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CHAPTER 6
OVERALL CONCLUSIONS
Due to the lack of photosynthetic primary production and limited surface connectivity
that reduces the quantity and quality of detrital inputs (e.g. leaves, wood, and dissolved organic
carbon), cave ecosystems have been considered energy-limited. The perception of energy
limitation is at the very core of conceptual models describing the trophic dynamics, community
structure, and evolutionary processes in cave ecosystems (Culver et al. 1995; Graening and
Brown 2003; Simon et al. 2007). However, the energy dynamics within and among cave
ecosystems have traditionally been described qualitatively and have rarely been quantified and
correlated with population-, community-, or ecosystem-level processes (but see Simon &
Benfield 2001, 2002; Cooney & Simon 2009; Huntsman et al., 2011a, b), which has hindered the
development of quantitative models describing how energy availability influences cave
ecosystem processes. This limited body of knowledge on cave ecosystem energy dynamics is in
stark contrast to that of surface ecosystems, in which numerous studies have described how the
quantity, quality, and type of detrital inputs influence both ecosystem processes and the structure
of micro-, meio-, and macro-faunal communities (see Moore et al. 2004). This dissertation
begins to close this knowledge gap by exploring how energy availability influences cave
ecosystem processes at multiple organizational levels (e.g., ecosystem-, community-, and
population-level) and time scales (e.g., ecological vs. evolutionary).
Chapter Two explored the relationships among organic matter biomass,
macroinvertebrate community structure and litter breakdown rates. Organic matter biomass
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