Evolutionary Diversity Peaks at Mid-Elevations Along an Amazon-to-Andes Elevation Gradient

Elevation gradients present enigmatic diversity patterns, with trends often dependent on the dimension of diversity considered. However, focus is often on patterns of taxonomic diversity and interactions between diversity gradients and evolutionary factors, such as lineage age, are poorly understood. We combine forest census data with a genus level phylogeny representing tree ferns, gymnosperms, angiosperms, and an evolutionary depth of 382 million years, to investigate taxonomic and evolutionary diversity patterns across a long tropical montane forest elevation gradient on the Amazonian flank of the Peruvian Andes. We find that evolutionary diversity peaks at mid-elevations and contrasts with taxonomic richness, which is invariant from low to mid-elevation, but then decreases with elevation. We suggest that this trend interacts with variation in the evolutionary ages of lineages across elevation, with contrasting distribution trends between younger and older lineages. For example, while 53% of young lineages (originated by 10 million years ago) occur only below ∼1,750 m asl, just 13% of old lineages (originated by 110 million years ago) are restricted to below ∼1,750 m asl. Overall our results support an Environmental Crossroads hypothesis, whereby a mid-gradient mingling of distinct floras creates an evolutionary diversity in mid-elevation Andean forests that rivals that of the Amazonian lowlands.

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Evolutionary heritage shapes tree distributions along an Amazon-to-Andes elevation gradient

10.1101/2020.06.11.143875 ◽

2020 ◽

Author(s):

Andy R. Griffiths ◽

Miles R. Silman ◽

William Farfán Rios ◽

Kenneth J. Feeley ◽

Karina García Cabrera ◽

...

Keyword(s):

Census Data ◽

Environmental Changes ◽

Elevation Gradient ◽

Cloud Base ◽

Valuable Insight ◽

Montane Forests ◽

Peruvian Andes ◽

Habitat Specialisation ◽

Tropical Montane Forests ◽

Highly Sensitive

ABSTRACTUnderstanding how evolutionary constraints shape the elevational distributions of tree lineages provides valuable insight into the future of tropical montane forests under global change. With narrow elevational ranges, high taxonomic turnover, frequent habitat specialisation, and exceptional levels of endemism, tropical montane forests and trees are predicted to be highly sensitive to environmental change. Using plot census data from a gradient traversing >3000 m in elevation on the Amazonian flank of the Peruvian Andes, we employ phylogenetic approaches to assess the influence of evolutionary heritage on distribution trends of trees at the genus level. We find that closely related lineages tend to occur at similar mean elevations, with sister genera pairs occurring a mean 254 m in elevation closer to each other than the mean elevational difference for all genera pairs. We also demonstrate phylogenetic clustering both above and below 1750 m a.s.l, corresponding roughly to the cloud-base ecotone. Belying these general trends, some lineages occur across many different elevations. However, these highly plastic lineages are not phylogenetically clustered. Overall, our findings suggest that tropical montane forests are home to unique tree lineage diversity, constrained by their evolutionary heritage and vulnerable to substantial losses under environmental changes, such as rising temperatures or an upward shift of the cloud base.

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Landscape-scale changes in forest structure and functional traits along an Andes-to-Amazon elevation gradient

Biogeosciences Discussions ◽

10.5194/bgd-10-15415-2013 ◽

2013 ◽

Vol 10 (9) ◽

pp. 15415-15454 ◽

Cited By ~ 6

Author(s):

G. P. Asner ◽

C. Anderson ◽

R. E. Martin ◽

D. E. Knapp ◽

R. Tupayachi ◽

...

