The Dirt on Enchanted Rock, TX

An honor to be climbing with The Prez of the Texas Invasive Plant and Pest Council and The Lady that is responsible for my love of science (and wavy hair)

So, me and some lovies went to Enchanted Rock, Texas.  It reminded me of my last trip to Enchanted Rock, wayyyy too long ago with a precious godmother, or madrina, who was visiting for a baptism circa the spring equinox.  I also have many a memory of camping here during college.  Ergo, during this hike, I was twice filled with The Love: the lovies of the present, and the lovies of the past.    I will spare you the relevant Sesame Street video, but let's all agree, climbing Enchanted Rock is fun.

What is Enchanted Rock?  It is a big granite intrusion.  It's most common minerals, I believe, are microcline, plagioclase, quartz, and biotite.  You can follow a geological tour up the hill, it's nice.

Schmanyways, obvs there are associated soil photos, but first (!!!) here is what Enchanted Rock looks like from the road.

Since Texas is unfairly known for being quite flat, this is kindof a big deal.  Look, a protuberance!

A closer peek...

We climbed to the top and had some cool views.  

Forgive me because I have lots of pictures I want to share about an obsession I didn't really know I had: plants appearing to grow out of rocks (!!!).  

People in the know are calling them vernal pools.  Vernal pool ecology is created by pioneer species: they are the first to colonize a mostly abiotic area.

I like this pic: this is a vernal pool - the first inklings of entisol soil formation.

I think  that is an oak tree.  Sorry for my photo smidge on the right.  

Looking uphill, presumably native grass.

Same area.

Some cactus.

Spatial distribution.

The top.

According to the Texas Parks and Wildlife Department, the plants and animals that live here are "uniquely adapted to a harsh environment."

In fact, by studying weather pits, ecologists learn: (1) how plants and animals colonize a newly formed habitat;  (2) how those organisms modify their environment and help develop soils; and, (3) how plant and animal community structure and composition change over time.

In other words, they are super neat.

At Enchanted Rock you can see the progressive development from bare rock-bottom pits, to annual plant establishment, to miniature prairies with grasses like little bluestem and even trees like live oak. Vernal pools also support an interesting species of invertebrate, the fairy shrimp. These tiny animals survive total desiccation as fertilized eggs, and hatch into larvae and grow into adults each time water collects after sufficient rainfall.

Since these things are super cool, and their ecosystems are so fragile, the Texas Parks and Wildlife Department wants to make sure visitors are aware of their significance and asks them to back off. 

"STAY ON THE ROCK," they say.  And, 

"Thank you for protecting an important part of the Enchanted Rock experience."  

Look at the length of the root compared to the height of the above-ground portion (green leaves only).  This was on the bank of a dry creek bed.

Have a great visit!

P S.  Natural resources of Enchanted rock found here.

Six Degrees of Separation: Smectite Style

Hello, my dearest little poblano peppers!

How are you today?  Where are you today?  You know, I clicked on something according to my research, there are twelve whole readers of you out there. TWELVE of you that lovingly indulge me with a subscription!  I thank our usual suspects, Dr. Doyle, Soilduck, GonferalinID, and Layla.  And you others aren't my mom or dad (well, two of you are, but you don't actually subscribe, LOVE YOU!), so... who are you? Please let me know, so instead of me talking about soils I encounter, we can talk about our soils.  For example, uno de mis amigos vive en un ultisol importante, y otro vive sobre de  roca y un poco suelo (his guest post here).

So please, will you comment and introduce yourself?  Or what you want to hear about next? Or a random thought? I'll pause and wait, to give you a moment to do that....

Waiting for you to comment gives me similar existential issues as those confronted by Grover and Telly Monster in "Waiting for Godot Elmo" by Sesame Street's Monsterpiece Theater. 

Moving on, I have this little "6 degrees of soil separation" game going on in my head all the time.  I believe you can link anything back to soil, just like Kevin Bacon.  So today I am going to relate annoying small toads to the chemical structure of smectite*. I know, it's magic!  Thank you ;-)

First of all, let us let us focus our attention on a gentle, young, unsuspecting Bufo valliceps toad.

Actually, he indeed suspects, see why below.

According to my research hubs, this toad is a Bufo Valliceps. I like to water my foundation, catch them, and gawk at them adoringly.  I pour water onto the side of my house and they all come jumping out from the crack between the foundation and the soil. 

