agriculture

what is food security

• a measure of the availability of food and individuals’ ability to access it .

• Food security exists when all people have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life

what is the green revolution

• in the 1950s human population surged, concerns about food security grew, however scientific and technological advances significantly improved crop yields, lading to the green revolution then the third agricultural revolution

• methods that increased yield included: growing high yield crop varieties (modern genetics produced seeds more resilient o disease and drought for higher yields

• using chemical fertilisers and pesticides, reducing limiting factors of crop growth

• developing irrigation infrastructure, supplying more water efficiently to crops

as a result of thee innovations, cereal production and yields increased faster than population with relatively small impact on land use

what is the third agricultural revolution

• a recent period of innovation in agriculture with new technology practices, often focused on increasing efficency

criticisms of the green revolution

• the green evolution increased crop yields for human consumption, but brought environmental problems:

• pesticides not only harm pests but are also harmful to helpful insects needed for soil health

• fertilisers boost output but also contaminate water resources causing eutrophication, producing fertilisers requires the burning of fossil fuels, increasing air pollution and gresshouse gas

  Social problems of the green revolution

• food security increased for many, some food security declined

• The guarani kaiowa tribe in brazil had reliable and sustainable food from their ancestral land, but the tribe was displaced to make way for soybean and other crops. Before the land was not suitable for industrial agriculture but chemicals nd technologies made it possible to farm the land and produce higher yields, the land was taken for large scale farming at the expense of food security for indigenous communities - an issue on environmental justice

factors affects food sustainability

• diets; availability, affordability, culture, religion and emotions. human can digest fungi, plants and meat providing diverse options for interacting with ecological systems to fulfill nutritional needs

• in india 40% of the people are fully vegetarian, plant based diets use less matter and energy to produce as less energy is lost moving up the food chain, ruminant such as pigs and cows emit methane, during digestion

food loss and food waste

• food loss occurs in the global food supply chain during harvest, processing and distribution

• food waste occurs at the retail or consumer stage often from food spoiling before consumption ( this is also contributes t the 10% of anthropocentric greenhouse gas as emissions from carbon dioxide and co2 are released as food decomposes

what are the strategies to improve terrestrial food system sustainability

• reducing demand for unsustainable foods, include producing high quality substitute foods for consumers eg plant based meat, raising awareness of unsustainable foods and taxing them whilst subsiding sustainable alternatives.

• reducing transport emissions, revival of traditional farming techniques combined with scientific understanding of ecological system can improve productivity sustainably

• reducing greenhouse gas emissions, managing timing and method of nitrogen application to crops such as low methane rice, reducing the methane released by ruminants with specially developed feed supplements

reducing food loss and food waste in the food supply chain and beyond

1) farmers, growers and producers

• plant varied, resilient, climate appropriate crops

• use of technologies such as soil probes, gps data and smart irrigation systems to reduce losses to pests, diseases and climate conditions however this is not accessible anywhere

  2) processors

• use better packaging to ensure fresh food arrives undamaged

• improve food expiration labelling to help consumers eat more food before it spoils

  3) retailers

• discount food that is approaching its expiry to sell it quickly

  4) consumers

• plan meal to not over buy food, use local composing solutions

  5) government

• have municipal collection of organic waste to make compost, but not all regions can regularly collect organic waste

• pass laws forbidding and penalising retail food waste

  6) foodbanks

• redistribute excess food from the food supply chain, reducing post harvest waste and improving food security

how to ensure environmental justice

• promoting equitable access to land and seeds

• involving all stakeholders in decision making processes, including women and indigenous communities

• improving market access for small farmera so they can benefit equally from the food supply chain

temperate climate

a biome around 30-60 degrees latitude north and south with four seasons

factors affecting crop choices

1) climate

• climate significantly impacts crop choices, every cultivar is adapted to specific climatic conditions of sunlight, temp, rainfall making it challenging to grow crops outside their native biomes

  2) soils and geography

• agricultural choices reflect opportunities and limitations of an areas physical geography, in areas of poor soils and uneven terrain, farmers may practice nomadic farming moving herds to ensure sufficient grazing.

• where soils are better, farmers don’t need to move around so sedentary farming is more likely where farmers do pastoral farming or arable farming, or mixed farming

• lack of availability can also lead to choosing aquaponic or hydrophonicfarming.

  3) other considerations

• farmers consider sociocultural, technological, economic, political, legal and ethical issues.