Keyword(s):

Functional Traits ◽

Forest Structure ◽

Structural Information ◽

Plant Cover ◽

Elevation Gradient ◽

Imaging Spectroscopy ◽

Landscape Scale ◽

Elevation Gradients ◽

Peruvian Andes ◽

Environmental Controls

Abstract. Elevation gradients provide opportunities to explore environmental controls on forest structure and functioning, but plot-based studies have proven highly variable due to limited geographic scope. We used airborne imaging spectroscopy and LiDAR (light detection and ranging) to quantify changes in three-dimensional forest structure and canopy functional traits in a series of 25 ha landscapes distributed along a 3300 m elevation gradient from lowland Amazonia to treeline in the Peruvian Andes. Canopy greenness, photosynthetic fractional cover and exposed non-photosynthetic vegetation varied as much across lowland forests (100–200 m) as they did from the lowlands to the Andean treeline (3400 m). Elevation was positively correlated with canopy gap density and understory vegetation cover, and negatively related to canopy height and vertical profile. Increases in gap density were tightly linked to increases in understory plant cover, and larger gaps (20–200 m2 produced 25–30 times the response in understory cover than did smaller gaps (< 5 m2. Scaling of gap size to gap frequency was, however, relatively constant along the elevation gradient, which when combined with other canopy structural information, indicates equilibrium turnover patterns from the lowlands to treeline. Our results provide a first landscape-scale quantification of forest structure and canopy functional traits with changing elevation, thereby improving our understanding of disturbance, demography and ecosystem processes in the Andes-to-Amazon corridor.

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Species richness and β-diversity patterns of macrolichens along elevation gradients across the Himalayan Arc

Scientific Reports ◽

10.1038/s41598-021-99675-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Subzar Ahmad Nanda ◽

Manzoor-ul Haq ◽

S. P. Singh ◽

Zafar A. Reshi ◽

Ranbeer S. Rawal ◽

...

Keyword(s):

Species Richness ◽

Species Turnover ◽

Elevation Gradient ◽

Conservation Strategies ◽

Elevational Gradients ◽

Elevation Gradients ◽

Diversity Patterns ◽

Β Diversity ◽

Shaped Pattern ◽

The Himalaya

AbstractUnderstanding the species richness and β-diversity patterns along elevation gradients can aid in formulating effective conservation strategies particularly in areas where local anthropogenic stresses and climate change are quite significant as in the Himalaya. Thus, we studied macrolichen richness and β-diversity along elevational gradients at three sites, namely Kashmir (2200 to 3800 m a.m.s.l), Uttarakhand (2000–3700 m a.m.s.l) and Sikkim (1700 to 4000 m a.m.s.l) which cover much of the Indian Himalayan Arc. In all, 245 macrolichen species belonging to 77 genera and 26 families were collected from the three sites. Only 11 species, 20 genera and 11 families were common among the three transects. Despite the differences in species composition, the dominant functional groups in the three sites were the same: foliose, fruticose and corticolous forms. The hump-shaped elevation pattern in species richness was exhibited by most of the lichen groups, though an inverse hump-shaped pattern was also observed in certain cases. β-diversity (βsor) based on all pairs of comparisons along an elevation gradient varied from 0.48 to 0.58 in Kashmir, 0.03 to 0.63 in Uttarakhand and 0.46 to 0.77 in Sikkim. The contribution of turnover to β-diversity was more than nestedness at all the three transects. Along elevation β-diversity and its components of turnover and nestedness varied significantly with elevation. While species turnover increased significantly along the elevation in all the three transects, nestedness decreased significantly in Kashmir and Sikkim transects but increased significantly in the Uttarakhand transect. Except for the Kashmir Himalayan elevation transect, stepwise β-diversity and its components of turnover and nestedness did not vary significantly with elevation. The present study, the first of its kind in the Himalayan region, clearly brings out that macrolichen species richness, β-diversity, and its components of turnover and nestedness vary along the elevation gradients across the Himalayan Arc. It also highlights that contribution of turnover to β-diversity is higher in comparison to nestedness at all the three transects. The variations in species richness and diversity along elevation gradients underpin the importance of considering elevational gradients in planning conservation strategies.

