Context-dependent controls of periphyton across the littoral-benthic habitat of deep, clear lakes

Littoral-benthic habitats can play a key role in governing whole ecosystem production within lakes. Typical controls of littoral-benthic production can include light, nutrients, and grazers, although, studies examining production across the photic zone in deep lakes are limited. This study investigates the role of nutrient limitation and inhibition from the shallow to deep (lower limit of the photic zone) littoral-benthic habitat of lakes with varying trophic states. To achieve this aim we use a combination of nutrient diffusing substrates (NDS), water column nutrient data, and photosynthetically active radiation (PAR) measurements. We observed that periphyton nutrient limitation and inhibition vary with depth and habitat. Differences were primarily driven by the concentration of dissolved inorganic nitrogen (DIN) and the availability of PAR. Less DIN and more PAR favored N limitation and P inhibition, whereas more DIN and less PAR favored P limitation and N inhibition. Furthermore, we found differences in nutrient limitation in the shallow littoral-benthic habitat of lakes may be affected by biological factors (density of high-level predators) than by surrounding substrate types, although these differences may have arisen from other, non-biological factors (e.g., nutrient supply from groundwater or surface runoff). Our findings reveal that periphyton nutrient responses across the littoral-benthic zone for clear lakes are context-dependent, influenced by a complex interplay of light and nutrient availability. The shifting roles of nitrogen and phosphorus across depth gradients call for a more nuanced understanding of periphyton responses in lakes with extensive photic zones. Considering the importance of littoral-benthic habitat for whole lake function, additional studies exploring the role of nutrient, light, and consumers should occur across depth for clear, deep-water lakes.

Level thesis:degree_level

Master's Degree

Year dc:date.issued

2024

Author dc:creator

• San Pedro, Aldo Preston

Advisor dc:contributor.advisor

• Chandra, Sudeep

Committee members dc:contributor.committeemember

• Parchman, Thomas L
• Blaszczak, Joanna R

• inhibition
• limitation
• nitrogen
• nutrient diffusing substrate (NDS)
• periphyton
• phosphorus

Language dc:language.iso

en_US, English

Repository record dc:identifier.uri

https://scholarwolf.unr.edu/handle/11714/11240

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/11240