Sustainable agriculture facts for kids
Sustainable agriculture is farming in sustainable ways meeting society's present food and textile needs, without compromising the ability for current or future generations to meet their needs. It can be based on an understanding of ecosystem services. There are many methods to increase the sustainability of agriculture. When developing agriculture within sustainable food systems, it is important to develop flexible business process and farming practices. Agriculture has an enormous environmental footprint, playing a significant role in causing climate change (food systems are responsible for one third of the anthropogenic greenhouse gas emissions), water scarcity, water pollution, land degradation, deforestation and other processes; it is simultaneously causing environmental changes and being impacted by these changes. Sustainable agriculture consists of environment friendly methods of farming that allow the production of crops or livestock without damage to human or natural systems. It involves preventing adverse effects to soil, water, biodiversity, surrounding or downstream resources—as well as to those working or living on the farm or in neighboring areas. Elements of sustainable agriculture can include permaculture, agroforestry, mixed farming, multiple cropping, and crop rotation.
Developing sustainable food systems contributes to the sustainability of the human population. For example, one of the best ways to mitigate climate change is to create sustainable food systems based on sustainable agriculture. Sustainable agriculture provides a potential solution to enable agricultural systems to feed a growing population within the changing environmental conditions. Besides sustainable farming practices, dietary shifts to sustainable diets are an intertwined way to substantially reduce environmental impacts. Numerous sustainability standards and certification systems exist, including organic certification, Rainforest Alliance, Fair Trade, UTZ Certified, GlobalGAP, Bird Friendly, and the Common Code for the Coffee Community (4C).
Definition
The term "sustainable agriculture" was defined in 1977 by the USDA as an integrated system of plant and animal production practices having a site-specific application that will, over the long term:
- satisfy human food and fiber needs
- enhance environmental quality and the natural resource base upon which the agriculture economy depends
- make the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls
- sustain the economic viability of farm operations
- enhance the quality of life for farmers and society as a whole.
Yet the idea of having a sustainable relationship with the land has been prevalent in indigenous communities for centuries before the term was formally added to the lexicon.
Aims
A common consensus is that sustainable farming is the most realistic way to feed growing populations. In order to successfully feed the population of the planet, farming practices must consider future costs–to both the environment and the communities they fuel. The fear of not being able to provide enough resources for everyone led to the adoption of technology within the sustainability field to increase farm productivity. The ideal end result of this advancement is the ability to feed ever-growing populations across the world. The growing popularity of sustainable agriculture is connected to the wide-reaching fear that the planet's carrying capacity (or planetary boundaries), in terms of the ability to feed humanity, has been reached or even exceeded.
Key principles
There are several key principles associated with sustainability in agriculture:
- The incorporation of biological and ecological processes such as nutrient cycling, soil regeneration, and nitrogen fixation into agricultural and food production practices.
- Using decreased amounts of non-renewable and unsustainable inputs, particularly environmentally harmful ones.
- Using the expertise of farmers to both productively work the land as well as to promote the self-reliance and self-sufficiency of farmers.
- Solving agricultural and natural resource problems through the cooperation and collaboration of people with different skills. The problems tackled include pest management and irrigation.
It "considers long-term as well as short-term economics because sustainability is readily defined as forever, that is, agricultural environments that are designed to promote endless regeneration". It balances the need for resource conservation with the needs of farmers pursuing their livelihood.
It is considered to be reconciliation ecology, accommodating biodiversity within human landscapes.
Oftentimes the execution of sustainable practices within farming comes through the adoption of technology and environmentally-focused appropriate technology.
Environmental factors
Practices that can cause long-term damage to soil include excessive tilling of the soil (leading to erosion) and irrigation without adequate drainage (leading to salinization).
The most important factors for a farming site are climate, soil, nutrients and water resources. Of the four, water and soil conservation are the most amenable to human intervention. When farmers grow and harvest crops, they remove some nutrients from the soil. Without replenishment, the land suffers from nutrient depletion and becomes either unusable or suffers from reduced yields. Sustainable agriculture depends on replenishing the soil while minimizing the use or need of non-renewable resources, such as natural gas or mineral ores.
