ABSTRACT
Vietnam's agriculture is an intensive sector, annually producing more than 160 million tons of by-products, of which over 50% are by-products of the cultivation industry. This presents a significant challenge for sustainable agricultural development, given that the circular economy in agriculture is not yet widely adopted. The paper has reviewed the theoretical concepts of the contribution of circular agriculture to sustainable development, existing initiatives in practice, difficulties in implementation, and proposed several prospects and policy solutions to implement circular economy in agriculture in Vietnam.
Keywords: circular agriculture, by-products, sustainable development, Vietnam
INTRODUCTION
Food security, measured by the availability and accessibility of food to individuals, has been and will continue to be a constant challenge for humanity. On the one hand, the increase in global population from 7.6 billion in 2017 to 11.2 billion in 2100 (UN, 2017) requires increased food production. On the other hand, the current food production structure is not sustainable enough and still requires review. In addition, another major challenge that must be mentioned is the global decline in soil fertility, which is exacerbated by increasing water scarcity and environmental pollution (DeLong et al., 2015).
Changes in land use, such as deforestation and conversion of natural grasslands to cropland, are not viable solutions because they cause environmental disasters and the loss of many natural landscapes (UNFCC, 2021). Fertilizers and pesticides do improve food security, especially in the short term, but can be dangerous in the long term, for example by reducing biodiversity, reducing soil quality and leading to health risks for consumers (Foley et al. 2005). Ultimately, climate change will have a significant and potentially destabilizing impact on key crops (Rahmann et al., 2017). In the Sustainable Development Goals, the United Nations has identified these challenges and proposed that all food systems need to change towards intensive and sustainable farming, focusing on circular economic models (UN, 2015).
Circular agriculture with sustainable development
Circular agriculture, also known as a circular economy in agriculture, is a closed-loop agricultural production process. In which, waste or by-products of one production process are reused as input materials for another production process, thanks to the application of science and technology (biotechnology, physicochemical technology). Thus, in theory, circular agricultural production will save resources, minimize waste, and reduce the risk of environmental pollution. This is also a key component of sustainable development.
The question is, is circular agriculture a complete solution for sustainable agricultural development, and how does circular agriculture impact sustainable agricultural development?
The significant and sustained increase in global food production over recent decades has come at a high environmental cost. Half of all habitable land is currently used for agriculture. Due to rapid growth in agricultural production, one-third of global forest cover has been lost over the past century and 20% of forest stands have been degraded between 1990 and 2015. The consequence of deforestation is loss of biodiversity. Conversion of natural habitats to agricultural land accounted for 60–70% of the total biodiversity loss during this period (UN, 2015).
Global use of freshwater resources has increased nearly sixfold over the past century, more than twice the rate of population growth during the same period. Agriculture accounts for approximately 70% of the freshwater extracted globally.
The growth of agriculture has also been fueled by the greater use of chemical fertilizers and synthetic pesticides, which, over time, have eroded the quality of arable land. The global use of chemical fertilizers has increased from approximately 12 million tons in 1961 to more than 110 million tons in 2018. Fertilizer use per hectare has increased across developing regions, with the greatest growth in Asia, led by China and India. This is in sharp contrast to sub-Saharan Africa, where fertilizer use remains low, increasing from 11 kg/ha of arable land in 2000, to 16 kg/ha in 2018 (UN, 2021).
Circular agriculture focuses on using minimal external inputs, closing nutrient loops, regenerating soil, and minimizing environmental impact. If implemented on a large scale, circular agriculture can reduce resource requirements and the ecological footprint of agriculture. It can also help ensure reduced use of land, chemical fertilizers and waste, helping to reduce CO2 emissions globally. In Europe, it is estimated that a circular approach to the food system could reduce the use of chemical fertilizers by 80% (Ellen MacArthur Foundation, 2016).
In a circular economy, reusing and recycling materials are not just a separate step to closing the loop, but are also an integral part of the choices made during the production and use stages. In circular agriculture, this could be the use of manure as organic fertilizer and the use of wastewater in irrigation.
Circular agriculture is not a new concept and was widely adopted in pre-industrial societies. However, it has been pushed aside by modern agriculture based on large-scale, monocropping and highly intensive farming, often with an emphasis on profit maximization rather than environmental protection. The business models of large-scale, specialized agricultural companies are generally not well suited to circular agriculture. The shift to circular agriculture requires greater emphasis on promoting smallholder farming, associated with organic, mixed and agroforestry farming practices. Circular agriculture, with its more diverse production, is associated with better health and nutrition, as opposed to export-oriented monoculture production, which often leads to increased food insecurity (Meemken and Qaim, 2018).
Circular agriculture also uses more labor than conventional farming, which offers a strategy to stimulate the economy in rural areas. Therefore, the application of circular farming practices can make an important contribution to poverty reduction, ensuring food security and creating new employment opportunities, especially for rural women. According to FAO, women account for 48% of agricultural employment in low-income countries, but face greater limitations than men in accessing productive and technological resources and services, market information and financial assets. While conventional farming often requires significant capital to purchase expensive seeds, fertilizers, and pesticides, adopting circular agriculture practices can lower the barriers for women to enter this field as it requires less input.
