有机农业对可持续发展的贡献

Nadia El-Hage Scialabba
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Organic agriculture, as defined by the Codex Alimentarius Commission, “is a holistic production management system that avoids use of synthetic fertilizers, pesticides and genetically-modified organisms, minimizes pollution of air, soil and water, and optimizes the health and productivity of interdependent communities of plants, animals and people.”</p><p>In organic agriculture, limiting external inputs necessitates adaptation to local conditions in order to harness ecosystem services and increase production efficiency. To this end, the main organic strategies include: rotations, diversification and integration of crop, livestock, tree, and fish to the extent possible in order to optimize nutrient cycling; use of local varieties and breeds in order to increase the system resilience to stress; use of biological pest control to enhance predators; and promotion of symbiotic nitrogen fixation and biomass recycling.</p><p>Organic management is associated with several positive impacts on land and water, including: increased soil fertility and thus, enhanced productivity; better soil structure that increases stability to environmental stress; better soil moisture retention and drainage, which result in 20 to 60% less irrigation requirements; less water pollution and nitrate leaching in groundwater; reduced erosion by wind, water, and overgrazing (currently, 10 million hectares of land is lost annually by unsustainable agricultural practices); and better soil carbon sequestration rates. A new meta-analysis indicates that soil organic carbon stocks were 3.5 metric tons per hectare higher in organic than in non-organic farming systems and that organic farming systems sequestered up to 450 kg more atmospheric carbon per hectare and year through CO<sub>2</sub> bound into soil organic matter.</p><p>Overall, energy use by organic farms may be reduced by one-third, as compared to conventional enterprises, due to more efficiency in biological nitrogen fixation. Existing studies report less energy use on organic farms, from 10-70% in Europe and 29-37% in the USA, with exceptions for some crops. The heart of the matter is that chemical agriculture uses 2 kcal of fossil fuel to produce 1 kcal of food energy. This low energy efficiency is compounded by higher oil prices that lead to higher farm input prices, in addition to peak oil, sooner or later. The energy issue requires more attention to paradigms such as organic agriculture in order to face future food challenges.</p><p>In line with the Intergovernmental Panel for Climate Change 4th Assessment Report recommendations for agriculture, organic management addresses climate change through inherent practices such as: crop rotations and farming system design; nutrient and manure management; livestock management, pasture and fodder supply improvement; maintenance of fertile soils and restoration of degraded lands. Requirements imposed on organic agriculture by US and EU regulations reduce greenhouse gas (GHG) emissions as follows: abstaining from N-fertilizers use reduces agricultural emissions 10%; the prohibition of intensive animal husbandry in feedlots and requirement for an adequate animal/land ratio prevents intensive methane and nitrous oxide emissions; recommended nutrient management plans result in less nitrous oxides and higher soil carbon sequestration. The International Federation of Organic Agriculture Movements (IFOAM) also recommends a prohibition on land clearing, which would avoid deforestation (which alone is responsible for 12% of global GHG emissions); generally, GHG emissions from organic agriculture are always lower than conventional agriculture systems, based on production area.</p><p>Existing life-cycle analysis (LCA) studies on greenhouse gas emissions per kg of product show that organic plant products and milk perform better than their conventional counterparts, while for organic meat and egg products, better performance is not always ensured. Most importantly, organically managed soils contain higher soil organic content (SOC) (expressed in mass%age), as well as carbon stocks (expressed as absolute masses) than non-organic soils. SOC stocks are key for assessing carbon sequestration potential and organic soils usually have deep rooting with SOC stocks up to 80-cm depth, due to grass-legume mixtures and deep-digging earthworms. Globally, the cumulative advantages of several organic practices (i.e., no use of N-fertilizers, reduced nitrous oxide emissions on farms, and soil carbon sequestration) has a GHG reduction potential from 5.1 to 6.1 GT CO<sub>2</sub>equivalents.</p><p>As to climate change adaptation, organic management takes a preventive and precautionary approach through diversification, generally adopted as a risk splitting strategy. In fact, diversified farms go through natural stages of succession that best adapt the agroecosystem to change. Rotational grazing and organic pasture management have huge potential in mitigating climate change. Spatial and temporal integration on organic farms (e.g., agroforesty, hedges, rotations, corralling) represent ecofunctional features conducive to climate-proofing of agroecosystems.