Carbon footprint of smallholder farms in Central Madagascar: The integration of agroecological practices

Annals of Agricultural Sciences

This study aimed at estimating carbon footprint (CF) and assessing mitigation options for selected tropical crops using excel-based models, parameterized with data collected through closed-ended questions questionnaires, combined with a reference trial (RT). Most of the estimates using structured interviews were similar to those measured in the RT and the literature. Total average emission intensities ranged from 24 to 290 kg CO 2 eq•Mg −1 , where the extreme values corresponded to cassava in the RT (24 kg CO 2 eq•Mg −1) and maize in interviewed farmers in Barranca province (290 kg CO 2 eq•Mg −1). Overall, fertilizer production and application contributed to 77% of total greenhouse gas (GHG). Transportation generated emissions comparable to field estimates. Farm emissions can be reduced in 17 to 27% with incorporation of mitigation practices. The methodology used in this study constitute a useful and easily applicable tool to assess ex-ante the impact of policies and decisions on CF under farm conditions. It can also be used by different stakeholders for different purposes; including but not limited to: label products offered in the market with GHG emission estimates, make decisions to regulate the emissions in the agricultural sector, and to enable farmers to negotiate prices and incentives for environmental preservation with quantitative information.

CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition, and Natural Resources, 2012

According to the Intergovernmental Panel on Climate Change (IPCC), agriculture is responsible for 10-12% of total global anthropogenic emissions and almost a quarter of the continuing increase of greenhouse gas (GHG) emissions. Not all forms of agriculture, however, have equivalent impacts on global warming. Industrial agriculture contributes significantly to global warming, representing a large majority of total agriculture-related GHG emissions. Alternatively, ecologically based methods for agricultural production, predominantly used on small-scale farms, are far less energy-consumptive and release fewer GHGs than industrial agricultural production. Besides generating fewer direct emissions, agro-ecological management techniques have the potential to sequester more GHGs than industrial agriculture. Here, we review the literature on the contributions of agriculture to climate change and show the extent of GHG contributions from the industrial agricultural system and the potential of agro-ecological smallholder agriculture to help reduce GHG emissions. These reductions are achieved in three broad areas when compared with the industrial agricultural system: (1) a decrease in materials used and fluxes involved in the release of GHGs based on agricultural crop management choices; (2) a decrease in fluxes involved in livestock production and pasture management; and (3) a reduction in the transportation of agricultural inputs, outputs and products through an increased emphasis on local food systems. Although there are a number of barriers and challenges towards adopting small-scale agroecological methods on the large scale, appropriate incentives can lead to incremental steps towards agro-ecological management that may be able to reduce and mitigate GHG emissions from the agricultural sector.

Environmental Pollution, 2007

Abstract Agriculture is a source for three primary greenhouse gases (GHGs): CO 2 , CH 4 , and N 2 O. It can also be a sink for CO 2 through C sequestration into biomass products and soil organic matter. We summarized the literature on GHG emissions and C sequestration, providing a perspective on how agriculture can reduce its GHG burden and how it can help to mitigate GHG emissions through conservation measures. Impacts of agricultural practices and systems on GHG emission are reviewed and potential trade-offs among potential mitigation options are discussed. Conservation practices that help prevent soil erosion, may also sequester soil C and enhance CH 4 consumption. Managing N to match crop needs can reduce N 2 O emission and avoid adverse impacts on water quality. Manipulating animal diet and manure management can reduce CH 4 and N 2 O emission from animal agriculture. All segments of agriculture have management options that can reduce agriculture's environmental footprint. Published by Elsevier Ltd.

Environmental Research Letters, 2014

The IPCC has compiled the best available scientific methods into published guidelines for estimating greenhouse gas emissions and emission removals from the land-use sector. In order to evaluate existing GHG quantification tools to comprehensively quantify GHG emissions and removals in smallholder conditions, farm scale quantification was tested with farm data from Western Kenya. After conducting a cluster analysis to identify different farm typologies GHG quantification was exercised using the VCS SALM methodology complemented with IPCC livestock emission factors and the cool farm tool. The emission profiles of four farm clusters representing the baseline conditions in the year 2009 are compared with 2011 where farmers adopted sustainable land management practices (SALM). The results demonstrate the variation in both the magnitude of the estimated GHG emissions per ha between different smallholder farm typologies and the emissions estimated by applying two different accounting tools. The farm scale quantification further shows that the adoption of SALM has a significant impact on emission reduction and removals and the mitigation benefits range between 4 and 6.5 tCO 2 ha −1 yr −1 with significantly different mitigation benefits depending on typologies of the crop-livestock systems, their different agricultural practices, as well as adoption rates of improved practices. However, the inherent uncertainty related to the emission factors applied by accounting tools has substantial implications for reported agricultural emissions. With regard to uncertainty related to activity data, the assessment confirms the high variability within different farm types as well as between different parameters surveyed to comprehensively quantify GHG emissions within smallholder farms.

