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Locations of the northern populations in Gatineau Park (Ottawa valley, southern Québec) and of the southern populations in Pinery Provincial Park (southern Ontario), within the North American distributions (inset) of Helianthus divaricatus (based on Heiser et al. 1969) and of Rhus aromatica (based on Barkley 1937 and Soper & Heimburger 1982).
Source publication
1 The clonal perennial herb Helianthus divaricatus and the clonal shrub Rhus aromatica reach the northern limit of their distribution in southern Québec (Canada), where both are rare, but they are more common southwards in the adjacent province of Ontario. We tested whether peripheral populations of these species maintain themselves by having highl...
Contexts in source publication
Context 1
... northern location was on the limit of both spe- cies' distribution range, whereas the southern loca- tion was clearly within but not necessarily at the geographical centre of the species' ranges (Fig. 1). However, the distribution of forest vegetation types suggests that bioclimatic conditions in southern Ontario are similar to those in the Carolinian type of forest (Allen et al. 1990), near the centre of both species' ranges, but dier from those of southern Que bec. Thus, trees such as Juglans nigra, Liriodendron tulipifera, ...
Context 2
... in temperatures occurring dur- ing winter, than the southern site and, by implication, the centre of the species' range (Canadian Climate Program 1993). Ouellet & Sherk (1967) de®ned a number of plant hardiness zones according to minimum winter temperatures and length of the frost-free period, and the two sites were separated by four such zones. (Fig. 1) and are referred to as northern-1 and northern-2. These populations were separated by about 10 km and grew in similar open red oak (Quercus rubra) and white oak (Q. alba) forests, on south facing slopes of the Precambian Shield ( Gagnon & Bouchard 1981;Gagnon 1985). The soil is a dystric brunisol that has developed on a thin, sandy ...
Citations
... Species performance has been extensively studied along a geographical and ecological centre-periphery gradient, focusing on the current distribution of the focal species (e.g. Carey et al., 1995;Nantel and Gagnon, 1999;Jump and Woodward, 2003;Costa et al., 2016), and on the current ecological environment, more recently based on ecological niche modelling Downloaded from https://academic.oup.com/aob/article/127/7/943/6152872 by guest on 21 March 2023 (ENM) (e.g. Martínez-Meyer et al., 2013;Weber et al., 2017;Osorio-Olvera et al., 2019). ...
Background and Aims
The Centre–Periphery Hypothesis posits that higher species performance is expected in geographic and ecological centres rather than in peripheral populations. However, this is not the commonly found pattern; therefore, alternative approaches, including the historical dimension of species geographical ranges should be explored. Morphological functional traits are fundamental determinants of species performance, commonly related to environmental stability and productivity. We tested whether or not historical processes may have shaped variations in tree and leaf traits of the Chaco tree Bulnesia sarmientoi.
Methods
Morphological variation patterns were analysed from three centre-periphery approaches: geographical, ecological and historical. Tree (stem and canopy) and leaf (leaf size and specific leaf area) traits were measured in 24 populations across the species range. A Principal Component Analysis was performed on morphological traits to obtain synthetic variables. Linear Mixed-Effects Models were used to test which of the implemented centre-periphery approaches significantly explained trait spatial patterns.
Key Results
The patterns retrieved from the three centre-periphery approaches were not concordant. The historical approach revealed that trees were shorter in center populations than in the periphery. Significant differences in leaf traits were observed between the geographical centre and the periphery, mainly due to low specific leaf area values towards the geographical centre. We did not find any pattern associated with the ecological centre-periphery approach.
Conclusions
The decoupled response between leaf and tree traits suggests that these sets of traits respond differently to processes occurring at different times. The geographical and historical approaches showed centres with extreme environments in relation to their respective peripheries, but the historical centre has also been a climatically stable area since the Last Glacial Maximum. The historical approach allowed for the recovery of historical processes underlying tree traits variation, highlighting that centre-periphery delimitations should be based on a multi-approach framework.
... Due to the complex interactions between demographic processes, biotic interactions and abiotic conditions, we so far have a very limited understanding of how the environmental context shapes plant recruitment across species distributional ranges 13 . Identifying the limitations and bottlenecks in the demographic processes of plant recruitment across species' distributional ranges is, however, key for projecting future range dynamics of plants 14,15 . ...