In circular agriculture, all steps of the food system from growing, harvesting, packaging, processing, transporting, marketing, consuming and handling food are designed to promote sustainable development. The integration of mixed crop and livestock farming and organic farming, agroforestry and water recycling and wastewater reuse is a key element of the circular agriculture model to reduce CO2 emissions, using natural resources more efficiently and significantly cutting input use.
Mixed farming
Circular agriculture is closely connected to the concept of mixed crop-livestock farming. For example, mixed farming may imply a shift from monoculture agriculture to the cultivation of a series of interdependent crops, where the cultivation of one crop facilitates the growth of the others grown on the same land. Crop diversity becomes an effective method to reduce inputs, manage soil fertility and increase resilience, while the combined production of different crops and legumes, can sustainably increase productivity.
Mixed farming combining crops with livestock offers more opportunities to enhance circular agriculture. For example, using domestically produced animal feed and fertilizers instead of imported and chemical fertilizers can contribute to reducing CO 2 emissions in agriculture. The goal is to harness the synergy between crops and livestock to create a circular food system.
Mixed farming practices, despite their numerous benefits, are being increasingly replaced by highly specialized agricultural systems. Mixed crop and livestock farms tend to have lower costs, are less sensitive to market and price fluctuations, and have lower pollution levels. Although the context and mixed farming systems themselves have changed over time, such an approach can ensure more sustainable agricultural and rural development.
Organic agriculture
Organic farming is another important element of circular agriculture, which strives to eliminate dependence on chemical fertilizers, pesticides and plastics. Organic farming also typically requires more labor, thereby providing employment and development opportunities in rural areas. Reducing the use of pesticides and fertilizers can also have implications for promoting gender equality. In many parts of the world, handling pesticides is considered men's work, so pesticide-free organic farming can promote women's participation in agriculture (Meemken and Qaim, 2018).
Yields in conventional farming (using inorganic chemicals) have historically been significantly higher than in organic farming. However, this difference has decreased in recent years (Robertson et al., 2004). Under certain conditions and management practices and for crop groups such as rice, soybeans, corn and clover, organic farming comes close to conventional agricultural systems in terms of productivity and land requirements (Reganold and Wachter, 2016). Techniques such as rotational farming, mulching, polyculture, and polyculture in organic systems further reduce variation in productivity and land use efficiency (Ponisio et al., 2015).
A total of 72.3 million hectares were managed organically in 2019, compared to 11 million hectares in 1999. Despite rapid growth, many obstacles remain to the wider adoption of organic farming, including vested interests and current policies, a lack of information and knowledge, poor infrastructure, as well as misconceptions and cultural biases. Organic agriculture also receives less research and public and private investment than conventional agricultural methods, especially in developing countries.
Combined Agroforestry
Agroforestry, defined as the cultivation of perennial crops in combination with other crops or pastures, is an integral part of circular agriculture. Planting perennial crops can help restore biodiversity in agricultural landscapes, while also increasing soil fertility by enhancing the accumulation of naturally decomposing organic matter. Agroforestry can also make agriculture more circular by reducing dependence on chemical fertilizers and pesticides. As agroforestry reduces input needs, women farmers who often have fewer financial resources and limited access to credit will become more accessible, which may provide new opportunities for rights for women in the rural economy. Additionally, collecting firewood and fodder is primarily the responsibility of women in rural areas worldwide. Agroforestry makes these products available on the farm, thereby reducing the time women spend on such activities, which can contribute to their empowerment.
Agroforestry combined with livestock farming offers the opportunity to adopt circular agriculture with a lower ecological impact. Many small farmers raise livestock, and they often use crop residue biomass as livestock feed, which reduces available land cover. However, with trees growing on their farms, there will be more biomass to meet livestock needs and maintain continuous land cover. Agroforestry can also reduce the need for plastic mulch by using leaves and other plants as organic mulch.
Recycling and reuse of irrigation water are important components of circular agricultural water management. The use of wastewater in agriculture has the potential to irrigate an additional 40 million hectares or 15% of the total irrigated land area. Reusing wastewater for agricultural purposes can reduce pollution, ensure greater water conservation, and provide additional sources to recharge aquifers.
Counter-flow systems where excess drainage and irrigation are redirected back into the irrigation network are also an integral element of circular agriculture. However, water recycling plants often consume a significant amount of energy and produce sludge that is challenging to remove. Newer technologies can alleviate this problem by developing new sludge with products that promote recycling at zero energy costs by capturing biogas. Biogas, a byproduct of the treatment process, can be used to offset a facility's energy consumption. These advances offer new opportunities not only to close the water cycle but also to reduce carbon emissions, energy costs, and environmental pollutants.
Some issues raised when developing circular economy in agriculture in Vietnam
According to recent studies, the development of circular economy in agriculture in Vietnam is facing the following problems:
Firstly, the awareness of state management agencies, businesses and farmers about circular agriculture is incomplete. In our country, the seeds of circular economy in agriculture have existed since the early 1980s of the twentieth century, but the term “circular agriculture” has just been mentioned. Therefore, the role, benefits, nature, content, and criteria of circular agriculture are unclear, leading to a vague and incomplete understanding of the circular economy among relevant stakeholders in agriculture. This is one of the barriers to developing circular agriculture in Vietnam.