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Landscape-scale changes in forest structure and functional traits along an Andes-to-Amazon elevation gradient

Biogeosciences ◽

10.5194/bg-11-843-2014 ◽

2014 ◽

Vol 11 (3) ◽

pp. 843-856 ◽

Cited By ~ 64

Author(s):

G. P. Asner ◽

C. B. Anderson ◽

R. E. Martin ◽

D. E. Knapp ◽

R. Tupayachi ◽

...

Keyword(s):

Functional Traits ◽

Forest Structure ◽

Plant Cover ◽

Elevation Gradient ◽

Landscape Scale ◽

Canopy Gap ◽

Turnover Rates ◽

Elevation Gradients ◽

Peruvian Andes ◽

Environmental Controls

Abstract. Elevation gradients provide opportunities to explore environmental controls on forest structure and functioning. We used airborne imaging spectroscopy and lidar (light detection and ranging) to quantify changes in three-dimensional forest structure and canopy functional traits in twenty 25 ha landscapes distributed along a 3300 m elevation gradient from lowland Amazonia to treeline in the Peruvian Andes. Elevation was positively correlated with lidar-estimated canopy gap density and understory vegetation cover, and negatively related to canopy height and the vertical partitioning of vegetation in canopies. Increases in canopy gap density were tightly linked to increases in understory plant cover, and larger gaps (20–200 m2) produced 25–30 times the response in understory cover than did smaller gaps (< 5 m2). Vegetation NDVI and photosynthetic fractional cover decreased, while exposed non-photosynthetic vegetation and bare soil increased, with elevation. Scaling of gap size to gap frequency (λ) was, however, nearly constant along the elevation gradient. When combined with other canopy structural and functional trait information, this suggests near-constant canopy turnover rates from the lowlands to treeline, which occurs independent of decreasing biomass or productivity with increasing elevation. Our results provide the first landscape-scale quantification of forest structure and canopy functional traits with changing elevation, thereby improving our understanding of disturbance, demography and ecosystem processes in the Andes-to-Amazon corridor.

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Taxonomic diversity gradients through geological time

Diversity and Distributions ◽

10.1046/j.1472-4642.2001.00106.x ◽

2001 ◽

Vol 7 (4) ◽

pp. 175 ◽

Cited By ~ 1

Author(s):

J. Alistair Crame

Keyword(s):

Taxonomic Diversity ◽

Geological Time ◽

Diversity Gradients

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Multi-Year NDVI Values as Indicator of the Relationship between Spatiotemporal Vegetation Dynamics and Environmental Factors in the Qaidam Basin, China

Remote Sensing ◽

10.3390/rs13071240 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1240

Author(s):

Junpeng Lou ◽

Guoyin Xu ◽

Zhongjing Wang ◽

Zhigang Yang ◽

Sanchuan Ni

Keyword(s):

