Open AccessSpatial patterns in oxygen and redox sensitive biogeochemistry in tropical forest soils
Author(s) -
Liptzin Daniel,
Silver Whendee L.
Publication year - 2015
Publication title -
ecosphere
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.255
H-Index - 57
ISSN - 2150-8925
DOI - 10.1890/es14-00309.1
Subject(s) - biogeochemical cycle , biogeochemistry , soil water , spatial ecology , environmental science , spatial variability , ecology , redox , tropical forest , soil science , wetland , soil ph , nutrient , hydrology (agriculture) , trace gas , environmental chemistry , atmospheric sciences , geology , chemistry , biology , mathematics , geotechnical engineering , organic chemistry , statistics
Humid tropical forest soils are characterized by warm temperatures, abundant rainfall, and high rates of biological activity that vary considerably in both space and time. These conditions, together with finely textured soils typical of humid tropical forests lead to periodic low redox conditions, even in well‐drained upland environments. The relationship between redox and biogeochemical processes has been studied for decades in saturated environments like wetlands and sediments, but much less is known about redox dynamics in upland soils. The goal of this study was to understand the spatial variability of redox sensitive biogeochemistry within and across two forest types at the ends of a high rainfall gradient (3500 to 5000 mm y −1 ) in the Luquillo Experimental Forest, Puerto Rico. The two sites differed significantly in average soil chemical and physical properties, but the scale of variability was similar across sites, with greater variability in soil gas concentrations than extractable Fe and P. Soil P and Fe pools and trace gas concentrations were more strongly correlated with each other and exhibited more spatial structure at the wetter site. While the within‐site relationships among these redox sensitive variables were typically weak, the relationships across sites were much stronger. We provide a conceptual model that elucidates how the strength of the relationships between indicators of redox‐sensitive biogeochemical processes depends on the spatial scale of analysis.