Linking nematodes and ecosystem function: a trait-based framework.

Emerging knowledge of plant–soil biotic interactions and the role of soil organisms in shaping the world aboveground is advancing our understanding of ecosystem function. Nematodes are the most abundant animals on Earth. They are morphologically and functionally diverse, and play key roles in ecosystem function, making them ideal for developing a trait-based understanding of adaptation to the environment and for assessing their contributions to ecosystem function. Trait-based approaches allow us to capture the functional attributes of organisms beyond their taxonomic identity, provide insights on evolutionary fitness, and make global comparisons possible. We propose the nematode economics spectrum (NES), analogous to the plant economic spectrum, which describes the tradeoffs among growth, reproduction, and survival, potentially enabling us to predict the impacts of global change on nematode ecological strategies and the associated changes in ecosystem function. Trait-based approaches are being increasingly adopted to understand species' ecological strategies and how organisms influence ecosystem function. Trait-based research on soil organisms, however, remains poorly developed compared with that for plants. The abundant and diverse soil nematodes are prime candidates to advance trait-based approaches belowground, but a unified trait framework to describe nematode ecological strategies and assess their linkages with ecosystem function is lacking. We categorized nematode traits as morphological, physiological, life history, and community clusters, and proposed the nematode economics spectrum (NES) to better understand nematode ecological strategies and their association with ecosystem function. We argue that bridging the NES and the plant economics spectrum will facilitate a more holistic understanding of ecosystem carbon and nutrient cycling under global change. [ABSTRACT FROM AUTHOR]