Plant recruitment is a multi-stage process determining population dynamics and species distributions. Still, we have limited understanding of how the successive demographic processes depend on the environmental context across species’ distributional ranges. We conducted a large-scale transplant experiment to study recruitment of Pinus cembra over six years. We quantified the effects of environmental conditions on four demographic processes and identified the most limiting across and beyond the pines’ elevational range over several years. Realized transition probabilities of the demographic processes varied substantially across the species' distributional range. Seed deposition decreased from the lower to the upper elevational range margin by 90%, but this reduction was offset by increased seed germination and seedling survival. Dispersal limitation at the upper range margin potentially stems from unsuitable seed caching conditions for the animal seed disperser, whereas increased seed germination might result from enemy escape from fungal pathogens and favourable abiotic conditions at the upper range margin. Our multi-year experiment demonstrates that environmental context is decisive for the local relevance of particular demographic processes. We conclude that experimental studies identifying the limiting demographic processes controlling species distributions are key for projecting future range dynamics of plants.
... However, the ability of managers to provide a quality population for anglers is often difficult. Generally abiotic factors are largely considered to regulate Yellow Perch recruitment, growth, and survival (Nantel and Gagnon 1999). For example, abiotic factors such as the level of precipitation Ward et al. 2004), increased water level (Henderson 1985;Dembkowski et al. 2014), wind (Aalto and Newsome 1993;Fisher et al. 1996), and thermal regimes (Clady 1976;Longhenry et al. 2010;Kaemingk et al. 2014) have all been associated with variable Yellow Perch recruitment. ...
Much attention has been given to describing how abiotic factors impact the population dynamics of Yellow Perch Perca flavescens, especially during early life history; however, the impacts of biotic factors are less understood. In this study, we simplified the community assemblage to reduce interspecific competition and gain a better understanding of the role biotic conditions play in creating Yellow Perch fisheries. Yellow Perch were introduced into three recently renovated lakes in an attempt to increase growth rates through reduced interspecific competition and hypothetically allow fish to reach an acceptable size for angler harvest in a shorter period of time compared with four mixed‐species lakes. Yellow Perch‐only populations exhibited faster growth, potentially resulting from reduced interspecific competition, increased piscivory, and lower levels of activity. Yellow Perch‐only populations also had more consistent recruitment, onset of maturation at age 1, and an earlier onset of sexual size dimorphism compared with mixed‐species lakes and published literature. While limitations of density dependence were noted, natural resource managers are encouraged to investigate methods that would capitalize on the improved population dynamics of Yellow Perch‐only lakes and the release from biotic controls.
... larval settlement) is typically highly variable across the geographic range of fishes, particularly for species distributed along a latitudinal gradient (Compton et al., 2007), because of the metabolic effects of a gradient in water temperatures on fish growth and survival (Lek et al., 2012;Phillips et al., 2014;Pörtner and Knust, 2007;Wakefield et al., 2017). For this reason, species tend to have thermal restrictions on their distribution, with recruitment being generally low and sporadic towards both low and high temperature extremes of their distribution (Shepherd and Brook, 2007;Zacherl et al., 2003; but see Sagarin and Gaines, 2002;Sagarin et al., 2006), where local environmental conditions are often not optimal for recruit survival (Figueira and Booth, 2010;Jones, 1984;Nantel and Gagnon, 1999). ...