Secondly, there is no motivation to develop a circular economy in agriculture. Recently, our country’s agricultural production has been gradually shifting its focus to sustainable and organic agriculture; however, it still primarily emphasizes output through increased inputs. Therefore, agricultural production still relies mainly on resource exploitation and the use of growth stimulants, pesticides, and inorganic fertilizers, which has not created a motivation to apply a circular economy in agriculture.
Thirdly, the capacity to recycle and reuse agricultural byproducts and waste products remains limited. Currently, our country lacks a team of staff to research, apply, and transfer technology for treating waste and by-products in agriculture. In addition, since the scale of agricultural production is small, the collection and classification of agricultural waste, as well as investment in recycling technology, have not been paid attention to. Agricultural enterprises are largely limited in recycling and reuse technology as well as capital and human resources, so they are interested in recovering and reusing main by-products in the production process. Some localities have not prioritized waste management or provided technical training and guidance for production facilities. Therefore, currently only about 10% of crop by-products are reused as local fuel, 5% as industrial fuel, 3% as animal feed; more than 80% are not reused and are discharged directly into the environment or burned, causing environmental pollution (Reganold, John P., and Jonathan M. Wachter, 2016).
Fourthly, there is a lack of guidance and standardization for implementing a circular economy in agriculture. Up to now, the circular economy in the world has been applied by many countries, but in Vietnam it is still relatively new, especially in the field of agriculture. Therefore, circular economy models applied in agriculture are not complete and spontaneous. There have been no regulations or criteria for identification and evaluation, nor has there been a focal agency on this issue, while the circular economy in agriculture involves many fields. Currently, regulations related to the circular economy in general and circular agriculture in particular are scattered in different laws and decrees. Besides, funding conditions are still limited, making it very difficult to deploy and develop a circular economy in the economy in general and agriculture in particular.
Prospects for developing circular agriculture in Vietnam
Circular agriculture for Vietnam is neither new nor novel. It is not new because, circular agricultural production models have been applied in Vietnam for many years. The earliest can be mentioned as the Garden - Pond - Barn model (also known as the VAC model), the VAC combined forest model (VACR), which has been widely deployed since the 1980s. Next is the livestock model combined with biogas in the 2000s. In addition, due to natural conditions, many regions of Vietnam still apply combined crop and livestock models, such as cows with corn, rice with fish, and rice with shrimp.
It can be said that the above combined models represent a form of intensive farming, creating an overall farming system that effectively utilizes land and water resources, helping farmers achieve higher economic efficiency with low investment. At the same time, they contribute to partially reducing environmental pollution problems in livestock farming.
However, if understood in the agricultural sense of the future, the above-mentioned combined production models, often at a household scale, can only be considered a primitive level of circular agriculture. There is a lack of science and technology applied to the production process. To develop modern agriculture, circular agriculture needs to be linked with high-tech agriculture, used at the farm scale, and promote links with businesses.
Regarding the institutional environment, Vietnam does not have its own policies for circular agriculture, but some policies support the development of circular agriculture. For example, the Vietnam Sustainable Development Strategy 2011-2020; Environmental Protection Strategy to 2020, vision to 2030; Green growth strategy; Decree No. 38/2015/ND-CP of the Government: On waste and scrap management; Decision No. 16/2015/QD-TTg on recall and treatment of discarded products; or the National Strategy on Integrated Solid Waste Management 2018.
In Vietnam, the total amount of agricultural by-products is estimated to be nearly 160 million tons. Of which, more than half is post-harvest by-products from crops and from the processing of agricultural products in the farming industry; almost 40% are livestock and poultry waste from the livestock industry, the rest is by-products from the forestry and fisheries industry. This is the reason, and also the premise for developing circular agriculture. Currently, the utilization of crop residues and animal wastes is relatively low, resulting in a partial underutilization of resources, increased emissions, and environmental pollution. In order to strengthen circular system and reuse these resources, we need to incorporate very well two sub-sectors of crops and livestock, and combine national policies to create a clear policy corridor and increase income from animal wastes and crop residues in farms to reduce pollution and obtain organic agriculture towards a circular economy and sustainable agriculture. Some current practices of circular systems, such as, production of organic fertilizers from animal wastes and crop residues, incorporation of rice straw into the soil, stove gasification and carbonization for renewable energy and biochar, organic agriculture and circulated farm showing many advantages of effectively use animal wastes and crop residues for agriculture production to reduce environmental pollution, enhance soil fertility, generate clean energy and reduce synthetic fertilizers as well as reducing GHG emissions.