</p><p>Sustainability is also about equity among and between generations. The main contribution of organic agriculture to social well-being is through avoided harm and healthy community development. Avoided harm ranges from loss of arable soil, water contamination, biodiversity erosion, GHG emissions, food scares, and pandemics associated with chemical agriculture, as well as pesticide poisoning of 3 million persons per year resulting in 220,000 deaths, let alone farmers indebtedness for inputs and suicides (e.g. 30,000 deaths in Maharastra, India, from 1997 to 2005).</p><p>With regards to health, organic food commonly contains 10-60% more healthy fatty acids, organic dairy usually has more omega-3 fatty acids, organic crops tend to have 5-90% more vitamin C and 10-50 more secondary metabolites. Organic foods generally have higher dry matter and mineral content and organic diets seem to be less associated with allergies, with records of more immunity in children and animals. Although scientific evidence is mounting but not yet established, organic diets seem to result in less cancer cell proliferation.</p><p>Organic farming appears to generate 30% more employment in rural areas and labor achieves higher returns per unit of labor input. By using local resources better, organic agriculture offers dual benefits: it facilitates smallholders access to markets and thus income generation; and relocalizes food production in market-marginalized areas, especially where the hungry and the poor reside. The economic performance of organic systems depends on: previous intensity of conventional management; organic farmers’ managerial background and skills; and the suitability of used varieties and breeds to low-input systems. Generally, organic yields are 20% less as compared to high-input systems in developed countries but could be up to 180% higher as compared to low-input systems in arid/semi-arid areas. In humid areas, rice paddy yields are equal, while the productivity of the main crop is reduced for perennials, though agroforestry provides additional goods.</p><p>Farm profitability depends on: market opportunities and input/output prices; governmental support to agricultural policy; and mostly, farmer's management abilities. Variable organic production costs are significantly lower than conventional production, ranging from 50-60% for cereals and legumes, to 20-25% for dairy cows and 10-20% for horticulture products; this is due to lower input costs on synthetic inputs, lower irrigation costs, and labor cash costs that include both family labor and hired workers. Total costs are, however, only slightly lower than conventional, as fixed costs increase due to new investments during conversion (e.g., new orchards, animal houses) and certification.</p><p>Lower production costs on organic farms in association with price premiums generally compensate for reduced yields and net returns are similar to or higher than conventional systems in both developed and developing countries. Even without premiums, organic systems may be more economically profitable and, with economy of scale, premiums are less needed since post-harvest and certification costs are bound to decrease with greater quantities.</p><p>Good governance is ensured in organic systems because transparency and traceability are provided through the organic label. Legal protection of the organic claim ensures fair competition of farmers, as well as protection of consumers and the right to choose. Compliance is ensured with clear environmental and, sometimes, social standards. The food system, from standard definition to labeling, is based on participation and necessary public-private partnerships, whereby smallholders are integrated into highly demanding markets. Last but not least, the diversity of food cultures and traditional knowledge are safeguarded by organic agriculture.</p>","PeriodicalId":100342,"journal":{"name":"Crop Management","volume":"12 1","pages":"1-3"},"PeriodicalIF":0.0000,"publicationDate":"2013-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1094/CM-2013-0429-09-PS","citationCount":"20","resultStr":"{\"title\":\"Organic Agriculture's Contribution to Sustainability\",\"authors\":\"Nadia El-Hage Scialabba\",\"doi\":\"10.1094/CM-2013-0429-09-PS\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Sustainability is about ecosystem integrity, social well-being, economic resilience, and good governance. 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To this end, the main organic strategies include: rotations, diversification and integration of crop, livestock, tree, and fish to the extent possible in order to optimize nutrient cycling; use of local varieties and breeds in order to increase the system resilience to stress; use of biological pest control to enhance predators; and promotion of symbiotic nitrogen fixation and biomass recycling.</p><p>Organic management is associated with several positive impacts on land and water, including: increased soil fertility and thus, enhanced productivity; better soil structure that increases stability to environmental stress; better soil moisture retention and drainage, which result in 20 to 60% less irrigation requirements; less water pollution and nitrate leaching in groundwater; reduced erosion by wind, water, and overgrazing (currently, 10 million hectares of land is lost annually by unsustainable agricultural practices); and better soil carbon sequestration rates. A new meta-analysis indicates that soil organic carbon stocks were 3.5 metric tons per hectare higher in organic than in non-organic farming systems and that organic farming systems sequestered up to 450 kg more atmospheric carbon per hectare and year through CO<sub>2</sub> bound into soil organic matter.