Skip to main content

geoscience

OCCAM'S SELECTION

Generalized Darwinism holds, in essence, that the principles of variation, selection, and retention (preservation) and replication that are the cornerstone of Darwinian biological evolution are applicable to development and evolution of (to exaggerate only slightly) damn near anything. This perspective, most actively debated in evolutionary economics, is detectable (though sometimes without the specific label) in many science and social science fields.

Generalized Darwinism has many critics, but most critiques I've seen fall into two categories (to simplify and generalize wildly): (1) a lack of fidelity to biological evolution; or (2) an inability to solve every problem in evolutionary economics, system theory, etc.  Those criticisms are accurate, but not valid (in my estimation), as the "generalized" clearly implies a move beyond biological evolution, and no conceptual or analytical framework is ever the answer to everything, even in a relatively small subdiscipline.

MAKING PEACE WITH MACROPORES

The journal Hydrological Processes has recently been publishing a series of articles and commentaries in tribute to the estimable Keith Beven, the recently retired hydrologist from the University of Lancaster. One of his many fundamental contributions has consisted of drawing attention to the importance of, and making fundamental insight into, the phenomenon of macropores and preferential flows. One of those commentaries, by Markus Weiler, addressed these contributions as well as unresolved issues in understanding and simulating preferential flow.

No hillslope hydrologist, geomorphologist or pedologist would dispute the existence or frequent occurrence of preferential water flux in soils, or its importance in many cases at the scales of soil physics to hillslopes. However, Weiler points out that the observed differences in flow pathways at the pedon or hillslope scale are not necessarily detectable at the watershed scale. Does macropore flow matter at the catchment scale? Weiler's answer is yes, though he points out that many scientists believe otherwise.

PROVIDERS OF PREDICTABILITY

From my student days onward, the aspects of nature that interested me most were the apparent anomalies--the things that were uncertain and unpredicted; that weren't like they were supposed to be. Nature contains both regular, ordered, predictable aspects, and irregular, disordered and unpredictable facets. As scientists we are taught to focus on the former and eliminate, ignore, or circumvent the latter.  But anyone who spends much time in the field knows that our planet is a source of infinite variety and ever-increasing uncertainty (because the more you learn, the more you realize that you don't know). But what always fascinated me was not that (for instance) the soils or streams or eastern North Carolina or central Kentucky fit, and can be predicted by, some broad pattern. It was the fact that you can often auger the ground at two spots less than a meter apart and find completely different soils, or walk or canoe a stream channel and easily find features not explained or predicted by the conventional scientific wisdom.

AXIOMS OF GEOMORPHOLOGY

Axiomatic approaches to science and mathematics depend on an underlying set of statements, principles, or propositions that apply to all situations within the domain of study. The axioms run the gamut from undisputed universal laws to widely or even universally accepted but unproved or unprovable generalizations, to propositional stipulations adopted for analytical convenience or because they raise interesting questions.

Examples abound in mathematics and formal logic, and in science, engineering and technological applications of math and logic. Although it is only occasionally referred to as such, the laws of stratigraphy (details in any geology textbook) form an axiomatic approach to sedimentology, sedimentary geology, and related palaeoenvironmental studies. The laws of original horizontality, lateral continuity, superposition, and cross-cutting relationships are assumed in this approach to apply to all sedimentary deposits, and therefore form an axiomatic system for interpretation.

THE BIG FLOOD

In 2011, a massive flood swept through the Lockyer Creek valley in southeast Queensland, Australia. The environmental, economic, and geomorphic impacts were immense, and Australian geoscientists immediately set out to document, understand, and contextualize them. The “Big Flood” project, led by Jacky Croke, has already produced 19 scientific journal articles, and they just this week went live with their web site, with numerous resources for scientists, managers, and the general public.

Floodwaters in Grantham, QLD, 2011 (http://www.thebigflood.com.au/whathappened.html)

The project has already produced some novel results with respect to flood geomorphology and hydrology, and is unique as far as I know with respect to direct efforts to integrate geoscience research with public policy, public education, and practical land and water resource management.

I recommend you check it out.

