Open AccessAboveground competition influences density‐dependent effects of cordgrass on sediment biogeochemistry
Author(s) -
Walker Janet B.,
Rinehart Shelby,
GreenbergPines Gabriel,
White Wendi K.,
DeSantiago Ric,
Lipson David A.,
Long Jeremy D.
Publication year - 2022
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.8722
Subject(s) - biogeochemistry , salt marsh , ecology , competition (biology) , environmental science , biology , plant ecology , spartina , sediment , plant community , perennial plant , oceanography , marsh , wetland , geology , paleontology , ecological succession
Interspecific interactions between plants influence plant phenotype, distribution, abundance, and community structure. Each of these can, in turn, impact sediment biogeochemistry. Although the population and community level impacts of these interactions have been extensively studied, less is known about their effect on sediment biogeochemistry. This is surprising given that many plants are categorized as foundation species that exert strong control on community structure. In southern California salt marshes, we used clipping experiments to manipulate aboveground neighbor presence to study interactions between two dominant plants, Pacific cordgrass ( Spartina foliosa ) and perennial pickleweed ( Sarcocornia pacifica ). We also measured how changes in cordgrass stem density influenced sediment biogeochemistry. Pickleweed suppressed cordgrass stem density but had no effect on aboveground biomass. For every cordgrass stem lost per square meter, porewater ammonium increased 0.3–1.0 µM. Thus, aboveground competition with pickleweed weakened the effects of cordgrass on sediment biogeochemistry. Predictions about plant–soil feedbacks, especially under future climate scenarios, will be improved when plant–plant interactions are considered, particularly those containing dominant and foundation species.