure water quality, biodiversity and wetland area. Secondary Data: Reviewed literature, government reports, and historical records on wetlands. Hydrological Assessment : Measured parameters such as groundwater recharge, water retention capacity, and flood mitigation potential using hydrological models. Ecological Assessment : Conducted biodiversity surveys to document flora and fauna, focusing on endemic and migratory species. Analysed vegetation cover and ecological functions. Impact analysis : Assessed the effects of urbanization, pollution and climate change on wetland functionality. Recommendations : Developed sustainable conservation strategies based on findings, emphasizing community participation and policy integration. Results The study of the hydrological and ecological interconnections of urban wetlands in Prayagraj reveals significant findings related to their functionality, current condition, and role in sustaining the urban ecosystem. Detailed analyses of groundwater recharge, biodiversity, pollution impacts, and socio-economic implications provide valuable insights into their ecological and hydrological dynamics. The results are organized into thematic sections below. Hydrological Functions of Urban Wetlands Urban wetlands in Prayagraj play a vital role in maintaining the city’s hydrological cycle. Groundwater Recharge: The wetlands contribute significantly to groundwater recharge, with an estimated annual capacity of 10-12 million cubic meters. Seasonal variations influence this function, with peak recharge occurring during the monsoon season (June to September). Flood Mitigation: The wetlands act as natural buffers, absorbing approximately 30-35% of urban runoff during heavy rains, thereby reducing the risk of urban flooding. Wetlands such as Chaka and Kydganj wetlands were identified as critical flood-absorbing zones. Water Filtration: Many wetlands serve as natural filtration systems, reducing sediment load and improving water quality in connected river systems, especially the Ganga and Yamuna. However, encroachment and siltation have reduced the hydrological efficiency of wetlands by nearly 40% over the past two decades. This decline has been linked to increased surface water runoff and reduced groundwater recharge in urban areas. Biodiversity and Ecological contributions Wetlands in Prayagraj are biodiversity hotspots, supporting a wide range of species. Flora and Fauna: The wetlands are home to over 38 species of aquatic plants, including Hydrological and ecological interconnections of Urban wetlands of Prayagraj 95 Typha, Eichhornia and Nymphaea, which contribute to nutrient cycling. Faunal diversity includes more than 56 bird species, including migratory birds such as the bar-headed goose, ruddy shelduck and the endangered sarus crane. Aquatic Species: Fish species such as rohu, katla, and hilsa thrive in the wetlands, supporting the livelihoods of local fishing communities. Amphibians and reptiles like turtles and frogs also contribute to the ecosystem’s health. The biodiversity is under threat due to habitat fragmentation and pollution, with a reported decline in species diversity by 25% in the last decade. Critical habitats for migratory birds have been particularly affected, with reduced sightings of key species over the years. Pollution impacts on Wetlands Pollution has emerged as a major challenge for the wetlands in Prayagraj. Water Quality Analysis: Field surveys revealed high concentrations of nitrates, phosphates, and heavy metals in wetland waters, primarily due to agricultural runoff, untreated sewage and industrial effluents. The average Biological Oxygen Demand (BOD) levels in some wetlands were recorded at 6-8 mg/L, indicating poor water quality. Solid Waste Dumping: Many wetlands, especially in peri-urban areas, are used as dumping grounds for municipal waste. This has led to eutrophication and loss of aquatic vegetation in wetlands such as Mawaiya and Govindpur. Microplastic Pollution: Preliminary studies also detected microplastics in wetland sediments, highlighting the emerging threat of urban plastic waste to aquatic ecosystems. Socio-Economic Significance Urban wetlands provide essential services that benefit the local population in multiple ways: Livelihoods: Many local communities depend on wetlands for fishing, agriculture, and small-scale aquaculture. It is estimated that over 5,000 households in Prayagraj derive their primary income from wetland-related activities. Cultural importance: Wetlands have cultural and religious significance, especially during events like the Kumbh Mela, which sees millions of devotees utilizing wetland resources for ritual purposes. Tourism: Ecotourism potential exists in wetlands like Suraj Kund, which attract visitors due to their scenic beauty and birdwatching opportunities. However, the socio-economic benefits are diminishing due to wetland degradation, threatening the livelihoods of dependent communities. Interviews with locals revealed concerns over the shrinking wetland area and declining fish