Appendix A: Agricultural/Forestry management practices
Agroforestry: Agroforestry is a land management approach that combines the production of trees with other crops and/or livestock. Trees have high adaptive capacity because they are deep rooted and have large reserves of water and nutrients, and are less susceptible than annual crops to inter-annual variability or short-lived extreme events like droughts or floods. Additionally, trees improve soil quality and fertility by contributing to water retention and by reducing water stress during low rainfall years, and also have higher evapotranspiration rates than row crops or pastures and can thus pump excess water out of the soil. Trees can also reduce the impacts of weather extremes such as droughts or torrential rain and can stabilize the soil against landslides and raise infiltration rates
Biodiversity considerations: Enhancing agricultural biodiversity has significant potential to mitigate the impacts of greenhouse gases by increasing soil biodiversity to build soil organic matter, capturing carbon; using diverse leguminous crops to fix nitrogen in the soil, reducing the need for chemical fertilizers; introducing perennial crops to store carbon below ground; and planting temporary vegetative cover between successive crops to reduce nitrous oxide emissions by extracting unused nitrogen.
Change in the topography or landscapes: The use of hedges, vegetative buffer strips and other farm landscaping practices can have an enormous impact on adaptation to drought, heavy rains and winds. A change in topography can occur, for example, through the use of terraces which facilitate adaptation to climate change by optimizing water use.
Composting: The application of compost increases the amount of carbon sequestered in soils. The addition of Nitrogen reduces agricultural energy demand as a result of the increased infiltration and storage capacity of soils, thus reducing irrigation needs. The application of compost reduces the need for greenhouse gas (GHG) producing fertilizer, pesticides and herbicides.
Crop diversity: The use of germplasm (genes) of crops, forages and wild relatives that have evolved in other parts of the world, which are under similar climatic conditions to those in areas currently under stress from climate change.
Contour farming: Reduces erosion and carbon mineralization
Crop rotation: Better nutrient management through crop rotation can decrease nitrogen fertilizer use, substantially lowering related GHG emissions.
Diversifying farmer income: Many producers are including more livestock in their operations to make use of increased forage production and to add value on the farm. Livelihoods diversification into off-farm activities has the potential to reduce vulnerability to climate change impacts by reducing livelihood dependence upon farming activities. Increasing farmer resilience could ensure that the supply of agricultural inputs required by companies in the agricultural sector can be maintained over time.
Efficient equipment use: Equipment or machinery operated on farms or forest units; such as mobile
machinery (e.g., harvesters), stationary equipment (e.g., boilers), and refrigeration and air-conditioning equipment are net sources of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), or fluorinated gases (e.g. HFCs and PFCs). When equipment and machines are used efficiently it contributes to reduce the overall greenhouse gas emissions.
Enhanced forest regeneration practices: Practices that may improve or accelerate forest regeneration, e.g., planting seeds or seedlings of fast-growth species.
Fertilizer management: Fertilizer type, application rate, timing and placement have been shown to influence the amount of nitrous oxide released to the atmosphere from some soils in some years. Improved fertilizer efficiency will also reduce the amount of excess nitrogen fertilizer that can be lost to the atmosphere or to surface or groundwater.
Fire control: A series of measures can be taken to reduce the risk of large forest fires, e.g., prescribed burning, grazing, vegetation cutting, sustainable forest management, fences and fire patrol. These measures reduce the fuel loading and/or ensure fires are controlled in time.
Equipment maintenance and calibration: Ensures reliability and accuracy of data.
Governmental or institutional policies and programs: Government programs and policies, such as tax credits, research support, trade controls and crop insurance regulations, significantly influence agricultural practices. Programs and policies may act to either promote or hinder adaptation to climate change.
Integrated pest management: Integrated Pest Management (IPM) is an effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices. IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods, is used to manage pest damage. Consequently, carbon emissions from pesticide use can be reduced.
Knowledge sharing: Monitoring climate change, forecasting impacts and using early warning systems to disseminate data to a range of stakeholders from the national to the local level are all vital components to successful long-term adaptation planning and implementation. Sharing of best practice in agriculture is an important component of this practice.
Land use change: One of the most effective methods of reducing emissions is to allow or encourage the reversion of cropland to another land cover, typically one similar to the native vegetation. The conversion can occur over the entire land area (‘set-asides’) or in localized spots such as grassed waterways or field margin. Such land cover change often increases storage of carbon; for example, converting arable cropland to grassland typically results in the gain of soil carbon owing to lower soil disturbance and reduced carbon removal in harvested products. Compared to cultivated lands, grasslands may also have reduced nitrous oxide emissions from lower nitrogen inputs and higher rates of methane oxidation.
Additionally, reforestation and afforestation initiatives can increase the amount of biomass in a given area of land, thereby sequestering carbon in plant material.
Livestock management: Livestock, predominantly ruminants such as cattle and sheep, are significant sources of methane emissions, accounting for approximately 18% of global anthropogenic emissions of this gas (Smith et.al.2008). The methane is produced primarily by enteric fermentation and voided by belching. Practices for reducing methane emissions from this source fall into three general categories: improved feeding practices, use of specific agents or dietary additives, and longer-term management changes and animal breeding. There are also anti-methogen vaccines available.
Adaptations in field-based livestock include additional care to continuously match stock rates with pasture production, altered rotation of pastures, modification of times of grazing, and timing of reproduction, alteration of forage and animal species/breeds, altered integration within mixed livestock/crop systems including using adapted forage crops, reassessing fertilizer applications, care to ensure adequate water supplies, and use of supplementary feeds and concentrates. Other adaptation methods include adjusting shading and air conditioning, and the use of sprinklers to cool livestock during excessive summer heat.
