Environmental Benefits Assessments for USDA Conservation Reserve Program

The USDA uses an  Environmental Benefits Index (EBI) to rank Conservation Reserve Program land applications by prioritizing soil conservation, water quality, and wildlife habitat.  Six factors are considered:

1. Wildlife habitat benefits resulting from covers on contract acreage 
2. Water quality benefits from reduced erosion, runoff and leaching 
3. On-farm benefits from reduced erosion 
4. Benefits that will likely endure beyond the contract period 
5. Air quality benefits from reduced wind erosion
6. Cost

1.  Wildlife habitat is determined by looking at planting composition (introduced or native), number and composition of species (more species, and more functional groups such as legumes, shrubs, trees, forbs, and grasses have higher value), and landscape context (strips, blocks or mixtures that form corridors or gaps).  Points are also available for providing pollinator habitat and for enhancing wildlife in areas high-priority areas.

2.  Water quality benefits are determined by whether or not the property is in a designated surface water quality impairment zone, the type of soil, potential soil erosion, and distance to major waterbodies.

3.  Not discussed.

4.  Enduring benefits are determined subjectively based on the probability that conservation will continue beyond the CRP contract.  For example, trees would be expected to live longer than the 10-year CRP contract.

5.  Air quality benefits are determined by calculating potential wind erosion (based on average wind speed and soil texture), whether the property is in a air quality nonattainment area, and the potential to sequester carbon in the soil by planting trees, shrubs, or grass.

For more information, see the CRP Farm Science Administration website at USDA.gov.


....USDA also periodically reviews the effectiveness of their programs using the Conservation Effects Assessment Project.  Data and papers can be found here.

Hydrophobic soils after fire? All soils are more or less hydrophobic...

As explained by "Geomorphology: Themes and Trends".  The book is worth it just for the classic essay on erosion and runoff.  A combination, it turns out, of pore size and particle characteristics.

These images are from Chapter 5, "Geomorphological processes, soil structure, and ecology" written by A.C Imeson.  Yes, the x-axis is scaled as square-rooted minutes.

Plant roots can change both the permeability and wettability of soil (as well as many other qualities).  For more information, read Reid, TB and Goss, MJ. 1981.  Effect of living roots of different plant species on the aggregate stability of two arable soils.  Journal of Soil Science.

The book also has a chapter on the Geomorphology of stream channels and craters on Mars!

Environmental Degradation in Haiti

Google maps has high-quality satellite imagery of Haiti, and reading remote-sensing images is a big part of my job as an ecologist so I decided to take a brief fly-over to see what it looks like. What immediately called out to me was the widespread and obvious degradation of the rivers and streams; the images of Haiti are consistent with a highly disturbed landscape. Most unconfined rivers in Haiti appear braided, meandering over large areas of bare ground.

These rivers are rapidly aggrading (depositing sediment), most likely due to excess sediment from erosion in the uplands. Of course, natural disturbances such as hurricanes, forest fires, and perhaps even earthquakes, could cause similar river channel adjustments. Braided channels may be a natural response to naturally high-erosional areas. Here is such a stream in Southern California:

If Haiti had a Californian/Mediterranean climate instead of a Carribean climate, these levels of disturbance could be explained naturally. Instead, these high-disturbance, silt-choked rivers and streams are likely better explained by human overuse and consequent environmental degradation: "Haiti...was largely self-sufficient in grain 40 years ago. In the years since, though, it has lost nearly all its forests and much of its topsoil, forcing the country to import more than half of its grain." Brown, Lester R. "Could food shortages bring down civilization?" Scientific American. May 2009. p. 50




Closeup view of wide, unvegetated floodplain in Haiti:

Of course, Haiti is not the only place with altered erosion visible from space. In fact, the images above are becoming the norm across much of the world. Even richer countries have impacted rivers, but some, such as Costa Rica, also have many rivers that are allowed to remain in their unimpacted, natural state. This is what tropical rivers should look like when they have a natural disturbance regime:

Quivira Coalition Water Symposium

Quivira Coalition Annual Conference


Speakers I enjoyed:

Peter Warshall
A-->B Horizon (CF. History of Greece)
some grasses like B horizon (maybe Hairy Grama?)
1,000 years to restore
Vigil network data
Leopold was against "drop-in science"

Larry Schmidt
--> channel incision
lack of sediment incises below stream
-->too much water (culverts)
-->too much slope
-->wildfire causes no cover, hydrophobic soil, runoff w/out sediment
results in incised channel (sediment hungry)
positive feedback between reduced cover, dendritic incision, and loss of wateravailability

Burchard Heede Alkali Creek 40 years
showed that landscape incision could be corrected by creating a grass-lined waterway
induced meandering can also cure incision

Bill Zeedyk and Van Clothier
streams can erode bottom OR sides
*anticipate* stable form
*nudge* in that direction

e.g meander multiplier is usually between 10-20: 10 for wet sedge meadows, 18 for dry ephemeral channels
Questions:
utility of BF-FP width ratio?
how does flow become channelized (versus dispersed)
why aren't incising channels self-correcting? are they?
structures needed b/c of lack of woody debris?