You see, when it doesn't rain, my clay shrinks to provide these naifs space to cuddle in a nice, moist resting area. 

And when it doesn't rain, I water my foundation to get rid of the very same crack in which they reside (Does it help your foundation stability for reals? No idea).

You see, this toad and my humble abode are located upon a smectite clay. I'm obsessed Perhaps you have heard of this soil here, here and here.  Anyways, the crystal pattern for smectite involves adjacent planes, or sheets of oxygen (among other elements).  And adjacent oxygens don’t “bond” with each other very strongly compared to say, hydrogen bonding [the polarity of water: discuss].  This means that when precipitation (rain) percolates into the soil, fresh soil water molecules have an opportunity to get all up in between the tetrahedal layers, which pushes the layers apart and increases the soil volume(!!!).  Yes dude, the soil gets bigger, and in an annoyingly uneven way.  "Le sigh," says my house.

Imagine, the soil under your house is a smectitic, and whenever it rains, the clay under your house expands, and shrinks when it doesn't.  It is like building on ... some other slowly flowing (viscous) material.  Your walls may crack, your door jams stick.  Anyways, we water it in a futile? effort at keeping soil moisture nice and even at all times, which should supposedly preserve our foundation's integrity.  And this is where the toads come in again.

In conclusion, our 6 degrees of Kevin Bacon separation:

1. I pour water onto the soil next to my house foundation so that it will expand to close the crack between the two.  Toads hop out of the crack, annoyed (and then I catch them!).  You see,
2. Maintaining near constant soil moisture levels may preserve our foundation located on a smectite clay. 
3. Smectites change volume depending on soil moisture, 
4. Cuz their adjacent tetrahedral layers are only bonded by oxygen bonds and 
5. Water is more electrostatically attracted to the oxygens in between the tetrahedral layers than the oxygens are to each other.  
6. Once hydrated, the smectite clay mineral expands with the added molecules.

Ta da!  You too, can use your soil science expertise to mildly inconvenience small animals!

PS These smectitic soils are characterized by high base saturation, partially explained here and here.  

Definiciones:

Smectite: A mineral found in great quantities in vertisols, which are known for their shrink swell capacity due to expanding 2:1 lattice clays (source).
Phyllosilicates: Silicates (atomic structures featuring silicon) that combine to form planar sheets.
P.S. They discovered phylosilicates on Mars.  

ATX: Your poo promotes birdwatching. Indirectly.

Birdwatching at Hornsby Bend (Photo credit: Meredith O'Reilly)

Hornsby Bend, Austin’s premier birding location, is a biosolids recycling facility.  

Say what? Your beatific contribution to the sewer system via flushing toilet travels through pipes and goes to a wastewater treatment plant. After treatment, the biosolids (or, if you want to sound like a nerd, primary and secondary waste-activated sludges) go to Hornsby Bend, where they are manipulated again ultimately composted with yard trimmings collected from Austinites to make Dillo Dirt (Read page 3 of this doc for more details on how this is done.)  The liquid waste portion of the biosolids make outdoor ponds, whose waters irrigate onsite fields.  

The birds love Hornsby Bend.  They like the ponds, the drying basins, woods and fields:

The biodiversity is present both because of the nutrient rich biosolids treatment  processes used by the facility and because of the diversity of habitats at the site stretching along 3 miles of the Colorado River. (source)

We built it, so they came, enjoyed, and returned.  And now we can go watch them. Meredith at GreatStems wrote a very nice blog post on Honsby Bend's birdwatching and history.

If you haven’t had a chance to visit Hornsby Bend's neat avian-friendly ecosystem, you should fer reals go. 

Here are some visiting tips:

Hornsby Bend Map

Location Descriptions: Where to see What

Seasonal Guide

You can go by your lonesome or join the group activities as listed on The Dirt on Soil's calendar, which include:

• A monthly bird survey every 2nd Saturday of the month @ 7am,
• Birder led "field trips" every 3rd Saturday of the month, and
• Eco-literacy day every 4th Saturday of the month @ 9am -1pm
• 3 hours of outdoor volunteer work; 1 hour of ecological education

Also, Hornsby Bend is open daily to the public from sunrise to suneset.

The Saaaands are Alive with The Sound of Muuuuusic!

This post reminds me of that lovely Julie Andrews song, parodied here.