Distribution shifts of demersal fishes are important adaptive responses to warming oceans for species' persistence. Shifts are facilitated by factors such as adult movement and dispersal of pelagic larvae to normally cooler regions, where increasing ocean temperatures are now enhancing larval and juvenile survival. However, successful recruitment (i.e. larval settlement) at these new regions can be constrained by resource availability, specialisation (food, habitat) and ecological interactions (competition, predation). Evaluating the capacity or likelihood of a species to successfully shift or expand its range, provides information relevant to biodiversity conservation and fisheries management, and is particularly important for species with restricted ranges. Choerodon rubescens (Günther, 1862) is an exploited labrid endemic to ~ 1400 km of the west Australian coastline, encompassing 13° of latitude and a 6°C temperature gradient. This region recently experienced a rapid warming event of ~ 3°C, which lasted 3 months and mirrored ocean temperatures expected in the next 50 years. Following this event, high levels of recruitment of C. rubescens occurred towards its southern, cooler distribution limit. Juvenile abundances were surveyed in this study to evaluate: (1) the effect of elevated temperatures on recruitment success across shallow water habitats spanning the species' distribution, (2) temporal variation in recruitment success in the typically cooler, southern part of its range and (3) ecological characteristics important to recruit survival, including habitat preferences, diet and behaviour. Juvenile C. rubescens were significantly more abundant at the margin between reef and sand and towards the cooler southern range end. Reef margin habitat provides access to shelter from predators within the reef and to sand-associated invertebrate prey in adjacent soft sediments, where most feeding activity occurred. Juveniles were abundant (0.3 to 4 fish/40 m2) in reef margin habitats of the southern cooler region for three consecutive years, with individuals represented by multiple cohorts, indicating suitable environmental conditions for ongoing recruitment and survival. Juveniles at this habitat were able to compete effectively with other co-occurring labrids for invertebrate prey. As oceans warm, the number of recruits arriving and surviving beyond the existing cooler range limit will be dependent on factors such as successful spawning, larval delivery and survival, and availability of reef margin habitat with associated prey; these factors will determine the successful range shift or expansion of C. rubescens. We present an example of how range-wide spatiotemporal ecological studies of juvenile fish can identify range shift capacity and inform management adaptive to climate change.
... Larval and juvenile stages show particular dependence on temperature, especially towards the cooler range edge of a species where low winter temperatures can result in high mortality rates (Figueira et al. 2009). Recruitment is generally low and sporadic towards both low and high temperature extremes along a species' geographic range, because of the physiological limitations of temperature extremes on recruits (Nantel and Gagnon 1999;Zacherl et al. 2003). These patterns, however, are recently changing in response to warming oceans, with unusually high recruitment of tropical species into temperate locations, particularly along regions influenced by poleward boundary currents (Booth et al. 2007;Johnson et al. 2011;Last et al. 2011;Vergés et al. 2014). ...
... Finally, we used back-calculated juvenile ages to estimate the settlement time of juveniles surveyed and relate recruitment events to temperature profiles in the region. We hypothesised that: (a) abundance of adult C. rubescens would be higher towards the warmer northern end rather than the cooler southern end of their geographic range, due to the positive effects of temperature on metabolism (Kordas et al. 2011) and the strong temperature gradient along WA; (b) historical recruitment (inferred from length frequency data) would be low and sporadic towards both range edges (Nantel and Gagnon 1999;Zacherl et al. 2003), and (c) recruitment following the 2011 marine heat wave would be highest towards the cooler range end in response to warmer ocean temperatures. ...
Range shifts as a result of warming oceans call for evaluation of populations at the geographic range level, particularly for highly vulnerable species such as endemics and fisheries targets. We examined the influence of latitudinal temperature gradients and temperature anomalies during a 2011 marine heat wave on range-wide abundance, length frequency and recruitment of Choerodon rubescens, a reef associated fisheries target endemic to Western Australia. Diver-operated stereo-video surveys were conducted at shallow reefs (3–18 m) along 124 sites spanning the entire species’ distribution (21°S–34°S), to obtain abundance, length frequency and habitat data. Models were used to assess the influence of satellite-derived long-term average temperature (2002–2010) and 2011 temperature anomalies, compared to habitat, depth and distance to mainland, on the abundance of adult and juvenile fish and overall population size structure. Long-term temperature had the highest effect on adult C. rubescens abundance, with highest values recorded towards the centre of the temperature gradient investigated (22 °C). In contrast, juveniles were mostly influenced by 2011 temperature anomalies, with highest abundance recorded towards the cooler range edge, where anomalies were lowest. Length-frequency distributions showed recent recruitment towards the cooler range edge coupled with recruitment absence at the warmer edge. Recruitment differences were traced to 2011–2013 when ocean temperatures were up to 3.5 °C higher than average, via back-calculation of juvenile ages. These findings support predictions of a poleward distributional shift in response to ocean warming, and suggest that marine heatwaves can facilitate range shifts by affecting recruitment across latitudinal gradients.
... Previous studies have found a declining performance of plant populations (densities, growth rates, and fecundity), and increasing demographic fluctuations in the range edges compared to the center due to less suitable conditions and higher isolation (Brown 1984, Nantel and Gagnon 1999, Eckhart and Moeller 2011, whereas recent reports disagree with these predictions (Sagarin and Gaines 2002, Sexton et al. 2009, Villellas et al. 2013, Abeli et al. 2014, Aikens and Roach 2014. For example, Sagarin and Gaines (2002) found that only 39% of published studies supported the prediction that a higher population performance occurs in the center. ...