CONCLUSION AND RECOMMENDATIONS
Over the years, Vietnamese agriculture has always maintained a central position in ensuring national food security, providing raw materials for the processing industry and export. Developing circular agriculture will be a vital trend for sustainable agricultural development. There are some policy recommendations:
Firstly, raise awareness among state agricultural management agencies, businesses and farmers about the circular economy in agriculture. It is necessary to develop a communication strategy about the circular economy model in agriculture, including role, benefits, nature, content, criteria, implementation methods and etc. After that, promote propaganda through mass media, training programs at all levels, from high school to university, agricultural training classes, and agricultural extension programs. Depending on each subject and area, there are different appropriate measures; for example, state management agencies in charge of agriculture, and businesses visit and study the experiences of some countries or domestic companies that have successfully implemented circular agriculture; guide farmers depending on the area (plain, midland, mountainous, coastal) to choose effective models of utilizing agricultural byproducts and waste products.
Secondly, create incentives for localities, businesses, and farmers to invest in circular agriculture. Support in capital, technology, and market; guiding businesses and farmers to carry out agricultural production along the value chain in each cycle: from production, distribution consumption to recycling. Promote the implementation and replication of production models using agricultural waste to grow mushrooms, soybeans, corn, potatoes, and etc.; Encourage the expansion of organic agricultural production models, clean agriculture, and high-tech agriculture; Recommend and even ban the burning of straw in the fields, and forbid livestock facilities from discharging waste that causes pollution.
Thirdly, improve the capacity to recycle and reuse agricultural by-products and waste products. Training and fostering a workforce to research and deploy technology for processing by-products and waste products in agriculture. Invest in research and the transfer of science and technology for agricultural waste treatment, particularly in areas with large-scale cultivation and livestock operations. Advise and support (premises, capital, technology) agricultural production entities so that they focus on collecting, classifying agricultural waste and waste products as well as investing in recycling technology. Encourage localities across the country, based on existing models and their specific conditions, to develop appropriate circular economy models in agriculture. Promote links between businesses and farmers. Encourage businesses and corporations with great potential to invest in exploiting and processing agricultural by-products to create organic fertilizers and substrates; promote advanced, environmentally friendly production processes; Build and replicate models of using mixed animal feed and biological products to replace antibiotics in livestock and aquaculture.
Fourthly, build a legal corridor by integrating circular economy into Nationally Determined Contribution (NDC) is necessary. The policy should also build standards of circular economy in agriculture. To promote a circular economy in agricultural development, the State plays a crucial role in establishing a transparent, stable, and favorable legal framework to attract businesses, industry organizations, and individuals to participate. It is determined that businesses play a central role and serve as the core nucleus. The State creates a business environment through mechanisms and policies to develop clean technology, promote reuse, and recycle waste, ensuring that waste becomes a resource in both production and consumption aspects of the economy. There must be a policy to prioritize businesses investing in recycling technology for some high-value agricultural by-products.
REFERENCES
DeLong C, Cruse R, Wiener J (2015) The soil degradation paradox: compromising our resources when we need them the most. Sustainability 7(1):866–879. https://doi.org/10.3390 /su7010866
Ellen MacArthur Foundation (2016). Cities and circular economy for food. https://www.ellenmacarthurfoundation.org/publications/cities-and-circular-economy-for-food.
FAO (2016). Save and grow in practice: maize, rice, wheat: A guide to sustainable cereal production. Rome.
FAO (2021) FAO’s work on Climate Change. https://www.fao.org/climate-change/en/
FAO & ICRAF (2019). Agroforestry and tenure. Forestry Working Paper, No. 8. Rome.
Foley JA, Defries R, Asner GP, Barford C, Bonan G, Carpenter SR, Chapin FS, Coe MT, Daily GC, Gibbs HK, Helkowski JH, Holloway T, Howard EA, Kucharik CJ, Monfreda C, Patz JA, Prentice IC, Ramankutty N, Snyder PK (2005) Global consequences of land use. Science (NY) 309(5734): 570–574. https://doi.org/10.1126/science.1111772
Meemken, Eva-Marie, and Matin Qaim (2018). Organic agriculture, food security and the environment. Annual Review of Resource Economics, vol. 10: 39–63.
Ponisio, L., and others (2015). Diversification practices reduce organic to conventional yield gap. Proceedings of the Royal Society B: Biological Sciences 282 (1799).
Rahmann G, Reza AM, Bàrberi P, Boehm H, Canali S, Chander M et al (2017) Organic agriculture 3.0 is innovation with research. Org Agric 7(3):169–197. https://doi.org/10.1007 /s13165-016-0171-5
Reganold, John P., and Jonathan M. Wachter (2016). Organic agriculture in the twenty-first century. Nature Plants 2(2):1–8.
Robertson, K.L, and others (2004). Farming for ecosystem services: an ecological approach to production agriculture. Bioscience, 2014, pp. 61–65
UN (2015) Transforming our world: the 2030 Agenda for Sustainable Development. https://sdgs.un.org/2030agenda
UN (2017) World population prospects: the 2017 revision. Key findings & advance tables. Edited by United Nations, Department of Economic and Social Affairs, Population Division. United Nations. New York
UNFCC (2021) Land Use, Land-Use Change and Forestry (LULUCF). Land Use, Land-Use Change and Forestry (LULUCF) | UNFCC
Circular Agriculture with Sustainable Agricultural Development and Prospects for Vietnam
ABSTRACT
Vietnam's agriculture is an intensive sector, annually producing more than 160 million tons of by-products, of which over 50% are by-products of the cultivation industry. This presents a significant challenge for sustainable agricultural development, given that the circular economy in agriculture is not yet widely adopted. The paper has reviewed the theoretical concepts of the contribution of circular agriculture to sustainable development, existing initiatives in practice, difficulties in implementation, and proposed several prospects and policy solutions to implement circular economy in agriculture in Vietnam.
