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Splash erosion
♤ Splash erosion is the first stage of the erosion process.
It occurs when raindrops hit bare soil. The explosive impact breaks up soil aggregates so that individual soil particles are ‘splashed’ onto the soil surface.
Sheet erosion
♤ Sheet erosion refers to the uniform movement of a thin layer of soil across an expanse of land devoid of vegetative cover. Raindrops detach soil particles, which go into solution as runoff occurs and are transported downstream to a point of deposition.
Rill erosion
♤ When sheet flows begin to concentrate on the land surface, rill erosion occurs. While sheet erosion is generally invisible, rill erosion leaves visible scouring on the landscape. This type of erosion occurs when the duration or intensity of rain increases and runoff volumes accelerate.
Do you know?
The Satkosia Wildlife Sanctuary has witnessed an increase in crocodile population with about 123 gharials and muggers found inhabiting the Mahanadi river gorge.
Gully erosion
♤ Rill erosion evolves into gully erosion as duration or intensity of rain continues to increase and runoff volumes continue to accelerate. A gully is generally defined as a scoured out area that is not crossable with tillage or grading equipment.
♤ Ammonification: Production of ammonia as a result of the biological decomposition of organic nitrogen compounds.
♤ Border cropping: is growing of crops on the border areas of the plot or field
♤ Ex; Safflower as border crop in potato
♤ Border strip irrigation: It is an efficient method of irrigation close growing crops. In this method the field is divided by low flat levels into series of strips, each of which is flooded separately.
♤ Allelopathy: is defined as direct or indirect harmful effect of one plant over the other crop species through the exudation of toxic substances from the roots or the decomposition of crop residues
♤ C:N ratio: The ratio of the weight of organic C to the weight of total N in the soil.
♤ Check basin: It is a method of irrigation with beds and channel for retaining water to form a pond
♤ Heaving: Injury to plants caused by lifting upward of the plant along with soil from it’s normal position in
temperate regions where snowfall is common
♤ Contour farming: is the farming practice of ploughing across a slope following its elevation contour lines.
♤ Cover crops: crops which are grown to cover the soil in order to reduce the loss of the moisture from the soil due to leaching and erosion.
♤ Critical stage of irrigation: the period or the stage of development of lifecycle of the crop when it is most sensitive to moisture stress, results in yield loss
♤ Hard pan: It is a hard and impermeable layer formed in the soil profile by accumulation of materials such as salts, clay etc which impedes drainage
♤ Growth regulators: Organic substances which in minute amount may participate in the control of growth processes Ex:Auxins, Cytokinins
♤ Heliophytes: Plants of sun loving species, require intense light for normal development Ex: Rice, Wheat, Cotton, Sugarcane
♤ Sciophytes: Plants which are shade loving and require less light intensity
♤ Heliotropism: It is the movement of the plant parts towards the sun Ex: Sunflower
♤ Geotropism: A growth movement in response to gravity. Eg Groundnut peg penetration into the soil
♤ Herbicide: A chemical used for killing or inhibiting the growth of unwanted plants Ex: Atrazine
♤ Insecticide: It is the chemical used for killing the insects: Endosulfan
♤ Hidden hunger: Is the condition where plants do not exhibit visual symptoms of deficiency for the short supply of particular nutrients but will result in yield losses
♤ Humus: A brown or black organic substance consisting of partially or wholly decayed vegetable or animal matter that provides nutrients for plants and increases the ability of soil to retain water
♤ Mulching: Practice of covering the soil surface with materials like plant residues, straw, leaves or plastic film to reduce evaporation, restrict weed growth and maintain the soil temperature
♤ Puddling: It is the ploughing operation carried out in stagnated water conditions to create an impervious layer below the plough pan
♤ Shifting cultivation: It is the old practice of cutting and clearing of forest for cultivating crops for a certain period of time as long as the soils having fertility
♤ Subsidiary farming: Settled Farming in river banks and streams in addition to gathering & hunting
♤ Subsistence farming: Raising the crops only for family needs and not for commercial: “Grow it and eat it”