Dear Readers (How are you?),
I confess: I've been pretty biased against sand.  Hydrologically speaking (which is totally my paradigm), I consider it the boring soil texture of the three (sand, silt, clay).  Por ejemplo:

• Water flows through it the easiest (of sand, silt and clay), meaning is has the highest hydraulic conductivity*, and 
• it holds onto the fewest nutrients because of it's low cation exchange capacity* (I mention CEC here and here).  
• Also, it's soil moisture curve* leaves much to be desired.  I mean look,

(image source, from an awesome looking lecture on soil water relationships in soil)

Just look at how quickly sand loses it's soil moisture when the water table drops (shown on the x-axis).  Yawn, right? Clay holds onto it's water!! Jeez.


But recently, I came to terms with the idea that maybe sand was more interesting than I thought.  A few weekends ago, we saw some familia in Corpus Christi, TX and went to Padre Island National Seashore (Click here for map). As in, we went to the beach, where you get to play in nothing but pure, boring, bland sand.  So you'd think I'd be bored out of my mind there, but lo, it was not true.

Mi familia y yo started digging in the sand of the intertidal zone, and did some learning (BTW,  sandcastles, sand-chairs, and drip mountains are totally learning.)

This is South Padre Island National Seashore's intertidal (IT) zone*.  The IT zone here would be everything in between the seaweed piles to the low tide waves.  An IT ecology lesson here.

Wanna know what we saw?  Aliens!  Just kidding: one long, skinny worm, tonsa things that looked like dark, stubby worms, a decapod (a ten-footed something-or-other, shrimp?), and something that looked like a "sand crab" to my untrained eye.  Kinda like everything on this marine science page (seriously, look at the cool pictures!).

This is a blood worm (genus Euzonus), which might be what I saw (Image credit).

So, in conclusion, the sand is alive!   These creatures have ecological importance as nutrient recyclers, just like our soil brethren.  For example, can you believe, and I quote:

Some worms called polychaetes [my note: this is a class of worms that inlcude the Euzonus genus] simply eat the sand whole and let their digestive systems clean it off. Out the back end, eventually, comes a trail of clean sand (source).

More:

Blood worms function on the sandy beach much like the earth worms do on land — they ingest the sediments (sand for the blood worms) and digest the organic material found between the sand grains. This type of feeding is called deposit feeding and results in a type of "cleaning" of the sediments. (source) 

You mean they poo a trail of clean sand!?!? Awesome.  So, why are we thankful for tiny sand creatures?  They don't cause diseases and they clean up after our organic mess.  HUGS YOU, little sand creatures!!!

And to you, Sand: I'm sorry for thinking you were boring.  I love your interstitial fauna* and you are easier to wash off our hands than clay.  Thank you, too :-)

***UPDATE***
It turns out that sand is waaaaay more interesting than I thought.  Check out this book review blog post by Brian Romans on the book Sand by Michale Wellans.  This author also has a SAND BLOG on all things sand!  Now back to your regular programming...

*Definiciones:
Intertidal zone: The transitional coastal region located between high and low tide marks (source).
Hydraulic conductivity: "A measure of the capacity for a rock or soil to transmit water; generally has the units of feet/day or cm/sec (source)," or "The ease of movement of water through the soil relative to a potential gradient (source)." Think of a potential gradient as a difference in water table levels: water flows from high to low water table levels.
Cation Exchange Capacity: "a measure of the negative charge on soils (primarily on clays and organic matter). It is expressed as the quantity of cations (positive ions) that can be adsorbed by the soil (source)."
Soil moisture curve: a graph that shows the relationship between soil moisture content and pressure head (aka water table draw-down).
Interstitial fauna (meiofauna): the tiny animals that live in between the sand grains.  Also "loosely defined as animals capable of passing through a 0.5-mm mesh (source)"

So, Did You Know That Moss is an Ecological Indicator*?

I was walking with my chickfriend (not to be confused with chiksa, even though she is one of those too) the other day, and we happened upon what I will call moss (Is it moss? I don't know; I'm a geologist!).  It was growing on the sidewalk downtown, under a gutter!

Photo courtesy of my chickfriend Sarah Kerver

For reals, where is your soil, Little Moss?  How do you live so bright and happy under a drain spout?  On top of cement, apparently very satisfied with the nutrients provided by the accumulation of dust that deposits underneath you?

