Agricultural Expansion Threatens Biodiversity | 17 Dec 2024

Source: DTE

Why in News?

Recently, a study found that agricultural expansion is putting frog populations at risk in the Western Ghats. 

• It is part of the broader issue of agricultural expansion threatening biodiversity and causing habitat loss. 

What are the Key Findings of the Study? 

• Impact of Agricultural Expansion: Paddy fields and orchard expansion threaten frog population with paddy fields showing the lowest frog diversity and mango and cashew orchards housing the fewest frogs overall. 
• Decline of Rare Frog Species: Rare species, such as the CEPF Burrowing Frog (Minervarya cepfi) and the Goan Fejervarya (Minervarya gomantaki), were scarce in altered agricultural habitats. 
• Global and Local Amphibian Decline: About 40.7% (8,011 species) of amphibians worldwide are classified as threatened due to habitat destruction, pollution, climate change and diseases like chytridiomycosis. 
  • The Western Ghats, a biodiversity hotspot with 252 amphibian species (226 frogs), is facing habitat loss and declining frog populations. 
• Reasons for Decline: 
  • Loss of Microhabitats: Important microhabitats like rock pools, which protect frog eggs and tadpoles during dry spells, are being threatened by agricultural practices. 
  • Wetland Destruction: Agricultural and urban expansion is destroying wetlands crucial for frog reproduction. 
  • Agricultural Runoff: Agricultural runoff with pesticides and fertilizers harms water quality, endangering sensitive frog populations. 
  • Climate Change: Frogs' sensitivity to even minor environmental changes makes them vulnerable to climate change and human disturbances.

How Agricultural Expansion Threatens Biodiversity? 

• Deforestation: Conversion of forests into farmland is the leading cause of habitat decline.   
  • The area of primary forest worldwide has decreased by over 80 million hectares since 1990 resulting in habitat destruction, fragmentation, and eventual extinction. 
• Habitat Destruction: Between 1962 and 2017, approximately 340 million hectares of new cropland and 470 million hectares of natural ecosystems were converted into pastures globally leading to the destruction of critical ecosystems. 
• Monoculture: Large-scale agricultural practices like cattle ranching, soy, and palm oil cultivation replaces previously diverse ecosystems with monocultures and domesticated animals like cows, goats, sheep, and pigs. 
• Overuse of Chemicals: Industrial agricultural practices, especially the overuse of pesticides, fertilizers, and chemicals pollute groundwater and water systems, affecting both aquatic and terrestrial species.  
• Reduced Carbon Storage: Cropland stores significantly less carbon compared to the original forests or vegetation.  
  • Land-use changes could release 17 gigatons of CO2 in the long-term, worsening the climate crisis and threatening biodiversity by disrupting ecosystems. 
• Extinction Risks: Around 13,382 species of the 25,000 identified as threatened by the IUCN are endangered primarily due to agricultural land clearing and degradation.  
  • In addition, some 3,019 species are affected by hunting and fishing, and 3,020 by pollution from the food system. 
• Isolation of species: Agricultural expansion fragments habitats, isolating ecosystems and increasing species' extinction risk due to inbreeding, resource scarcity, and limited mobility. 

How Agricultural Expansion and Biodiversity Protection Can Be Balanced? 

• Closing yield Gaps: In many low-income countries, yields have stagnated despite growing food demand, leading to increased land clearing. 
  • Closing the yield gap in tropical countries with high biodiversity is crucial to meet food demands without encroaching further on natural ecosystems. 
  • Yield gap is the difference between current and potential yields. 
• Sustainable Intensification: Precision agriculture reduces pollution, emissions, and land use by optimizing fertilizer use, helping farmers maintain high yields with fewer environmental costs. 
• Diversified Farming Systems: Practices like intercropping (growing multiple crops together) or using cover crops can increase productivity without additional chemical inputs, enhancing soil fertility and pest control.  
• Land-Use Planning: Strong land-use planning and zoning policies that protect areas of high ecological value can direct agricultural growth while protecting sensitive ecosystems. 
• Healthier Diets: Diets that are more plant-based and less reliant on resource-intensive meat production require less cropland and have a lower environmental impact. E.g., seafood is a healthier alternative to red meats. 
• Reducing Food Waste: Reducing food loss and waste by half could reduce global food demand by 15%, and thus the need for 230 million hectares of additional cropland.

Conclusion 

• Agricultural expansion poses significant threats to biodiversity, exemplified by the decline in frog populations in the Western Ghats. However, sustainable practices like closing yield gaps, precision agriculture, diversified farming, and proper land-use planning can help balance food production with biodiversity protection, ensuring both environmental and food security.