Sandy Beaches and Dunes

What comes to mind when you hear the phrase, “Sands of time?”

An hour glass?… video game?… song title?… book?…

The photo-circles above clearly show “sand.” We find it on beaches everywhere and easily recognize it as tiny-tiny particles of pulverized rock and mineral. We’re happy when we get to the beach, and promptly begin to enjoy sand-related activities; not really giving sand much of a second thought. But a healthy helping of  “second thought” is what sand deserves. It is fascinating. And so are the physical and biological systems that rely on sand.

 Here is where a new spin on the   sands of time  gets underway…

With two questions:

– What is sand?

– Where does sand come from?

The sand on Oregon beaches formed as rock was broken down through weathering and erosion into sedimentary particles between 0.0625 (1/16) mm and 2mm in diameter.This process occurred during the late Pleistocene(11,700BP) and Mid-Holocene (6,000BP) in rivers that washed these particles to the ocean where they have been carried by tides and winds along the coastline to form sandy beaches and dunes. In this sense, we walk along the sands of time each time we visit the beach. These old sands, or relic sands, are a mix from four source sites:

1. Columbia River (Igneous- Mineralogy: Hypersthene and Augite)
2. Coast Range (Ingneous- Mineralogy: Augite and Hornblend)
3. Umpqua River (Igneous and Metamorphic- Mineralogy: Augite, Hornblend, Hypersthene, and Garnet)
4. Klamath Mountains of Southern Oregon and Northern California (Igneous and Metamorphic- Mineralogy: Augite and Garnet) (Lonsdale)

Time in the Hatfield Marine Science lab gave us the opportunity to examine sand structure with microscopes. The mineral blend and roundness/sphericity provided clues to the age of the sands of time. Older sands were more rounded; more recent sand particles were more angular.

Why is sand so important?

I think it is safe to say that sand is the foundation  for life in the sandy beach-dune ecoregion. Without sand… organisms from microscopic to the very largest  would perish.  The food web begins with the microscopic organisms that live between the grains of sand. When we take walks along intertidal zones, we are literally walking on the backs of the meiofauna community of organisms that reside there… about a million of these microbial creatures can be found in just a square meter of beach. If we consider sandy beaches account for about 72% of Oregon’s coastline… that’s a lot of inhabitants!

The Hatfield Science Lab provided an opportunity to view  some of the microscopic  between-sand-particle dwellers.I did not have the ability to take photographs of the meiofauna we viewed during our microscope studies. However, the above video provides an informative and entertaining look at the organisms that live between the grains of sand. Watch to view living examples of meiofauna and to learn more about them. It’s well worth the time!

David also set up a display of preserved specimens to give us some ideas  about what to look for once we were out on the beach and in the dunes. Click to view as a slideshow and the labels will be easier to read:

The Museum of Sandy Beaches & Dunes

Beach Pea (Lathyrus japonicus) – usually found in sand. Pods believed to have medicinal value

Pacific Silverweed (Potentilla anserina ssp. pacifica)- wet spots and sandy spots usually near the sea. Native peoples ate the roots, and used them also for medicinal purposes.

Salt Rush

European Beach Grass (Ammophila arenoria) and American Dune Grass (Elymus mollis)

Seashore Lupine (Lupinus littoralis)- sandy beaches and dunes. Native peoples peeled roots, roasted them, and ate with oolichan grease. Eating lupine involves knowing what you are doing as some contain toxic alkaloids and should be considered poisonous.

Slough Sedge (Carex obnupta)- marshes, swamps, bogs, stream-banks. Popular basket-weaving material- often with cedar foundations and intricate designs from dyed strands of grass or colored barks.

Coastal Strawberry (Fragaria chiloensis)- common on sand dunes and sea bluffs. Native peoples ate berries; used leaves for tea; chewed leaves were used a poultice on burns; leaves also used for anti-diarrhea medicines.

Various beach flora

Mole Crabs

Beach Bloodworm

Smooth Bay Shrimp

Various bivalves

We don’t know what this is!

