Structure and functioning of dryland ecosystems in a changing world.

Area of Science:

• Ecology
• Environmental Science
• Sustainability Science

Background:

• Drylands cover a significant portion of the Earth's land surface and are crucial for global sustainability.
• These ecosystems are facing unprecedented environmental changes, including climate shifts, land cover alterations, and increased anthropogenic pressures.
• Understanding the complex interactions within drylands is essential for predicting their future and developing effective management strategies.

Purpose of the Study:

• To synthesize current knowledge on how various factors influence dryland ecosystem functioning at multiple spatial scales.
• To highlight the critical role of biotic attributes, such as species richness and functional traits, in maintaining ecosystem processes.
• To identify key drivers of change, including climate, grazing, nitrogen deposition, and land cover change, and their impacts on dryland resilience.

Main Methods:

• A comprehensive literature review and synthesis of existing research on dryland ecosystems.
• Analysis of how biotic attributes (species richness, abundance, traits) interact with abiotic factors (climate) and anthropogenic pressures (grazing, nitrogen deposition, land cover change).
• Examination of ecosystem functioning, focusing on primary productivity and responses to environmental change across various spatial scales.

Main Results:

• Biotic attributes, particularly species richness, are fundamental in maintaining essential ecosystem processes like primary productivity in drylands.
• Nitrogen deposition and grazing pressure are identified as significant global drivers impacting dryland ecosystem functioning.
• The traits of woody species are crucial in facilitating their expansion into former grassland areas, altering ecosystem structure.
• Species richness and abundance play a key role in modulating how ecosystem functioning responds to climate change.

Conclusions:

• Biotic attributes are pivotal for dryland ecosystem resilience and functioning, offering potential for active management.
• Effective conservation and restoration strategies for drylands must consider the interplay between biotic components and environmental changes.
• Managing biotic attributes at the local scale can enhance the capacity of drylands to withstand global environmental change and support sustainability.