Biotic disturbance facilitates range shift at the trailing but not the leading edge of lodgepole pine's altitudinal distribution

Organisms modify their geographical distributions in response to changes in environmental conditions, or modify their affinity to such conditions, to avoid extinction. This study explored the altitudinal shift of Abies pinsapo Boiss. in the Baetic System. We analysed the potential distribution of the realised and reproductive niches of A. pinsapo populations in the Ronda Mountains (Southern Spain) by using species distribution models (SDMs) for two life stages within the current populations. Then, we calculated the species’ potential altitudinal shifts and identified the areas in which the processes of persistence and migration predominated. The realised and reproductive niches of A. pinsapo are different to one another, which may indicate a displacement in its altitudinal distribution owing to changes in the climatic conditions of the Ronda Mountains. The most unfavourable conditions for the species indicate a trailing edge (~110 m) at the lower limit of its distribution and a leading edge (~55 m) at the upper limit. Even though the differences in the altitudinal shifts between the trailing and leading edges will not cause the populations to become extinct in the short term, they may threaten their viability if the conditions that are producing the contraction at the lower limit persist in the long term.

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Humboldt’sTableau Physiquerevisited

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1904585116 ◽

2019 ◽

Vol 116 (26) ◽

pp. 12889-12894 ◽

Cited By ~ 10

Author(s):

Pierre Moret ◽

Priscilla Muriel ◽

Ricardo Jaramillo ◽

Olivier Dangles

Keyword(s):

Environmental Changes ◽

Original Data ◽

Range Shift ◽

Tree Line ◽

Tropical Andes ◽

Altitudinal Distribution ◽

Climate Change Effects ◽

Altitudinal Shift ◽

History Of ◽

Vegetation Belt

Alexander von Humboldt’sTableau Physique(1807) has been one of the most influential diagrams in the history of environmental sciences. In particular, detailed observations of the altitudinal distribution of plant species in the equatorial Andes, depicted on a cross-section of Mt. Chimborazo, allowed Humboldt to establish the concept of vegetation belt, thereby laying the foundations of biogeography. Surprisingly, Humboldt’s original data have never been critically revisited, probably due to the difficulty of gathering and interpreting dispersed archives. By unearthing and analyzing overlooked historical documents, we show that the top section of theTableau Physique, above the tree line, is an intuitive construct based on unverified and therefore partly false field data that Humboldt constantly tried to revise in subsequent publications. This finding has implications for the documentation of climate change effects in the tropical Andes. We found that Humboldt’s primary plant data above tree line were mostly collected on Mt. Antisana, not Chimborazo, which allows a comparison with current records. Our resurvey at Mt. Antisana revealed a 215- to 266-m altitudinal shift over 215 y. This estimate is about twice lower than previous estimates for the region but is consistent with the 10- to 12-m/decade upslope range shift observed worldwide. Our results show the cautious approach needed to interpret historical data and to use them as a resource for documenting environmental changes. They also profoundly renew our understanding of Humboldt’s scientific thinking, methods, and modern relevance.

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High-elevational occurrence of two tick species, Ixodes ricinus and I. trianguliceps, at their northern distributional limit

10.21203/rs.3.rs-75601/v1 ◽

2020 ◽

Author(s):

Nicolas De Pelsmaeker ◽

Lars Korslund ◽

Øyvind Steifetten

Keyword(s):