A farm that can "produce perpetually", yet has negative effects on environmental quality elsewhere is not sustainable agriculture. An example of a case in which a global view may be warranted is the application of fertilizer or manure, which can improve the productivity of a farm but can pollute nearby rivers and coastal waters (eutrophication). The other extreme can also be undesirable, as the problem of low crop yields due to exhaustion of nutrients in the soil has been related to rainforest destruction. In Asia, the specific amount of land needed for sustainable farming is about 12.5 acres which include land for animal fodder, cereal production as a cash crop, and other food crops. In some cases, a small unit of aquaculture is included (AARI-1996).
Nutrients
Nitrates
Nitrates are used widely in farming as fertilizer. Unfortunately, a major environmental problem associated with agriculture is the leaching of nitrates into the environment. Possible sources of nitrates that would, in principle, be available indefinitely, include:
- recycling crop waste and livestock or treated human manure
- growing legume crops and forages such as peanuts or alfalfa that form symbioses with nitrogen-fixing bacteria called rhizobia
- industrial production of nitrogen by the Haber process uses hydrogen, which is currently derived from natural gas (but this hydrogen could instead be made by electrolysis of water using renewable electricity)
- genetically engineering (non-legume) crops to form nitrogen-fixing symbioses or fix nitrogen without microbial symbionts.
The last option was proposed in the 1970s, but is only gradually becoming feasible. Sustainable options for replacing other nutrient inputs such as phosphorus and potassium are more limited.
Other options include long-term crop rotations, returning to natural cycles that annually flood cultivated lands (returning lost nutrients) such as the flooding of the Nile, the long-term use of biochar, and use of crop and livestock landraces that are adapted to less than ideal conditions such as pests, drought, or lack of nutrients. Crops that require high levels of soil nutrients can be cultivated in a more sustainable manner with appropriate fertilizer management practices.
Phosphate
Phosphate is a primary component in fertilizer. It is the second most important nutrient for plants after nitrogen, and is often a limiting factor. It is important for sustainable agriculture as it can improve soil fertility and crop yields. Phosphorus is involved in all major metabolic processes including photosynthesis, energy transfer, signal transduction, macromolecular biosynthesis, and respiration. It is needed for root ramification and strength and seed formation, and can increase disease resistance.
Phosphorus is found in the soil in both inorganic and organic forms and makes up approximately 0.05% of soil biomass. Phosphorus fertilizers are the main input of inorganic phosphorus in agricultural soils and approximately 70%–80% of phosphorus in cultivated soils is inorganic. Long-term use of phosphate-containing chemical fertilizers causes eutrophication and deplete soil microbial life, so people have looked to other sources.
Phosphorus fertilizers are manufactured from rock phosphate. However, rock phosphate is a non-renewable resource and it is being depleted by mining for agricultural use: peak phosphorus will occur within the next few hundred years, or perhaps earlier.
Potassium
Potassium is a macronutrient very important for plant development and is commonly sought in fertilizers. This nutrient is essential for agriculture because it improves water retention, nutrient value, yield, taste, color, texture and disease resistance of crops. It is often used in the cultivation of grains, fruits, vegetables, rice, wheat, millets, sugar, corn, soybeans, palm oil and coffee.
Potassium chloride (KCl) represents the most widely source of K used in agriculture, accounting for 90% of all potassium produced for agricultural use.
The use of KCl leads to high concentrations of chloride (Clˉ) in soil harming its health due to the increase in soil salinity, imbalance in nutrient availability and this ion's biocidal effect for soil organisms. In consequences the development of plants and soil organisms is affected, putting at risk soil biodiversity and agricultural productivity. A sustainable option for replacing KCl are chloride-free fertilizers, its use should take into account plants' nutrition needs, and the promotion of soil health.
