@article {KNZ001953,
	title = {A comprehensive approach to analyzing community dynamics using rank abundance curves},
	journal = {Ecosphere},
	volume = {10},
	year = {2019},
	pages = {e02881},
	abstract = {<p>Univariate and multivariate methods are commonly used to explore the spatial and temporaldynamics of ecological communities, but each has limitations, including oversimplification or abstractionof communities. Rank abundance curves (RACs) potentially integrate these existing methodologies bydetailing species-level community changes. Here, we had three goals:first, to simplify analysis of commu-nity dynamics by developing a coordinated set of R functions, and second, to demystify the relationshipsamong univariate, multivariate, and RACs measures, and examine how each is influenced by the commu-nity parameters as well as data collection methods. We developed new functions for studying temporalchanges and spatial differences in RACs in an update to the R package library(\&ldquo;codyn\&rdquo;), alongside othernew functions to calculate univariate and multivariate measures of community dynamics. We also devel-oped a new approach to studying changes in the shape of RAC curves. The R package update presentedhere increases the accessibility of univariate and multivariate measures of community change over timeand difference over space. Next, we use simulated and real data to assess the RAC and multivariate mea-sures that are output from our new functions, studying (1) if they are influenced by species richness andevenness, temporal turnover, and spatial variability and (2) how the measures are related to each other.Lastly, we explore the use of the measures with an example from a long-term nutrient addition experiment.Wefind that the RAC and multivariate measures are not sensitive to species richness and evenness andthat all the measures detail unique aspects of temporal change or spatial differences. We alsofind that spe-cies reordering is the strongest correlate of a multivariate measure of compositional change and explainsmost community change observed in long-term nutrient addition experiment. Overall, we show that spe-cies reordering is potentially an understudied determinant of community changes over time or differencesbetween treatments. The functions developed here should enhance the use of RACs to further explore thedynamics of ecological communities.</p>},
	keywords = {LTER-KNZ},
	doi = {10.1002/ecs2.2881},
	url = {https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.2881},
	author = {M.L. Avolio and Carroll, I. and Scott. L. Collins and Houseman, Gregory R. and Hallett, L.M. and Isbell, F.L. and Koerner, S.E. and Kimberly J. Komatsu and M.D. Smith and K.R. Wilcox}
}
@article {KNZ001808,
	title = {The interactive effects of press/pulse intensity and duration on regime shifts at multiple scales},
	journal = {Ecological Monographs},
	volume = {87},
	year = {2017},
	pages = {198-218},
	abstract = {<p>Regime shifts are difficult to reverse transitions that occur when an ecosystem reorganizes around a new set of self-reinforcing feedbacks. Regime shifts are predicted to occur when the intensity of some exogenous driver variable\&mdash;such as temperature, annual harvest rate or nutrient addition rate\&mdash;gradually approaches and crosses a threshold value, initiating a transition to an alternative state. However, many driver variables now change rapidly as presses or pulses, not gradually, requiring new conceptual frameworks for understanding and predicting regime shifts. We argue that identifying and controlling regime shifts in response to presses and pulses will require a greater focus on the duration, not just intensity, of changes in driver variables. In ecosystems with slower dynamics, transitions to an alternative state can take years to decades and as a result, a driver press with an intensity capable of resulting in a regime shift over long time-spans may fail to cause a regime shift when applied for shorter durations. We illustrate these ideas using simulations of local-scale alternative stable state models and preliminary evidence from long-term grazing and eutrophication experiments. The simulations also suggest that small changes in the duration of driver presses or pulses can determine whether an ecosystem recovers to its original state. These insights may extend to larger scales. In spatially extended simulations that included patchiness, spatial heterogeneity, and spatial connectivity, all patches recovered to their original state after shorter presses. However, once press duration exceeded a threshold, growing proportions of the landscape shifted to an alternative state as press duration increased. We observed similar patchy transitions in a catchment-scale experiment that reinstated frequent fires approximately halfway through a regime shift from grassland to shrubland, initiated by fire suppression. In both the local- and larger-scale models, the threshold duration needed to elicit regime shifts decreased as press intensity increased or when factors counteracting regime shifts weakened. These multiple lines of evidence suggest that conceptualizing regime shifts as an interactive function of the intensity and duration of driver changes will increase understanding of the varying effects of driver presses, pulses, and cycles on ecosystem dynamics.</p>},
	keywords = {LTER-KNZ},
	doi = {10.1002/ecm.1249},
	url = {https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/ecm.1249},
	author = {Z. Ratajczak and D{\textquoteright}Odorico, Paolo and Scott. L. Collins and B.T. Bestelmeyer and Isbell, F.L. and Jesse B. Nippert}
}
