Alpine Species Distribution in the Karakoram Mountain Range
An exploration of species range shifts in the Himalayas.
There are multiple ways that species respond to climatic changes, which can be seen either through phenotypic plasticity, evolutionary adaptations, or by shifting their ecological ranges. Range shifts are important for species to shift to a more optimal habitat as conditions in their original habitat changes, likely through temperature increases. However, it could also subject species to new niches they are maladapted to, or for mountainous alpine species that already exist at the upper altitudinal limit of the mountain, there is no new habitats for these species to migrate to, and would result to range contractions (He et al., 2019). Furthermore, the velocity of change is often not matched by species responses due migration lag, which is the time difference between when there is a temperature increase to when a species successfully colonizes a new elevation (Dullinger et al., 2012). These compounding issues are of particular threat to the Himalayan regions, which is predicted to be warming faster than the global average (Kumar et al. 2006). This exploratory investigation will aim to visualize species response and distribution on sites within the Karakoram mountain range in Pakistan.
Floral abundance and distribution in the high alpine is a dynamic field of study in the face of contemporary climate change. In regions such as the Himalayas, vegetation species are particularly vulnerable as their distributions are mainly determined by the cold climates of the subnival zones, and as a result, montane floras are often endemic (Telwala et al., 2013). The onset of rapid climate warming poses a high risk to the abundance and richness of these species if they are unable to respond to these changes.
The first European expeditions to the Karakoram mountains was accounted to be as early as 1847, but it was in 1914 when Giotto Dainelli, an Italian geographer, made his first expedition, and in 1930, he returned again for a second expedition. In these voyages, alongside other botanists and geographers, Dainelli conducted a study of the flora in the region and marked their upper limits in the northern slopes of the Karakoram. On his second expedition, he noted that several species now have extended their upper ranges by 10m to 100m. This botanical investigation is critical in providing a baseline for future studies in studying range shifts of Karakoram species.
Dr. Nina Hewitt conducted vegetation surveys in the central Karakoram in 2016 which aimed to evaluate long-term changes in distribution limits by comparing contemporary observations with Dainelli’s historical records.
Dainelli's historical database has been digitized and tabulated on Dr. Hewitt's website:
Field Methodology
Sites
Sites were set up in 5 m x 5 m plots along transects in the north facing slopes of upper Thalle Valley, upper Baumharel, and the Deosai Plateau.
Data collection
Species presence and identification was recorded. The transects extended from 3800 m to slope top, with 2 quadrants per 100m in elevation. 146 species from 83 different generas were identified.
This coordinate is located at the Deosai top site, which is an alpine plateau.
Exploring the 2016 data
These exploratory graphs visualize the distribution of species data across elevations. Generalist species are adapted to a wide range of elevations, whereas specialist species have much smaller ranges. In particular, the data is organized so that the generalists are grouped together to the right, and the specialists are grouped together to the left. You will notice that for Baumharel, there is no distinctive specialist vs generalist species as all species occupy similar elevational ranges. This is because the Baumharel site was extremely restricted in the elevational zones that vegetation could establish. The slopes also limited access for researchers.
Click the graphs to zoom in.
Click to enlarge
Short answer questions
Species presence and ranges
How to use this 3D map to investigate the data:
The height and colour of the 3D conical protrusions indicate the species abundance of the top 10 most frequently occurring species across the sites. Toggle between the different species on the right-hand drop-down 'Layers' panel to view different species. Clicking on the data points will show more information about the precise percent cover data.
Turn on the ranges layers to compare the range shift between the historical Dainelli observations (dark blue) and the 2016 study (red). The species without corresponding range limits mean that they were not recorded in the historical Dainelli dataset, and therefore there are no range comparisons available. Rendering the range lines may take processing time.
Using the 'Custom Plane' dropdown menu, lower the opacity to 0.5 and move the altitude to around 4300 to create a maneuverable plane to help visualize available species habitat in the surrounding mountains.
Recommended viewing in a separate window (click on button in top right corner).
3D visualization of alpine species abundance and ranges
Short answer questions
Statistical Analyses
R is a common programming language used by ecologists to conduct statistical analyses on their data to examine interesting patterns, test for significance, or model future predictions. A simple annotated script below guides you through calculating the Shannon-Wiener's diversity index using the 'vegan' R package. There are over 10 thousand different R packages that allow you to do many different types of analyses. The green text explains what each line of code means, and if you are interested in test running the code below with your own data, UBC Jupyter Notebooks offers a friendly interface for students to start writing their own R script.
shannons diversity
Short answer questions
Implications for the future
The Intergovernmental Panel on Climate Change (IPCC) has established that high alpine zones and arctic biomes are warming at a faster rate than the global average (IPCC, 2013). Species composition and resilience has greatly changed in recent decades and are particularly vulnerable to the effects of climate change. Freeman et al. (2018) published a landmark article that described a phenomenon they titled an "escalator to extinction", in which species that live in the high alpine will eventually be driven to local extirpation as climate change causes ranges to shift upward. While their study was conducted on tropical montane ecosystems for bird species, their findings can be applied around the world. Research on vegetation shifts in the Himalayas echoes the results (Dolezal et al. 2016). Dolezal et al. (2016) also tested a thermophilization hypothesis, a process that predicts an increased abundance of species more adapted to warmer temperatures. This will further increase competition for specialist, subnival species, and this can be seen in this Karakoram data.
While this preliminary exploration of the data does not include analysis for statistical significance of range shifts and changes from a historical baseline, it provides important insight into the trend of species in the eastern Himalayas. Future studies in this region can examine the change of composition between generalists and specialists to identify beneficial physiological adaptations for survival, or if data collection continues to provide consistent monitoring, a better understanding of species on this "escalator to extinction" can be better identified for conservation.
Citations
Dolezal, J., Dvorsky, M., Kopecky, M., Liancourt, P., Hiiesalu, I., Macek, M., . . . Schweingruber, F. (2016). Vegetation dynamics at the upper elevational limit of vascular plants in Himalaya. Scientific Reports 6(1). doi:10.1038/srep24881
Freeman, B. G., Scholer, M. N., Ruiz-Gutierrez, V., & Fitzpatrick, J. W. (2018). Climate change causes upslope shifts and mountaintop extirpations in a tropical bird community. Proceedings of the National Academy of Sciences, 115(47), 11982-11987. doi:10.1073/pnas.1804224115
IPCC 2013, Climate Change 2013: The Physical Science Basis Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. In: (eds. Stocker, T. F. et al.), 1535 pp.(Cambridge University Press & New York, 2013)