Soil
Land degradation is becoming a severe global problem. According to the Intergovernmental Panel on Climate Change: "About a quarter of the Earth's ice-free land area is subject to human-induced degradation (medium confidence). Soil erosion from agricultural fields is estimated to be currently 10 to 20 times (no tillage) to more than 100 times (conventional tillage) higher than the soil formation rate (medium confidence)." Almost half of the land on earth is covered with dry land, which is susceptible to degradation. Over a billion tonnes of southern Africa's soil are being lost to erosion annually, which if continued will result in halving of crop yields within thirty to fifty years. Improper soil management is threatening the ability to grow sufficient food. Intensive agriculture reduces the carbon level in soil, impairing soil structure, crop growth and ecosystem functioning, and accelerating climate change. Modification of agricultural practices is a recognized method of carbon sequestration as soil can act as an effective carbon sink.
Soil management techniques include no-till farming, keyline design and windbreaks to reduce wind erosion, reincorporation of organic matter into the soil, reducing soil salinization, and preventing water run-off.
Land
As the global population increases and demand for food increases, there is pressure on land as a resource. In land-use planning and management, considering the impacts of land-use changes on factors such as soil erosion can support long-term agricultural sustainability, as shown by a study of Wadi Ziqlab, a dry area in the Middle East where farmers graze livestock and grow olives, vegetables, and grains.
Looking back over the 20th century shows that for people in poverty, following environmentally sound land practices has not always been a viable option due to many complex and challenging life circumstances. Currently, increased land degradation in developing countries may be connected with rural poverty among smallholder farmers when forced into unsustainable agricultural practices out of necessity.
Converting big parts of the land surface to agriculture has severe environmental and health consequences. For example, it leads to rise in zoonotic disease (like the Coronavirus disease 2019) due to the degradation of natural buffers between humans and animals, reducing biodiversity and creating larger groups of genetically similar animals.
Land is a finite resource on Earth. Although expansion of agricultural land can decrease biodiversity and contribute to deforestation, the picture is complex; for instance, a study examining the introduction of sheep by Norse settlers (Vikings) to the Faroe Islands of the North Atlantic concluded that, over time, the fine partitioning of land plots contributed more to soil erosion and degradation than grazing itself.
The Food and Agriculture Organization of the United Nations estimates that in coming decades, cropland will continue to be lost to industrial and urban development, along with reclamation of wetlands, and conversion of forest to cultivation, resulting in the loss of biodiversity and increased soil erosion.
Energy
In modern agriculture, energy is used in on-farm mechanisation, food processing, storage, and transportation processes. It has therefore been found that energy prices are closely linked to food prices. Oil is also used as an input in agricultural chemicals. The International Energy Agency projects higher prices of non-renewable energy resources as a result of fossil fuel resources being depleted. It may therefore decrease global food security unless action is taken to 'decouple' fossil fuel energy from food production, with a move towards 'energy-smart' agricultural systems including renewable energy. The use of solar powered irrigation in Pakistan is said to be a closed system for agricultural water irrigation.
The environmental cost of transportation could be avoided if people use local products.
Water
In some areas sufficient rainfall is available for crop growth, but many other areas require irrigation. For irrigation systems to be sustainable, they require proper management (to avoid salinization) and must not use more water from their source than is naturally replenishable. Otherwise, the water source effectively becomes a non-renewable resource. Improvements in water well drilling technology and submersible pumps, combined with the development of drip irrigation and low-pressure pivots, have made it possible to regularly achieve high crop yields in areas where reliance on rainfall alone had previously made successful agriculture unpredictable. However, this progress has come at a price. In many areas, such as the Ogallala Aquifer, the water is being used faster than it can be replenished.
According to the UC Davis Agricultural Sustainability Institute, several steps must be taken to develop drought-resistant farming systems even in "normal" years with average rainfall. These measures include both policy and management actions:
- improving water conservation and storage measures
- providing incentives for selection of drought-tolerant crop species
- using reduced-volume irrigation systems
- managing crops to reduce water loss
- not planting crops at all.
Indicators for sustainable water resource development include the average annual flow of rivers from rainfall, flows from outside a country, the percentage of water coming from outside a country, and gross water withdrawal. It is estimated that agricultural practices consume 69% of the world's fresh water.