Gallinas Peak, or, on the Topographic Asymetry of Mountains

Topographic Signature of life, or ice:


Which is steeper: North Face (ice shaped) vs, South Face (life shaped)?



"Without life, there would still be asymmetric mountains. Rainfall patterns affect the height, width and symmetry of mountains.


Landscapes are shaped by the uplift, deformation and breakdown of bedrock and the erosion, transport and deposition of sediment. Life is important in all of these processes. Over short timescales, the impact of life is quite apparent: rock weathering, soil formation and erosion, slope stability and river dynamics are directly influenced by biotic processes that mediate chemical reactions, dilate soil, disrupt the ground surface and add strength with a weave of roots. Over geologic time, biotic effects are less obvious but equally important: biota affect climate, and climatic conditions dictate the mechanisms and rates of erosion that control topographic evolution. Apart from the obvious influence of humans, does the resulting landscape bear an unmistakable stamp of life? The influence of life on topography is a topic that has remained largely unexplored. Erosion laws that explicitly include biotic effects are needed to explore how intrinsically small-scale biotic processes can influence the form of entire landscapes, and to determine whether these processes create a distinctive topography."


"Precipitation is a fundamental driver of erosional processes and exerts a strong control on ecosystem distributions, suggesting that these precipitation patterns may be important in understanding mountain geomorphology."
http://serc.carleton.edu/NAGTWorkshops/geomorph/vignettes/25201.html


Notes: Ponderosa and alligator juniper and pinon, but where are the shrubs, the Ceanothus, the mountain mahogany, the apache plume, the Ribes, not to mention all the riparian sumac, grape, hibiscus, false indigo, etc?

the north facing slopes are steeper and rockier, the south facing have a rock-flour consistency, less vegetated, less lichen on rocks...indicating more erosion, less life

Observations of soil erosion and retention in a Colorado Pinon/Juniper woodland

watch where you step
moss grows on the ground, sheltered by the slim shadow of this dead juniper
Marked keypoint (this is where sediment slows down), breakpoint, and contour line in this micro-drainage. The primary force structuring this topography is erosion, but the plants are not pedistalled. The slope is 1-2%.

Rio Puerco: the Poster Child of Eroded Watersheds

[NOTICE - This Road Not Maintained by New Mexico State Highway Department]

* Frederick Jacson Turner, father of modern American history, wrote persuasively that the frontier (where less than 3 people lived per square mile) defined American life, but that it closed in the 1890's as the country filled up with emigrants and settlers. But the land is emptying out again, as chronicled in Richard Manning's Grassland. The old world ecology and thinking brought by the Anglo settlers is failing in the drylands of the American West and the people are leaving, the roads abandoned. Despite massive government subsidies, the remaining ranchers and farmers have less and less to stand on every year. Populations in most rural counties peaked in the early 1900's and have declined ever since. The exodus that started with the dust bowl has continued unabated, as has the soil erosion and ecological damage.
[Could this be restored to its original ecology of cottonwood/willow bosque and gallery forest?]

Now, The Good News: "This is a search for the unknown...Now the sun is here, and he simply watches the land year by year to see what happens, waiting for the next clues as to what the nature of this place might be...It's like a ratchet in that we take the first turn, then back off and let nature take a turn, as we listen and watch as closely as possible, knowing that we are not so much rebuilding nature in these places as nature is rebuilding us. With each turn of this ratchet, nature reveals a bit more of itself to our science."
[SUN]

"In some real ways, the effort to re-find the landscape, which is the same as the effort to re-attach our lives to the land, is a religious quest, and it makes sense to consider it that way.

[Erosion (so bad it took 2 photos to fit): The bridge on the left used to span the river chanel. This is why the road is closed. Nature fights back. ]

"...it is difficult to imagine what we have learned. Annual topsoil loss to erosion here in some years totals one hundred tons per acre, or an inch of topsoil removed every 1.6 years...the topsoil the grass had built was thought to be so deep as to be inexhaustible..." p.165 from Grassland, Richard Manning.
[Dead willow, killed incidentally with herbicide "friendly fire"]

Mutilated and mutated willows, the taste of heavy metals on the tongue: this place has been sprayed. "Many in federal agencies ignore the connection between livestock grazing and weed invasions. Since they deny the role of livestock grazing, they seldom reduce the number of livestock allowed to graze public lands, even in areas where weeds are a major problem. Agency personnel prefer using herbicides and biocontrol agents to eradicate the weeds rather than trying to prevent the invasion of weeds in the first place." From "Comrades in Harm: Livestock and Exotic Weeds in the Intermountain West", Joy Belsky and Jonathan L Gelbard. in Welfare Ranching, Earth Island Press
[Rio Puerco Watershed: this area could be a State]
John Wesley Powell recommended that states and counties' boundaries in the American West be demarcated based on watersheds, since water is the natural form that power takes on the land...today, as witnesses of the modern West's "Water Wars" can attest, more and more political boundaries are being created or determined by water rights.