Environmental Factors ◽

Vegetation Dynamics ◽

Vegetation Index ◽

Qaidam Basin ◽

Elevation Gradient ◽

Practical Significance ◽

Elevation Gradients ◽

Relative Contribution ◽

Significant Difference ◽

Different Altitudes

The Qaidam Basin is a unique and complex ecosystem, wherein elevation gradients lead to high spatial heterogeneity in vegetation dynamics and responses to environmental factors. Based on the remote sensing data of Moderate Resolution Imaging Spectroradiometer (MODIS), Tropical Rainfall Measuring Mission (TRMM) and Global Land Data Assimilation System (GLDAS), we analyzed the spatiotemporal variations of vegetation dynamics and responses to precipitation, accumulative temperature (AT) and soil moisture (SM) in the Qaidam Basin from 2001 to 2016. Moreover, the contribution of those factors to vegetation dynamics at different altitudes was analyzed via an artificial neural network (ANN) model. The results indicated that the Normalized Difference Vegetation Index (NDVI) values in the growing season showed an overall upward trend, with an increased rate of 0.001/year. The values of NDVI in low-altitude areas were higher than that in high-altitude areas, and the peak values of NDVI appeared along the elevation gradient at 4400–4600 m. Thanks to the use of ANN, we were able to detect the relative contribution of various environmental factors; the relative contribution rate of AT to the NDVI dynamic was the most significant (35.17%) in the low-elevation region (< 2900 m). In the mid-elevation area (2900–3900 m), precipitation contributed 44.76% of the NDVI dynamics. When the altitude was higher than 3900 m, the relative contribution rates of AT (39.50%) and SM (38.53%) had no significant difference but were significantly higher than that of precipitation (21.97%). The results highlight that the different environmental factors have various contributions to vegetation dynamics at different altitudes, which has important theoretical and practical significance for regulating ecological processes.

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Expected impacts of climate change on tree ferns distribution and diversity patterns in subtropical Atlantic Forest

Perspectives in Ecology and Conservation ◽

10.1016/j.pecon.2021.03.007 ◽

2021 ◽

Author(s):

André Luís de Gasper ◽

Guilherme Salgado Grittz ◽

Carlos Henrique Russi ◽

Carlos Eduardo Schwartz ◽

Arthur Vinicius Rodrigues

Keyword(s):

Climate Change ◽

Atlantic Forest ◽

Diversity Patterns ◽

Tree Ferns ◽

Impacts Of Climate Change

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Ant diversity patterns across tropical elevation gradients: effects of sampling method and subcommunity

Ecosphere ◽

10.1002/ecs2.2798 ◽

2019 ◽

Vol 10 (8) ◽

Cited By ~ 3

Author(s):

John T. Longino ◽

Michael G. Branstetter ◽

Philip S. Ward

Keyword(s):

Sampling Method ◽

Elevation Gradients ◽

Diversity Patterns ◽

Ant Diversity

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Elevation Gradient Altered Soil C, N, and P Stoichiometry of Pinus taiwanensis Forest on Daiyun Mountain

Forests ◽

10.3390/f10121089 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1089

Author(s):

Lan Jiang ◽

Zhongsheng He ◽

Jinfu Liu ◽

Cong Xing ◽

Xinguang Gu ◽

...

Keyword(s):

Elevation Gradient ◽

C:N Ratio ◽

Phosphate Fertilizer ◽

High Elevation ◽

Driving Factors ◽

Slope Position ◽

Elevation Gradients ◽

Soil C ◽

Soil P ◽

C And N

Researches focused on soil carbon (C), nitrogen (N), and phosphorus (P) content and the stoichiometry characteristics along elevation gradients are important for effective management of forest ecosystems. Taking the soil of different elevations from 900 to 1700 m on Daiyun Mountain as the object, the elevation distribution of total C, N, and P in soil and their stoichiometry characteristics were studied. Also, the driving factors resulting in the spatial heterogeneity of soil stoichiometry are presented. The results show the following: (1) The average soil C and N content was 53.03 g·kg−1 and 3.82 g·kg−1, respectively. The content of C and N at high elevation was higher than that of at low elevation. Soil phosphorus fluctuated with elevation. (2) With increasing elevation, soil C:N ratio increased initially to 17.40 at elevation between 900–1000 m, and then decreased to 12.02 at elevation 1600 m. The changing trends of C:P and N:P were similar, and they all fluctuated with elevation. (3) Elevation, soil bulk density, and soil temperature were the main factors influencing the variation of soil C, N, and C:N. Soil pH and slope position were the driving factors for soil P, C:P, and N:P. The soil is rich in C and N, and has less total phosphorus on Daiyun Mountain. Raising the level of phosphate fertilizer appropriately can help to improve soil fertility and promote plant growth as well. In light of this information, in the near future, it will be necessary to conduct separation management of C, N, and P with regular monitoring systems to maintain favorable conditions for soil.

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