DOI: 10.5061/dryad.m37pvmd7t
title: The dynamic matrix predicts population response to long-term experimental forest fragmentation

description: Context   Earth's forests are fragmented. Species'
 long-term persistence depends on their conservation in fragmented
 landscapes with remnants embedded in a matrix of human land use. This
 matrix influences species' persistence in fragments by determining
 their degree of isolation and the extent to which edge effects alter
 habitat. Matrix habitat is often dynamic, so its impact on persistence of
 remnant species changes over time.   Objectives  
 Previous research showed that the abundance response of predatory beetle
 species to matrix habitat predicted their response in fragments with a
 log-response ratio of about 0.5. When abundance declined in the matrix,
 there was a smaller but predictable decline in fragments. However, the
 predictive utility of a fragment:matrix log-response ratio needs testing
 with functionally different species, more detailed data, and a focus on
 mechanism.   Methods   In the Wog Wog habitat
 fragmentation experiment, we follow a detritivorous amphipod 27 years
 after forest fragmentation.   Results   The
 amphipod's response in habitat fragments was predicted by its
 response in the matrix with a log-response ratio of about 0.5, similar to
 predatory beetles. The amphipod's response was explained by its
 abiotic niche. The amphipod's short-term response did not predict its
 long-term response.   Conclusions   The log-response
 ratio might generalize across the invertebrate food web. For two groups
 within the Wog Wog experiment, a species' dynamic response in matrix
 habitat predicted its persistence in fragments. Future work should explore
 the generality of this finding. With knowledge of projected land use of
 matrix habitat, a species' matrix response could be used for
 management planning.
description: Invertebrates were sampled four times per year from 1985 to 1998,
 once during each season, November (spring), February (summer), May
 (autumn), and June (winter), and three times per year from 2009 to 2014
 (each season excluding winter). Pitfall traps were opened for seven days
 during each sampling period. Traps were 8.5 cm diameter, 475 ml plastic
 cups filled with a 150 ml solution of 75% ethanol (95%), and 25% glycol.
 Samples for the two traps at each monitoring site were pooled. Amphipods
 were identified and counted in the laboratory.
description: "Amphipod yr 3-29 by year.csv" all data by year # Site: 1-188
 (pitfall traps are located at sites, unit at which samples are taken)
 #rep: 1-6 (spatial random effect: replicates of the experiment) #size:
 1=small, 2=medium, 3=large, 4=control, NA=matrix (fragment size) #edge:
 1=core, 2=edge, 3=control, NA=matrix (proximity to fragment edge) #topo:
 1=slope, 2=drain (topography which determines vegetation communities)
 #treat: 1=frag, 2=control, 3=matrix (the experimental treatment
 fragmentation) #patch: 1-30 (spatial random effect: fragment/patch-level)
 BeforeFrag\_abun: Amphipod abundance before fragmenation (abundances
 summed for first two years of the experiment before the treatment was
 applied) LnBefFrag+1: Ln(amphipod abundance +1) before fragmenation #yr3
 amphipod abundance in year 3 #yr4 amphipod abundance in year 4 #yr5
 amphipod abundance in year 5 #yr6 amphipod abundance in year 6 #yr7
 amphipod abundance in year 7 #yr8 amphipod abundance in year 8 #yr9
 amphipod abundance in year 9 #yr10 amphipod abundance in year 10 #yr11
 amphipod abundance in year 11 #yr12 amphipod abundance in year 12 #yr13
 amphipod abundance in year 13 #yr14 amphipod abundance in year 14 #yr25
 amphipod abundance in year 25 #yr26 amphipod abundance in year 26 #yr27
 amphipod abundance in year 27 #yr28 amphipod abundance in year 28 #yr29
 amphipod abundance in year 29 NA for "size" and "edge"
 means not applicable because there are no patch sizes or edge in the
 continuous forest control plots NA for "BeforeFrag_abun" and
 "LnBef" not applicable because there was no matrix before
 fragmentation so no data were collected "Amphipod yr 3-29 three time
 blocks.csv" as analysed in the paper # Site: 1-188 (pitfall traps are
 located at sites, unit at which samples are taken) #rep: 1-6 (spatial
 random effect: replicates of the experiment) #size: 1=small, 2=medium,
 3=large, 4=control, NA=matrix (fragment size) #edge: 1=core, 2=edge,
 3=control, NA=matrix (proximity to fragment edge) #topo: 1=slope, 2=drain
 (topography which determines vegetation communities) #treat: 1=frag,
 2=control, 3=matrix (the experimental treatment fragmentation) #patch:
 1-30 (spatial random effect: fragment/patch-level) BeforeFrag\_abun:
 Amphipod abundance before fragmenation (abundances summed for first two
 years of the experiment before the treatment was applied) LnBefFrag+1:
 Ln(amphipod abundance +1) before fragmenation Yr3-7\_sum: Amphipod
 abundance summed for years 3-7 of the experiment Yr10-14\_sum: Amphipod
 abundance summed for years 10-14 of the experiment Yr25-29\_sum: Amphipod
 abundance summed for years 5-29 of the experiment NA for "size"
 and "edge" means not applicable because there are no patch sizes
 or edge in the continuous forest control plots NA for
 "BeforeFrag_abun" and "LnBefFrag+1" not applicable
 because there was no matrix before fragmentation so no data were collected