The Railway's Botanical Tapestry

 

The Railway's Botanical Tapestry: Exploring Plant Communities Along the Tracks

Jianyu Guo, Xingjian Yang, Tanner Alger – BIO 368, Grinnell College

 

Imagine that you are living in a “peaceful” village, a giant snake shouting and running by you every day for several times. The wind is blowing, and people are shaking. Sometimes, some tiny monsters will challenge the gigantic snake, but left over is their bone and blood. People discuss secretly in what way they can leave this horrible place, but they know they are like prisoners and can never ever escape here. People are forgotten; they are not caught by someone, and through to this place, this is the place they are choosing, no one is forcing them.

 

This is the situation that plants live in the railway met. The living conditions obviously are not more ideal than living in a forest or a prairie, but why plants and what plants choose to live here? What factors affect those plants under such conditions? Most importantly, what can we learn from the railway vegetation embankment? These questions are discussed in the article (Juha Suominen, 1969)

 

Railways offer attractive grounds to study plant communities. This is mainly due to their homogenized construction (their height, materials used, disturbance frequencies, water economies, and soil compositions). Still, they often cover large expanses of area and traverse through various climates and ecotypes. As we know from general knowledge and observation, varied environmental conditions lead to differences in plant species and the composition and density of those species within an area. In 1969, Juha Suominen, a researcher from Finland, saw railways as an ample place to study how plant communities grow on similar environmental structures (the railway) and how the communities and their percent cover may vary across microclimates and different forms of environmental exposure. They note that studying how factors such as slopes, soil and soil chemical types, seepages, and human interference are essential for understanding plant communities and their species density. However, doing so in natural environments creates a very intricate complex that is difficult to distinguish individual effects. However, the construction of a railway controls these factors and does so across an extensive array of environments. The author conducted their study and wrote their paper, to fill this gap in research about the conditions and exposures in an environment shape the plant ecology, using railways as the means of execution.

Figure 1, the landscape of the railway

What could cause the difference in plant species?

1. N slope and S slope
2. high and low barrier
3. upper and lower parts of high embankment
4. the surrounding
5. disturbed railway embankments
6. new or old embankments

With these variations in the railway landscape, the plant species exhibit significant differences, leading to the identification of three distinct vegetation units within this triangle. These units highlight the following preferences:

1. Xerothermic vegetation (a): This type thrives on the southern slope and high embankments, giving rise to extensive grasslands.

2. Health forest-type vegetation (b): Preferring the northern slope, this vegetation unit is surrounded by coniferous boreal forests.

3. Rather mesic grassland vegetation (c): Found predominantly on the low embankments and northern slopes, cultivated areas and meadows typically surround this vegetation unit.

Figure 2, the factor influencing the embarkment of vegetation around railway

In a similar light, the Grinnell College campus has a railway running longitudinally throughout its whole length. We aimed to analyze the presence of different plant species at varying distances from the railway. We measured gradients along the railway with a total distance of 2 meters, using quarter-meter quadrats to space and outline the study area. Each study site was spaced 50 meters from one another and were alternated from the east side to the west side of the railway each time.

 

reference

Suominen, J. (1969). The plant cover of Finnish railway embankments and the ecology of their species. Annales Botanici Fennici, 6(3), 183–235. http://www.jstor.org/stable/23724224