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Introduction

Methods

Results

Cover Type Effect

Age Effect

Additional Work

Discussion

Literature Cited

Age Effect, Species Richness Comparisons:

Within the 2 year old edge sites there was a clear separation between the edge treatment and the intact and clear-cut treatments when compared at approximately 180 individuals (Figure 1). The edge treatment had the highest species richness, whereas the clear-cut and intact forest treatments had lower species richness (Figure 1).

The eight year old edge sites exhibited greater separation between the treatments with the edge again having the highest species richness, followed by the clear-cut and intact forest treatments when compared at approximately 40 individuals (Figure 2). The abundance within the eight year old sites was low as the accumulation curves did not reach a plateau in the analysis (Figure 2).

Within the 15 year old sites we see a homogenization between all of the treatments as they achieve the same species richness when compared at approximately 85 individuals (Figure 3). The clear-cut treatment had substantially greater abundance in comparison to the other treatments in this age category (Figure 3).

Figure 1: Individual based rarefaction comparing estimated species richness between the clear-cut, edge (0 meter), and inact (105 meter) treatments within 2 year old edges. Black arrows represent common abundance to all treatments where comparisons should be made.

Figure 3: Individual based rarefaction comparing estimated species richness between the clear-cut, edge (0 meter), and inact (105 meter) treatments within 15 year old edges. Black arrows represent common abundance to all treatments where comparisons should be made.

Figure 2: Individual based rarefaction comparing estimated species richness between the clear-cut, edge (0 meter), and inact (105 meter) treatments within 8 year old edges. Black arrows represent common abundance to all treatments where comparisons should be made.

Age Effect, Multivariate Comparisons:

The NCAP analysis produced significant relationships for the community change along the edge gradient in all of the edge ages studied(Table 1). The analysis showed a dramatic change in the community composition along the 2 year old edge gradient near the zero meter treatment (Figure 2). In addition, the analysis predicted that the ground beetle community was 90% similar to the intact forest sites at an edge depth of 1.26 meters with a 95% confidence interval of (0.51m- 46.94m) (Table 1).

We see a similar pattern of change in community composition within the 8 year old edge sites with the shift in composition occurring close to the zero meter treatment (Figure 3). The analysis predicted that the ground beetle community was 90% similar to the intact forest sites at and edge depth of 2.32 meters with a much smaller 95% confidence interval of (0.68m- 3.45m) (Table 1).

A very different pattern of change in community composition along the edge gradient was observed in the 15 year old edge (Figure 4). Here we see a gradual change in community composition along the edge gradient and a more linear shape to the change in community composition (Figure 4). The analysis predicted that the community was 90% similar to the intact forest at an edge depth of 68.23 meters, with a 95% confidence interval of (1.73m- 105m) (Table 1).

Table 1: Summary of results from the NCAP analysis using a logistic function. Edge extent was predicted by model, with p-value calculated through monte-carlo analysis.

Figure 4: Comparison of community composition (gradient index) to the distance along the edge transect within a 2 year old forest edge.

Figure 5: Comparison of community composition (gradient index) to the distance along the edge transect within an 8 year old forest edge.

Figure 6: Comparison of community composition (gradient index) to the distance along the edge transect within a 15 year old forest edge.