Research out of York University investigates the role of species identity in facilitating the response to environmental changes in desert plants. Deserts ecosystems are threatened by shifts in precipitation patterns from climate change, pushing some species past certain thresholds.
Alessandro Filazzola, a recent York University PhD graduate and current post-doctoral Fellow at York and the University of Alberta, explores how plants respond to climate change along a large regional gradient spanning three desert provinces in this research published in the Journal of Vegetation Science.
A close up of Lacey phacelia (Phacelia tanacetifolia) growing under a shrub. This plant was one of three species that were seeded along the entire aridity gradient
Deserts are under threat of becoming drier and there is a need to understand the implications for our natural systems. The paper “Species‐specificity challenges the predictability of facilitation along a regional desert gradient” studies how species identity, soil nutrients and aridity drive positive interactions among plants along a regional gradient of semi-arid to hyper-arid.
“Desert ecosystems are already on the edge of life with extremes in rain and temperature, and we asked, ‘How do plants respond along a transition of increasingly drier desert areas?’” said Filazzola, who conducted this research under Faculty of Science Professor Christopher Lortie during his graduate studies.
The project found the positive interactions that exist between plants decrease with aridity, something that may occur in areas experiencing desertification.
A winter storm rolling in at Tejon Ranch. The middle site along the larger gradient of aridity, it is a transition zone between the San Joaquin and Mojave Deserts
The project, says Filazzola, was a massive undertaking that conducted seeding experiments for three years, across three desert provinces and over 600 kms and collaboration with land managers in the U.S. and an ecologist from France.
“We collaborated with global experts and local land managers to ensure this research has broad relevance. Almost 40 per cent of the world is drylands, home to more than a third of the human population, making research projects such as these incredibly important,” he said.
The research finds that biodiversity patterns of desert plants can change significantly along gradients of aridity, and that the positive effects of foundation species weakens at dry extremes.
These findings will have implications for desert ecosystems abroad.