The development and change over time (evolution) of geomorphic, soil, hydrological, and ecosystems (Earth surface systems; ESS) is often, perhaps mostly, characterized by multiple potential developmental trajectories. That is, rather than an inevitable monotonic progression toward a single stable state or climax or mature form, often there exist multiple stable states or potentially unstable outcomes, and multiple possible developmental pathways. Until late in the 20th century, basic tenets of geosciences, ecology, and pedology emphasized single-path, single-outcome conceptual models such as classical vegetation succession; development of mature, climax, or zonal soils; or attainment of steady-state or some other form of stable equilibrium. As evidence accumulated of ESS evolution with, e.g., nonequilibrium dynamics, alternative stable states, divergent evolution, and path dependency, the "headline" was the existence of > 2 potential pathways, contesting and contrasting with the single-path frameworks. Now it is appropriate to address the question of why the number of actually observed pathways is relatively small.The purpose of this post is to explore why some developmental sequences are rare vs. common; why some are non-recurring (path extinction), and some are reinforced.

Brad's Blurb

This month I will start out with a couple of really lame jokes.

*What did one snowman say to another?  Is it just me or do you smell carrots!

**What do you get when you cross a snowman with a vampire?  Frostbite.

***Where do snowmen keep their money?  In a snow bank. 

Do you remember the time before computers?  Me neither.  If you are young enough, computers have been around your whole life.  If you are old enough, your memory is not as good as it used to be.  I fall in the latter category.  The Internet/Web for me is like my car; I use it all the time and expect it to work all the time, but I don’t really have any idea how it actually works.  Which leads me to some questions?  

-How did the Internet get started?  See 1

-Who’s in charge of it?   See 2

-What is the difference between the Web and the Internet? See 3

-Who is the keeper of all URLs (website addresses)? See 2

-How many websites exist?  See 4

-What are the top 10 websites based on traffic? See 5

1. In 1989 Tim Berners-Lee wrote a proposal for a system called the World Wide Web.  He then wrote the first web browser, server, and Web page.  He also wrote the first specifications for URLs, HTTP, and HTML. 


In a 2009 article I introduced the concept of a geomorphological niche, defined as the resources available to drive or support a particular geomorphic process (the concept has not caught on). The niche is defined in terms of a landscape evolution space (LES), given by

where H is height above a base level, rho is the density of the geological parent material, g is the gravity constant, and A is surface area. The k’s are factors representing the inputs of solar energy and precipitation, and Pgrepresents the geomorphically significant proportion of biological productivity (see this for the  background and justification).

Martha Tilson - Experience Undergraduate Research @ UK

Meet Martha Tillson, a non-traditional Senior majoring in Social Work & Psychology. Listen to how undergraduate research impacted her college experience at the University of Kentucky.


Inside the Classroom: Susan Odom’s Organic Chemistry Lab

Take a look inside on our Arts and Sciences Organic Chemistry Labs.

UK @ the Half: Arny Stromberg, Department of Statistics

UK @ the Half: Arny Stromberg, Department of Statistics


Just published in Geomorphology:

Samonil, P., Danek, P., Adam, D., Phillips, J.D. 2017. Breakage or uprooting: how tree death affects hillslope processes in old-growth temperate forestsGeomorphology 299: 276-284. 

The abstract is below:

Posted 14 November 2017


Brad's Blurb

Planes, Trains and Automobiles Thanksgiving

I am going to use this edition to write about a family tradition that I am looking forward to during the Thanksgiving break-watching the film classic from director John Hughes, Planes, Trains, and Automobiles (1988).  The movie stars John Candy and Steve Martin.  Although, not necessarily “one for the kids” based on some very colorful language (one particular scene between Steve Martin and a car rental agent), the movie has a memorable ending that might just leave you feeling a little contemplative about Thanksgiving.  Some other notables you might recognize with bit parts in the movie include: Kevin Bacon, Dylan Baker, Ben Stein, Edie McClurg, Michael McKean, and Ruth De Sosa. 

MCLLC and Hispanic Studies World Language Day 2017 Alumni-Student Panel

Alumni from Modern & Classical Languages, Literatures & Cultures and from Hispanic Studies discuss their career paths in education, business and state government and the role language study has played in their professional and personal lives. Three current UK students talk about their research, their study abroad experience and their community service. 



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