Leaf pack decomposition assay

Knowledge graph centered on Leaf pack decomposition assay with 71 nodes and 129 connections. Top connected: Bacteria, aquatic insects, Ambystoma tigrinum, Picea engelmannii, Trichoptera.

Method synopsis

Controlled microcosm experiments measuring invertebrate-mediated breakdown of sedge detritus by quantifying mass loss of coarse and fine particulate organic matter over time. Uses standardized biomass densities and compares to no-invertebrate controls.

Synthesized from method descriptions across 11 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 — Species-specific traits predict whole-assemblage detritus processing by pond invertebrates (2022), Oecologia. The protocol was originally introduced by From brown to green: how does caddisfly detritus processing affect the growth of invertebrate algal grazers (2009). Implementations in other papers (listed below) may differ.

1. Collect sedge detritus
   Carex aquatilis sedge was collected from montane kettle-pond wetlands near the USFS trail #401 south of the RMBL. Sedge was air-dried for 72-96 hours, then 20-25 g was added to each microcosm along with 9 L pond water.
   Quantities: 20-25 g sedge per microcosm, 9 L pond water per microcosmDuration: 72-96 hours air-drying timeConditions: Mid-summer collection (late June through early August), montane elevation (2850 m)
   Equipment: plastic bins
2. Prepare microbial inoculum
   Microbial inoculum was collected by scrubbing submerged rocks, wood, and sedge from source ponds. All microcosms received equal volume aliquots of filtered microbial inoculum with a 1 mm mesh and were incubated for 4-5 days to encourage biofilm growth on re-hydrated sedge.
   Quantities: Equal volume aliquots per microcosm, 1 mm mesh filtrationDuration: 4-5 days incubation periodConditions: Before adding invertebrates
   Equipment: 1 mm mesh, scrubbing tools
3. Add invertebrates to treatments
   Invertebrates were collected from nearby ponds and added to microcosms. A treatment with Limnephilus externus was included as a reference in all experiments because it was the most common caddisfly species. The microcosm density of L. externus corresponded to the inflection point (100 individuals/m²) of an asymptotic detritus processing response. Similar densities were used when stocking caddisfly species with 5th (final) instar masses comparable to L. externus, but proportionally greater densities were used for taxa with smaller final instars.

Typical Equipment

• plastic bins
• 1 mm mesh
• 1 mm net or sieve
• drying oven
• balance

Output Measurements

• CPOM processing rate
• FPOM processing rate
• mass-specific processing
• per-capita processing

Papers Using This Protocol (11)

Species Studied With This Protocol