Ixodes Ricinus ◽

Tick Species ◽

Range Shift ◽

Limiting Factors ◽

Seasonal Effects ◽

Myodes Glareolus ◽

Range Limit ◽

Altitudinal Distribution ◽

Bank Voles ◽

Distributional Limit

Abstract Background: During the last decades a northward and upward range shift has been observed among many organisms across different taxa. In the northern hemisphere, ticks have been observed to have increased their latitudinal and altitudinal range limit. However, the elevational expansion at its northern distribution limit remains largely unstudied. In this study we investigated the altitudinal distribution of the exophilic Ixodes ricinus and endophilic I. trianguliceps on two mountain slopes in Norway by assessing larval infestation rates on bank voles (Myodes glareolus).Methods: During 2017 and 2018, 1325 bank voles were captured during spring, summer and autumn at 10 trapping stations ranging from 100 m to 1000 m.a.s.l in two study areas in southern Norway. We used generalized logistic regression models to estimate the prevalence of infestation of both tick species along altitude, considering study area, collection year and season, temperature, humidity and altitude interactions as extrinsic variables; and host body mass and sex as intrinsic predictor variables.Results: We found that both I. ricinus and I. trianguliceps infested bank voles at altitudes up to 1000 m.a.s.l., which is a substantial increase in altitude compared to previous findings for I. ricinus in this region. The infestation rates declined more rapidly for I. ricinus compared to I. trianguliceps, indicating that the endophilic ecology of I. trianguliceps may provide shelter from limiting factors tied to altitude. Seasonal effects limited the occurrence of I. ricinus during autumn, but I. trianguliceps was found to infest rodents at all altitudes during all seasons of both years.Conclusions: This study provides new insights into the altitudinal distribution of two tick species at their northern distributional limit, one with the potential to transmit zoonotic pathogens to both humans and livestock. With warming temperatures predicted to increase, and especially so in the northern regions, the risk of tick-borne infections is likely to become a concern at increasingly higher altitudes in the future.

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High-elevational occurrence of two tick species, Ixodes ricinus and I. trianguliceps, at their northern distribution range

Parasites & Vectors ◽

10.1186/s13071-021-04604-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Nicolas De Pelsmaeker ◽

Lars Korslund ◽

Øyvind Steifetten

Keyword(s):

Ixodes Ricinus ◽

Tick Species ◽

Distribution Range ◽

Range Shift ◽

Limiting Factors ◽

Seasonal Effects ◽

Myodes Glareolus ◽

Altitudinal Distribution ◽

Bank Voles ◽

Northern Distribution

Abstract Background During the last decades a northward and upward range shift has been observed among many organisms across different taxa. In the northern hemisphere, ticks have been observed to have increased their latitudinal and altitudinal range limit. However, the elevational expansion at its northern distribution range remains largely unstudied. In this study we investigated the altitudinal distribution of the exophilic Ixodes ricinus and endophilic I. trianguliceps on two mountain slopes in Norway by assessing larval infestation rates on bank voles (Myodes glareolus). Methods During 2017 and 2018, 1325 bank voles were captured during the spring, summer and autumn at ten trapping stations ranging from 100 m to 1000 m.a.s.l. in two study areas in southern Norway. We used generalized logistic regression models to estimate the prevalence of infestation of both tick species along gradients of altitude, considering study area, collection year and season, temperature, humidity and altitude interactions as extrinsic variables, and host body mass and sex as intrinsic predictor variables. Results We found that both I. ricinus and I. trianguliceps infested bank voles at altitudes up to 1000 m.a.s.l., which is a substantial increase in altitude compared to previous findings for I. ricinus in this region. The infestation rates declined more rapidly with increasing altitude for I. ricinus compared to I. trianguliceps, indicating that the endophilic ecology of I. trianguliceps may provide shelter from limiting factors tied to altitude. Seasonal effects limited the occurrence of I. ricinus during autumn, but I. trianguliceps was found to infest rodents at all altitudes during all seasons of both years. Conclusions This study provides new insights into the altitudinal distribution of two tick species at their northern distribution range, one with the potential to transmit zoonotic pathogens to both humans and livestock. With warming temperatures predicted to increase, and especially so in the northern regions, the risk of tick-borne infections is likely to become a concern at increasingly higher altitudes in the future.

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Projected Impact of Climate Change on Habitat Suitability of a Vulnerable Endemic Vachellia negrii (Pic.-Serm.) (Fabaceae) in Ethiopia

Sustainability ◽

10.3390/su132011275 ◽

2021 ◽

Vol 13 (20) ◽

pp. 11275

Author(s):

Arayaselassie Abebe Semu ◽

Tamrat Bekele ◽

Ermias Lulekal ◽

Paloma Cariñanos ◽

Sileshi Nemomissa

Keyword(s):

