Plant functional group diversity promotes soil protist diversity

Area of Science:

• Ecology
• Soil Science
• Protistology

Background:

• Plant diversity is a key driver of ecosystem functioning.
• The impact of plant diversity on soil communities, especially those not directly linked to plants like heterotrophic protists, is not fully understood.
• Testate amoebae are important soil-dwelling protists that play roles in nutrient cycling.

Purpose of the Study:

• To investigate how plant functional group diversity influences the diversity and community structure of testate amoebae in synthesized grassland ecosystems.
• To determine if the effects of plant diversity cascade down to heterotrophic protists in the food web.

Main Methods:

• Synthesized grassland ecosystems with varying numbers of plant functional groups (FGN), keeping the plant species number constant.
• Assessed changes in testate amoebae communities, including species number, density, and composition.
• Analyzed the relationship between FGN and testate amoebae community metrics.

Main Results:

• Increasing FGN from 1 to 3 linearly enhanced testate amoebae species number and saturatingly increased total community density.
• A shift in testate amoebae species composition occurred between FGN 2 and 3, with approximately one-quarter of resident species being replaced.
• Overall species density increased with FGN, but community evenness remained unaffected, although one common species, Trinema lineare, became more abundant.

Conclusions:

• Plant functional group diversity significantly affects the diversity and density of soil-dwelling testate amoebae.
• The study demonstrates that plant diversity effects can propagate through food webs to influence protist communities.
• Findings provide new insights into the biogeographical distribution patterns of protists in relation to terrestrial plant diversity.