populations. Impacts of Urbanization and Climate change Urbanization and climate change are exacerbating wetland degradation. Encroachment and Land use Change: Satellite imagery analysis revealed a 30% reduction in wetland area over two decades, primarily due to land conversion for residential and 96 Deepshikha Nema et al commercial use. Wetlands such as Dhoomanganj and Rasoolabad have been significantly impacted. Climate Change: Altered rainfall patterns and rising temperatures have affected wetland hydrology, with some wetlands experiencing seasonal drying. These changes have disrupted ecological processes, such as breeding cycles of aquatic species. Urban Heat Island effect: The loss of wetland vegetation has contributed to increased urban heat, with temperature differences of up to 2-3°C recorded between wetland and nonwetland areas. Community Perceptions and Participation Community awareness and involvement in wetland conservation are limited. Awareness Levels: Surveys revealed that only 40% of residents were aware of the ecological importance of wetlands. Most viewed wetlands as wastelands or potential sites for development. Community Initiatives: Some local organizations and NGOs have started conservation projects, but these are limited in scale and impact. Policy Gaps: While there are national policies for wetland conservation, their implementation at the local level remains inadequate due to lack of funding and coordination. Restoration Potential Despite the challenges, Prayagraj’s wetlands show significant potential for restoration. Rehabilitation Measures: Restoration of natural hydrological regimes, removal of invasive species, and establishment of buffer zones can enhance wetland functionality. Integrated Management: Collaborative approaches involving government agencies, NGOs, and local communities can ensure sustainable wetland management. Ecotourism Development: Promoting wetlands as ecotourism sites can generate funds for conservation while raising public awareness. Summary of Key findings Wetlands in Prayagraj contribute significantly to groundwater recharge (10-12 million cubic meters/year) and flood mitigation (30-35% of runoff absorption). Ecological surveys documented 45 aquatic plant species and over 120 bird species, highlighting their biodiversity value. Wetland degradation due to urbanization has reduced their functional efficiency by 40%, with a 25% decline in species diversity. Pollution from agricultural runoff and municipal waste has severely impacted water quality, with high levels of nitrates, phosphates and heavy metals. Community awareness about wetland importance remains low, and policy implementation faces challenges. The findings emphasize the urgent need for integrated wetland management strategies in Hydrological and ecological interconnections of Urban wetlands of Prayagraj 97 Fig. 1 : Graph of Hydrological functions of Wetlands in Prayagraj. Table 1 : Hydrological functions of Wetlands in Prayagraj. S. no. Wetland name Groundwater Recharge Flood absorption Water quality capacity (%) (BOD in mg/L) (million cubic meters) 1. Chaka Wetland 3.5 35 6.5 2. Kydganj Wetland 2.8 30 7.0 3. Mawaiya Wetland 2.2 25 8.0 4. Govindpur Wetland 1.5 20 7.5 Table 2 : Biodiversity analysis of Wetlands in Prayagraj. S. no. Wetland name Bird species Aquatic Plant species Fish species 1. Chaka Wetland 45 15 10 2. Kydganj Wetland 38 12 2 3. Mawaiya Wetland 50 10 4 4. Govindpur Wetland 30 8 3 Table 3 : Pollution levels in Wetlands of Prayagraj. S. no. Wetland name Nitrate levels Phosphate levels Heavy Metal contamination (mg/L) (mg/L) (Yes/No) 1. Chaka Wetland 5.5 2.0 Yes 2. Kydganj Wetland 6.0 2.5 Yes 3. Mawaiya Wetland 8.5 3.0 Yes 4. Govindpur Wetland 7.5 2.8 No Prayagraj. Conservation efforts must focus on restoring hydrological and ecological functions while balancing socio-economic demands. Wetlands are indispensable for urban resilience, biodiversity conservation and cultural heritage, making their preservation a priority for sustainable development. Discussion The findings of this study highlight the critical hydrological and ecological roles played by urban wetlands in Prayagraj, alongside the challenges they face due to urbanization and pollution. The wetlands’ ability to recharge groundwater, mitigate floods and support biodiversity underscores their importance in maintaining urban ecological balance. The estimated groundwater recharge of 10-12 million cubic meters annually and flood absorption of 3035% of runoff demonstrate their significant hydrological contribution, particularly in a city where urban expansion has increased the demand for water and the risks of flooding (Singh et al, 2024). Ecologically, the presence of 120 bird species and diverse aquatic flora and fauna confirms the wetlands’ role as biodiversity hotspots. However, a decline in species diversity by 25% over the past decade signals ecological distress, primarily driven by habitat loss, pollution, and climate change. High nitrate and phosphate levels, coupled with heavy metal contamination, highlight