</p><p>Overall, energy use by organic farms may be reduced by one-third, as compared to conventional enterprises, due to more efficiency in biological nitrogen fixation. Existing studies report less energy use on organic farms, from 10-70% in Europe and 29-37% in the USA, with exceptions for some crops. The heart of the matter is that chemical agriculture uses 2 kcal of fossil fuel to produce 1 kcal of food energy. This low energy efficiency is compounded by higher oil prices that lead to higher farm input prices, in addition to peak oil, sooner or later. The energy issue requires more attention to paradigms such as organic agriculture in order to face future food challenges.</p><p>In line with the Intergovernmental Panel for Climate Change 4th Assessment Report recommendations for agriculture, organic management addresses climate change through inherent practices such as: crop rotations and farming system design; nutrient and manure management; livestock management, pasture and fodder supply improvement; maintenance of fertile soils and restoration of degraded lands. Requirements imposed on organic agriculture by US and EU regulations reduce greenhouse gas (GHG) emissions as follows: abstaining from N-fertilizers use reduces agricultural emissions 10%; the prohibition of intensive animal husbandry in feedlots and requirement for an adequate animal/land ratio prevents intensive methane and nitrous oxide emissions; recommended nutrient management plans result in less nitrous oxides and higher soil carbon sequestration. The International Federation of Organic Agriculture Movements (IFOAM) also recommends a prohibition on land clearing, which would avoid deforestation (which alone is responsible for 12% of global GHG emissions); generally, GHG emissions from organic agriculture are always lower than conventional agriculture systems, based on production area.</p><p>Existing life-cycle analysis (LCA) studies on greenhouse gas emissions per kg of product show that organic plant products and milk perform better than their conventional counterparts, while for organic meat and egg products, better performance is not always ensured. Most importantly, organically managed soils contain higher soil organic content (SOC) (expressed in mass%age), as well as carbon stocks (expressed as absolute masses) than non-organic soils. SOC stocks are key for assessing carbon sequestration potential and organic soils usually have deep rooting with SOC stocks up to 80-cm depth, due to grass-legume mixtures and deep-digging earthworms. Globally, the cumulative advantages of several organic practices (i.e., no use of N-fertilizers, reduced nitrous oxide emissions on farms, and soil carbon sequestration) has a GHG reduction potential from 5.1 to 6.1 GT CO<sub>2</sub>equivalents.</p><p>As to climate change adaptation, organic management takes a preventive and precautionary approach through diversification, generally adopted as a risk splitting strategy. In fact, diversified farms go through natural stages of succession that best adapt the agroecosystem to change. Rotational grazing and organic pasture management have huge potential in mitigating climate change. Spatial and temporal integration on organic farms (e.g., agroforesty, hedges, rotations, corralling) represent ecofunctional features conducive to climate-proofing of agroecosystems.</p><p>Sustainability is also about equity among and between generations. The main contribution of organic agriculture to social well-being is through avoided harm and healthy community development. Avoided harm ranges from loss of arable soil, water contamination, biodiversity erosion, GHG emissions, food scares, and pandemics associated with chemical agriculture, as well as pesticide poisoning of 3 million persons per year resulting in 220,000 deaths, let alone farmers indebtedness for inputs and suicides (e.g. 30,000 deaths in Maharastra, India, from 1997 to 2005).</p><p>With regards to health, organic food commonly contains 10-60% more healthy fatty acids, organic dairy usually has more omega-3 fatty acids, organic crops tend to have 5-90% more vitamin C and 10-50 more secondary metabolites. Organic foods generally have higher dry matter and mineral content and organic diets seem to be less associated with allergies, with records of more immunity in children and animals. Although scientific evidence is mounting but not yet established, organic diets seem to result in less cancer cell proliferation.</p><p>Organic farming appears to generate 30% more employment in rural areas and labor achieves higher returns per unit of labor input. By using local resources better, organic agriculture offers dual benefits: it facilitates smallholders access to markets and thus income generation; and relocalizes food production in market-marginalized areas, especially where the hungry and the poor reside. The economic performance of organic systems depends on: previous intensity of conventional management; organic farmers’ managerial background and skills; and the suitability of used varieties and breeds to low-input systems. 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引用次数: 20

