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26-843: A crop is a plant grown and harvested for agricultural use. Crop may also refer to: CROP may also stand for: Crop When plants of the same species are cultivated in rows or other systematic arrangements, it is called crop field or crop cultivation. Most crops are harvested as food for humans or fodder for livestock . Important non-food crops include horticulture , floriculture , and industrial crops. Horticulture crops include plants used for other crops (e.g. fruit trees ). Floriculture crops include bedding plants, houseplants, flowering garden and pot plants, cut cultivated greens, and cut flowers . Industrial crops are produced for clothing ( fiber crops e.g. cotton ), biofuel ( energy crops , algae fuel ), or medicine ( medicinal plants ). The production of primary crops

52-461: A soil (and the fauna and flora associated to it) that took more than a 1000 years to build up. Soil regeneration is the reformation of degraded soil through biological, chemical, and or physical processes. When productivity declined in the low-clay soils of northern Thailand, farmers initially responded by adding organic matter from termite mounds , but this was unsustainable in the long-term. Scientists experimented with adding bentonite , one of

78-846: Is adding the most value. The importance of a crop varies greatly depending on the region. Globally, the following crops contribute most to human food supply (values of kcal/person/day for 2013 given in parentheses): rice (541 kcal), wheat (527 kcal), sugarcane and other sugar crops (200 kcal), maize (corn) (147 kcal), soybean oil (82 kcal), other vegetables (74 kcal), potatoes (64 kcal), palm oil (52 kcal), cassava (37 kcal), legume pulses (37 kcal), sunflower seed oil (35 kcal), rape and mustard oil (34 kcal), other fruits , (31 kcal), sorghum (28 kcal), millet (27 kcal), groundnuts (25 kcal), beans (23 kcal), sweet potatoes (22 kcal), bananas (21 kcal), various nuts (16 kcal), soybeans (14 kcal), cottonseed oil (13 kcal), groundnut oil (13 kcal), yams (13 kcal). Note that many of

104-440: Is formed (the A horizon), followed by some mineral horizons (B horizons). Each successive stage is characterized by a certain association of soil/vegetation and environment, which defines an ecosystem . After a certain time of parallel evolution between the ground and the vegetation, a state of steady balance is reached. This stage of development is called climax by some ecologists and "natural potential" by others. Succession

130-543: Is relay cropping. According to the National Library of Medicine, relay cropping may solve a number of conflicts such as inefficient use of available resources, controversies in sowing time, fertilizer application, and soil degradation . The result coming from the use of relay cropping is higher crop output. In the United States, corn is the largest crop produced, and soybean follows in second, according to

156-521: Is the evolution towards climax. Regardless of its name, the equilibrium stage of primary succession is the highest natural form of development that the environmental factors are capable of producing. The cycles of evolution of soils have very variable durations, between tens, hundreds, or thousands of years for quickly evolving soils (A horizon only) to more than a million years for slowly developing soils. The same soil may achieve several successive steady state conditions during its existence, as exhibited by

182-400: Is the main factor for soil degradation and is due to several mechanisms: water erosion, wind erosion , chemical degradation and physical degradation. Erosion can be influenced by human activity. For example, roads which increase impermeable surfaces lead to streaming and ground loss. Improper agriculture practices can also accelerate soil erosion, including by way of: Here are a few of

208-594: The Pygmy forest sequence in Mendocino County, California. Soils naturally reach a state of high productivity , from which they naturally degrade as mineral nutrients are removed from the soil system. Thus older soils are more vulnerable to the effects of induced retrogression and degradation. There are two types of ecological factors influencing the evolution of a soil (through alteration and humification ). These two factors are extremely significant to explain

234-606: The smectite family of clays, to the soil. In field trials, conducted by scientists from the International Water Management Institute (IWMI) in cooperation with Khon Kaen University and local farmers, this had the effect of helping retain water and nutrients. Supplementing the farmer's usual practice with a single application of 200 kg bentonite per rai (6.26 rai = 1 hectare) resulted in an average yield increase of 73%. More work showed that applying bentonite to degraded sandy soils reduced

260-458: The agricultural industry, such as mono cropping, crop rotation, sequential cropping, and mixed intercropping. Each method of cropping has its purposes and possibly disadvantages as well. Himanshu Arora defines mono cropping as where a field only grows one specific crop year round. Mono Cropping has its disadvantages, according to Himanshu Arora, such as the risk of the soil losing its fertility. Following mono cropping, another method of cropping

286-401: The complete destruction of the soil. Man can deeply modify the evolution of the soils by direct and brutal action, such as clearing, abusive cuts , forest pasture, litters raking. The climax vegetation is gradually replaced and the soil modified (example: replacement of leafy tree forests by moors or pines plantations). Retrogression is often related to very old human practices. Soil erosion

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312-486: The consequences of soil regression and degradation: Problems of soil erosion can be fought, and certain practices can lead to soil enhancement and rebuilding. Even though simple, methods for reducing erosion are often not chosen because these practices outweigh the short-term benefits. Rebuilding is especially possible through the improvement of soil structure, addition of organic matter and limitation of runoff. However, these techniques will never totally succeed to restore

