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Emerging in North America in the 1970s and 1980s, vertical tillage (VT) is a system of principles and guidelines similar to conservation agriculture (CA) in that it aims to improve soil health, increase water infiltration and decrease soil erosion and compaction (improve bulk density). With varying degrees of soil movement, it aims to not invert the soil and keep residue on the surface where it protects the soil. [1] It usually includes small forward-facing discs that limit soil inversion and slices the residue for faster decomposition and to get a seeder or planter into the heavy residue-laden fields. Many times it also includes a deep ripping tool for breaking up hard pans and compaction created from traditional tillage implements and heavy equipment like large tractors and combine harvesters.
Benefits include:
Its proponents[ who? ] compare it and even include it into no-till and conservation agriculture categories. They claim that VT has helped particularly in the build-up of high levels of residues on the surface under zero-till and CA systems and the concomitant low soil temperatures and compaction problems have hindered crop establishment and growth in the temperate regions of North America. Its detractors[ who? ] may concede the above advantages but claim the vigorous soil movement excludes it from no-till and CA categories. [2] This is important particularly in the United States, where it may exclude farmers in collection of direct farm payments from the US government that aims to promote no-till to conserve soil and keep it in place.
Besides this controversy, there is considerable variation in the definition of what constitutes VT, even among its proponents. [3]
Tillage is the agricultural preparation of soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shoveling, picking, mattock work, hoeing, and raking. Examples of draft-animal-powered or mechanized work include ploughing, rototilling, rolling with cultipackers or other rollers, harrowing, and cultivating with cultivator shanks (teeth).
Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. This practice reduces the reliance of crops on one set of nutrients, pest and weed pressure, along with the probability of developing resistant pests and weeds.
Soil erosion is the denudation or wearing away of the upper layer of soil. It is a form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, and animals. In accordance with these agents, erosion is sometimes divided into water erosion, glacial erosion, snow erosion, wind (aeolean) erosion, zoogenic erosion and anthropogenic erosion such as tillage erosion. Soil erosion may be a slow process that continues relatively unnoticed, or it may occur at an alarming rate causing a serious loss of topsoil. The loss of soil from farmland may be reflected in reduced crop production potential, lower surface water quality and damaged drainage networks. Soil erosion could also cause sinkholes.
Conservation agriculture (CA) can be defined by a statement given by the Food and Agriculture Organization of the United Nations as "Conservation Agriculture (CA) is a farming system that can prevent losses of arable land while regenerating degraded lands.It promotes minimum soil disturbance, maintenance of a permanent soil cover, and diversification of plant species. It enhances biodiversity and natural biological processes above and below the ground surface, which contribute to increased water and nutrient use efficiency and to improved and sustained crop production."
In geotechnical engineering, soil structure describes the arrangement of the solid parts of the soil and of the pore space located between them. It is determined by how individual soil granules clump, bind together, and aggregate, resulting in the arrangement of soil pores between them. Soil has a major influence on water and air movement, biological activity, root growth and seedling emergence. There are several different types of soil structure. It is inherently a dynamic and complex system that is affected by different factors.
Topsoil is the upper layer of soil. It has the highest concentration of organic matter and microorganisms and is where most of the Earth's biological soil activity occurs.
No-till farming is an agricultural technique for growing crops or pasture without disturbing the soil through tillage. No-till farming decreases the amount of soil erosion tillage causes in certain soils, especially in sandy and dry soils on sloping terrain. Other possible benefits include an increase in the amount of water that infiltrates into the soil, soil retention of organic matter, and nutrient cycling. These methods may increase the amount and variety of life in and on the soil. While conventional no-tillage systems use herbicides to control weeds, organic systems use a combination of strategies, such as planting cover crops as mulch to suppress weeds.
Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place of nutrient application.