Challenges
The barriers to sustainable agriculture can be broken down and understood through three different dimensions. These three dimensions are seen as the core pillars to sustainability: social, environmental, and economic pillars. The social pillar addresses issues related to the conditions in which societies are born into, growing in, and learning from. It deals with shifting away from traditional practices of agricultural and moving into new sustainable practices that will create better societies and conditions. The environmental pillar addresses climate change and focuses on agricultural practices that protect the environment for future generations. The economic pillar discovers ways in which sustainable agriculture can be practiced while fostering economic growth and stability, with minimal disruptions to livelihoods. All three pillars must be addressed to determine and overcome the barriers preventing sustainable agricultural practices.
Social barriers to sustainable agriculture include cultural shifts, the need for collaboration, incentives, and new legislation. The move from conventional to sustainable agriculture will require significant behavioural changes from both farmers and consumers.Cooperation and collaboration between farmers is necessary to successfully transition to sustainable practices with minimal complications. This can be seen as a challenge for farmers who care about competition and profitability. There must also be an incentive for farmers to change their methods of agriculture. The use of public policy, advertisements, and laws that make sustainable agriculture mandatory or desirable can be utilized to overcome these social barriers.
Environmental barriers prevent the ability to protect and conserve the natural ecosystem. Examples of these barriers include the use of pesticides and the effects of climate change. Pesticides are widely used to combat pests that can devastate production and plays a significant role in keeping food prices and production costs low. To move toward sustainable agriculture, farmers are encouraged to utilize green pesticides, which cause less harm to both human health and habitats, but would entail a higher production cost. Climate change is also a rapidly growing barrier, one that farmers have little control over, which can be seen through place-based barriers.These place-based barriers include factors such as weather conditions, topography, and soil quality which can cause losses in production, resulting in the reluctance to switch from conventional practices. Many environmental benefits are also not visible or immediately evident. Significant changes such as lower rates of soil and nutrient loss, improved soil structure, and higher levels of beneficial microorganisms take time. In conventional agriculture, the benefits are easily visible with no weeds, pests, etc..., but the long term costs to the soil and surrounding ecosystems are hidden and "externalized". Conventional agricultural practices since the evolution of technology have caused significant damage to the environment through biodiversity loss, disrupted ecosystems, poor water quality, among other harms.
The economic obstacles to implementing sustainable agricultural practices include low financial return/profitability, lack of financial incentives, and negligible capital investments. Financial incentives and circumstances play a large role in whether sustainable practices will be adopted. The human and material capital required to shift to sustainable methods of agriculture requires training of the workforce and making investments in new technology and products, which comes at a high cost. In addition to this, farmers practicing conventional agriculture can mass produce their crops, and therefore maximize their profitability. This would be difficult to do in sustainable agriculture which encourages low production capacity.
The author James Howard Kunstler claims almost all modern technology is bad and that there cannot be sustainability unless agriculture is done in ancient traditional ways. Efforts toward more sustainable agriculture are supported in the sustainability community, however, these are often viewed only as incremental steps and not as an end. One promising method of encouraging sustainable agriculture is through local farming and community gardens. Incorporating local produce and agricultural education into schools, communities, and institutions can promote the consumption of freshly grown produce which will drive consumer demand.
Some foresee a true sustainable steady state economy that may be very different from today's: greatly reduced energy usage, minimal ecological footprint, fewer consumer packaged goods, local purchasing with short food supply chains, little processed foods, more home and community gardens, etc.
Related concepts
Organic agriculture
Organic agriculture can be defined as:
an integrated farming system that strives for sustainability, the enhancement of soil fertility and biological diversity whilst, with rare exceptions, prohibiting synthetic pesticides, antibiotics, synthetic fertilizers, genetically modified organisms, and growth hormones.
Some claim organic agriculture may produce the most sustainable products available for consumers in the US, where no other alternatives exist, although the focus of the organics industry is not sustainability.
In 2018 the sales of organic products in USA reach $52.5 billion According to a USDA survey two-thirds of Americans consume organic products at least occasionally.
