Kadalundi’s shrinking mudflat ecosystem keeps birds away

Kadalundi’s shrinking mudflat ecosystem keeps birds away

Subject: Environment

Section: Ecosystem

Context:

• Kadalundi, a village on the southwest coast in Kozhikode district of Kerala, had about 8 hectares of nutrient­ rich inter­tidal mudflats in the early 2000s. Today, the expanse of mudflats in the estuary of the Kadalundipuzha river has reduced to about 1 hectare. This too is gradually being covered with sand, depriving prey to thousands of shorebirds that migrate from colder climes in winter to the village.

About Mudflat Ecosystem:

• Mudflats refer to land near a water body that is regularly flooded by tides and is usually barren (without any vegetation).
• It is also known as tidal flats and formed upon the deposition of mud by tides or rivers.
• Mudflats and mangroves together constitute an important ecosystem.
• Mudflats serve to protect coastal lands from the eroding forces of nature and also provide an important habitat for shore birds.

Reasons of Shrinking

• The main reason behind the drop in water levels is sedimentation, the process of particles such as sand and stones settling to the bottom of a body of water.
• Human activities, such as unsustainable consumption of water.
• Increasing temperature and potential evapotranspiration (PET) due to climate change are also main reasons for shrinking.

What are the effects of the climate changes on water bodies?

• World’s largest lakes and reservoirs – Have shrunk more than 50% over the 3 decades.
• From these water bodies, approximately 600 cubic km of water was lost between 1992 and 2020 which is equivalent to the total water used in the United States for the entire year of 2015.
• Sedimentation – Main cause of the decline in the water storage for more than more than half of the reservoirs located in peninsular India.
• Sedimentation has a larger impact than hydro climate variability such as droughts and recovery from droughts.
• Among the worst affected natural lakes in the country is Ladakh’s Tso Moriri.
• Water consumption – Unsustainable water consumption in the world’s large lake have led to the decreased water levels.
• Arctic lakes – Shrunk as a result of a combination of changes in precipitation, runoff, temperature, and PET, which are likely a concurrent result of natural variability and climate change.
• Humid tropics and high altitudes – Natural lakes located in humid tropics and high altitudes are also experiencing water shortages.
• Human activities – Such as unsustainable consumption of water and increasing temperature and potential evapotranspiration (PET) have led to reduced water levels.

Implications of shrinking waterbodies:

• Water scarcity: The decline of large lakes and reservoirs has severe implications for global water resources.
• The reduced availability of freshwater impacts various sectors, including agriculture, energy, and human consumption.
• It exacerbates water scarcity, leading to conflicts and socio-economic challenges.
• The sedimentation of sand on mudflats not only brings down the amount of migratory prey there, but also helps mangroves easily proliferate. The  viviparous mangroves according to researchers, can display an aggressive invasive behaviour.
• Food security: Agriculture heavily relies on water resources for irrigation.
• As lakes and reservoirs shrink, the water supply for agricultural activities diminishes, impacting crop yields, food production, and food security.
• This can lead to increased food prices and food shortages.
• Energy generation: Many hydropower plants depend on large lakes and reservoirs for water supply.
• The decline in water levels affects hydropower generation, leading to energy shortages and an increased reliance on other energy sources, potentially impacting energy prices.
• Ecosystem disruption: Large lakes and reservoirs support diverse ecosystems, and their decline threatens the survival of aquatic plants and animals.
• It disrupts the ecological balance, affecting biodiversity and the overall health of ecosystems.
• Socio-economic impacts: The decline of lakes and reservoirs directly affects human populations. Communities relying on these water bodies for drinking water, agriculture, and livelihoods face water shortages, increased competition, and potential migration.
• This poses significant socio-economic challenges, particularly in regions heavily dependent on these water sources.