MORE FOREST BIOGEOMORPHOLOGY & GEOECOLOGY

Imagine exploring and mapping a newly discovered cave opening. At this point, there is only one set of questions--how long, deep, tall, wide, etc. is the passage, and where does it go? But as you begin to map it, more often than not, other passages and fissures will be discovered (and many of them will lead to others, and so on). This opens up a whole new set of questions. Some of the passages can be mapped, assuming someone can get the time and resources. Others can't be no matter how skilled the spelunker; they are too small. But even these can possibly be explored later, perhaps with remote control or AI tiny robots or probes; or with imaging techniques that can see through rock.

This is a pretty good metaphor, I think, for research in general. The more you learn, the more you discover you don't know, and more potential pathways for research appear--some possible now, some awaiting new techniques.

CZECH IT OUT!

A forest biogeomorphology two-fer, courtesy of my central European boyz, who have graciously allowed me to ride their coattails here in the twilight of my career. The first is one where Pavel Daněk took some of my ideas and methods on applying graph theory to soil geomorphology, and went places with them I never even imagined:

Daněk, P., Šamonil, P., Phillips, J.D., 2016. Geomorphic controls of soil spatial complexity in a primeval mountain forest in the Czech Republic. Geomorphology 273: 280-291.

The second is one  that arose when Pavel Samonil took me to one of his field sites, where I saw things I hadn't imagined:

Phillips, J.D., Šamonil, P., Pawlik, L., Trochta, J., Daněk, P., 2017.  Domination of Hillslope Denudation by Tree Uprooting in an Old-Growth Forest. Geomorphology 276: 27-36.

The abstracts are below.

 

 

ON BEING WIDELY IGNORED (OR NOT)

In the brief biography on my departmental web page, I refer to myself as the "author of a vast number of widely-ignored articles."  This statement reflects the lifelong tug-of-war between my inherent boastful, egotistical leanings and the humility my parents tried, with mixed success, to instill. Thus the boastful "vast number" juxtaposed with the humble "widely ignored." The latter, by the way, is based on the relatively low number of citations and other metrics generated by ISI, etc., compared to the most popular and influential scholars.

I revisit this because I got an e-mail from a master's student working on a research paper who asked: "When going through the bio section of the webpage for the university you work for, it says that a lot of your work is widely ignored.  I am wondering why this is, as I have seen some of your work and think it is fascinating.  Maybe you could help me in this matter by explaining a little further?" The egomaniac within wants to answer that it is because I am so far out front that few have caught up with me; a genius-ahead-of-his-time narrative. The answer dictated by my upbringing (which in this regard is typical for anyone of my generation raised in the small-town or rural USA) is that I just need to try harder and do better (and thanks for the compliment!).

HURRICANE MATTHEW & FOREST BIOGEOMORPHOLOGY

Hurricane Matthew devastated Haiti and other Caribbean areas, and did tremendous damage in Florida and South Carolina (I rode out the storm in Myrtle Beach, SC with my son Nate, his wife Morgan, and my delightful 2-year-old granddaughter Caroline). By the time it got to North Carolina, winds were down to gale force, but rain was ferocious (15 to 40 cm) in much of eastern N.C. Where I am at the moment, in Croatan, there was "only" about 10 cm of rain, and only gale force winds. However, that was enough, as it usually is, to get some geomorphic work done in the forest.

Below are some photos of trees uprooted by the storm in Croatan National Forest in the Flanner Beach area. Uprooting not only does significant soil mixing, but the pit-mound topography left behind significantly influences hillslope and soil processes for decades (and occasionally longer) thereafter.

Another example from a cemetery near Maysville, N.C.

The Perpetual Quest for Efficiency Part 3: Why Isn’t Everything Always Becoming More Efficient?

(Part 1 here; Part 2 here)

The principle of gradient selection, along with a variety of “optimality” principles in geomorphology, geophysics, hydrology, and ecology (e.g., Patten, 1995; Fath et al., 2001; Lapenis, 2002; Ozawa et al., 2003; Kleidon et al., 2010; Quijano and Lin, 2014), is in essence a particular case of a broader principle of efficiency selection. Given this common behavior in many types of Earth surface systems, why do we not observe a general global trend toward ever more efficient routes and networks of flows?

First, note that gradient and efficiency selection are tendencies that (like natural selection in biological evolution) apply in the aggregate, and not to individual cases. Also recall from part 2 that gradient selection is imperfect even where it operates.

Subscribe to geoscience