GCTE’s Focus 4 links two major areas of research that have worked largely independently up until now: global change and biodiversity. Changes in land use, atmospheric composition and climate directly affect biodiversity and ecological complexity, and consequently ecosystem functioning. The goals of Focus 4 are to determine the relationship between ecological complexity and ecosystem functioning; to evaluate how global change affects biodiversity and ecological complexity; and to elucidate the consequences of these effects for policy and resource management.

Activity 4.1: Effects of biodiversity on ecosystem functioning and its ability to respond to global change. [Leader: Michel Loreau]

Objective: To determine the relationship between biodiversity and ecosystem functioning and the amounts and types of complexity that can be changed before significant changes in ecosystem functioning occur.

• Task 4.1.1: Experimental assessment of the effects of changes in biodiversity on ecosystem functioning using synthetic communities. [Shaid Naeem]
• Task 4.1.2: Effects of biological invasions on changes in biodiversity and ecosystem functioning. [Mark Lonsdale and Monserrat Vila]
• Task 4.1.3: Theory and models of the effects of changes of biodiversity on ecosystem functioning [Michel Loreau and Peter de Ruiter]
• Task 4.1.4: Removal experiments on the role of biodiversity on ecosystem functioning [Sandra Diaz and Terry Chapin]

Activity 4.2: Effects of global change on biodiversity and ecosystem functioning. [Leader: Volkmar Wolters]

Objective: To determine the impacts of changes in the global climate and land use on biodiversity and ecosystem functioning.

• Task 4.2.1: Effects of changes in climate and atmospheric composition on biodiversity [Peter Reich]
• Task 4.2.2: Effects of land-use change on biodiversity [Valerie Brown and Volkmar Wolters]
• Task 4.2.3: Theory and models of the effects of global climatic change on ecosystem functioning [Steve Pacala]
• Task 4.2.4: Scenarios of change in biodiversity [Osvaldo Sala]

Activity 4.3: Landscape complexity and functional processes. [Leader: Sandra Lavorel]

Objective: To determine how important landscape processes such as disturbance and migration are affected by global change

• Task 4.3.1: Effects of landscape complexity on functional processes [Debra Peters]
• Task 4.3.2: Responses of vegetation to changes in land use and in disturbance regimes [Sue MacIntyre and Sandra Diaz]
• Task 4.3.3: Fragmentation, dispersal and migration [Steve Higgins]
• Task 4.3.4: Effects of landscape complexity on the persistence of plant and animal populations faced with global change Rodolfo Dirzo [Rodolfo Dirzo]