So it inspired me to look up info on this plant that reminds me of ... my verdant childhood (Maryland has more moss than Texas.  Our loss).

So what is moss? Here are some basic factoidals.   They are not to be confused with lichens, more on those here.  The neat part is, they get many nutrients from rainwater, not soil.  However, if the rain droplets are falling through polluted air before they reach the moss (I wish the plural for moss was meece!), it will more likely disturb the moss faster than it will other plants.  In fact, moss is a good indicator of air pollution Why? Here is a good quotation from Kevin J. Lyman of the Milkwaukee Public Museum:

Why are mosses and lichens sensitive to air pollution? Since mosses and lichens lack roots, surface absorption of rainfall is the only means of obtaining vital nutrients which are dissolved in rainwater. Lichens and many mosses lack protective surfaces that can selectively block out elements including pollutants that are dissolved in rainwater.

So, it looks like finding happy moss in the middle of downtown ATX is a good sign!  Hopefully this does mean that the air around the moss is clean :-)

Wanna grow your own moss? Try reading here first.  Enjoy!

*Definiciones:
Ecological indicator: as discussed in another ecological indicator post on a toad, it is a measure of the environment (e.g. the presence/absence of an organism)  that is used to evaluate the health of an ecosystem (more technical definition here). 

My Morning in Pictures: Soil's Eye View.

Beet seedlings' eye view.

Driveway's eye view.

My favorite maggots

The adult soldier fly.  Photo credit: Rock Hill high School

Howdy neighbors!  How is your soil today!?

I need to tell you about my new favorite pet, the soldier fly larvae.  I'm being totally serious.  I worry about their health!  When I go to my compost tumbler to drop off a new gift, and see hundreds of them chewing on my food scraps, I get so relieved. Yay, they are still there!  Phew! Now that I have them, I don't know what I'll do without them.  Well, I do- I'll actually have to exert myself and turn my compost instead of just gawking at it lovingly.  Don't leave me, maggots!  I love how your efficiency enables my laziness!

 See them in their gross glory here (click play):

Look at the smiles on those happy Hermetia illucens.  That was once an avocado, by the way.

The best part about my maggots is that I pretty much do nothing to keep them around.  They are lower maintenance than chickens!!  My compost tumbler system is set up well to house them, because I can keep fresh kitchen scraps on the top of my pile, inside the tumbler, and attract the soldier flies without attracting rodents. 

Factoids about my new Friends

• Heterotrophes*, and detritivores*, these baby solider flies eat rotting things (like my kitchen scraps) like it is their mission in life.  They'll take big uncut (read: lazy compost style) chunks of whatever and turn it into homogenous poo so it can further decompose into awesome humus.  Ergo, they help me make compost faster.  A lot faster.  For example, before these guys, we called my tumbler "the preserver" since we wouldn't get but one binful of humus a year. Now I'm depositing pretty-smelling bug poo on my soil that was food just a few weeks prior.
• They are voracious and will likely  eat scraps before they have a chance to smell badly (even big compost no-nos like dairy, shhhh).
• Their poo is a nice smelling soil amendment. Mmmmm bug poo smells like actinomycetes.
• The adult soldier flies do not eat.  This means that unlike the maligned cockroach and house fly (yuk!), they don't come into your house looking for food! If they are in your house, they are lost; they don't want to be in there!  Unless you have rotting food in your house, but that is another discussion (you should clean your house *cough*).
• The flies inoculate the compost with beneficial bacteria.
• They are native.
• They don't bite or carry disease (source)!
• They outcompete houseflies for habitat, reducing your housefly population.  

Gratuitous macro lense house fly pic:  I am not a fan of this diptera (Diptera is the order that characterizes both flies).

Soldier flies have so many interesting positive attributes, that Dr. Watson and others are looking into utilizing them for large scale animal waste  management.  

Yay!!!  Tell me about the bugs in your soil that YOU are grateful for!

*Definiciones:
Autotroph: "The acquisition of metabolic energy from the fixation of inorganic carbon, for example, by photo- or chemosynthesis (source)."
Heterotroph: "An organism that depends on complex organic substances for nutrition (source)."
Detritivore: "An organism that feeds on dead organic debris (source)."

My Friday in Pictures

Yesterday, I helped at American Youthworks' inaugural "drainage ditch" garden groundbreaking.  

