Over the past decade(!) I have worked off and on with Czech colleagues on various aspects of the coevolution of soils, landforms, and ecosystems in forests, particularly unmanaged forests of central Europe. In the course of working on one of those projects, dealing with biogeomorphological domination of hydrology, geomorphology, and vegetation in high elevations of the Sumava Mountains, we began to think, not for the first time, about different ways to tell the story. The conventional scientific article version is described, and is available, here.
I recalled meeting, and being impressed by, the work of an artist friend of my research colleague Pavel Šamonil--Petr Mores, based in Brno, Czech Republic (yes, I know, there’s a vowel shortage in Brno). Pavel connected me to Petr, and we began thinking and working on scientific storytelling through Petr’s medium, painting. I have previously blogged about these conversations: Pictures of landscape evolution, Underground art.
Now we take a deeper dive into Petr’s most complex piece, shown below. The creative process is partly described in the earlier posts, but mainly it consisted of Petr’s multiple iterations of the illustration, followed by Petr’s scientific questions for Pavel and myself, and our comments and critique on the pictures. This is just a bumper-sticker version of how the collaboration worked; Petr spent a lot of time working on and thinking about not just the whole scene, but how to best depict specific aspects such as subsurface geology, soils, living and dead trees, etc. Luckily Mr. Mores enjoys nothing more than spending time in forests, and doing his art!
Biogeomorphological Domination by Petr Mores. I assigned the name; Petr may choose to give a better one.
Let’s break it down a bit. For starters, focus on the aboveground portion. Unlike many managed forests (tree farms being the most managed type), old growth and unmanaged forests have trees of a number different ages—both living and dead. These range from seedlings to mature trees to dead trees. The latter include some dying or recently deceased, with yellowish-brown needles still attached, and standing dead, with no needles. You’ll see downed trunks, both broken and uprooted. Some are still intact; some are highly decomposed, and serving as nurse logs for the seedlings, as is common in the Norway spruce (Picea abies) that dominate the study sites. One of the advantages of Petr’s depiction is that he was able to show all of these in a single scene, whereas with photographs it would be difficult, if even possible, to photograph trees in all of these states in a single image. After much discussion, we agreed that a surface area of about 30 by 30 m was necessary to provide enough room to show all we wanted to show, but with enough local detail to achieve our goals.
Now let’s go down to the ground surface, where the painting shows a number of the key effects of the Norway spruce on topography, soils, and hydrology. Some trees produce mounds at their base as the roots grow laterally near the surface and displace soil. Norway spruce is one of these (some other trees have fewer lateral roots and have little or no surface mounding). The painting shows not only mounds at tree bases, but some older mounds from past trees—the mounds do generally persist—and cutaway views showing the root mass at the base of the tree. Fallen logs and large lateral roots near the surface can also create more linear mounded features. This helps produce a hummocky topography. Another major effect is uprooting. Not only does this displace the underlying soil and rock pulled up with the rootwad, but as the rootwad eventually decays it leaves a pit-mound pair. The pit-mound microtopography, along with the hummocky topography, profoundly influences subsequent water flows, soil formation, and ecological processes. Since the roots often encircle stony glacial and periglacial debris, or penetrate bedrock where the latter is near the surface, uprooting also “mines” rock, deepening soil and bringing rock fragments to the surface.
Another advantage of painting vis-à-vis photography is the ability to show both above- and below-ground features simultaneously. The camera cannot see beneath the surface, and photographs of soil pits, outcrops, and exposures cannot show well both the exposed subsurface material and the surrounding landscape. Petr was already quite experienced in painting natural landscapes, but not so much on the subsurface. He visited a number of quarries and outcrops, and studied many of our photographs to get a feel for the rock and soil portion.
Some key things to note: The rock is jointed and fractured, as it nearly always is. These features are important for allowing water, roots and other biota to get into the rock, accelerating rock weathering. This is generally associated with positive feedbacks, where initially less resistant areas weather first, facilitating further weathering, and more resistant portions of the rock persist. This often—as in our study area—creates a spatially variable pattern of relatively deep pockets of soil and regolith, surface bedrock outcrops with little or no soil, and everything in between, overlying an irregular bedrock weathering front. Note also the decreasing degree of rock weathering and fracturing with depth. The soil is relatively thin in most places, with the dark, organic rich A horizon (topsoil) clearly indicated. The browns and yellows in the soil (note the contrast with the rock) are due to formation of iron oxides, which is commonly the case.
Not everything is shown, of course. Unlike a managed forest, where much of the biomass is removed by harvest and much of the remaining “slash” is burned, in an unmanaged forest everything dead falls to the ground and decomposes. There is often a great deal of litter, from freshly fallen to humus (the most advanced stage of plant litter decomposition), and including wood of all sizes (tiny twigs to trunks), leaves (spruce needles in this case), and seeds such as nuts or cones. The painting does show some dead trees on the ground, but after extensive experimentation we determined we couldn’t simultaneously show all the ground litter that would normally be there as well as the other features. However, while the painting is not necessarily typical in this regard, there are sites at any given time with less litter that look like the painting.
Note also that the painting is geographically specific. That is, it represents high-altitude spruce-dominated forests in the Sumava Mountains (which are along Czech Republic’s border with Germany and Austria). It would not necessarily apply to other sites with other trees, or a different environmental setting, though many of the specific phenomena shown are quite common.
The painting is also intended to convey a sense of movement and dynamism. Some of the latter is evident in rocks at various stages of weathering, trees of different ages, dead trees in different states of decay, and thin simple poorly developed along with thicker more highly developed soils.
The following annotated versions of the scene also show various mass and energy fluxes in the upward, downward, and lateral directions. Some processes (e.g., evaporation and transpiration) are invisible, but others are either clearly evident, or more subtly expressed.
More on this to follow . . . .