Keywords: circular agriculture, by-products, sustainable development, Vietnam
INTRODUCTION
Food security, measured by the availability and accessibility of food to individuals, has been and will continue to be a constant challenge for humanity. On the one hand, the increase in global population from 7.6 billion in 2017 to 11.2 billion in 2100 (UN, 2017) requires increased food production. On the other hand, the current food production structure is not sustainable enough and still requires review. In addition, another major challenge that must be mentioned is the global decline in soil fertility, which is exacerbated by increasing water scarcity and environmental pollution (DeLong et al., 2015).
Changes in land use, such as deforestation and conversion of natural grasslands to cropland, are not viable solutions because they cause environmental disasters and the loss of many natural landscapes (UNFCC, 2021). Fertilizers and pesticides do improve food security, especially in the short term, but can be dangerous in the long term, for example by reducing biodiversity, reducing soil quality and leading to health risks for consumers (Foley et al. 2005). Ultimately, climate change will have a significant and potentially destabilizing impact on key crops (Rahmann et al., 2017). In the Sustainable Development Goals, the United Nations has identified these challenges and proposed that all food systems need to change towards intensive and sustainable farming, focusing on circular economic models (UN, 2015).
Circular agriculture with sustainable development
Circular agriculture, also known as a circular economy in agriculture, is a closed-loop agricultural production process. In which, waste or by-products of one production process are reused as input materials for another production process, thanks to the application of science and technology (biotechnology, physicochemical technology). Thus, in theory, circular agricultural production will save resources, minimize waste, and reduce the risk of environmental pollution. This is also a key component of sustainable development.
The question is, is circular agriculture a complete solution for sustainable agricultural development, and how does circular agriculture impact sustainable agricultural development?
The significant and sustained increase in global food production over recent decades has come at a high environmental cost. Half of all habitable land is currently used for agriculture. Due to rapid growth in agricultural production, one-third of global forest cover has been lost over the past century and 20% of forest stands have been degraded between 1990 and 2015. The consequence of deforestation is loss of biodiversity. Conversion of natural habitats to agricultural land accounted for 60–70% of the total biodiversity loss during this period (UN, 2015).
Global use of freshwater resources has increased nearly sixfold over the past century, more than twice the rate of population growth during the same period. Agriculture accounts for approximately 70% of the freshwater extracted globally.
The growth of agriculture has also been fueled by the greater use of chemical fertilizers and synthetic pesticides, which, over time, have eroded the quality of arable land. The global use of chemical fertilizers has increased from approximately 12 million tons in 1961 to more than 110 million tons in 2018. Fertilizer use per hectare has increased across developing regions, with the greatest growth in Asia, led by China and India. This is in sharp contrast to sub-Saharan Africa, where fertilizer use remains low, increasing from 11 kg/ha of arable land in 2000, to 16 kg/ha in 2018 (UN, 2021).
Circular agriculture focuses on using minimal external inputs, closing nutrient loops, regenerating soil, and minimizing environmental impact. If implemented on a large scale, circular agriculture can reduce resource requirements and the ecological footprint of agriculture. It can also help ensure reduced use of land, chemical fertilizers and waste, helping to reduce CO2 emissions globally. In Europe, it is estimated that a circular approach to the food system could reduce the use of chemical fertilizers by 80% (Ellen MacArthur Foundation, 2016).
In a circular economy, reusing and recycling materials are not just a separate step to closing the loop, but are also an integral part of the choices made during the production and use stages. In circular agriculture, this could be the use of manure as organic fertilizer and the use of wastewater in irrigation.
Circular agriculture is not a new concept and was widely adopted in pre-industrial societies. However, it has been pushed aside by modern agriculture based on large-scale, monocropping and highly intensive farming, often with an emphasis on profit maximization rather than environmental protection. The business models of large-scale, specialized agricultural companies are generally not well suited to circular agriculture. The shift to circular agriculture requires greater emphasis on promoting smallholder farming, associated with organic, mixed and agroforestry farming practices. Circular agriculture, with its more diverse production, is associated with better health and nutrition, as opposed to export-oriented monoculture production, which often leads to increased food insecurity (Meemken and Qaim, 2018).
Circular agriculture also uses more labor than conventional farming, which offers a strategy to stimulate the economy in rural areas. Therefore, the application of circular farming practices can make an important contribution to poverty reduction, ensuring food security and creating new employment opportunities, especially for rural women. According to FAO, women account for 48% of agricultural employment in low-income countries, but face greater limitations than men in accessing productive and technological resources and services, market information and financial assets. While conventional farming often requires significant capital to purchase expensive seeds, fertilizers, and pesticides, adopting circular agriculture practices can lower the barriers for women to enter this field as it requires less input.
