Introduction

• Woody encroachment is altering open ecosystems like savannahs and grasslands, negatively impacting native species.
• A study from Global Change Biology highlights a decline in grassland bird populations due to increased tree cover.

Characteristics and Importance of Open Ecosystems

• Grasslands and savannahs cover 40% of Earth’s landmass, hosting diverse flora and fauna.
• They are vital for species like elephants and grassland birds but are rapidly diminishing.

Factors Driving Woody Encroachment

• Human activities such as agriculture, development, and overgrazing threaten these habitats.
• Woody encroachment involves the conversion of open areas to dense tree and shrub habitats, reducing biodiversity.

Effects of Climate Change

• Increased atmospheric CO2 promotes tree growth over grasses, altering ecosystem dynamics.
• Trees suppress grasses through shading and fire suppression, impacting species dependent on open habitats.

Regional Impact

• In India, grasslands face significant encroachment, especially within protected areas.
• Recent studies reveal a 34% reduction in grassland cover and an 8.7% increase in tree cover in national parks over the past three decades.

Historical and Current Challenges

• Colonial policies favored timber production over open ecosystems, leading to habitat conversion and suppression of traditional management practices.
• Modern views on carbon sequestration also contribute to the neglect of grassland conservation.

Biodiversity Loss

• Woody encroachment has led to a decline in grassland birds and other species.
• Examples include a significant drop in bird populations in southern Africa and impacts on rodent species in India’s Banni grasslands.

Invasive Species and Plantation Programs

• Large-scale tree plantations, such as Prosopis juliflora, have transformed grasslands into woody areas.
• Introduced species like eucalyptus and Malabar silk-cotton trees further disrupt native ecosystems.

Recommendations for Action

• Increased research and long-term monitoring are essential to understand and mitigate the impacts of woody encroachment.
• Policy changes should address colonial-era misconceptions and prioritize the protection of open ecosystems.