Context

• Increasing urbanisation and changing climatic trends with a limited resource base has created an undue pressure on the natural resources making the cities vulnerable to climate changes. 
• Deforestation, conversion of agricultural lands, creating infrastructure beyond the carrying capacity, loss of wetlands, distortion of watershed are some of the activities taken up to support the rising population in cities.  
• It is predicted that about 60 percent of the world population will be living in urban areas by 2025 wherein India will nearly add about 416 million urban dwellers to cities by 2050.

Worrying Trend

• The Global Climate Risk Index 2021 ranks India as the 7th most-affected country from climate-related extreme weather events such as storms, floods, heatwaves, etc. Widespread drought in July 2019 followed by devastating floods in August 2019 in Chennai can be seen as a perfect example of extreme events due to changing climatic trends. Furthermore, flash floods of Uttarakhand (2013) and Wayand (2018), extreme and frequent cyclones of eastern coast are also the instances probing for proper understanding and planning for such unusual events.  
• As per the World Bank report ‘High and Dry: Climate Change, Water and the Economy’, water scarcity, aggravated by climate change, could cost some regions up to 6 percent of their GDP. 
• As per the assessment by NITI Aayog’s Composite Water Management Index, over 21 major Indian cities including Delhi, Bengaluru, Hyderabad, and Chennai, would run out of groundwater very soon, affecting nearly 100 million people. 
• Besides this, infringement and intrusion of urban water lakes and ponds has made cities more vulnerable to flooding and more susceptible to climate change.  

Nature-Based Solutions

• Nature-based solutions (NBS) are actions to protect, sustainably manage, or restore natural ecosystems that address societal challenges such as climate change, human health, food and water security, and disaster risk reduction effectively and adaptively, simultaneously providing human well-being and biodiversity benefits. 
• For example, a common problem is the flooding in coastal areas that occurs as a result of storm surges and coastal erosion. This challenge, traditionally tackled with manmade (grey) infrastructure such as sea walls or dikes, coastal flooding, can also be addressed by actions that take advantage of ecosystem services such as tree planting. 
• Planting mangroves in coastal areas reduces the impact of storms on human lives and economic assets, and provides a habitat for fish, birds and other plants supporting biodiversity.

Benefits

• Nature-based solutions enhance existing and man-made infrastructure offering economic, social, and environmental benefits. These solutions not only deliver short term benefits but also extend the long-term benefits to present and future stakeholders.  
• For instance, in China, restoration of the degraded Loess Plateau benefited over 2.5 million people with the introduction of sustainable farming practices. In greater Manchester, over £150 million/year were saved for healthcare costs with access to green spaces and tree planting activities. 
• Globally, it is also estimated that the mangrove forests can save about USD 80 billion per year by avoiding losses from coastal flooding and protecting up to 18 million people. 
• Nature-based solutions also generate economic gains through immediate job creation, increased business productivity and tourism.  
• Notably, nature-based solutions do not necessarily require additional financing sources but usually involve redirecting and making more effective use of existing financing sources. 

NBS for Water Conservation

• Nature-based solutions to manage the water sector involves enhancing and delivering natural ecosystem services such as mangroves protecting shorelines from storms, peatlands sequestering carbon, wetlands filtering contaminated water, lakes storing large water supplies, and floodplains absorbing excess water runoff.
• In urban set up, the idea is to integrate grey infrastructure such as dams, seawalls, roads, pipes or water treatment plants to support and complement natural infrastructure such as promoting green roofs, open and green  buildings, planting trees and terrace gardens, recycling and reusing water.
• It is also crucial to to recollect the oldest and most effective method of tapping rainwater at source. The urban households can plan and design houses to store rainwater for at least non-potable uses. 
• Tapping rainwater is also required to rejuvenate urban lakes and ponds. These local ponds and lakes act as a sponge and thermoregulators, helping areas to accumulate rainwater, enhance groundwater and regulate micro-climate. The revival of local water bodies can also support cities to be less dependent on far away water sources for meeting water demands. 
• Creation and maintenance of urban green spaces such as parks, community gardens, playgrounds, etc. is also recommended. Significance of green landscapes should also not be undermined as the parks and recreational spaces can help in absorbing the free flow storm water avoiding cities to get water logged. 
• One of the practices to avoid storm water being practiced in China is ‘Sponge Cities’. The concept is to absorb excessive rainfall through soil infiltration while retaining it in underground tunnels and storage tanks, only discharging it into the river once water levels are low enough.

Conclusion

• With the rising global challenges of climate change, urbanisation, biodiversity loss, as well as the current global health and economic crisis, the investment in nature-based solutions should be well promoted. 
• Launching of ‘LiFE Movement’ by Prime Minister Narendra Modi, in 2022, can be recorded as one of the initiatives to set the path for nature-based solutions to modern day concerns. The movement is to promote an environmentally conscious lifestyle that focuses on ‘mindful and deliberate utilisation’ instead of ‘mindless and destructive consumption’. 
• LiFE envisions making individual behaviour change the centre of the climate action narrative in the world and making sustainable lifestyles a global mass movement. This kind of movement will encourage the common people to contribute to the battle against climate change.

https://www.iucn.org/our-work/nature-based-solutions