In circular agriculture, all steps of the food system from growing, harvesting, packaging, processing, transporting, marketing, consuming and handling food are designed to promote sustainable development. The integration of mixed crop and livestock farming and organic farming, agroforestry and water recycling and wastewater reuse is a key element of the circular agriculture model to reduce CO2 emissions, using natural resources more efficiently and significantly cutting input use.
Mixed farming
Circular agriculture is closely connected to the concept of mixed crop-livestock farming. For example, mixed farming may imply a shift from monoculture agriculture to the cultivation of a series of interdependent crops, where the cultivation of one crop facilitates the growth of the others grown on the same land. Crop diversity becomes an effective method to reduce inputs, manage soil fertility and increase resilience, while the combined production of different crops and legumes, can sustainably increase productivity.
Mixed farming combining crops with livestock offers more opportunities to enhance circular agriculture. For example, using domestically produced animal feed and fertilizers instead of imported and chemical fertilizers can contribute to reducing CO 2 emissions in agriculture. The goal is to harness the synergy between crops and livestock to create a circular food system.
Mixed farming practices, despite their numerous benefits, are being increasingly replaced by highly specialized agricultural systems. Mixed crop and livestock farms tend to have lower costs, are less sensitive to market and price fluctuations, and have lower pollution levels. Although the context and mixed farming systems themselves have changed over time, such an approach can ensure more sustainable agricultural and rural development.
Organic agriculture
Organic farming is another important element of circular agriculture, which strives to eliminate dependence on chemical fertilizers, pesticides and plastics. Organic farming also typically requires more labor, thereby providing employment and development opportunities in rural areas. Reducing the use of pesticides and fertilizers can also have implications for promoting gender equality. In many parts of the world, handling pesticides is considered men's work, so pesticide-free organic farming can promote women's participation in agriculture (Meemken and Qaim, 2018).
Yields in conventional farming (using inorganic chemicals) have historically been significantly higher than in organic farming. However, this difference has decreased in recent years (Robertson et al., 2004). Under certain conditions and management practices and for crop groups such as rice, soybeans, corn and clover, organic farming comes close to conventional agricultural systems in terms of productivity and land requirements (Reganold and Wachter, 2016). Techniques such as rotational farming, mulching, polyculture, and polyculture in organic systems further reduce variation in productivity and land use efficiency (Ponisio et al., 2015).
A total of 72.3 million hectares were managed organically in 2019, compared to 11 million hectares in 1999. Despite rapid growth, many obstacles remain to the wider adoption of organic farming, including vested interests and current policies, a lack of information and knowledge, poor infrastructure, as well as misconceptions and cultural biases. Organic agriculture also receives less research and public and private investment than conventional agricultural methods, especially in developing countries.
Combined Agroforestry
Agroforestry, defined as the cultivation of perennial crops in combination with other crops or pastures, is an integral part of circular agriculture. Planting perennial crops can help restore biodiversity in agricultural landscapes, while also increasing soil fertility by enhancing the accumulation of naturally decomposing organic matter. Agroforestry can also make agriculture more circular by reducing dependence on chemical fertilizers and pesticides. As agroforestry reduces input needs, women farmers who often have fewer financial resources and limited access to credit will become more accessible, which may provide new opportunities for rights for women in the rural economy. Additionally, collecting firewood and fodder is primarily the responsibility of women in rural areas worldwide. Agroforestry makes these products available on the farm, thereby reducing the time women spend on such activities, which can contribute to their empowerment.
Agroforestry combined with livestock farming offers the opportunity to adopt circular agriculture with a lower ecological impact. Many small farmers raise livestock, and they often use crop residue biomass as livestock feed, which reduces available land cover. However, with trees growing on their farms, there will be more biomass to meet livestock needs and maintain continuous land cover. Agroforestry can also reduce the need for plastic mulch by using leaves and other plants as organic mulch.
Recycling and reuse of irrigation water are important components of circular agricultural water management. The use of wastewater in agriculture has the potential to irrigate an additional 40 million hectares or 15% of the total irrigated land area. Reusing wastewater for agricultural purposes can reduce pollution, ensure greater water conservation, and provide additional sources to recharge aquifers.
Counter-flow systems where excess drainage and irrigation are redirected back into the irrigation network are also an integral element of circular agriculture. However, water recycling plants often consume a significant amount of energy and produce sludge that is challenging to remove. Newer technologies can alleviate this problem by developing new sludge with products that promote recycling at zero energy costs by capturing biogas. Biogas, a byproduct of the treatment process, can be used to offset a facility's energy consumption. These advances offer new opportunities not only to close the water cycle but also to reduce carbon emissions, energy costs, and environmental pollutants.
