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(a) Fire scar on a Jack pine and (b) porcupine feeding scar on a red pine. (Photo credit: Serge Payette, 20 May 2015.)
Source publication
Past feeding activities of the North American porcupine (Erethizon dorsatum L.) in an overmature forest were reconstructed using tree-ring dated feeding scars on jack pine (Pinus banksiana Lamb.) trees in Parc national du Bic (Quebec). Following a long fire-free period, most pines that regenerated after the 1847 fire are currently senescent, moribu...
Citations
... Several jack pine trees become senescent after 80 y (21). At age 130-150 y, most trees are dying, and the absence of fire for a period of 150-200 y generally prevents the regeneration of the species (26,43,44). Jack pine rarely reaches an age greater than 250 y, although a 351-year-old tree was still thriving about 100 km south of the species limit in northern Quebec (45). ...
The Earth's climate has been warming rapidly since the beginning of the industrial era, forcing terrestrial organisms to adapt. Migration constitutes one of the most effective processes for surviving and thriving, although the speed at which tree species migrate as a function of climate change is unknown. One way to predict latitudinal movement of trees under the climate of the twenty-first century is to examine past migration since the Last Glacial Maximum. In this study, radiocarbon-dated macrofossils were used to calculate the velocity of past migration of jack pine (Pinus banksiana) and black spruce (Picea mariana), two important fire-adapted conifers of the North American boreal forest. Jack pine migrated at a mean rate of 19 km per century (km-cent) from unglaciated sites in the central and southeastern United States to the northern limit of the species in subarctic Canada. However, the velocity increased between unglaciated and early deglaciated sites in southern Quebec and slowed from early to mid-Holocene in central and eastern Quebec. Migration was at its lowest speed in late-Holocene times, when it stopped about 3,000 y ago. Compared with jack pine, black spruce migrated at a faster mean rate of 25 km-cent from the ice border at the last interstadial (Bølling/Allerød) to the species tree limit. The modern range of both species was nearly occupied about 6,000 y ago. The factors modulating the changing velocity of jack pine migration were closely associated with the warm-dry climate of the late Pleistocene-Holocene transition and the more humid climate of the mid- and late-Holocene.
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https://www.pnas.org/doi/epdf/10.1073/pnas.2210496119
... yrs BP was particularly favorable for fire propagation. In fact, the absence of fire for 150 to 200 years generally prevents the regeneration of jack pine (Heinselman, 1973;Desponts and Payette, 1992;Rivet et al., 2017), which would explain why it failed to maintain a presence on these sites. ...
The dynamics of the boreal forest has followed several successional trajectories during the Holocene caused by recurrent stand-scale, abiotic and biotic disturbances. Under stable environmental conditions, site disturbances should favor the regeneration of forest communities enabling the recovery process to produce forests similar to the pre-disturbance states. However, a failure in the post-disturbance recovery process can also occur to shift the forest communities to alternative states. Although fire is the main disturbance factor affecting the dynamics of the boreal forest, long-term resilience of most forest ecosystems remains poorly known because of lack of stand-scale paleoecological evidence. To evaluate the resilience ability of boreal forest ecosystems, we reconstructed their Holocene fire history and documented their successional pathways at the stand scale in two climatically-contrasted regions (western continental versus eastern humid climates of boreal Québec, Canada) based on botanically-identified and ¹⁴C-dated soil charcoal remains. Since mid-Holocene, western closed-crown conifer forests were resilient to fire disturbance, but hardwood trees declined significantly. Yet in the eastern region, closed-crown conifer forests similar to that observed today seems to have remained in place since its origin. In both regions, moderate fire frequency leads to a recurrence dynamics that favors renewal of forests stands with the same composition. However, balsam fir – paper birch stands follow a successional pattern characterized by the establishment of paper birch, with subsequent increasing abundance of balsam fir. This allows the maintenance of forests composed of these species, whose dominance fluctuates according to the time elapsed since the last fire. The succession from black spruce to balsam fir stands seems to be an uncommon process that requires a prolonged fire-free period. Although most closed-crown forests are resilient postfire ecosystems which have persisted over several millennia, their resilience is precarious as evidenced by the transformation of some forests into lichen woodlands after fire.
... In general, jack pine becomes senescent after 80 years (Rudolph and Laidly 1990). At age 130-150 years, most trees are dying, and the absence of fire for a period of 150-200 years generally prevents the regeneration of jack pine (Heinselman 1973;Desponts and Payette 1992;Le Goff and Sirois 2004;Rivet et al. 2017), although jack pine exhibits semi-serotiny and a lack of it in some populations. ...
