Terrestrial cellulose decomposition

3.3.3.1 Field protocol

In the 2007-2008 summer, cotton strip assays were used to test the rate of cellulose decomposition in the riparian zone, as a surrogate for leaf decomposition (Boulton and Quinn 2000). Although Tiegs et al. (2007) showed that cellulose strip decomposition did not always correlate strongly with leaf decomposition, they suggested that it was appropriate

for comparing decomposition between sites, but may be more indicati of microbial activity than invertebrate feeding activity. This technique also avoided a number of logistic issues relating to the number of leaf species that would need to be quantified, and the difficulty of testing the small leaves of the prevalent r

All trials used 35 mm x 60 mm strips of unbleached cretonne EMPA 222 test fabric (EMPA Testmaterials: St Galen).

surface was tested with single cotton strips, each stapled 120mm x 7mm mesh strip of

Mitre 10 Australia Ltd). The free end of each strip was nailed to the ground beside a turf mat (

with the ground surface

nailing 3 control strips in place at each site, then immediately each strip and sealing

Fig.3.7 Surface cotton strips (inset) were held against the ground surface beside the sediment mats with the steel nail

Decomposition in the humic soil layer was tested by attaching paired cotton strips to each side of a 40mm x 70mm strip of gut

steel staples (Figure 3.8

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for comparing decomposition between sites, but may be more indicati of microbial activity than invertebrate feeding activity. This technique also avoided a number of logistic issues relating to the number of leaf species that would need to be quantified, and the difficulty of testing the small leaves of the prevalent riparian species.

All trials used 35 mm x 60 mm strips of unbleached cretonne EMPA 222 test fabric (EMPA Testmaterials: St Galen). Decomposition

with single cotton strips, each stapled to a 40mm x strip of lightweight PVC gutter mesh (Buy Right™, Australia Ltd). The free end of each strip was nailed to the ground beside a turf mat (n = 9) at each site, with the cotton in contact with the ground surface (Fig. 3.7). Handling effects were assessed by

ailing 3 control strips in place at each site, then immediately and sealing it in an individual ziplock bag.

Surface cotton strips (inset) were held against the ground surface beside the sediment mats with the steel nail securing the mat.

Decomposition in the humic soil layer was tested by attaching paired cotton strips to each side of a 40mm x 70mm strip of gutter mesh with

3.8). These were deployed beside the turf mats

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for comparing decomposition between sites, but may be more indicative of microbial activity than invertebrate feeding activity. This technique also avoided a number of logistic issues relating to the number of leaf species that would need to be quantified, and the difficulty of testing the

All trials used 35 mm x 60 mm strips of unbleached cretonne EMPA 222 ecomposition on the soil

to a 40mm x ghtweight PVC gutter mesh (Buy Right™, Australia Ltd). The free end of each strip was nailed to the

, with the cotton in contact ). Handling effects were assessed by ailing 3 control strips in place at each site, then immediately removing

Surface cotton strips (inset) were held against the ground surface beside

Decomposition in the humic soil layer was tested by attaching paired ter mesh with beside the turf mats (n

= 9) in the riparian zone at each site. Each paired strip (hereafter ‘panel’) was inserted lengthwise

was compressed against the strip control panels were buried at each site assess handling effects.

Fig.3.8 Paired cotton strips were attached to either side of mesh panels and inserted vertically into the topsoil.

3.3.3.2 Laboratory protocol

At the upstream Macquarie site, CB, o panel were lost to overbank flow

strips were retrieved after 40 days and

Tensile strength was measured with a tensiometer (University of

Tasmania, Australia) incorporating a Salter Electro Samson scale (Kent, UK).

The tensile strength (kg) strip into the 40 mm jaws breaking point of the resultant

strength loss (CTSL) was calculated by subtracting the strength of

exposed strips from the strength of controls. Because the paired buried strips were pseudo-repl

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9) in the riparian zone at each site. Each paired strip (hereafter ‘panel’) lengthwise into a 60 mm deep slot in the soil,

d against the strip with a stainless steel trowel

panels were buried at each site and then retrieved immediately assess handling effects.

Paired cotton strips were attached to either side of mesh panels and into the topsoil.

3.3.3.2 Laboratory protocol

At the upstream Macquarie site, CB, one surface strip and one buried overbank flow on about day 13. All the remaining strips were retrieved after 40 days and air-dried at room temperature. Tensile strength was measured with a tensiometer (University of

Tasmania, Australia) incorporating a Salter Electro Samson scale (Kent,

tensile strength (kg) of the cotton was determined by fastening each 40 mm jaws of the tensiometer, and recorded as the

resultant 35 x 40 mm strip. Cotton tensile strength loss (CTSL) was calculated by subtracting the strength of

exposed strips from the strength of controls. Because the paired buried replicated, the mean CTSL of the 2 strips was

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9) in the riparian zone at each site. Each paired strip (hereafter ‘panel’) into a 60 mm deep slot in the soil, and the soil

with a stainless steel trowel. Three and then retrieved immediately to

Paired cotton strips were attached to either side of mesh panels and

ne surface strip and one buried remaining dried at room temperature. Tensile strength was measured with a tensiometer (University of

Tasmania, Australia) incorporating a Salter Electro Samson scale (Kent,

was determined by fastening each recorded as the

35 x 40 mm strip. Cotton tensile strength loss (CTSL) was calculated by subtracting the strength of

exposed strips from the strength of controls. Because the paired buried icated, the mean CTSL of the 2 strips was

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calculated. Data analysis used the nlme package (Pinheiro et al. 2009) in R 2.11.0 (R Development Core Team 2010). The influence of soil

physicochemical variables on cotton strip strength loss was tested using Pearsons correlation coefficient.