摘要

可持续性涉及生态系统完整性、社会福祉、经济复原力和良好治理。根据目前的知识和发展状况,有机农业如何对这些可持续性维度做出贡献?可持续性首先被等同于环境的健全,以确保继续提供商品和服务,为今世后代。根据食品法典委员会的定义,有机农业“是一种全面的生产管理系统,它避免使用合成肥料、农药和转基因生物,最大限度地减少空气、土壤和水的污染,并使相互依存的植物、动物和人类社区的健康和生产力达到最佳状态。”在有机农业中,限制外部投入需要适应当地条件,以便利用生态系统服务并提高生产效率。为此,主要的有机策略包括:作物、牲畜、树木和鱼类尽可能轮作、多样化和一体化,以优化养分循环;使用当地品种和品种,以提高系统的抗压力能力;利用生物防治病虫害,加强捕食者的能力;促进共生固氮和生物质循环利用。有机管理对土地和水有若干积极影响,包括:提高土壤肥力,从而提高生产力;更好的土壤结构,增加对环境应力的稳定性;更好的土壤保持水分和排水,从而减少20%至60%的灌溉需求;水体污染少,地下水硝酸盐浸出少;减少风、水和过度放牧造成的侵蚀(目前,每年有1000万公顷土地因不可持续的农业做法而流失);以及更好的土壤固碳率。一项新的荟萃分析表明,有机农业系统每公顷土壤有机碳储量比非有机农业系统高3.5公吨,有机农业系统每公顷和每年通过将二氧化碳结合到土壤有机质中,多吸收450公斤的大气碳。总体而言,由于生物固氮效率更高,与传统企业相比,有机农场的能源消耗可能减少三分之一。现有的研究报告显示,有机农场的能源消耗更少,在欧洲为10-70%,在美国为29-37%,但某些作物除外。问题的核心是化学农业使用2千卡的化石燃料来生产1千卡的食物能量。这种低能源效率加上高油价,导致农业投入价格上涨,加上石油峰值,迟早会出现。为了应对未来的粮食挑战,能源问题需要更多地关注有机农业等范例。根据政府间气候变化专门委员会第四次评估报告对农业的建议,有机管理通过诸如作物轮作和耕作系统设计等固有做法来应对气候变化;养分和粪肥管理;牲畜管理、牧场和饲料供应改善;保持肥沃土壤和恢复退化土地。美国和欧盟法规对有机农业的要求减少了温室气体(GHG)排放:不使用氮肥可减少10%的农业排放;禁止在饲养场集约化畜牧业和规定适当的动物/土地比例,可防止大量排放甲烷和一氧化二氮;推荐的养分管理计划减少了氮氧化物,提高了土壤碳固存。国际有机农业运动联合会(IFOAM)也建议禁止开垦土地,以避免森林砍伐(仅森林砍伐就占全球温室气体排放量的12%);一般来说,有机农业的温室气体排放量总是低于传统农业系统,基于生产面积。现有的生命周期分析(LCA)对每公斤产品温室气体排放量的研究表明,有机植物产品和牛奶的性能优于传统产品,而有机肉和蛋产品的性能并不总是保证更好。最重要的是,有机管理的土壤比非有机土壤含有更高的土壤有机含量(以质量%年龄表示)和碳储量(以绝对质量表示)。有机土壤的有机碳储量是评估固碳潜力的关键,由于草-豆科植物混合物和深挖蚯蚓的作用,有机土壤通常具有深生根,有机碳储量可达80厘米深。在全球范围内,几种有机做法(即不使用氮肥、减少农场一氧化二氮排放和土壤碳固存)的累积优势使温室气体减排潜力从5.1亿吨二氧化碳当量减少到6.1亿吨二氧化碳当量。 