Ecosystem nutrient uptake measurement (Amphibia)

Knowledge graph centered on Ecosystem nutrient uptake measurement (Amphibia) with 34 nodes and 118 connections. Top connected: aquatic insects, Ambystoma, Ambystoma tigrinum, Trichoptera, Ambystoma tigrinum nebulosm.

Method synopsis

Nutrient addition experiments in benthic substrates and sedge biofilms to measure ecosystem demand through exponential decay models. Measures uptake capacity of different pond compartments.

Synthesized from method descriptions across 2 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Animal-Driven Nutrient Supply Declines Relative to Ecosystem Nutrient Demand Along a Pond Hydroperiod Gradient (2021), Ecosystems. Implementations in other papers (listed below) may differ.

1. Pond-level nutrient demand measurements
   Collected nutrient uptake measurements from two compartments within ponds. First compartment included demand by water column and benthic substrates. Paired open-bottom clear plastic cylinders (12.5 cm diameter, 1 mm wall thickness) were gently pressed into benthic substrates in 3-4 locations without sedge around each pond. Cylinder water depth was measured to calculate volume and estimate nutrient addition required to increase concentrations 7-10× above ambient. Added 100 mg/L NH₄-N and PO₄-P solutions made from NH₄Cl and Na₂HPO₄.
   Quantities: 12.5 cm diameter cylinders, 1 mm wall thickness, 3-4 locations per pond, 7-10× above ambient nutrient additions, 100 mg/L NH₄-N and PO₄-P solutionsDuration: Single measurements per locationConditions: Areas without sedge vegetation selected
   Equipment: clear plastic cylinders, NH₄Cl, Na₂HPO₄, meter stick
2. Sedge biofilm demand measurements
   Second compartment included nutrient demand by microbial biofilms growing on submerged sedge (Carex aquatilis) in littoral zone. Small amounts of submerged, senesced sedge (<10 g) were transferred to plastic bags, and water samples were collected prior to and immediately after adding nutrients to increase concentrations 7-10× above ambient. Uptake calculated as decline in concentration during incubation divided by sedge mass (ug N or P g sedge⁻¹ d⁻¹).
   Quantities: Less than 10 g senesced sedge per sample, 7-10× ambient nutrient additionsDuration: Immediate before/after measurementsConditions: Submerged senesced sedge in littoral zone

Typical Equipment

• clear plastic cylinders
• plastic bags
• NH₄Cl
• Na₂HPO₄

Output Measurements

• benthic substrate uptake rate
• sedge biofilm uptake rate

Papers Using This Protocol (2)

Species Studied With This Protocol