338-442: The disturbance undergone by the ecosystem is too important. In this latter case, erosion is responsible for the destruction of the upper horizons of the ground, and is at the origin of a phenomenon of reversion to pioneer conditions. The phenomenon is called retrogression and can be partial or total (in this case, nothing remains beside bare rock). For example, the clearing of an inclined ground, subjected to violent rains, can lead to

364-412: The evolution of soils of short development. The destruction of the vegetation implies the destruction of evoluted soils, or a regressive evolution. Cycles of succession-regression of soils follow one another within short intervals of time (human actions) or long intervals of time (climate variations). The climate role in the deterioration of the rocks and the formation of soils lead to the formulation of

390-452: The globally apparently minor crops are regionally very important. For example, in Africa, roots & tubers dominate with 421 kcal/person/day, and sorghum and millet contribute 135 kcal and 90 kcal, respectively. In terms of produced weight, the following crops are the most important ones (global production in thousand metric tonnes): There are various methods of cropping that are used in

416-668: The government of Alberta. Referring to a map given by the Government of Alberta, the most popular region to grow these popular crops is in the inner states of the U.S., it is where the crops are most successful in output. [REDACTED]  This article incorporates text from a free content work. Licensed under CC BY-SA IGO 3.0 ( license statement/permission ). Text taken from World Food and Agriculture – Statistical Yearbook 2023​ , FAO, FAO. Soil degradation Soil retrogression and degradation are two regressive evolution processes associated with

442-399: The loss of equilibrium of a stable soil . Retrogression is primarily due to soil erosion and corresponds to a phenomenon where succession reverts the land to its natural physical state. Degradation is an evolution, different from natural evolution, related to the local climate and vegetation . It is due to the replacement of primary plant communities (known as climax vegetation ) by

468-423: The main group of crops produced in 2021, followed by sugar crops (22%), vegetables and oil crops (12% each). Fruit, and roots and tubers each accounted for 9–10% of the total production. The increase in production is mostly attributable to a combination of factors; increased use of irrigation, pesticides and fertilizers, and to a lesser extent a larger cultivated area. Other factors such as better farming practices and

494-469: The particles of the ground to their roots. A disturbance of climax will cause retrogression, but often, secondary succession will start to guide the evolution of the system after that disturbance. Secondary succession is much faster than primary because the soil is already formed, although deteriorated and needing restoration as well. However, when a significant destruction of the vegetation takes place (of natural origin such as an avalanche or human origin),

520-427: The quality of 33% of pastureland, 25% of arable land and 23% of forests has deteriorated globally over the last 30 years. 3.2 billion people are dependent on this land. At the beginning of soil formation, the bare rock outcrops are gradually colonized by pioneer species ( lichens and mosses ). They are succeeded by herbaceous vegetation, shrubs, and finally forest . In parallel, the first humus -bearing horizon

546-628: The risk of crop failure during drought years. In 2008, three years after the initial trials, IWMI scientists conducted a survey among 250 farmers in northeast Thailand, half who had applying bentonite to their fields and half who had not. The average output for those using the clay addition was 18% higher than for non-clay users. Using the clay had enabled some farmers to switch to growing vegetables, which need more fertile soil. This helped to increase their income. The researchers estimated that 200 farmers in northeast Thailand and 400 in Cambodia had adopted

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572-728: The secondary communities. This replacement modifies the humus composition and amount, and affects the formation of the soil . It is directly related to human activity. Soil degradation may also be viewed as any change or ecological disturbance to the soil perceived to be deleterious or undesirable. According to the Center for Development Research at the University of Bonn and the International Food Policy Research Institute in Washington,

598-443: The theory of the biorhexistasy. When the state of balance, characterized by the ecosystem climax is reached, it tends to be maintained stable in the course of time. The vegetation installed on the ground provides the humus and ensures the ascending circulation of the matters. It protects the ground from erosion by playing the role of barrier (for example, protection from water and wind ). Plants can also reduce erosion by binding

624-423: The total value in 2021, which is significantly higher than the shares in quantities. The shares of oil crops and roots and tubers in the total value were similar to the shares in quantities. Sugar crops represented 4% of the total value: such a discrepancy with the share of the quantities produced is due to differences in price compared to fruit and vegetables, and to the fact that the transformation into refined sugar

650-406: The use of high-yield crops also play a role. The value of primary crops production increased at a slightly higher pace in real terms as the quantities produced (57%), from USD 1.8 trillion in 2000 to USD 2.8 trillion in 2021. As with quantities produced, cereals accounted for the largest share of the total production value in 2021 (30%). Vegetables and fruit represented 19% and 17%, respectively, of

676-419: Was 9.5 billion tonnes in 2021, 54% more than in 2000. Four crops account for about half of global primary crop production: sugar cane , maize , wheat and rice . The global production of primary crops increased by 54% between 2000 and 2021, to 9.5 billion tonnes, which is 2% higher than in 2020. This represents 3.3 billion tonnes more than in 2000. With slightly less than one-third of the total, cereals were

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