The Rio Puerco is oft mentioned as an example par excelance of some of the worst erosion in the United States. Once the "Breadbasket of New Mexico", the Rio Puerco watershed is now given as a common example of the degradation that can befall such formerly productive areas through mismanagement and ecological ignorance. Enhanced rates of erosion on the "dirty river" are the cause and effect of downcutting in the soft alluvium that formerly supported such bountiful harvests. Unstoppable headcuts and devegetated banks, combined with a climate shift that creates more "flashy" events (which, of course, are also caused by devegated uplands that lack competence and capacity to absorb rainfall, leading to sheetflow and immediate runoff that feed back to cause even more erosion...
[Landslide]
The Rio Puerco Management Committee lists several causes of erosion, such as (over) grazing and the placement of the new highway. As you can see from this photo essay, the war between the road and the river is not over yet. However, much of the battle has already been lost, and the country abandoned without roads. The downstream is reachable only by unimproved dirt roads and crosses some of the remotest parts of the state.
[Fenceline showing effects of grazing, on the right, where thickets of sagebrush dominate]

On the Importance of Meandering

Streams love to meander for reasons that are simple to understand yet profound to ponder. When a stream meanders around a bend the outside water must travel faster than the water on the inside of the curve. This increased speed leads to increased erosion and the bend becomes wider. As the bends become wider the overall length of the stream increases. Also, because the stream is eroding the landform more evenly, the overall grade is reduced and the water slows down. This decreased speed combined with increased length vastly alters the hydrological characteristics of the watershed, contributing to aquifer replenishment and filtering.

Changes in the Mississippi river's meanders:Meanders are a good thing that happen naturally. Sometime humans want to help the process along, especially for streams that have downcut and linearized (straightened). Water has momentum and will bounce off an oblique line of in-stream rocks, known as a vane, toward the opposite bank, starting an oscillation that can become a full-fledged meander.
Vane closeup showing rocks, stabalizing posts, and planted willow:
Several parallel vanes create an induced meander:
The banks that form behind vanes are first accretions of large boulders, then smaller rocks, and then small particles, all stacked somewhat like oranges at the supermarket. Because of the gradient of particle dimension, these banks act to soak up moisture from the stream through capillary action and are therefore great places to plant trees.
The old channel can still be seen seeping out from under the bank on the right while the new induced meander flows around to the left.:
Another view of the old channel seep (now on the left) and the new channel (on the right) flowing into a pond:
A dam can create ponding, which also slows water. The ratio of riffles to still water is an important measure of hydrological health, and for streams of this size and location the ratio should be close to 1:1. Even large rivers should often have this ratio; for example, the Columbia river, before it was artificially dammed and its watershed logged, held vast log jams stretching from bank to bank creating huge lakes. The easiest and most natural way to create ponding is with beavers, a keystone species that create habitat for hundreds of other species.

Unfortunately, there is not enough vegetation to support a beaver colony on Las Huertas. Creating an artificial pond with a wicker weir backed by an infill dam is a good short-term solution.
Eventually the dam will fill in with sediment, raising the stream bed and creating good streamside habitat. At present the pond helps raise the water table as well as store surface and subsurface water. The weight of the water in the pond pushes water further into the alluvium around the dam, supporting our revegetation project. Eventually there will be enough trees to support beavers and a self-sustaining ecological-hydrological system.

Another way to create ponding (and slow water) is a Zuni Bowl, an in-stream depression lined with rocks. It is named in honor of the Pueblo Indians in the Southwest who invented many of these water-control structures hundreds of years ago.
Slowing water is one way of slowing erosion. Another is stabilizing slopes.

The slope pictured below is divided into two regimes. The lower pitch is an equilibrium arrangements of small particles. This slope is also known as the angle-of-repose. The upper pitch is a nearly vertical cliff where disturbances can cause catestrophic failures.
The slope pictured below is composed of alternating regimes of angle-of-repose and cliffs. The slope erodes from the bottom and then unstable slopes just above that collapse, and so on. The progression of erosion from bottom to top is an example of effects moving "upstream": erosion at the mouth of the river affect the headwaters even though water only flows downstream. Even though stones can only roll downhill, their downhill absence propagates uphill to affect the perch of still-higher stones. Thus , what happens in a valley can determine the shape and slope of the mountains around it. By slowing erosion here we determine the shape of mountains.

A plant's roots can often form a barrier to the progression of erosion by holding together soil in a steeper slope. However, unless the root causes of erosion are addressed (e.g. with vanes) eventually soil will be washed away from the roots and/or the entire plant will be undercut.
A combination of engineered solutions and revegetation can work together synergistically to slow erosion. Indeed, since water velocity is determined by slope, decreased erosion is itself responsible for slowing water and hence slowing further erosion. The key to influencing such feedback systems is knowing where to interfere. Often restorationists find themselves faced with the bemusing problem of wanting to work simultaneously both downstream and upstream of the target stretch, asking themselves the question, "does the water above push the water below or does the water below pull the water above"?