... Shift from black spruce-to jack pine-dominated communities in the James Bay area is also occurring in most sites burned over the last decades (Lavoie and Sirois 1998). Isolated jack pine communities in the northern hardwood and the boreal zones of Quebec (Blouin 1970;Pellerin and Lavoie 2003;Rivet et al. 2017) are thus maintained as disjunct populations similar to the PGJ situation. Seed and leaf macrofossils of jack pine distributed at different intervals in peat deposits of a Sphagnum bog east of Quebec City (Pellerin and Lavoie 2003) is testimony to the long-term persistence of the species over the last 9000 years. ...
Plant species are unique in their biological traits and biogeographical history resulting in distinctive species distributions. Continuous and fragmented ranges of varying size and shape have captured the interest of biogeographers. Fragmented distribution into isolated populations is a common pattern of temperate and boreal species caused by contraction and expansion processes. Jack pine ( Pinus banksiana ), a North-American tree species, is among a multitude of species showing range distributions fragmented to isolated populations. Whether disjunct jack pine forests are remnants of larger Holocene populations or newly established populations due to long-distance transport remains unanswered. We used a retrospective approach based on soil macrocharcoal analysis to address the question of residency of a disjunct population in the boreal forest. The studied forest forms a disjunct population of a former regional population that has contracted since the mid-Holocene. Short to moderately long fire inter...
During the twentieth century, the North American porcupine (Erethizon dorsatum) was common in the Black Hills of western South Dakota and northeastern Wyoming. However, the low number of recent observations in the region has led to concern that porcupine populations have declined. We conducted systematic surveys to assess porcupine occurrence at two hundred and sixty-three 1-ha sites in the Black Hills National Forest, Custer State Park, Jewel Cave National Monument, Mount Rushmore National Memorial, and Wind Cave National Park during 2016–2017. We observed no porcupines or recent feeding sign. We also noted few recent observations in information compiled from online databases and from other natural resource surveys with which we have been involved in the South Dakota Black Hills. Given the apparent abundance of porcupines in this area in the twentieth century, our results suggest that populations have declined dramatically. Predation by mountain lions (Puma concolor), habitat loss, and human-caused mortality are potential contributing factors, but estimating the degree of population declines and assessing hypotheses about the causes are hindered by a lack of long-term data on the region's porcupine populations. Moreover, accounts of the region's mammalian fauna suggest that porcupines were not abundant in the region during the late 1800s but became common in the early twentieth century.
The distribution of vegetation zones in northeastern North America forms a gradual transition from closed to open forests, and to tundra. Closed forests near the open forest/tundra boundary generally correspond to residual patches of a once larger forest community. Whether these forest patches have survived as untouched, fire-free communities or as resilient communities during the Holocene remains unknown. To answer to this question, we reconstructed the successional history of two black spruce closed-crown forests and one jack pine forest near the northern limit of closed forest ecosystems. Stand-scale postfire succession was analysed based on charcoal macrofossils. Extensive ¹⁴ C dating and botanical identification of charcoal fragments located at the organic soil surface and buried in the mineral podzolic solum were used to reconstruct the successional pathways of the sites. The forest sites developed in a context of continuous fire disturbance, except for a short interval of several centuries. The fire history of the three sites is similar with a fire frequency of 34–37 fires over the last 5000–5800 years, which corresponds to a mean fire interval of 150–180 years. Based on parametric and non-parametric estimators, the regional fire regime of the Laforge area (combined fire data of two sites located about 7 km from each other) was most likely characterized by 38 fires over the last 5000–5800 years, i.e., at an interval of about 150–160 years. Birch (Betula papyrifera) was present in the spruce sites between 5800 and 3000 cal. years BP. Jack pine arrived at the pine site about 3000 cal. years BP, at the time when birch was extirpated from the spruce forests. The closed-crown forests near the open forest/tundra boundary are resilient postfire ecosystems which regenerated successfully since mid-Holocene. Compositional change of these forests, which led to the decline of birch but maintained the dominance of conifers, appears related to cooler and wetter conditions of late Holocene. Climatic conditions also slowed the eastward migration of jack pine, which explains the late arrival of this species at its northeastern range. Our data suggest that fire disturbance in these sites of the boreal biome has been a continuous and positive regenerative process since mid-Holocene despite the influence of climatic change on the tree flora.