在适应气候变化方面,有机管理通过多样化采取预防和预防的方法,一般采用风险分散策略。事实上,多样化农场经历了自然演替阶段,这是最能使农业生态系统适应变化的阶段。轮牧和有机牧场管理在减缓气候变化方面具有巨大潜力。有机农场的空间和时间整合(如农林业、树篱、轮作、围栏)代表了有利于农业生态系统抗气候的生态功能特征。可持续发展还涉及代与代之间的公平。有机农业对社会福祉的主要贡献是通过避免伤害和健康的社区发展。可避免的危害包括可耕地流失、水污染、生物多样性侵蚀、温室气体排放、粮食恐慌和与化学农业有关的流行病,以及每年300万人的农药中毒,造成22万人死亡,更不用说农民因投入物而负债和自杀(例如,1997年至2005年,印度马哈拉施特拉邦有3万人死亡)。在健康方面,有机食品通常含有10-60%以上的健康脂肪酸,有机乳制品通常含有更多的omega-3脂肪酸,有机作物往往含有5-90%以上的维生素C和10- 50%以上的次级代谢物。有机食品通常有更高的干物质和矿物质含量,有机饮食似乎与过敏的关系更小,有记录显示儿童和动物的免疫力更高。虽然科学证据越来越多,但尚未确定,有机饮食似乎能减少癌细胞的增殖。有机农业似乎在农村地区创造了30%以上的就业机会,劳动力每单位劳动投入的回报更高。通过更好地利用当地资源,有机农业提供了双重好处:它有助于小农进入市场,从而产生收入;将粮食生产重新定位到市场边缘地区,特别是饥饿和贫困人口居住的地区。有机系统的经济效益取决于:以前的常规管理强度;有机农民的管理背景和技能;以及所使用品种和品种对低投入系统的适用性。一般来说,与发达国家的高投入系统相比,有机产量低20%,但在干旱/半干旱地区,与低投入系统相比,有机产量可高出180%。在潮湿地区,水稻产量相等,而多年生作物的主要作物生产力降低,尽管农林业提供了额外的产品。农场盈利能力取决于:市场机会和投入/产出价格;政府对农业政策的支持;最重要的是农民的管理能力。可变有机生产成本明显低于传统生产,从谷物和豆类的50-60%到奶牛的20-25%和园艺产品的10-20%不等;这是由于合成投入的投入成本较低,灌溉成本较低,以及包括家庭劳动力和雇佣工人在内的劳动力现金成本较低。但是,总费用只比传统方法略低,因为在转换期间(例如,新果园、畜舍)和核证期间的新投资增加了固定费用。在发达国家和发展中国家,有机农场较低的生产成本与价格溢价相关联,通常补偿了产量的减少,净收益与传统系统相似或高于传统系统。即使没有保费,有机系统也可能更具经济效益,而且随着规模经济的发展,保费的需求也会减少,因为收获后和认证成本必然会随着数量的增加而降低。良好的管理在有机系统中得到保证,因为通过有机标签提供了透明度和可追溯性。对有机主张的法律保护既保障了农民的公平竞争,又保护了消费者的选择权。遵循明确的环境标准,有时甚至是社会标准。食品体系,从标准定义到标签,都是建立在参与和必要的公私伙伴关系的基础上的,通过这种伙伴关系,小农被纳入了要求很高的市场。最后但并非最不重要的是,有机农业保护了饮食文化和传统知识的多样性。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Organic Agriculture's Contribution to Sustainability