The upcoming climatic variability is expected to influence the population dynamics of tree
species, but few empirical studies have been performed over broad geographical scales, which may be
more convincing to address tree range shift under climate change. In the present study, the population
structure and regeneration dynamics of Quercus variabilis were investigated along latitudinal and longitudinal
gradients over its full range in China. The size structure, density, mortality rate (b), conversion rate
(CR), initial recruitment (y0), and survival from birth to the highest class of regeneration (survival rate
3 [SR]) were analyzed. The results showed the following: (1) The population structure of Q. variabilis exhibited
an inverse-J shape throughout the latitudinal gradient, and the relative seedling density was significantly
higher in the Middle populations than in the North and the South. In addition, the y0 and SR
exhibited the highest values in the middle, but no significant differences in the density and total basal area
of adults were found across latitudes. (2) Along the longitudinal gradient, an inverse-J-type population
structure was present in the West populations, but was not observed in the East due to the scarcity of
individuals in regenerated populations. The total basal area and density of adults were similar across
longitudes, but both the seedling density and the relative seedling density, along with the y0 and SR, were
higher in the Middle than in the East and the West. The b of adults was lower in the middle-longitude
populations than in the West and the East. (3) Climate (annual average temperature) was identified as
the primary factor affecting regeneration. In addition, local factors, including the soil and stand conditions,
were also found to play a significant role in determining the regeneration dynamics. Based on these results,
we speculate that populations of Q. variabilis at the range edges would decline in the context of climate
change, particularly in the South and the East.
... The comparison of the isotherms of the coldest month's mean temperature (°C) calculated for sea level [68] with the distribution of C. pulicaris in Pomerania and other regions of Poland [31] indicates a relationship between the species range boundary and the isotherm −2°C, while in the case of P. sylvatica with the isotherm −4°C. Some plant species at the limit of their range are prone to local extinctions [29,69]. Peripheral populations are frequently smaller than the populations at the center of the species range [70,71], and therefore they are more vulnerable to extinction, especially if they are isolated [20,29,72]. ...
This paper presents the distribution dynamics, soil and phytocoenotical conditions of the occurrence of Carex pulicaris and Pedicularis sylvatica at the margin of their range in NW Poland. Dynamic cartograms of these species were made on the basis of our field studies and available contemporary and historical records. The studies showed that the plants grow on organic hemic-muck soils, mucky soils and typical muckous soils. The occurrence of these two species on different types of soils proves that they are able to adapt easily to varying habitat conditions of post-bog areas. Populations of C. pulicaris and P. sylvatica were most frequently not numerous and occurred in small community patches. Analyzed phytocoenoses with C. pulicaris have been classified as the community of the alliance Caricion davallianae or the alliance Molinion . Phytocoenoses with P. sylvatica are represented by the association Nardo-Juncetum squarrosi and the community of the class Molinio-Arrhenatheretea . The distribution dynamics of these species shows that they are disappearing from some parts of this region, which proves the recessive trends. This process is more intensive for P. sylvatica , which should be included in the red list of Polish plants like C. pulicaris . The disappearance of the populations of both species has been caused by worsening habitat conditions (insufficient moisture, eutrophication), expansion of competitive plant species and land abandonment.
... Probability of population extinction increases as l decreases and the variance of l increases (Lande and Orzack, 1988;Lande, 1993). Only further study across several years and habitats will be able to determine whether the variability of the mixedgrass population growth rate is greater than the growth rate of tallgrass populations and is a contributing factor to the range limit and regional productivity of A. gerardii (Nantel and Gagnon, 1999). ...
