@article {BF-2413, title = {Patch-Occupancy Modeling as a Method for Monitoring Changes in Forest Floristics: a Case Study in Southeastern Australia}, journal = {Conservation Biology}, volume = {23}, year = {2009}, month = {06/2009}, pages = {740 - 749}, abstract = {The ability to monitor changes in biodiversity is fundamental to demonstrating sustainable management practices of natural resources. Disturbance studies generally focus on responses at the plot scale, whereas landscape-scale responses are directly relevant to the development of sustainable forest management. Modeling changes in occupancy is one way to monitor landscape-scale responses. We used understory vegetation data collected over 16 years from a long-term study site in southeastern Australia. The site was subject to timber harvesting and frequent prescribed burning. We used occupancy models to examine the impacts of these disturbances on the distribution of 50 species of plants during the study. Timber harvesting influenced the distribution of 9 species, but these effects of harvesting were generally lost within 14 years. Repeated prescribed fire affected 22 species, but the heterogeneity of the burns reduced the predicted negative effects. Twenty-two species decreased over time independent of treatment, and only 5 species increased over time. These changes probably represent a natural response to a wildfire that occurred in 1973, 13 years before the study began. Occupancy modeling is a useful and flexible technique for analyzing monitoring data and it may also be suitable for inclusion within an adaptive-management framework for forest management.}, doi = {10.1111/j.1523-1739.2008.01146.x}, author = {Trent Penman and Binns, Doug L. and Kavanagh, Rodney P.} } @article {BF-2387, title = {Quantifying successional changes in response to forest disturbances}, journal = {Applied Vegetation Science}, volume = {11}, year = {2009}, month = {04/2008}, pages = {261 - 268}, abstract = {Question: Can dissimilarity measures of individual plots be used to forecast the driving factors among various anthropogenic disturbances influencing understorey successional changes? Location: Yambulla State Forest, south-eastern Australia (37{\textdegree}14{\textquoteright}S, 149{\textdegree}38{\textquoteright}E). Methods: Assessments of understorey vegetation communities were taken prior to anthropogenic disturbances and at three subsequent time periods representing a period of 15 years post-disturbance. Dissimilarities were calculated from the original assessment and modelled in a Bayesian framework to examine the influence of logging, number of prescribed burns and time. Results: All sites underwent significant changes over time independently of the imposed management regimes. Logging resulted in an immediate change in vegetation assemblage which decreased in the subsequent assessments. The number of prescribed fires brought greater change in the shrub vegetation assemblages, but less change in the ground species vegetation assemblages. Conclusions: The anthropogenic disturbances did have some role in the changes of vegetation assemblages but these were minimal. The ongoing changes appear to be a natural response to the last wildfire, which passed through the study area in 1973 (13 years prior to the study). Forest management practices should consider the influence of wildfire succession when planning for the conservation of biodiversity.}, issn = {14022001}, doi = {10.3170/2008-7-18424}, author = {Trent Penman and Binns, Doug L. and Kavanagh, Rodney P.} } @article {BF-2388, title = {Changes in understorey plant species richness following logging and prescribed burning in shrubby dry sclerophyll forests of south-eastern Australia}, journal = {Austral Ecology}, volume = {33}, year = {2008}, month = {04/2008}, pages = {197 - 210}, abstract = {The impacts of prescribed burning and timber harvesting on species diversity have been the subject of considerable debate. The temporal and spatial scale of these disturbances often presents major limitations to many studies. Here we present the medium-term results of a planned long-term study examining the impacts of logging and prescribed burning on the understorey floristic richness in shrubby dry sclerophyll forest in the south-east of New South Wales, Australia. Generalized estimating equations were used to model the effect of environmental factors and disturbance variables on species richness at the coupe (\~{}30 ha) and plot (\~{}0.01 ha) scale. At the plot scale, fire effects on separate components of the vegetation were broadly consistent with other studies, with frequent fire resulting in a relative increase of species richness for species less than 1 m in height and a decline of larger species taller than this height. At the coupe scale, there was no decline in richness of larger shrub species, possibly owing to the spatial heterogeneity of fire frequency at this scale. Logging resulted in significantly greater species richness in the shrub layer, but had no significant effect on species richness in the ground layer. During the study period, there was a general decline in plant species richness at both coupe and plot scales which occurred independently of imposed management regimes. This is thought to be related to a natural succession following wildfire, and may be due to the absence of high-intensity fire in the study area since 1973, or to an effect related to season of burning.}, doi = {10.1111/j.1442-9993.2007.01809.x}, author = {Trent Penman and Binns, Doug L. and Shiels, RJ and Allen, RM and Kavanagh, Rodney P.} } @article {BF-2368, title = {Patchiness of prescribed burns in dry sclerophyll eucalypt forests in South-eastern Australia}, journal = {Forest Ecology and Management}, volume = {252}, year = {2007}, month = {11/2007}, pages = {24 - 32}, abstract = {Prescribed burning is commonly used in eucalypt forests to reduce fire risk and minimize damage to people and property in the event of a wildfire. The dry sclerophyll forests of south-eastern Australia are naturally fire-prone. Little is known about the heterogeneity of prescribed fires in these forests. This paper reports on the spatial variability of repeated low intensity fires under two burning regimes, in both logged and unlogged forests, for a 17-year period from 1988 to 2005. Prescribed burns were extremely patchy at both the coupe and the plot scale for all treatments. Burns implemented soon after logging covered significantly greater areas than the standard prescribed burns. On the coupe scale, the extent of the burn was influenced by the average aspect of the coupe and the percent of the coupe burnt in the last fire. At the smaller plot scale, the extent of the burn was influenced by the neighbourhood burn patterns, the distance the plot was from the nearest drainage line, the time since the last fire and the percentage of the plot that was burnt in the last fire. Under operational conditions, sites on ridges are likely to burn approximately every 11 years and sites in gullies approximately every 20 years. Patchy burns achieved in this study will provide refuges for fire sensitive species and newly burnt areas for colonizing species and are therefore likely to have significantly lower ecological impacts than homogenous burns.}, doi = {10.1016/j.foreco.2007.06.004}, author = {Trent Penman and Kavanagh, Rodney P. and Binns, Doug L. and Melick, DR} }