Sustainability is about ecosystem integrity, social well-being, economic resilience, and good governance. According to the current state of knowledge and development, how does organic agriculture contribute to each of these sustainability dimensions?

Sustainability has first been equated with environmental soundness in order to ensure the continued provision of goods and services to present and future generations. Organic agriculture, as defined by the Codex Alimentarius Commission, “is a holistic production management system that avoids use of synthetic fertilizers, pesticides and genetically-modified organisms, minimizes pollution of air, soil and water, and optimizes the health and productivity of interdependent communities of plants, animals and people.”

In organic agriculture, limiting external inputs necessitates adaptation to local conditions in order to harness ecosystem services and increase production efficiency. To this end, the main organic strategies include: rotations, diversification and integration of crop, livestock, tree, and fish to the extent possible in order to optimize nutrient cycling; use of local varieties and breeds in order to increase the system resilience to stress; use of biological pest control to enhance predators; and promotion of symbiotic nitrogen fixation and biomass recycling.

Organic management is associated with several positive impacts on land and water, including: increased soil fertility and thus, enhanced productivity; better soil structure that increases stability to environmental stress; better soil moisture retention and drainage, which result in 20 to 60% less irrigation requirements; less water pollution and nitrate leaching in groundwater; reduced erosion by wind, water, and overgrazing (currently, 10 million hectares of land is lost annually by unsustainable agricultural practices); and better soil carbon sequestration rates. A new meta-analysis indicates that soil organic carbon stocks were 3.5 metric tons per hectare higher in organic than in non-organic farming systems and that organic farming systems sequestered up to 450 kg more atmospheric carbon per hectare and year through CO2 bound into soil organic matter.

Overall, energy use by organic farms may be reduced by one-third, as compared to conventional enterprises, due to more efficiency in biological nitrogen fixation. Existing studies report less energy use on organic farms, from 10-70% in Europe and 29-37% in the USA, with exceptions for some crops. The heart of the matter is that chemical agriculture uses 2 kcal of fossil fuel to produce 1 kcal of food energy. This low energy efficiency is compounded by higher oil prices that lead to higher farm input prices, in addition to peak oil, sooner or later. The energy issue requires more attention to paradigms such as organic agriculture in order to face future food challenges.

In line with the Intergovernmental Panel for Climate Change 4th Assessment Report recommendations for agriculture, organic management addresses climate change through inherent practices such as: crop rotations and farming system design; nutrient and manure management; livestock management, pasture and fodder supply improvement; maintenance of fertile soils and restoration of degraded lands. Requirements imposed on organic agriculture by US and EU regulations reduce greenhouse gas (GHG) emissions as follows: abstaining from N-fertilizers use reduces agricultural emissions 10%; the prohibition of intensive animal husbandry in feedlots and requirement for an adequate animal/land ratio prevents intensive methane and nitrous oxide emissions; recommended nutrient management plans result in less nitrous oxides and higher soil carbon sequestration. The International Federation of Organic Agriculture Movements (IFOAM) also recommends a prohibition on land clearing, which would avoid deforestation (which alone is responsible for 12% of global GHG emissions); generally, GHG emissions from organic agriculture are always lower than conventional agriculture systems, based on production area.