Some issues raised when developing circular economy in agriculture in Vietnam
According to recent studies, the development of circular economy in agriculture in Vietnam is facing the following problems:
Firstly, the awareness of state management agencies, businesses and farmers about circular agriculture is incomplete. In our country, the seeds of circular economy in agriculture have existed since the early 1980s of the twentieth century, but the term “circular agriculture” has just been mentioned. Therefore, the role, benefits, nature, content, and criteria of circular agriculture are unclear, leading to a vague and incomplete understanding of the circular economy among relevant stakeholders in agriculture. This is one of the barriers to developing circular agriculture in Vietnam.
Secondly, there is no motivation to develop a circular economy in agriculture. Recently, our country’s agricultural production has been gradually shifting its focus to sustainable and organic agriculture; however, it still primarily emphasizes output through increased inputs. Therefore, agricultural production still relies mainly on resource exploitation and the use of growth stimulants, pesticides, and inorganic fertilizers, which has not created a motivation to apply a circular economy in agriculture.
Thirdly, the capacity to recycle and reuse agricultural byproducts and waste products remains limited. Currently, our country lacks a team of staff to research, apply, and transfer technology for treating waste and by-products in agriculture. In addition, since the scale of agricultural production is small, the collection and classification of agricultural waste, as well as investment in recycling technology, have not been paid attention to. Agricultural enterprises are largely limited in recycling and reuse technology as well as capital and human resources, so they are interested in recovering and reusing main by-products in the production process. Some localities have not prioritized waste management or provided technical training and guidance for production facilities. Therefore, currently only about 10% of crop by-products are reused as local fuel, 5% as industrial fuel, 3% as animal feed; more than 80% are not reused and are discharged directly into the environment or burned, causing environmental pollution (Reganold, John P., and Jonathan M. Wachter, 2016).
Fourthly, there is a lack of guidance and standardization for implementing a circular economy in agriculture. Up to now, the circular economy in the world has been applied by many countries, but in Vietnam it is still relatively new, especially in the field of agriculture. Therefore, circular economy models applied in agriculture are not complete and spontaneous. There have been no regulations or criteria for identification and evaluation, nor has there been a focal agency on this issue, while the circular economy in agriculture involves many fields. Currently, regulations related to the circular economy in general and circular agriculture in particular are scattered in different laws and decrees. Besides, funding conditions are still limited, making it very difficult to deploy and develop a circular economy in the economy in general and agriculture in particular.
Prospects for developing circular agriculture in Vietnam
Circular agriculture for Vietnam is neither new nor novel. It is not new because, circular agricultural production models have been applied in Vietnam for many years. The earliest can be mentioned as the Garden - Pond - Barn model (also known as the VAC model), the VAC combined forest model (VACR), which has been widely deployed since the 1980s. Next is the livestock model combined with biogas in the 2000s. In addition, due to natural conditions, many regions of Vietnam still apply combined crop and livestock models, such as cows with corn, rice with fish, and rice with shrimp.
It can be said that the above combined models represent a form of intensive farming, creating an overall farming system that effectively utilizes land and water resources, helping farmers achieve higher economic efficiency with low investment. At the same time, they contribute to partially reducing environmental pollution problems in livestock farming.
However, if understood in the agricultural sense of the future, the above-mentioned combined production models, often at a household scale, can only be considered a primitive level of circular agriculture. There is a lack of science and technology applied to the production process. To develop modern agriculture, circular agriculture needs to be linked with high-tech agriculture, used at the farm scale, and promote links with businesses.
Regarding the institutional environment, Vietnam does not have its own policies for circular agriculture, but some policies support the development of circular agriculture. For example, the Vietnam Sustainable Development Strategy 2011-2020; Environmental Protection Strategy to 2020, vision to 2030; Green growth strategy; Decree No. 38/2015/ND-CP of the Government: On waste and scrap management; Decision No. 16/2015/QD-TTg on recall and treatment of discarded products; or the National Strategy on Integrated Solid Waste Management 2018.
In Vietnam, the total amount of agricultural by-products is estimated to be nearly 160 million tons. Of which, more than half is post-harvest by-products from crops and from the processing of agricultural products in the farming industry; almost 40% are livestock and poultry waste from the livestock industry, the rest is by-products from the forestry and fisheries industry. This is the reason, and also the premise for developing circular agriculture. Currently, the utilization of crop residues and animal wastes is relatively low, resulting in a partial underutilization of resources, increased emissions, and environmental pollution. In order to strengthen circular system and reuse these resources, we need to incorporate very well two sub-sectors of crops and livestock, and combine national policies to create a clear policy corridor and increase income from animal wastes and crop residues in farms to reduce pollution and obtain organic agriculture towards a circular economy and sustainable agriculture. Some current practices of circular systems, such as, production of organic fertilizers from animal wastes and crop residues, incorporation of rice straw into the soil, stove gasification and carbonization for renewable energy and biochar, organic agriculture and circulated farm showing many advantages of effectively use animal wastes and crop residues for agriculture production to reduce environmental pollution, enhance soil fertility, generate clean energy and reduce synthetic fertilizers as well as reducing GHG emissions.