• a farmer may use organic practices due to their own values, market demand for organic food, or government subsides for organic food

• they may choose to plant only one crop, a monoculture to make harvesting faster and cheaper, or they may wish to support more diverse ecological systems with polyculture that can reduce pests but slows harvesting

what is sedentary farming

farming done in a single location over many generations

pastoral farming

farming including animals

arable farming

growing crops such as wheat or soy beans

mixed farming

raising both animals and growing crops in the farming system

what is aquaphonic farming

a form of aquaculture that combines raising fish in tanks with the culture of soilless plants

what is hydrophobic farming

the growing of plants without soil

what is intensive farming

an agricultural system aiming to maximise productivity from a given unit of land with relatively high number of inputs ( eg, agrochemicals and labour ) per unit areas of land

what is organic farming

arming methods that do not use fertilisers, pesticides or genetically modified organisms

what is monoculture

the farming of a single crop over an extensive area

what is poly culture

growing may diffrent types of plants together, which can be beneficial for the soil and reduce pests

what local circumstances can influence the type of farming chosen

• intensive farming - farm in a small area with high inputs and outputs, it usually needs high inputs of synthetic fertilisers but aqua phonics is an intensive system using organic nutrients

• extensive farming - farms spread over a large region, it may have high or low inputs or outputs puts. nomadic farming is extensive, as free range live stock farming and very large monoculture farms of grains

• commercial farming - producing foods or sale to earn revenues and profits

• subsistence farming - farms only or mainly produce foods for a family or local community

inputs to agricultural systems

• water - plants and animals need water

• nutrients - synthetic or organic fertilisers provide nitrogen, phosphorus and potassium to plants, in shifting cultivation, nutrients come from remaining organic matter when an area is burned

• labour - can come from humans, animas, tech powered by fossil feuls or renewable energy sources

• seeds - saved from previous crops or purchased, may have been selectively bred or genetically modified to increase yields

• animals - born on the farm, may increase animal stock in pastoral systems or may work the land to supplement human labour

• antibiotics and vaccinations - can prevent disease especially in intensive pastoral farming

• pesticides -pests eg caterpillars may consume crops so farmer may use chemicals to kill them

• hormones - supplementary hormones to increase fruit or animal size, increase milk yields, encourage lean and meat productions or induce early plant flowering

• herbicides - chemicals to remove unwanted plants that use soil nutrients or shad out crops

• energy - can use a lot of energy potentially from fossil fuels, used or equipment such as combine harvesters or aircon, water pumps, and lighting in animal housing

• financial capital - farms may need money to invest in machinery seeds and fertiliser

what is shifting cultivation

also called rotational farming or slash and burn, a method where trees and plants are cut down and burned to plant crops and then given time to regrow and recover soil nutrients while other area of the forest is burned

herbicides

substances that are toxic to plants used to destroy unwanted plants such as weeds

what is a combined harvester

a machine which an harvest crops usually grains, removing and separating the waste pants for the plant

outputs of agricultural systems

• grains, fruits and veg - outputs from arable, hydrophobic and aquaponic farms

• meat and animal products - meat, eggs, milk or labour animals are outputs from pastoral farms

• nutrient run off - excess nutrients, from fertiliser in arable systems or animal faeces from pastoral systems may enter local water bodies creating eutrophication

• chemical contamination - run off pesticides and herbicides can also contaminate local water bodies

• methane gas - is released by ruminants when they digest food and from rice farming in wet fields

• carbon dioxide - burning fossil feuls and the decomposition of organic matter both release carbon dioxide

• economic profit - commercial farms earn revenues from selling their products, profits occur when revenues are higher than costs of production

traditional agricultural systems

• in cultures with traditional lifestyles like nomadic and indigenous groups, food production is extensive and involves managing watersheds, soil, crops and grazing animals

• Example of these methods is rotational farming (aka shifting cultivation or slash and burn) where forests or woodland are cleared for agriculture. This involves setting aside parts of the forest for ecosystem health and water protection , while other areas are cleared and burned to enrich soil nutrients and adjust PH for crops.

• Lands are then left fallow and other areas cleared fr agriculture

• these practices have been used for thousands of years and are sustainable as they are small scale and respect ecosystem health. As indigenous cultures modernise and exist in higher population densities or in fixed locations these practices have become less sustainable

Example of traditional farming

Traditional farming by Baiga people in Madhya Pradesh, India

• Notable for fertile land, diverse biomes and an abundance of rivers is Madhya Paradesh. This variety of land supports the cultivation of a wide range of crops, despite generally low rainfall.