Plant species with wide distributions may differ in their population dynamics across their range, especially in contrasting habitats. Most tiller recruitment of perennial grasses occurs vegetatively from the belowground bud bank rather than from seed. Seed reproduction often occurs under a narrower range of environmental conditions than vegetative reproduction. As a result flowering and seedling recruitment patterns of a species often differ between contrasting habitats and across its range. How vegetative reproduction and bud bank dynamics of a species vary between contrasting habitats has not been well studied and could explain the differences in its persistence and productivity between habitats. Therefore, the vegetative reproduction and dynamics of Andropogon gerardii, a dominant C4 perennial grass of the Great Plains of North America, were compared between tallgrass and northern mixedgrass prairie habitats. Bud production and tiller recruitment in 10 populations were examined throughout an annual growing cycle in the northern mixedgrass prairie of South Dakota. Bud bank characteristics, and individual and population performance were compared with previous work conducted in Kansas tallgrass prairie. Stage-structured matrix models examined population growth rates. Andropogon gerardii tillers produced lower numbers of buds and had lower flowering rates in mixedgrass prairie populations. The annual phenology of bud and tiller development was also contracted to fit within the shorter growing season in northern mixedgrass prairie. However, bud longevity and bud bank age structure were similar between habitats, both having buds that lived for > 2 y and multi-aged bud banks. Similar population growth rates occurred in both habitats despite lower individual performance of both flowering and vegetative reproductive capacity (i.e., bud production) in mixedgrass prairie populations. Lower regional productivity of A. gerardii in northern mixedgrass prairie than in tallgrass prairie does not appear to be due to differences in bud and tiller population growth. Instead, sparse or patchy suitable habitat and/or reduction in tiller size may explain its reduced productivity. Lower population growth rates may be observed in other habitats or in years with harsher environmental conditions that further lower individual performance.
... One reason may be that high abundance in the center may incur strong density dependence, causing a decrease in survival or reproduction in center populations and resulting in similar performance estimates across the range. Alternatively, temporal variation in population performance may be more important than mean performance (Angert 2009, Gerst et al. 2011; thus, discrepancies in performance between the center and edge may only be noticeable in poor years (Nantel and Gagnon 1999). Therefore, Manuscript Additionally, it is unclear whether the ACM is applicable to endemic species that occupy narrow ranges that generally do not vary substantially in temperature or precipitation. ...
Species' range limits can be caused by environmental gradients, and in such cases, abundance is thought to be highest in the center of a species range and decline towards the edge (the abundant-center model). Although in theory decreased abundance is caused by a decline in performance at the edge, it has been shown that performance and abundance are not necessarily related. Few studies have compared abundance and performance in center and edge populations of endemic species, whose ranges may be restricted by the availability of specialized habitat rather than environmental gradients across their range. Additionally, range-wide studies that examine both northern and southern edge populations are rare. We used Roan Mountain rattlesnake-root (Prenanthes roanensis), a perennial plant endemic to the Southern Appalachians (USA), to compare abundance and performance between central populations and populations at the northern and southern edges of the range. To account for multiple fitness components across the life cycle, we measured performance of edge populations as vital-rate contributions to population growth rate compared to the center. Abundance did not decline at the range edge, but some vital-rate contributions were lower in edge populations compared to central populations. However, each edge population differed in which vital-rate contributions were lower compared to the center. Our results do not support the abundant-center model, and it appears that local factors are important in structuring the range of this endemic species. It is important to recognize that when implementing conservation or management plans, populations in close proximity may have substantial variation in demographic rates due to differences in the local environment.
... Understanding range limits requires comparing the vital rates of both central and peripheral populations, but until recently, this has only rarely been done (Gaston 2009), and the majority of these studies have been short in duration. For example, Nantel and Gagnon (1999) measured vital rates for central and peripheral populations of Helianthus divaricatus L. and Rhus aromatica Aiton for 3 years. Their results suggested that peripheral populations had more variability but not greater mortality. ...
Populations at the periphery of a species range are thought to be less viable than those in the center because they are at the limit of their ecological tolerances. Plant population viability is determined primarily by mortality and recruitment, thus knowing differences in vital rates between central and peripheral populations is key to understanding range limits. Silene spaldingii S. Watson is a long-lived iteroparous plant that occurs throughout the eastern Columbia Plateau region of eastern Washington and adjacent Idaho and Oregon and is disjunct in northwest Montana. I recorded the fate of mapped S. spaldingii plants annually for 10 years in four populations, two from eastern Washington and two from Montana. Recruitment averaged three times higher and relatively constant at two central populations in Washington compared with two peripheral sites in Montana. Mortality was three times higher at one of the central populations compared with the remaining three sites due to vole predation. Vole activity was observed at the second central population but came too late in the study to be certain that it resulted in mortality. Vole predation was not observed in the peripheral populations. My results suggest that peripheral populations of S. spaldingii may only be able to persist as long as predation or other sources of mortality remain low and that intrinsic low and variable recruitment rates coupled with predation may help define the eastern range margin of this species.