2008

Few field studies examine greenhouse gas (GHG) emissions from African agricultural systems, resulting in high uncertainty for national inventories. This lack of data is particularly noticeable in smallholder farms in sub-Saharan Africa, where low inputs are often correlated with low yields, often resulting in food insecurity as well. We provide the most comprehensive study in Africa to date, examining annual soil CO 2 , CH 4 and N 2 O emissions from 59 smallholder plots across different vegetation types, field types and land classes in western Kenya. The study area consists of a lowland area (approximately 1200 m a.s.l.) rising approximately 600 m to a highland plateau. Cumulative annual fluxes ranged from 2.8 to 15.0 Mg CO 2-C ha −1 , −6.0 to 2.4 kg CH 4-C ha −1 and −0.1 to 1.8 kg N 2 ON ha −1. Management intensity of the plots did not result in differences in annual GHG fluxes measured (P = 0.46, 0.14 and 0.67 for CO 2 , CH 4 and N 2 O respectively). The similar emissions were likely related to low fertilizer input rates (≤ 20 kg N ha −1). Grazing plots had the highest CO 2 fluxes (P = 0.005), treed plots (plantations) were a larger CH 4 sink than grazing plots (P = 0.05), while soil N 2 O emissions were similar across vegetation types (P = 0.59). This study is likely representative for low fertilizer input, smallholder systems across sub-Saharan Africa, providing critical data for estimating regional or continental GHG inventories. Low crop yields, likely due to low fertilization inputs, resulted in high (up to 67 g N 2 ON kg −1 aboveground N uptake) yield-scaled emissions. Improvement of crop production through better water and nutrient management might therefore be an important tool in increasing food security in the region while reducing the climate footprint per unit of food produced.

2020

With the unprecedented increase in natural resource exploitation and uncontrolled population rise, reaching to an irreversible point has led to a major global issue in form of Climate change. Greenhouse gases (GHGs) blamable for the adverse climatic conditions are emitted by a variety of natural as well as anthropogenic sources. Agricultural practices in the course of crop production, food processing and product marketing all generate GHG, contributing to the global climate change. With the rising population, the food demand also increases thus, increasing the proportion of GHG emissions from agricultural sector. Carbon footprint of agriculture in general terms is the sum total of GHGs (in terms of carbon equivalent (C-eq)) emanated during the processes in agrarian sector. Carbon footprints can be estimated by summing the of emissions from (1) the decomposition of crop straw and roots; (2) the manufacture of N and P fertilizers and their rates of application; (3) the production of h...

The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO.

Biology

Global attention to climate change issues, especially air temperature changes, has drastically increased over the last half-century. Along with population growth, greater surface temperature, and higher greenhouse gas (GHG) emissions, there are growing concerns for ecosystem sustainability and other human existence on earth. The contribution of agriculture to GHG emissions indicates a level of 18% of total GHGs, mainly from carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Thus, minimizing the effects of climate change by reducing GHG emissions is crucial and can be accomplished by truly understanding the carbon footprint (CF) phenomenon. Therefore, the purposes of this study were to improve understanding of CF alteration due to agricultural management and fertility practices. CF is a popular concept in agro-environmental sciences due to its role in the environmental impact assessments related to alternative solutions and global climate change. Soil moisture content, soi...

2003

Relationships between the greenhouse effect and agricultural activity are usually and firstly considered in terms of the impact of climate change on agriculture. But in reverse, farmers and herders may react to a climate policy imposing a carbon price to GHG-emitting activities, and possibly contribute to the emissions mitigation as well as to carbon sequestration. The degree of efficiency of the reactions will vary across regions of the world and across activities. A methodology considering risk associated with technology changes is proposed for estimating and accounting these reactions under production and resource constraints. For a business-as-usual scenario quantified by the integrated assessment model Image, decisions concerning land-use and alternative practices are modeled. Results indicate that main agricultural activities provide little room for manoeuvre for emissions mitigation.