An American Youthworks teacher gardens.

Since the gardens are in the drainage ditch, they are watered by rain and from upstream surface and ground water flow.  The plants are in raised beds, adding water drainage and preventing their flooding during periods of heavy rain.  

This garden is in an urban environment, which has  hydrological consequences.  As a  small scale watershed quality strategy, we made sure to put  mulch (e.g. pine needles) on all bare areas.  

We weeded and sowed Fall appropriate seeds.  The shadow of yours truly is in the bottom left corner.

A look at their compost pile behind the basil.

This is one of my favorite pics from the day.  These little garden blessings were placed all around the garden.

I hope you are having a great weekend!  Tell me about it in the comments!

The dirt on turning soil into plants: August edition

OK, you got me:

"A plant's dry matter* consists mostly of carbon, hydrogen, and oxygen, which the plant obtains by photosynthesis from air and water, not from the soil.  (Reference #1)"

But the other macronutrients*, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur, mostly come from soil solids.

As fascinating as soil is, much of my relationship with it is in the "benign neglect" category.  I'm hoping to change that!  But it is August and it is hot.  What to do in Central Texas?

Texas Agrilife Extension Service gives us a 2010 Travis County Planting Calendar, a list of vegetable varieties, and seed sources. Since today is August 26, the chart says I still have time to plant beans (lima and snap), cucumber, and summer squash.  And maybe I could squeeze in some Irish potatoes.  So I looked into my seed stash, and here is what I did:

• Planted cucumber and bush bean seeds.
• Covered them with my low-maintenance, wabi-sabi, I-don't-really-pay-attention-to-it compost.
• Watered them lightly.  Thought of our abnormally dry conditions.  Considered the feasibility of graywater.
• Looked around for potato seed resources, and found some awesome potato literature from Agrilife, University of Illinois Extension, and NCSU.  Also, Gone Feral in Idaho uses a potato box.  Looks easy, maybe I'll try it!  Then I realized seed potatoes are hard to find until their spring planting season.   

How is your soil today?  How are you showing the soil your love?

*Definiciones:

Dry matter: "

the percentage of plant sample, which 

remains after all the water, has been removed (Reference: Cooperative Extension Service University of Kentucky and Kentucky State University)."

Macronutrients: "A chemical element necessary in large amounts (usually 50 mg/kg in the plant) for the growth of plants (Reference #1)."

11 things you can do to increase water in Austin creeks

This creek has high water flow during rain events; you can see the big pile of brush that the water carried.  But a day later,  it is sunny and the creek is dry (Fort Branch Watershed at Springdale Rd., I think).

We talked earlier about how one of the problems in local Austin streams is that they have too much water when it rains [which renders our poor froggies and fish practically habitat-less from all that turbulence], but not enough the rest of the time.  This, in part, is caused by how we have developed impermeable cover on top of our soil.  Basically, we've become urban.  For more details, please read my post on Watersheds in a nutshell in a nutshell.  Thanks!  Now onto the proactivity...

There are ways we can help those little froggies and fish keep their homes, and it doesn't have to be done by big groups of people.  Each yard can make a difference!  All we have to do is point water in a new direction, away from runoff and evaporation, and towards infiltration into the soil and groundwater.  When water is supplied to creeks by  groundwater recharge instead of runoff, creeks flow at a more constant rate.  A more constant flow rate helps preserve aquatic habitat.

Below are some tips directly from the City of Austin's Watershed Protection Department and the EPA that will help our creeks flow.

Structural improvements:

• Divert rooftop runoff to vegetated areas rather than pavement (source).  This is called rainwater harvesting.
• Minimize pavement: use wood decking, bricks or interlocking stones for walkways and driveways (source).
• Consider creating grass swales (low areas in the lawn).
• Install gravel trenches along driveways or patios.
• Make a rain garden- Rain garden instructions
• Collect your rainwater to use later - Rainwater harvesting instructions

Plants:

• Select yard plants that have low requirements for water.
• Preserve existing trees, and plant trees and shrubs.
• Irrigate efficiently to avoid runoff from your yard (source).  For example, using "slow-watering techniques such as trickle irrigation or soaker hoses reduce runoff and are 20 percent more effective than sprinklers." (Thanks, EPA!)

Ground cover:

• Spread mulch on bare ground or restore bare patches in your lawn.
• Use compost. Compost retains moisture in the soil and thus helps you conserve water.