Newport Littoral Cell- South Beach State Park- Newport, Oregon

After lunch, we proceeded to South Beach State Park.  The sandy beaches and dunes we explored are located in the Newport Cell, a littoral cell that is twenty-seven miles long; between Yaquina Head and Cape Perpetua. Sand movement in the area where we worked is impacted by beach stabilization projects and the Yaquina Bay jetty system. Shoreline topography is dramatically, and largely irreversibly, affected by these anthropogenic impacts on the once dynamic seasonal and landform-related sand dune movements driven by wind and tide patterns. Of the two human-made disturbances, beach stabilization is the most profound. The introduction of European Beach grass has been so successful in preventing natural sand shifting that Oregon’s dunes are actually disappearing. Some experts predict much of our state’s wild dune system will be gone within the next 50-100 years. “European Beach grass on the foredunes permanently (minimizes) sand movement, thereby trapping all windblown sand at the foredune and thus starving inland areas from the formation of the larger dune features,.”(Lonsdale)

In the next sections of this entry, I will use the “Field Trip Workbook and Field Diary” as a guide. David gave us this tool to record our Naturalist activities and observations. Unfortunately- wind, rain, and time constraints of the day prevented us from the benefit of using it to its fullest potential on site.

Dune Observations-

After breaking into teams, we drove to South Beach. Prior to beach entry we reviewed Oregon Parks Department signage. A trek through dunes allowed an initial observation opportunity to identify dune features. A second dune walk later in the day provided another occasion to make observations.This set of photos is a record of my observations during both walking tours of dune areas on March 15, 2015. Notes are written in the caption area for each photograph. Clicking on a photo to view as a slideshow makes reading of notations easier. I have attempted to label correctly, however, if errors have been made- I would appreciate feedback in the comments area below this post. Then I can make the corrections.  Thank you in advance 🙂

Credit: USDA Forest Service

Oregon State Park Beach Regulations and Information

Dune-back Sandy Shore Foredunes as viewed from beach

Hummocks behind foredunes. Mounds of sand piled in and around vegetation. Height: 1-several meters Generally unstable; eventually erode away.(Weidemann)

Sand Plain. Flat to undulating sand surface. If extensive, may have transverse ridge pattern present. May be partially or completely vegetated. Not wet. (Weidemann)

Example of a Blow Out area. Saucer or trough-shaped erosional depression in established vegetation. Vary widely in size. (Weidemann)

Dune Ridge. Ridge remnants of other dune forms that have been completely stabilized by vegetation. (Weidemann) Pictured here- small plant: American Beach Grass. Denser, larger plant: European Beach Grass.

Beach, looking toward surf at high tide.

Deflation plain- flat sand surface formed by erosion of sand to the table. Standing water during the rainy season. Quickly vegetated. (Weidemann)

Deflation plain- flat sand surface formed by erosion of sand to the table. Standing water during the rainy season. Quickly vegetated. (Weidemann)

Deflation plain- flat sand surface formed by erosion of sand to the table. Standing water during the rainy season. Quickly vegetated. (Weidemann)

Tree island. Floating in the sand, these islands are small isolated remnants of older coastal forests that were almost completely buried by sand. The islands are proof that moving sand is capable of burying whatever is in its way. Steep slopes make the tree islands unstable and susceptible to erosion.

Tree island. Floating in the sand, these islands are small isolated remnants of older coastal forests that were almost completely buried by sand. The islands are proof that moving sand is capable of burying whatever is in its way. Steep slopes make the tree islands unstable and susceptible to erosion.

Looking down from sand dune- encased Spruce tree gives an idea for how deeply buried by sand the old-growth tree is. Once again, this makes me wonder about “the sands of time.”

Transect to Assess Distribution and Abundance of South Beach Macrofauna

Step 1- Abiotic Profile

Recently, I noticed that NASA lists the “Vital Signs of the Planet” on its Global Climate Change website (link is at the bottom of my blog). Over time, this abiotic data will assist scientists to educate the public on the patterns that confirm global change. As a Master Naturalist, knowing what data to collect and how to collect it is a timely and valuable skill.  The next set of photographs record the collection of data.