CONCLUSION AND RECOMMENDATIONS
Over the years, Vietnamese agriculture has always maintained a central position in ensuring national food security, providing raw materials for the processing industry and export. Developing circular agriculture will be a vital trend for sustainable agricultural development. There are some policy recommendations:
Firstly, raise awareness among state agricultural management agencies, businesses and farmers about the circular economy in agriculture. It is necessary to develop a communication strategy about the circular economy model in agriculture, including role, benefits, nature, content, criteria, implementation methods and etc. After that, promote propaganda through mass media, training programs at all levels, from high school to university, agricultural training classes, and agricultural extension programs. Depending on each subject and area, there are different appropriate measures; for example, state management agencies in charge of agriculture, and businesses visit and study the experiences of some countries or domestic companies that have successfully implemented circular agriculture; guide farmers depending on the area (plain, midland, mountainous, coastal) to choose effective models of utilizing agricultural byproducts and waste products.
Secondly, create incentives for localities, businesses, and farmers to invest in circular agriculture. Support in capital, technology, and market; guiding businesses and farmers to carry out agricultural production along the value chain in each cycle: from production, distribution consumption to recycling. Promote the implementation and replication of production models using agricultural waste to grow mushrooms, soybeans, corn, potatoes, and etc.; Encourage the expansion of organic agricultural production models, clean agriculture, and high-tech agriculture; Recommend and even ban the burning of straw in the fields, and forbid livestock facilities from discharging waste that causes pollution.
Thirdly, improve the capacity to recycle and reuse agricultural by-products and waste products. Training and fostering a workforce to research and deploy technology for processing by-products and waste products in agriculture. Invest in research and the transfer of science and technology for agricultural waste treatment, particularly in areas with large-scale cultivation and livestock operations. Advise and support (premises, capital, technology) agricultural production entities so that they focus on collecting, classifying agricultural waste and waste products as well as investing in recycling technology. Encourage localities across the country, based on existing models and their specific conditions, to develop appropriate circular economy models in agriculture. Promote links between businesses and farmers. Encourage businesses and corporations with great potential to invest in exploiting and processing agricultural by-products to create organic fertilizers and substrates; promote advanced, environmentally friendly production processes; Build and replicate models of using mixed animal feed and biological products to replace antibiotics in livestock and aquaculture.
Fourthly, build a legal corridor by integrating circular economy into Nationally Determined Contribution (NDC) is necessary. The policy should also build standards of circular economy in agriculture. To promote a circular economy in agricultural development, the State plays a crucial role in establishing a transparent, stable, and favorable legal framework to attract businesses, industry organizations, and individuals to participate. It is determined that businesses play a central role and serve as the core nucleus. The State creates a business environment through mechanisms and policies to develop clean technology, promote reuse, and recycle waste, ensuring that waste becomes a resource in both production and consumption aspects of the economy. There must be a policy to prioritize businesses investing in recycling technology for some high-value agricultural by-products.
REFERENCES
DeLong C, Cruse R, Wiener J (2015) The soil degradation paradox: compromising our resources when we need them the most. Sustainability 7(1):866–879. https://doi.org/10.3390 /su7010866
Ellen MacArthur Foundation (2016). Cities and circular economy for food. https://www.ellenmacarthurfoundation.org/publications/cities-and-circular-economy-for-food.
FAO (2016). Save and grow in practice: maize, rice, wheat: A guide to sustainable cereal production. Rome.
FAO (2021) FAO’s work on Climate Change. https://www.fao.org/climate-change/en/
FAO & ICRAF (2019). Agroforestry and tenure. Forestry Working Paper, No. 8. Rome.
Foley JA, Defries R, Asner GP, Barford C, Bonan G, Carpenter SR, Chapin FS, Coe MT, Daily GC, Gibbs HK, Helkowski JH, Holloway T, Howard EA, Kucharik CJ, Monfreda C, Patz JA, Prentice IC, Ramankutty N, Snyder PK (2005) Global consequences of land use. Science (NY) 309(5734): 570–574. https://doi.org/10.1126/science.1111772
Meemken, Eva-Marie, and Matin Qaim (2018). Organic agriculture, food security and the environment. Annual Review of Resource Economics, vol. 10: 39–63.
Ponisio, L., and others (2015). Diversification practices reduce organic to conventional yield gap. Proceedings of the Royal Society B: Biological Sciences 282 (1799).
Rahmann G, Reza AM, Bàrberi P, Boehm H, Canali S, Chander M et al (2017) Organic agriculture 3.0 is innovation with research. Org Agric 7(3):169–197. https://doi.org/10.1007 /s13165-016-0171-5
Reganold, John P., and Jonathan M. Wachter (2016). Organic agriculture in the twenty-first century. Nature Plants 2(2):1–8.
Robertson, K.L, and others (2004). Farming for ecosystem services: an ecological approach to production agriculture. Bioscience, 2014, pp. 61–65
UN (2015) Transforming our world: the 2030 Agenda for Sustainable Development. https://sdgs.un.org/2030agenda
UN (2017) World population prospects: the 2017 revision. Key findings & advance tables. Edited by United Nations, Department of Economic and Social Affairs, Population Division. United Nations. New York
UNFCC (2021) Land Use, Land-Use Change and Forestry (LULUCF). Land Use, Land-Use Change and Forestry (LULUCF) | UNFCC