Tilth is a physical condition of soil, especially in relation to its suitability for planting or growing a crop. Factors that determine tilth include the formation and stability of aggregated soil particles, moisture content, degree of aeration, soil biota, rate of water infiltration and drainage. Tilth can change rapidly, depending on environmental factors such as changes in moisture, tillage and soil amendments. The objective of tillage is to improve tilth, thereby increasing crop production; in the long term, however, conventional tillage, especially plowing, often has the opposite effect, causing the soil carbon sponge to oxidize, break down and become compacted.
Soil conservation is the prevention of loss of the topmost layer of the soil from erosion or prevention of reduced fertility caused by over usage, acidification, salinization or other chemical soil contamination.
Crop residues are waste materials generated by agriculture. The two types are:
Strip-till is a conservation system that uses a minimum tillage. It combines the soil drying and warming benefits of conventional tillage with the soil-protecting advantages of no-till by disturbing only the portion of the soil that is to contain the seed row. This type of tillage is performed with special equipment and can require the farmer to make multiple trips, depending on the strip-till implement used, and field conditions. Each row that has been strip-tilled is usually about eight to ten inches wide.
A disc harrow is a harrow whose cutting edges are a row of concave metal discs, which may be scalloped or set at an oblique angle. It is an agricultural implement that is used to till the soil where crops are to be planted. It is also used to chop up unwanted weeds or crop residue.
The term cropping system refers to the crops, crop sequences and management techniques used on a particular agricultural field over a period of years. It includes all spatial and temporal aspects of managing an agricultural system. Historically, cropping systems have been designed to maximise yield, but modern agriculture is increasingly concerned with promoting environmental sustainability in cropping systems.
Soil management is the application of operations, practices, and treatments to protect soil and enhance its performance. It includes soil conservation, soil amendment, and optimal soil health. In agriculture, some amount of soil management is needed both in nonorganic and organic types to prevent agricultural land from becoming poorly productive over decades. Organic farming in particular emphasizes optimal soil management, because it uses soil health as the exclusive or nearly exclusive source of its fertilization and pest control.
Controlled traffic farming (CTF) is a management tool which is used to reduce the damage to soils caused by heavy or repeated agricultural machinery passes on the land. This damage and its negative consequences have been well documented and include increased fuel use, poor seedbeds, reduced crop yields and poor soil function in terms of water infiltration, drainage and greenhouse gas mitigation due to soil compaction.
Regenerative agriculture is a conservation and rehabilitation approach to food and farming systems. It focuses on topsoil regeneration, increasing biodiversity, improving the water cycle, enhancing ecosystem services, supporting biosequestration, increasing resilience to climate change, and strengthening the health and vitality of farm soil.
Soil compaction, also known as soil structure degradation, is the increase of bulk density or decrease in porosity of soil due to externally or internally applied loads. Compaction can adversely affect nearly all physical, chemical and biological properties and functions of soil. Together with soil erosion, it is regarded as the "costliest and most serious environmental problem caused by conventional agriculture."
This glossary of agriculture is a list of definitions of terms and concepts used in agriculture, its sub-disciplines, and related fields. For other glossaries relevant to agricultural science, see Glossary of biology, Glossary of ecology, Glossary of environmental science, and Glossary of botanical terms.
Tillage erosion is a form of soil erosion occurring in cultivated fields due to the movement of soil by tillage. There is growing evidence that tillage erosion is a major soil erosion process in agricultural lands, surpassing water and wind erosion in many fields all around the world, especially on sloping and hilly lands A signature spatial pattern of soil erosion shown in many water erosion handbooks and pamphlets, the eroded hilltops, is actually caused by tillage erosion as water erosion mainly causes soil losses in the midslope and lowerslope segments of a slope, not the hilltops. Tillage erosion results in soil degradation, which can lead to significant reduction in crop yield and, therefore, economic losses for the farm.
Just one pass with a vertical tillage tool can improve planting conditions while still maintaining surface residue. However, aggressive use of the tools, or using it on more than one pass, will decrease the conservation benefits