What is soil erosion? Soil erosion is a natural process, occurring over geological time, and indeed it is a process that is essential for soil formation in the first place. With respect to soil degradation, most concerns about erosion are related to accelerated erosion, where the natural rate has been significantly increased mostly by human activity. Soil erosion by water is a widespread problem throughout Europe. Soil is naturally removed by the action of water or wind: such 'background' (or 'geological') soil erosion has been occurring for some 450 million years, since the first land plants formed the first soil. Even before this, natural processes moved loose rock, or regolith, off the Earth's surface, just as has happened Where it does so, the soil’s surface will be lowered slightly. Lowered areas form preferential flow paths for subsequent flow, and these flow paths are in turn eroded further. Eventually, this positive feedback results in small, well-defined linear concentrations of overland flow (‘microrills’ or ‘traces’). In many cases, individual microrills become ineffective over time due to sedimentation. A subset, however, grow further to become rills; and a smaller subset may go on to develop into gullies. This process of ‘competition’ between microrills and rills leads to the self-organized formation of networks of erosional channels (dendritic on natural soil surfaces; constrained by the direction of tillage on agricultural soils), which form efficient pathways for the removal of water from hillslopes. It is in such erosional channels that water erosion also operates most effectively to detach and remove soil by its kinetic energy. In most situations erosion by concentrated flow is the main agent of erosion by water. The flow-dominated erosional channels are separated by interrill areas where the dominant processes are rainsplash and diffuse overland flow; however, boundaries between rill and interrill areas are both ill-defined and constantly shifting.
[pic] Large rills (possibly big enough to be called gullies?) on an eroding hillslope.
In some circumstances subsurface flow may be important in determining where
Week 4 worksheet ENV/100 August 16, 2013 Tiffany Alvarez Week 4 worksheet How do minerals affect society? Minerals can affect society in many ways for example; Surface mining destroys vegetation across large areas, increasing erosion. Open-pit mining uses huge quantities of water. Acid mine drainage is pollution caused when dissolved toxic materials wash from mines into nearby lakes and streams. Minerals is approximately 80 percent of mined ore consists of impurities that become wastes after…
INTRODUCTION What is erosion, sediment and its courses in South Africa? Erosion: it’s the process of soil particle breaking down and Sediment it’s the soil that has moved from its original because of water movement speed or volume. Sometimes it can cause by the different temperatures between day and night. Sediments make the water appear brownish-grey; they are an indicator of increased water runoff, land degradation, erosion due to intensive industrialized land use, land sealing, and poor soil management…
on the coast, place demands and pressures on coastal systems. Acid sulphate soils are found in large areas of Australia’s coastal plainds, wetlands and mangroves. As the acid moves through the soil it releases other toxins that eventually flow into surrounding waterways. This decreases water quality and damages sensitive ecosystems. Common management strategies Sea walls are structures used to prevent coastal erosion. Breakwaters are stone structures built at the entrance of rivers to prevent…
EROSION CONSERVATION H. Allen Childress Everest University February 13, 2013 EROSION CONSERVATION There are three major causes of soil erosion Overcultivation, Overgrazing, and Deforestation. Each one of these environmental events have a major impact on our soils and how soils decline in nutrient value supporting our ecosystem. The good thing is that each of these causes of erosion can be corrected to create a more sustainable soil structure. Overcultivation is the practice of repeatedly…
effects of weathering and erosion. Each response must be at least 200 words. |Effects of Weathering |Effects of Erosion |What are the Differences? | |Weathering is the process of rock material |Erosion is when wind, water and ice |One difference between weathering and | |being broken up by air and water. One type |dislodge, dissolve or remove the materials |erosion is how humans can effect erosion | |is mechanical weathering…
and labor intensive than mechanical control Les energy inputs than mechanical control Advantages Generally cheaper than mechanical control Most herbicides are selective Especially detrimental to most forbs Generally maintains some degree of soil cover If applied correctly herbicide control is generally safe and reliable Can fit with other control methods into an integrated pest management plan Can be used good for thinning brush/trees Good for eradication of small stands of undesirable…
increase and population growth leads to degradation of ecological environment, such as soil erosion and natural habitat loss. Firstly, the main cause of soil erosion is deforestation for trade and farmland. Nowadays, in some less-developed countries, the living pressure increases with the numbers of population. These people have to cut down the trees for trade and use the land for farming. That may hide danger of soil danger in the future. According to Pakenham (2005), for example, in Nepal, the people…
Phosphate Cycle Reflection In this cycle, I found interesting that phosphate cycle’s starting point is from the mining and rock erosions. Also, while researching about phosphorus cycle, I learned that phosphorus was essential for plant growth. It was interesting how phosphate came from mining and also from dead decayed animals. When they go back to the soil, the cycle begins again. The phosphorus cycle occurs slower than any other biochemical cycles because the processes that move the phosphorus…
earth’s mountains. Active volcanic forces can also build mountains when lava from the volcanoes harden. As internal forces within the earth’s surface build landforms, external forces called weathering and erosion work to wear them away. Rock is constantly changing due to weathering and erosion. Weathering is the breakdown of rocks due to temperature changes, water and plant roots. The top layer…