Climate Change ◽

Solar Radiation ◽

Anthropogenic Impacts ◽

Leading Edge ◽

Range Shift ◽

Suitable Habitat ◽

Herbarium Specimens ◽

Climate System Model ◽

Precipitation Seasonality ◽

Bioclimatic Variables

Species tend to shift their suitable habitat both altitudinally and latitudinally under climate change. Range shift in plants brings about habitat contraction at rear edges, forcing leading edge populations to explore newly available suitable habitats. In order to detect these scenarios, modeling of the future geographical distribution of the species is widely used. Vachellia negrii (Pic.-Serm.) Kyal. & Boatwr. is endemic to Ethiopia and was assessed as vulnerable due to changes to its habitat by anthropogenic impacts. It occurs in upland wooded grassland from 2000–3100 m.a.s.l. The main objective of this study is to model the distribution of Vachellia negrii in Ethiopia by using Maxent under climate change. Nineteen bioclimatic variables were downloaded from an open source. Furthermore, topographic position index (tpi), solar radiation index (sri) and elevation were used. Two representative concentration pathways were selected (RCP 4.5 and RC P8.5) for the years 2050 and 2070 using the Community Climate System Model (CCSM 5). A correlation analysis of the bioclimatic variables has resulted in the retention of 10 bioclimatic variables for modeling. Forty-eight occurrence points were collected from herbarium specimens. The area under curve (AUC) is 0.94, indicating a high-performance level of the model. The distribution of the species is affected by elevation (26.4%), precipitation of the driest month (Bio 14, 21.7%), solar radiation (12.9%) and precipitation seasonality (Bio15, 12.2%). Whereas the RCP 8.5 has resulted in decrease of suitable areas of the species from the current 4,314,153.94 ha (3.80%) to 4,059,150.90 ha (3.58%) in 2050, this area will shrink to 3,555,828.71 ha in 2070 under the same scenario. As climate change severely affects the environment, highly suitable areas for the growth of the study subject will decrease by 758,325 ha. The study’s results shows that this vulnerable, endemic species is facing habitat contraction and requires interventions to ensure its long-term persistence.

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High-elevational occurrence of two tick species, Ixodes ricinus and I. trianguliceps, at their northern distribution range

10.21203/rs.3.rs-75601/v2 ◽

2021 ◽

Author(s):

Nicolas De Pelsmaeker ◽

Lars Korslund ◽

Øyvind Steifetten

Keyword(s):

Ixodes Ricinus ◽

Tick Species ◽

Distribution Range ◽

Range Shift ◽

Limiting Factors ◽

Seasonal Effects ◽

Myodes Glareolus ◽

Altitudinal Distribution ◽

Bank Voles ◽

Northern Distribution

Abstract Background: During the last decades a northward and upward range shift has been observed among many organisms across different taxa. In the northern hemisphere, ticks have been observed to have increased their latitudinal and altitudinal range limit. However, the elevational expansion at its northern distribution range remains largely unstudied. In this study we investigated the altitudinal distribution of the exophilic Ixodes ricinus and endophilic I. trianguliceps on two mountain slopes in Norway by assessing larval infestation rates on bank voles (Myodes glareolus).Methods: During 2017 and 2018, 1325 bank voles were captured during spring, summer and autumn at 10 trapping stations ranging from 100 m to 1000 m.a.s.l. in two study areas in southern Norway. We used generalized logistic regression models to estimate the prevalence of infestation of both tick species along altitude, considering study area, collection year and season, temperature, humidity and altitude interactions as extrinsic variables; and host body mass and sex as intrinsic predictor variables.Results: We found that both I. ricinus and I. trianguliceps infested bank voles at altitudes up to 1000 m.a.s.l., which is a substantial increase in altitude compared to previous findings for I. ricinus in this region. The infestation rates declined more rapidly for I. ricinus compared to I. trianguliceps, indicating that the endophilic ecology of I. trianguliceps may provide shelter from limiting factors tied to altitude. Seasonal effects limited the occurrence of I. ricinus during autumn, but I. trianguliceps was found to infest rodents at all altitudes during all seasons of both years.Conclusions: This study provides new insights into the altitudinal distribution of two tick species at their northern distributional range, one with the potential to transmit zoonotic pathogens to both humans and livestock. With warming temperatures predicted to increase, and especially so in the northern regions, the risk of tick-borne infections is likely to become a concern at increasingly higher altitudes in the future.

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