The Creation Of Sand Dunes
There are five main steps to the creation of sand dunes:
A strong sea breeze which is blowing inland will pick up the sand
grains and move them on to the beach. This happens when the tide goes
out and the sand on the beach dries. The sand grain will carry on
moving with the wind and will not stop until there is something in
their way. At the top of the beach there is a usually a strand line.
This consists of seaweed and litter left by the tide. The sand grains
jump over this strand line and collect where the calm air is behind
it. This creates a small embryo dune. The dune can easily be destroyed
unless it is colonised by plants. Sea couch grass is the most common
plant that can grow on salty dry sand.
The sand is then bind together with the help of the long spreading
roots of the sea couch grass. The dune will grow as more and more sand
is trapped. Marram grass will then colonise the dune and replace the
sea couch grass once the dune is about a metre high. It is
unproblematic for the marram grass to obtain water as its long roots
are fifteen to twenty metres long. This becomes a super sand trap and
dunes covered with marram can grow in height by a metre a year. A dune
which is ten to twenty metres high is called a yellow dune, and there
is a possibility a new embryo dune may form in front of it.
Conditions at the back of the dune become less windy and less sand
builds up instantaneously behind it once the yellow dune is about ten
metres high. When marram grass dies, it decays on the dune adding
humus to the sand. The humus and sand combination forms a soil in
which other plants are able to grow. These may include dandelions and
restharrow. This type of dune is called a semi-fixed dune.
The soil depth increases as time goes by time and the soil also
coast (as shown in pictures 1 & 2). The area of sea is subject to the
There are many different types of coasts that exist throughout the United States. The south shore of Long Island has a unique types of coast known as a barrier beach. Barrier beaches are long narrow land forms that are composed of sand and other lose sediments. These sediments are brought together by the actions of waves, currents and storm surges. Barrier beaches are subject to constant changes by the same forces. Sand is constantly eroded in one area an deposited in another. Barrier coasts are important for a number of reasons; they protect the mainland of Long Island from the open ocean and flooding during storms, for recreational use and the unique ecosystems which exist on barrier beaches.
Desert Solitaire aims to draw attention to the activities of a man voluntarily isolated in nature. It seeks to identify the strife that Abbey faces with modern day human’s treatment of his nature. As such, the argument that Abbey poses in one his earlier chapters Rocks is, that the Modern Day man is destructive and cannot be trusted to preserve nature as is.
The American Dream has been a fantasy for many people around the world. It has
Firstly, we need to gain a general understanding of the structure and functions of the salt marshes in Jamaica Bay. Salt marshes are most commonly manifested through the arrival of seeding’s of the cord grass known as Spartina alterniflora. The grass spreads asexually through the aquatic habitats beneath the earths’ surface. The grass becomes...
Desert pavements are common landforms in arid regions. They consist of flat or sloping surfaces where stones are closely packed angular or rounded, and generally exhibit low relief (Mabbutt, 1977). Pavements tend to form on both alluvial fan toposequences and on weathering volcanic flow fields in arid regions. Soils are often found under desert pavements and they play an important role in the evolution of pavements (McFadden et. al., 1987). In the past there have been several theories as to the formation pavements and soil development beneath them. Deflation, or the erosion of finer grained particles from a surface, stone concentration by wash erosion and upward displacement of stone due to shrink and swell clay characteristics were at one time believed to be the main factors in the formation of desert pavements (Mabbutt, 1977). However, more recent research has shown that desert pavements are born and maintained at the surface, and that the soil below them is mainly eolian in origin. Slow accretion of eolian dust below the pavement is a process that eventually develops cumulate horizons. Eolian dust in environments where pavements often develop is rich in carbonate salts and clays due to the fact it often originates from nearby playa lake evaporate basins (McFadden et. al., 1987). Soils that form below the pavements over time develop calcic horizons and clay rich structure due to the influx of these eolian fines through the pavement surface. In turn the development of mature or plugged calcic horizons effects the form of the pavement surface because it alters the water drainage infiltration rate and causes pavements to decline.
The critical thinking assignment for this week entails two questions, describe the hydrologic cycle and apply it to where I live, and secondly choose a landscape either glacial or desert and describe how it forms, as well as the landscape features found on it. I will use this essay to answer both questions. I will be using my hometown of Napa California to answer the first question and I have selected the Mojave Desert landscape to answer the second question.