Ecological farming
Ecological farming is a concept that focused on the environmental aspects of sustainable agriculture. Ecological farming includes all methods, including organic, which regenerate ecosystem services like: prevention of soil erosion, water infiltration and retention, carbon sequestration in the form of humus, and increased biodiversity. Many techniques are used including no-till farming, multispecies cover crops, strip cropping, terrace cultivation, shelter belts, pasture cropping etc.
There are a plethora of methods and techniques that are employed when practicing ecological farming, all having their own unique benefits and implementations that lead to more sustainable agriculture. Crop genetic diversity is one method that is used to reduce the risks associated with monoculture crops, which can be susceptible to a changing climate. This form of biodiversity causes crops to be more resilient, increasing food security and enhancing the productivity of the field on a long-term scale. The use of biodigestors is another method which converts organic waste into a combustible gas, which can provide several benefits to an ecological farm: it can be used as a fuel source, fertilizer for crops and fish ponds, and serves as a method for removing wastes that are rich in organic matter. Because biodigestors can be used as fertilizer, it reduces the amount of industrial fertilizers that are needed to sustain the yields of the farm. Another technique used is aquaculture integration, which combines fish farming with agricultural farming, using the wastes from animals and crops and diverting them towards the fish farms to be used up instead of being leeched into the environment. Mud from the fish ponds can also be used to fertilize crops.
Organic Fertilizers can also be employed in an ecological farm, such as animal and green manure. This allows soil fertility to be improved and well-maintained, leads to reduced costs and increased yields, reduces the usage of non-renewable resources in industrial fertilizers (Nitrogen and Phosphorus), and reduces the environmental pressures that are posed by intensive agricultural systems. Precision Agriculture can also be used, which focuses on efficient removal of pests using non-chemical techniques and minimizes the amount of tilling needed to sustain the farm. An example of a precision machine is the false seedbed tiller, which can remove a great majority of small weeds while only tilling one centimeter deep. This minimized tilling reduces the amount of new weeds that germinate from soil disturbance. Other methods that reduce soil erosion include contour farming, strip cropping, and terrace cultivation.
Benefits
- Ecological farming involves the introduction of symbiotic species, where possible, to support the ecological sustainability of the farm. Associated benefits include a reduction in ecological debt and elimination of dead zones.
- Ecological farming is a pioneering, practical development which aims to create globally sustainable land management systems, and encourages review of the importance of maintaining biodiversity in food production and farming end products.
- One foreseeable option is to develop specialized automata to scan and respond to soil and plant situations relative to intensive care for the soil and the plants. Accordingly, conversion to ecological farming may best utilize the information age, and become recognised as a primary user of robotics and expert systems.
Challenges
The challenge for ecological farming science is to be able to achieve a mainstream productive food system that is sustainable or even regenerative. To enter the field of ecological farming, location relative to the consumer, can reduce the food miles factor to help minimise damage to the biosphere by combustion engine emissions involved in current food transportation.
Design of the ecological farm is initially constrained by the same limitations as conventional farming: local climate, the soil's physical properties, budget for beneficial soil supplements, manpower and available automatons; however long-term water management by ecological farming methods is likely to conserve and increase water availability for the location, and require far fewer inputs to maintain fertility.
Principles
Certain principles unique to ecological farming need to be considered.
- Food production should be ecological in both origin and destiny (the term destiny refers to the post-harvest ecological footprint which results in getting produce to the consumer).
- Integration of species that maintain ecosystem services whilst providing a selection of alternative products.
- Minimise food miles, packaging, energy consumption and waste.
- Define a new ecosystem to suit human needs using lessons from existing ecosystems from around the world.
- Apply the value of a knowledge-base (advanced data base) about soil microorganisms so that discoveries of the ecological benefits of having various kinds of microorganisms encouraged in productive systems such as Forest Gardens can be assessed and optimised; for example in the case of naturally occurring microorganisms called denitrifiers.
See also
In Spanish: Agricultura sostenible para niños
- Agroecology
- Climate-smart agriculture
- Environmental impact of meat production
- Forest farming
- Local food
- Natural farming
- Sustainable Agriculture Innovation Network (between the UK and China)
- Sustainable Commodity Initiative
- Sustainable development
- Sustainable energy
- Sustainable food system
- Sustainable landscaping