• Traditionally the state has been a hub for growing grains like sorghum, pearl millet, and finger millet - all known for their drought resistance. Pulses (dry beans) such as pigeon pea, black gram, and green gram have been grown for thousands and they increase soil fertility by fixing nitrogen and serving as an important source of proteins for many indians

• Since the green revolution in the 1960s, india has focused on. cultivating rice, wheat and soybeans as major exports leading to a decline of locally grown beans and millets significantly increasing output crops more than any other indian state

• Emerging threats of climate change has renewed interest in restoring traditional crop diversity, including drought resistant varieties

Baiga people and Bewar

• the baiga people practice a form of agriculture named bewar on hillsides which involves burning the natural vegetation to prepare the land for planting crops of millet and beans and moving locations each harvest

• despite efforts and the rich agricultural heritage the tribe face challanges with land rights, development projects such as rigatoni dams have lead to conflicts over land impacting indigenous practices and acess to water, forests and tribal agricultural lands

• the complex interplay of traditional agriculture, modern development and environmental challanges continues to shape the agricultural landscape of Madhya Paradesh

what is meant by degenerative farming practices

• farming in a way that mimics natures processes: returns organic material to the soil, nurtures biodiverse crops and disturbs soil as little as possible to mimic well-functioning ecosystems

preventing loss of nutrients in soil

• cover crops hold soil in place and protect the land from wind and erosion. they can reduce nutrient depletion if they are left to decompose in the soil and not remove as a harvest

• windbreaks, planting tress and bushes will prevent wind erosion, this can be combined by terracing fields to prevent water erosion, the terraces slow down the movement of water so it can soak into soil where crops can use it . Bundling which involves creating raised bed or embankments is another practice used on sloping land to reduce water erosion and run off. Similarly contour ploughing helps stop water from flowing rapidly downhill where nutrients would be lost

• multching is fibrous material, like straw or even cardboard can be laced over soil to protect it from erosion, this strategy also encourages decomposition and so increases nutrients

• drainage canals are used to allow water to be directed away from crops durning heavy rains, reducing erosion and slowing down the movement of water across the landscape.

preventing depletion of soil nutrients

• leaving field fallow, soil is left to rest for a growing season, decomposes release nutrients into the soil before the field is replanted with another crop

• polyculture or mixed cropping can reduce nutrient depletion, some plants have deep roots that bring nutrients to the surface making them more available for plants with shallow roots. other plants. have a mutualistic relationship with fungi ad bacteria which can make scarce nutrients available for all crops. Strip cultivation is where different crops are planted in strips and alternated in crop rotation, cam also be used to prevent soil erosion and improve soil health

• herbal lays which are a sown pasture made up of a mixture of grasses, legumes and herbs, which can be used to increase soil fertility and encourage bio diversity

• mycorrhizae are fungi that form a symbiotic relationship with plant roots, helping the the absorbsion of nutrients and water from the soil. In return plants provide the fungi with carbohydrates. Reaserch shows that mycorrhizae can improve soil structure and soil fertility, helping plants resist diseases and pests, improved crop yields and a reduction in the need for chemical fertilisers

• crop rotation, different crops are planted in the field after each harvest, each plat adds different organic material and removes a different set of nutrients

• zero tillage, involves leaving the remaining organic matter after harvesting in the soil to decompose and return nutrients to the soil

• minimising heavy machinery or livestock, can a sound soil compaction, because compacted, dense soil has less air space and plants struggle with this texture, soil compaction lowers soil PH further reducing nutrients

• agroforestry combined agriculture with tres, this involves grazing livestock or growing crops below trees. The benefits include increased biodiversity, improved soil structure and health and reduced sol erosion, the trees can provide habitats for natural predators to common crop pests and so then the reduced need for pesticides.

• continuous cover forestry is a sustainable approach t managing woodland, it involves selectively thinning tress as apposed to ‘clear felling’ in which most or all trees in the rea are cut down, this method creates a more diverse an resilient forest which can prevent soil compaction and erosion.

replacing soil nutrient methods

• simplest way to increase soil nutrients is to add organic matter, if the soil lacks biodiversity and has been over used, there may not be enough decomposes and detritivores to break down the organic matter for plants to use.

• composting by layering carbon rich materials like straw and wood chips with nitrogen rich materials like grass cuttings, waste food and animal manure. Even human feaces can be used in some circumstances to create humanure, with ample water this compost pile encourages bacteria growth and will quickly decompose to form a nutrient rich loam that can be added to the soils

• cover cropping, also called green manure during fallow periods can add nutrients to the soil, peas, beans and clover engage in mutualism with bacteria to fix the nitrogen in the soil

• live stock grazing, animals grazing on cover crops add nutrients back to the soil from animal feaces, but farmers have to be careful to prevent soil compaction

• adding lime or calcium hydroxide can raise soil ph if its too low, increasing nutrients available to plants