Journal of Agricultural Extension Management (JAEM), 2021

According to the World Resources Institute Climate Analysis Indicators Tool (WRI CAIT), India's total Green House Gas (GHG) emissions in 2014 were 3,202 million metric tons of carbon dioxide equivalent (MtCO2e), totalling 6.55 per cent of global GHG emissions. India is the world's fourth-biggest emitter of carbon dioxide after China, the US and the EU. In India, about 68.7 per cent of GHG emissions come from the energy sector, followed by agriculture (19.6%), industrial processes (6%), land-use change and forestry (3.8%), and waste (1.9%). The global technical GHG mitigation potential from agriculture is estimated to be 5.5-6.0 Gt CO2-eq/year, by 2030. This can be achieved by the adoption of the best available management practices related to sustainable land use, good agronomic practices, soil and water management practices, agroforestry, etc. In the COP26 summit held at Glasgow, 2021, India has pledged to adopt a net-zero emissions target by 2070. In this context, academia and research organizations are undertaking research on carbon sequestration and GHG emission mitigation. The results indicate that there are huge opportunities for investment through carbon financing in agriculture to upscale the good practices to reduce the atmospheric greenhouse gas emission through carbon sequestration. This review paper elucidates the important Climate smart Agricultural (CSA) technologies and practices that help in the sequestration of carbon and reducing the emission of GHGs.

Sri Lanka is a developing country whose agricultural contribution to the economic sector is 11 per cent, and Greenhouse gas emission from the agricultural sector is 25.1 per cent. In reducing GHG emissions, it is essential to consider maintaining fertile soil and restoring degraded land. As a developing country, it is complicated to implement some of the agricultural sector's advanced techniques. But this article is beneficial to understand simple ways to reduce GHG emissions in the agricultural sector. Adaptation to climate change is also an important part to identify the available GHG emitting sources.

2012

Agriculture and land use change are responsible for one third of global greenhouse gas (GHG) emissions. These emissions have risen steadily during the 20 th century and pressures to increase food production to support growing human populations threaten to increase emissions still further, as climate change induced by the accumulation of GHGs threatens the sustainability of agricultural production. There are, however, opportunities to mitigate emissions through modifications to agricultural management that involve more efficient use of inputs and promotion of carbon sequestration. Management activities need to be adapted to take account of the variability in climates and soils, and patterns of emissions. There also need to be improvements to current methods of compiling inventories of GHG emissions to ensure that they accurately reflect actual emissions and management changes.

Is low greenhouse gas emission (GHG) agriculture possible? Is it, in fact, desirable? In seeking answers to these two basic but extremely relevant questions, this study examines current farming practices, and incorporates scientific databases from longterm field experiments as case studies for low GHG agriculture. Further, the study examines the changes that will be needed for low greenhouse gas agriculture systems to become a reality. It also elucidates the adaptive capacity of agro-ecological farming system approaches, using organic system case studies from the scientific literature. Each year, agriculture emits 10 to 12 percent of the total estimated GHG emissions, some 5.1 to 6.1 Gt CO2 equivalents per year. Smith, et al. (2007) and Bellarby, et al. (2008) have proposed mitigation options for GHG emissions, finding that both farmers and policymakers will face challenges from the GHG-related changes needed in agriculture. Areas for improvement include increased use of no-till cro...

Of the 26 Bt of CO2 loaded into the atmosphere yearly, 4 Bt is the contribution of agriculture and land clearing alone. Agriculture contributes to carbon dioxide-greenhouse gas (CO2-GHG) emission into the atmosphere in at least three ways. One, as soils are eroded, the sequestered soil organic C are released as CO2 to the atmosphere; two, monocropping results in bare soil and CO2 sequestration via plant photosynthesis in a monoculture is considerably lower than that in a forest ecosystem; and three, adoption of fossil fuel-based inputs agriculture coupled with intensive postharvest handling and distribution sums up to a significant amount of CO2 emission into the atmosphere. Some ecological agriculture practices are characterized as to their CO2-GHG soil-sequestering and emission-reducing potentials. Also, the potentials of each of these ecological agriculture practices if adopted or practiced in the Philippine landscape are evaluated. On a yearly basis, the estimates show that green manuring can reduce up to 9.12 Mt CO2, for in-situ composting or crop biomass recycling (no burning of residues) at 11.66 Mt CO2, and 12.85 Mt CO2 for tree-integration in the agricultural landscape or a total of 33.61Mt CO2. The CO2-GHG contribution of agriculture can be significantly reduced. This could be done by adopting ecological agriculture practices such as green manuring, mulching, composting, and tree integration in the agricultural landscape. Also, reduced tillage and no burning of crop residues are practices that can also contribute in the reduction of CO2-GHG emission into the atmosphere. To reduce significantly the associated CO2-GHG emissions from food systems, it is necessary to pursue localized, small-scale and family-based food production schemes. Large-scale and highly mechanized agriculture requires tremendous amounts of energy in transporting, processing, storing and distributing the products. On the consumption side, eating food lower in the food chain (less animal protein) and consuming freshly gathered rather than refrigerated and processed foods can significantly reduce GHG load in the atmosphere. A food systems audit to precisely estimate the CO2-GHG emissions from field level production and up to the time food is consumed is recommended.