Fire Frequency and Community Heterogeneity in Tallgrass Prairie Vegetation

Biomass–Diversity Responses and Spatial Dependencies in Disturbed Tallgrass Prairies

“…This model describes a quadratic relationship between the size of disturbance relative to the total area and the community heterogeneity. According to Collins (1992), our results show this relationship for all N treatments, though the full unimodal response seems to appear at intermediate frequencies of disturbance. Thus, there is also a frequencydependent effect of fire.…”

“…To compute biomass-diversity relationships, we assumed the existence of strong postitive correlations between patch heterogeneity and species richness, as has been previously reported in tallgrass prairies (Collins, 1992). We have considered the existence of gaps when B t ðiÞo 50 gm À2 : Although this choice may look arbitrary, it is intended to represent some maximum light availability index below which non-dominant species may appear.…”

“…number of neighboring cells pertaining to some gap) would account for some species-specific habitat availability. Significant positive spatial heterogeneity-species richness relationships have been formerly found in the Konza prairie by Collins (1992). Gap area entropy H t at any time was defined with the classical Shannon's index of diversity as…”

Common Methods for Tallgrass Prairie Restoration and Their Potential Effects on Bee Diversity

“…This revealed that fire frequency was dependent on the age of the restoration, with some managers using fire yearly during the creation and establishment of a site and then every 2-4 years for maintenance (see Table 3). The majority of prescribed burning was reported to occur during winter and early spring when bees are largely inactive, but the timing and frequency of burns seem to have a significant effect on plant diversity and community heterogeneity (Collins 1992;Bowles and Jones 2013), with regular burnings increasing prairie diversity. However, some managers mentioned that spring burns, conducted by almost 62% of managers, shifted the community to be grass dominated, which could significantly affect bee communities by decreasing plant availability.…”

Quantifying scales of spatial variability in algal turf assemblages on coral reefs

“…However, the effects of grazing are widely variable at scales ranging from meters (Iveša et al 2010, Poray & Carpenter 2014 to local (Fletcher 1987) and regional scales (Foster 1990). Disturbance has long been known to play a major role in driving variability among communities separated by several meters in the rocky intertidal and subtidal habitats (Sousa 1979, Smale et al 2010, and large-scale disturbances such as storms, fires, or El Niño events can create heterogeneity over a scale of 10s or 100s of meters (Kennelly 1987, Collins 1992, Dayton et al 1992. Propagule dispersal and recruitment contribute to community heterogeneity at both small (meters) (Andrew & Viejo 1998) and very large (100s of kilometers) spatial scales (Deysher & Norton 1981), depending on the type of reproduction (Bellgrove et al 2004).…”