Climate change impacts on selected global rangeland ecosystem services

Area of Science:

• Ecology
• Climate Science
• Environmental Modeling

Background:

• Rangelands are Earth's dominant land cover, providing vital ecosystem services.
• Projected increases in reliance on rangelands necessitate understanding their climate sensitivity.
• Accurate global rangeland assessments are critical for predicting future ecosystem service provision.

Purpose of the Study:

• To quantify global changes in rangelands under future climate scenarios using a novel ecosystem model.
• To assess the sensitivity of net primary production (NPP), soil organic carbon, and livestock viability to climate change.
• To identify regions most vulnerable to climate-induced rangeland degradation and inform adaptation strategies.

Main Methods:

• Development and application of a new, moderately complex ecosystem model for global rangeland analysis.
• Simulation of rangeland responses under Representative Concentration Pathway (RCP) 8.5 for the year 2050.
• Quantification of changes in net primary production (NPP), soil organic carbon, and livestock carrying capacity.

Main Results:

• Global mean annual NPP may decline by 10 g C m⁻² year⁻¹, with herbaceous NPP slightly increasing.
• Significant regional variations observed: productivity increases in North America (21%), but declines in Western Africa (-46%) and Australia (-17%).
• Soil organic carbon projected to increase in Australia, the Middle East, and Central Asia, but decline in African savannas (-18%).
• Livestock populations projected to decline 7.5–9.6%, resulting in economic losses of $9.7–$12.6 billion.

Conclusions:

• African forage production is highly sensitive to climate change, impacting over 180 million pastoralists.
• The developed model provides a valuable tool for forecasting rangeland conditions and identifying areas of concern.
• Quantifying adaptation costs and benefits is essential for developing effective rangeland management policies.