Existing life-cycle analysis (LCA) studies on greenhouse gas emissions per kg of product show that organic plant products and milk perform better than their conventional counterparts, while for organic meat and egg products, better performance is not always ensured. Most importantly, organically managed soils contain higher soil organic content (SOC) (expressed in mass%age), as well as carbon stocks (expressed as absolute masses) than non-organic soils. SOC stocks are key for assessing carbon sequestration potential and organic soils usually have deep rooting with SOC stocks up to 80-cm depth, due to grass-legume mixtures and deep-digging earthworms. Globally, the cumulative advantages of several organic practices (i.e., no use of N-fertilizers, reduced nitrous oxide emissions on farms, and soil carbon sequestration) has a GHG reduction potential from 5.1 to 6.1 GT CO2equivalents.

As to climate change adaptation, organic management takes a preventive and precautionary approach through diversification, generally adopted as a risk splitting strategy. In fact, diversified farms go through natural stages of succession that best adapt the agroecosystem to change. Rotational grazing and organic pasture management have huge potential in mitigating climate change. Spatial and temporal integration on organic farms (e.g., agroforesty, hedges, rotations, corralling) represent ecofunctional features conducive to climate-proofing of agroecosystems.

Sustainability is also about equity among and between generations. The main contribution of organic agriculture to social well-being is through avoided harm and healthy community development. Avoided harm ranges from loss of arable soil, water contamination, biodiversity erosion, GHG emissions, food scares, and pandemics associated with chemical agriculture, as well as pesticide poisoning of 3 million persons per year resulting in 220,000 deaths, let alone farmers indebtedness for inputs and suicides (e.g. 30,000 deaths in Maharastra, India, from 1997 to 2005).

With regards to health, organic food commonly contains 10-60% more healthy fatty acids, organic dairy usually has more omega-3 fatty acids, organic crops tend to have 5-90% more vitamin C and 10-50 more secondary metabolites. Organic foods generally have higher dry matter and mineral content and organic diets seem to be less associated with allergies, with records of more immunity in children and animals. Although scientific evidence is mounting but not yet established, organic diets seem to result in less cancer cell proliferation.

Organic farming appears to generate 30% more employment in rural areas and labor achieves higher returns per unit of labor input. By using local resources better, organic agriculture offers dual benefits: it facilitates smallholders access to markets and thus income generation; and relocalizes food production in market-marginalized areas, especially where the hungry and the poor reside. The economic performance of organic systems depends on: previous intensity of conventional management; organic farmers’ managerial background and skills; and the suitability of used varieties and breeds to low-input systems. Generally, organic yields are 20% less as compared to high-input systems in developed countries but could be up to 180% higher as compared to low-input systems in arid/semi-arid areas. In humid areas, rice paddy yields are equal, while the productivity of the main crop is reduced for perennials, though agroforestry provides additional goods.

Farm profitability depends on: market opportunities and input/output prices; governmental support to agricultural policy; and mostly, farmer's management abilities. Variable organic production costs are significantly lower than conventional production, ranging from 50-60% for cereals and legumes, to 20-25% for dairy cows and 10-20% for horticulture products; this is due to lower input costs on synthetic inputs, lower irrigation costs, and labor cash costs that include both family labor and hired workers. Total costs are, however, only slightly lower than conventional, as fixed costs increase due to new investments during conversion (e.g., new orchards, animal houses) and certification.

Lower production costs on organic farms in association with price premiums generally compensate for reduced yields and net returns are similar to or higher than conventional systems in both developed and developing countries. Even without premiums, organic systems may be more economically profitable and, with economy of scale, premiums are less needed since post-harvest and certification costs are bound to decrease with greater quantities.

Good governance is ensured in organic systems because transparency and traceability are provided through the organic label. Legal protection of the organic claim ensures fair competition of farmers, as well as protection of consumers and the right to choose. Compliance is ensured with clear environmental and, sometimes, social standards. The food system, from standard definition to labeling, is based on participation and necessary public-private partnerships, whereby smallholders are integrated into highly demanding markets. Last but not least, the diversity of food cultures and traditional knowledge are safeguarded by organic agriculture.

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