Increasing vegetation and ground covers are doubly effective.  They increase infiltration, and they also reduce evaporation!  Increased evaporation from impermeable ground surface is an often forgotten result of the increased urbanization of our watersheds.  By increasing shade, and thereby decreasing heat, we reduce evaporation (click here for more physic-sy evaporation details and terminology, just scroll down on the right side and look for terms).  This way, the water stays longer right where we want it, it our watershed!

What about you?  Do you have other tips?  This is Austin, so we can be creative!

***UPDATE!!!***

Here is a 12th, amazing extra credit thing you can do: Create a green roof!  Thanks for the idea, Wildflower Center!

It was hot today: the dirt on the heat index.

Fer reals.  The National Weather Service predicted that it would feel like 110°F (Fahrenheit) today.  Same for tomorrow, I hear.  This does not bode well for the following polar bear:

Maryland: Where men are almost as tall as mountains.

What are they saying when they predict it will feel like 110°F, even if it is only [only: ha!] 102°F?  They are talking about the Heat Index.  At first I thought it was the same as the term "effective temperature".  Oh, but no; when I looked up that definition, I got this from Columbia University: 

The effective temperature of a planet is the temperature it would have if it acted like a black body, absorbing all the incoming radiation received at its surface and reradiating it all back to space.

That's not what I want! This is what I was looking for, from NOAA's National Weather Service:

The Heat Index (HI) or the "Apparent Temperature" is an accurate measure of how hot it really feels when the Relative Humidity (RH) is added to the actual air temperature.

Please click on their link for all the details, it is pretty good text, but in the mean time, here is my favorite part:

The body's blood is circulated closer to the skin's surface, and excess heat drains off into the cooler atmosphere by one or a combination of three ways...

• radiation,
• convection, and
• evaporation.

At lower temperatures, radiation and convection are efficient methods of removing heat. However, once the air temperature reaches 95°F (35°C), heat loss by radiation and convection ceases. It is at this point that heat loss by sweating becomes all-important. But sweating, by itself, does nothing to cool the body, unless the water is removed by evaporation (sweat changing to water vapor). The downside of this method of cooling is that high relative humidity retards evaporation.  (reference link)

Considering their explanation, I'm surprised that wind speed isn't factored into it.   Doesn't wind promote evaporation?  Cuzzzzzz it blows the humidity away?  


But here is a funny thing part: the heat index was first introduced by R.G. Steadman (1979) in his document called  "The Assessment of Sultriness, Parts 1 and 2." 


Sultriness. Hee!

Definitions are funny

I wanted to talk about the difference between soil and rocks, but when I started looking up definitions, I remembered that there isn't a singular definition on which we all agree for these things.  The definition of a word depends on who you talk to, and the definitions bleed into one another.  

Geology
For example, I happened upon the knowledge that the classic definition of geology is the study of the earth. 


The study. 
Of the earth.  (Doesn't that kinda mean everything? Doesn't the study of the earth also mean economics and anthropology and religion?)
And its life forms, and the evolution of life.  
Which now sounds more like biology.  


To be honest, I like this definition.  Cuz I think that geology does include the study life and its evolution (for example, paleontology), but only as it has been recorded in the rock record.  But what are rocks?

Rock
Please click here for the definition of "rock, " courtesy of the US Geological Survey (USGS).  Notice they use the word "mineral."  What are those?

Mineral
Please read the definition "mineral,"  by the Soil Science Society of America (SSSA)- "a naturally occurring homogeneous solid, inorganically formed, with a definite chemical composition and an ordered atomic arrangement."  

Oh, but no! The USGS begs to differ.  They are more specific than the SSSA's "homogeneous solid," calling it an element or compound instead.  I like this better.  Also, "the ordered atomic arrangement" is called a "crystal form" by the USGS.   Same difference.

I know.  Tedious.


Soil
Anyways, here are soil definitions, courtesy of the NRCS.

Here is some mica.  Common in the Glenelg silt loam in Maryland.  Use fingerprints for scale.

What I get, is that soil has rocks in it, but soil is also an ecosystem.  There is air, liquids, and solids in soil.  There is water, there are minerals.  There is representation from all taxonomic kingdoms of life.  Oh and look, there is also my heart and soul (transcendent violins, please! And an angelic chorus).