Surfers, swimmers and sunbathers use beaches for recreation. People fish off beaches for food. Since many people take their vacations at the beach, lots of beaches in tropical locations are important to their country’s economy. Entire cities, regions and countries depend on the money tourists spend while visiting the beach. Beaches are naturally very dynamic places, but people try to control them and build permanent structures, such as houses, restaurants, shops and hotels, on or near the shore. The natural erosion and deposition of beaches becomes a problem. Beaches con disappear over time, or even over night during severe storms. Beaches are areas of loose sediment (sand, gravel, cobbles) controlled by ocean processes. Most beaches have several characteristic features. First are offshore bars, which help protect beaches from erosion. Next is the foreshore, which rises from the water toward the crest of the next feature; a berm. On low-lying shores, dunes form behind beaches. Dunes look like rolling hills of sand and are blown into place by the wind. New, smaller dunes are often changing shape as the wind continues to affect them. Waves and currents move the accumulated sediment constantly creating, eroding and changing the coastlines.
Abiotic factors are things that are nonliving that influence an environment and it's inhabitants. Some of the abiotic factors that are attributed to coastal erosion in Louisiana are hurricanes, tropical storms, elevation, sunlight, overnutrition, sea-level rise, and deposition. Hurricanes bring about larger waves which cause dune erosion or beach erosion (Clark et al., 1998). This is significant because beaches and/or the dunes of the beach serve as buffers to the coastline and the ecosystem. As the beach or dunes recede from the erosion caused by these large waves and an increased sea-level the flora and fauna that help sustain the area die off or retreat to a more habitable zone leaving the wetlands in a critical state often resulting in a total loss of the area (Stockdon et al., 2012). Due to the nature of the Gulf of Mexico large destructive storms such as hurricanes or tropica...
The Sandia Mountains named after a watermelon in Spanish because of the red light that shines over them in the evening. Located in Albuquerque, New Mexico, it’s great for an afternoon hike. We decide to drive to the mountains and arrived at around 2 pm.
As humans, we need food to survive. This is a basic need and want and has always been primarily done by farming the land. That farmed land requires sunlight, nutrients, and fresh water. If one of these three criteria is missing, the land is no longer able to birth vegetation. The biggest issue we face here in Canada is desertification. This term means that the land being classified with this is losing its water either to drought or to human causes. Desertification is a form of land degradation and is found to be an issue all over the globe. These dry lands are not just centered on a small percentage of people but affect up to half of the world’s population. This type of soil erosion is due to many factors. The biggest is the latitude of the area under concentration. Of course the closer you are to the equator the hotter and less precipitation is going to reach the land and this also affects natural weather cycles. The sad thing is however that where there is desertification, poverty will not be far. This makes sense for the reason we have poverty is because there are people without food and shelter. This connects to the lack of vegetation for with desertification the food and materials needed cannot grow to make a successful civilization. Looking at what causes desertification we can at least attempt to reverse the results. Desertification is caused by human error by globalizing prematurely.
Analysis of sites in five coastal states indicate that many marshes and mangrove ecosystems receive adequate mineral sediments to produce enough organic sediment and root material to remain above sea level at the present rate of sea-level rise (1-2 mm per year globally). However, three of the twelve wetlands studied were not keeping pace with the current rate of sea-level rise. If sea-level rise accelerates, some additional sites would also begin to slowly deteriorate and submerge.
Investigating the Effect of Drop Height on the Depth of Sand Aim: To investigate the depth of the sand depending on the height at which the ball is dropped from. Variables: Independent variable chosen: The height at which the ball is dropped Dependent variable chosen: The depth of the sand after removing the fallen ball from it. Constant variables and how they will be controlled: Variable How we will keep it constant Amount of sand We leave the sand in the bucket and make sure that none spills over. Type of sand Use the same one for each trials Ball Use the same ball for each trial, with the same size, volume, material and brand.
The Sand Cone Model describes business improvement as a process which should be based on improving specific competitive dimensions in a different order (Meredith & Shafer, 2013). For instance, a business which is struggling with quality outputs should place an emphasis on improving the quality of its outputs first. Businesses that produce high quality outputs are successful over the long term. Matthew 7:24-25 (ESV) states, “Everyone then who hears these words of mine and does them will be like a wise man who built his house on the rock. And the rain fell, and the floods came, and the winds blew and beat on that house, but it did not fall, because it had been founded on the rock.” When a business builds its foundation on
The Sahara's landscape features include shallow basins, large oasis depressions, gravel-covered plains, plateaus, and mountains, sand sheets, dunes and sand seas. Sand sheets and dunes cover over 25 percent of the Sahara’s surface. The most common types of dunes include tied dunes, blowout dunes, and transverse dunes. Within the Sahara are several pyramidal dunes that reach over 500 feet in height while others reach over 1,000 feet. Researchers have for many years tried to figure out how these dunes were formed, but the case remains unsolved.