Low carbon energy use: For example, the installation of on-site renewable energy systems for electricity.
Low tillage and residue management: Since soil disturbance tends to stimulate soil carbon losses through enhanced decomposition and erosion, reduced or no-till agriculture often results in soil carbon gain. Systems that retain crop residues also tend to increase soil carbon because these residues are the precursors for soil organic matter, the main store of carbon in the soil.
Low tillage or increases soil organic matter. Soil organic matter improves and stabilizes the soil structure so that the soils can absorb higher amounts of water. Soil organic matter also improves the water absorption capacity of the soil for during extended drought. Additionally, a no- or low-tilled soil conserves the structure of soil for fauna and related macrospores (earthworms, termites and root channels) to serve as drainage channels for excess water.
Manure management: Animal manures can release significant amounts of nitrous oxide and methane during storage, but the magnitude of these emissions varies. Methane emissions from manure stored in lagoons or tanks can be reduced by cooling or covering the sources, or by capturing the methane emitted. The manures can also be digested anaerobically to maximize retrieval of methane as an energy source. Storing and handling the manures in solid rather than liquid form can suppress methane emissions
Organic farming: Agriculture can make a significant contribution to mitigating climate change by taking carbon out of the air and sequestering it in the soil. The soil carbon benefit of organic farming results from the fact that the system is based on inputs of organic matter to the soil and the decomposition of this by soil microbial activity for releasing nutrients for crop production, instead of using inorganic fertilizers. This process at the same time produces humus (stable soil carbon) and thereby raises the soil’s carbon levels. As well, there is evidence that organic farming can have advantages in drought-conditions, such as higher yields compared to non-organic systems, because of the higher water-holding capacity of soils under organic management.
Practices to increase wood production and forest productivity: One of the most effective ways to sequestering carbon from the atmosphere is through carbon fixation in wood. Thus, applying techniques that promote high wood yield and productivity may be an effective mitigation strategy.
Permanent soil cover (including cover crops): The maintenance of permanent soil cover through crops, crop residues or cover crops increases soil organic matter Surface mulch cover also acts to protect soil from excess temperatures and evaporation losses and can reduce crop water requirements by 30% (FAO, 2007).
Pest, disease and weed management practices: The introduction of new cultivated species and improved varieties of crop is a technology aimed at enhancing plant productivity, quality, health and nutritional value and/or building crop resilience to diseases, pest organisms and environmental stresses. Crop diversification refers to the addition of new crops or cropping systems to agricultural production on a particular farm
Reducing energy use: Energy-related greenhouse gas emissions from the agricultural sector can be reduced in a number of ways, including the use of more fuel-efficient machinery
Restoration: Forest restoration in general can result in net emissions reduction as forests sequester more carbon than it loses.
Replacing fossil fuels by renewable energy sources: Fossil fuels used in machinery/vehicles may be responsible for large CO2e emissions. Thus, transitioning to renewable fuels is an alternative to reduce these emissions.
Restoration of degraded lands and cultivated organic soils: Agricultural soil is a dynamic biological system that both stores and releases greenhouse gases. Whether or not the soil acts as a net source of CO2e or a net sink for CO2 can be influenced by soil management. By increasing soil organic matter levels growers can decrease CO2e emissions and increases the soil carbon sink.
Rice management: Cultivated wetland rice soils emit significant quantities of methane. Emissions during the growing season can be reduced by many practices. For example, draining the wetland rice once or several times during the growing season effectively reduces methane emissions
Seed variety selection: Varietal selection of seeds to minimize GHGs.
Selective logging: Techniques used to harvest trees of commercial interest, ensuring the integrity of structure and functionality of natural forests are beneficial for climate change mitigation. Selective logging may represent emissions reductions compared with other harvesting techniques.
Selecting species to maximize carbon capture: Carbon sequestration rates vary according to plant species. For forest plantations or in restoration projects, fast-growth species may be selected to accelerate carbon capture.
Species introduction: Introducing grass species with higher productivity or carbon allocation to deeper roots has been shown to increase soil carbon. For example, introducing legumes into grazing lands can promote soil carbon storage.
Timing of farm operations: A diversity of crop types and varieties are grown in rotation can help spread the risk of losing an entire year's production. Some producers also stagger their seeding and therefore harvesting dates by choosing a variety of crops that require a range of growing conditions so that crops are at different stages (and therefore more or less vulnerable) if and when climate/weather conditions start having a negative impact. A longer and warmer growing season may allow earlier planting and harvesting dates, so that the extremely arid conditions of late summer are avoided.
Waste management: The disposal and treatment of waste can produce emissions of several greenhouse gases (GHGs), which contribute to global climate change. Sustainable waste management encourages the generation of less waste, the re-use of consumables, and the recycling and recovery of waste that is produced.
Water Management: Irrigation measures can enhance carbon storage in soils through enhanced yields and residue returns. The drainage of agricultural lands in humid regions can also promote productivity (and hence soil carbon) and suppress nitrous oxide emissions by improving aeration.
A broad range of agricultural water management practices and technologies are available to spread and buffer production risks. Enhancing residual soil moisture through land conservation techniques assists significantly at the margin of dry periods while buffer strips, mulching and zero tillage help to mitigate soil erosion risk in areas where rainfall intensities increase. The inter-annual storage of excess rainfall and the use of resource efficient irrigation remain the only guaranteed means of maintaining cropping intensities.
The use of artificial systems to improve water use/availability and protect against soil erosion, is also considered to be an adaptation mechanism.