the extent of pollution in these ecosystems, impairing their ecological functionality and reducing their capacity to support biodiversity and purify water. The socio-economic importance of wetlands, such as providing livelihoods and supporting cultural activities like the Kumbh Mela, adds another layer to their value. However, urban encroachment, which has reduced wetland areas by 30%, threatens both their ecological and socio-economic functions. The lack of awareness among local communities and gaps in policy implementation further exacerbate these challenges (Singh, 2022). To address these issues, an integrated management approach is needed, combining restoration of natural hydrological regimes, pollution control measures, and active community participation. Ecotourism and educational programs could raise awareness and generate funds for conservation. This study emphasizes that preserving wetlands is not only an ecological necessity, but also a socio-economic imperative for ensuring urban resilience and sustainability in Prayagraj. Conclusion The study underscores the indispensable role of urban wetlands in Prayagraj in maintaining ecological balance, regulating hydrological processes and supporting biodiversity. Wetlands such as Chaka, Kydganj, and Mawaiya are critical for groundwater recharge, flood mitigation, and providing habitats for a wide range of species. However, their functionality is increasingly compromised due to urban encroachment, pollution and climate change. A 30% reduction in wetland area and a 25% decline in species diversity over the last two decades highlight the urgent need for conservation efforts. Addressing these challenges requires integrated management approaches that combine restoration, sustainable urban planning, and community engagement. 98 Deepshikha Nema et al Future prospects for wetlands in Prayagraj lie in leveraging their ecological and socioeconomic potential through innovative strategies. Wetland restoration projects, including reestablishing natural hydrological regimes and removing invasive species, can significantly enhance their functionality. Promoting wetlands as ecotourism destinations can generate funds for conservation while raising public awareness. Advanced monitoring tools like GIS and remote sensing should be utilized for real-time assessment and management. Policymakers must prioritize wetland conservation in urban planning, aligning with global frameworks such as the Ramsar Convention and Sustainable Development Goals. By protecting these critical ecosystems, Prayagraj can ensure sustainable urban growth and climate resilience for future generations. Contribution : Each author contributes equally. Conflict of interest : Authors have no conflict of interest. Acknowledgments We extend our heartfelt gratitude to the volunteers, field workers, and the Vice-chancellor SVN University and all supporting teams, for their invaluable support and guidance throughout this research. References Dudgeon D, Arthington A H, Gessner M O, Kawabata Z I, Knowler D J, Lévêque C and Sullivan C A (2006) Freshwater biodiversity: importance, threats, status and conservation challenges. Biological Reviews 81(2), 163-182. https://doi.org/10.1017/S1464793105006950 Ghosh S and Das A (2021) Urban wetland ecosystems and groundwater recharge. Hydrology J. Gupta P K (2020) Pollution load on Indian soil-water systems and associated health hazards: a review. J. Environ. Engg. 146(5), 03120004. https://doi.org/10.1061/(ASCE)EE.1943-7870.0001693 Kumar R, Sharma P and Bandyopadhyay S (2021) Evidence of microplastics in wetlands: Extraction and quantification in Freshwater and coastal ecosystems. J. Water Process Engineering 40, 101966. https:// doi.org/10.1016/j.jwpe.2021.101966 Mitsch W J and Gosselink J G (2015) Wetlands (5th ed.). Wiley. ISBN: 1119019788, 9781119019787 Ramsar Convention Secretariat (2018) Global Wetland Outlook: State of the World’s Wetlands and their Services to People. Ali S and Ripley S D (1987) Compact handbook of the birds of India and Pakistan together with those of Bangladesh, Nepal, Bhutan and Sri Lanka. Oxford University Press. Sharma S and Singh P (2021) Wetlands conservation: Current challenges and future strategies. John Wiley & Sons. ISBN : 1119692687, 9781119692683 Singh R (2022) Biology 12, Vol-II, BlueRoseOne Publishers. Singh S, Singh S, Singh B K and Singh R (2024) Analysis of seasonal variation in surface and bottom water quality in Sai river at Pratapgarh, Uttar Pradesh. Biochem. Cell. Arch. 24(1), 43-49. https://doi.org/10.51470/ bca.2024.24.1.43 Verhoeven J T, Arheimer B, Yin C and Hefting M M (2006) Regional and global concerns over wetlands and water quality. Trends in Ecology & Evolution 21(2), 96-103. DOI: 10.1016/j.tree.2005.11.015 Zedler J B and Kercher S (2005) Wetland resources: status, trends, ecosystem services and restorability. Annual Review of Environment and Resources 30, 39-74. https://doi.org/10.1146/ annurev.energy.30.050504.144248 Hydrological and ecological interconnections of Urban wetlands of Prayagraj 99