Site Location: South Beach State Park, South Jetty (Newport, Oregon)

Date: March 15, 2014       Time Profile Developed: 1300           Profile Location: Surf zone- Sandy Beach

Weather:  Mist                     % Cloud Cover:  100%                             Air Temperature:  54 F;  17 C

Type of Substrate:  100% fine sand; some debris                           Tidal Information:  12:18 was high tide

 Sea Conditions:  Small surf with larger swells

Sea Conditions: Small surf with larger swells

Dissolved O2 Concentration (ppm): 7

Dissolved O2

Dissolved O2

Dissolved O2

Dissolved O2

Dissolved O2- checking for a match on scale

Concentration level Dissolved O2 = 7ppm

pH:  7.5

ph Measurement

Locating pH number on scale = 7.5

Salinity (0/00):  30.9                       Water Temperature:  16.7 C

Salinity

Water Temperature = 16.7C

Salinity = 30.9

Wind Speed:  Steady Wind   15mph   12-16 knots

Wind Speed 15 mph 12-16 knots

Wind Speed Beaufort Scale

Wind Speed

Step 2:  Transect Teams Assess Distribution and Abundance of macrofauna

At the surf zone, nets were used to sweep along the bottom back and forth digging the rim shallowly into the sand. Then we examined for biota by dumping the catch into a several inches of water in a bucket.

David modeled the process of setting up our data collection sites along lines of transect. Starting at the swash zone we measured 100 feet eastward toward the last high tide strand line. Zero feet was station one where the first set of four holes were dug and assessed for biota. This process continued every 10 feet up the transect line.

We’re off to do transection!

Photo credit: Shirlee Benell

Weather Conditions- fine mist, 54degrees with light wind

Beginning of transect site set up- measure off 100 feet starting at swash line.

Transect end point- 100 feet east, towards last high tide line.

Staking the end point of transection.

Demonstration of hole-sample procedure. Four holes per dig site, down to water table.

Photo Credit: Shirlee Benell. Hand-held science equipment- magnification chamber

Transect in progress! Notice wave action on Yaquina Bay Jetty in the background. This Jetty impacts the sand movement and dune dynamics on this beach.

Transect data collection at various points on a transection site.

Transect hole digging

Search of biota in the sand. One sand flea was found.

Surf line biota collection was the most productive sample site of our transection results.

amphipods Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from 1 to 340 millimetres (0.039 to 13 in) and are mostly detritivores or scavengers. (wikipedia)

Amphipod

Amphipod

Jelly fish

California Amphipod

Mole Crab

Mole crab- posterior

two mole crabs, one amphipod

Amorous amphipods

mole crabs/amphipod

Still don’t know what this is!

fossil clams

Macroflora (and one insect) Observed during Dunes Walking Tour

beetle

1-?-Sedum integrifolium

Beach Pea

Tansy Ragwort (Senecio jacobaea) in the rosette stage– it’s a noxious/invasive weed in Oregon (kills livestock)

Beach Lupine

Beach Lupine

Common mullein (Verbascum tahapsus L.) – also an noxious weed, very invasive (introduced from Europe in the 1700’s)

Coastal Strawberry

Leathery polypody (Polypodium Scouleri), unfortunately the ones that grow at the beach don’t taste of licorice like their inland Licorice Fern (Polypodium glycerhizza) cousins do.

Evergreen Huckleberry

Evergreen Huckleberry

Pacific Crabapple

Pacific Crabapple

Pacific Crabapple

Coastal Juniper

Shore Pine (Pinus contorta)

Slough Sedge

Orchid- Western Rattlesnake Plantain (Goodyera oblongifolia)

Orchid- Western Rattlesnake Plantain (Goodyera oblongifolia)

Sands of Time – Tides of Change

The experiences of this field trip …anchored in the sands of time… those of distant and present times … impacted my activities on this particular day. What will happen in these dunes, and others along the Oregon coastline, is waiting to be told as dynamic earth events and  anthropogenic activities merge.Learning to pay attention, to use data wisely, and to make informed decisions in how we choose to manage- or not manage- natural resources seems more important now than ever.

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