Adaptation – increasing resilience, reducing vulnerability
Agriculture
Plant genetics/plant breeding is particularly relevant with respect to developing crop-varieties which are high-productive and at the same time have improved salt, pests, drought, and flood tolerance. While productivity increase is a more generic goal which can mitigate increased food demand nationally as well as internationally and reduce vulnerability of farmers, developing improved tress tolerance is directly related to adaptation to anticipated climate change impacts.
Genetic Modification or GM is a field which has shown enormous potential for adaptation to direct climate change impacts by increasing stress tolerance and hence lower vulnerability, but also to improve production, nutritional value, and nutrient, water, and other input use efficiencies. However, notwithstanding the potential adverse effects of increased dependence on agri-business companies, recent years have witnessed new challenges for some of the most widespread technologies. A case in point being herbicide tolerant varieties e.g. Roundup Ready crops by Monsanto (now Bayer), where newly developed immunities among weeds threaten the advantages of the GM crops. In many countries, there has been considerable public concern over GM, not least in relation to consumer health and cross-over of modified genetic traits to other plants when cultivated in the open. Although the debate seems to be somewhat emotional and no studies so far have been able to confirm consumer health risk from GM crops (Norris 2015; Paarlberg 2008), it is nevertheless a factor that may seriously hinder the uptake of new improved crop varieties, both on political level and among the public.
Rather than focusing on advanced genetic modification, where a part of a plant’s genes is directly modified with desirable traits from other organisms, marker- or genomics-assisted breeding may show great potential. These technologies use gene mapping and other tools to speed up traditional sexually based plant breeding by being able to quickly screen new seeds for the desirable genetic traits (Searchinger et al. 2014). Using genetically assisted, but basically traditional breeding methods, may help overcome some of the public and political sensitive issues that often surround the use of GM crops. The development and use of gene editing techniques such as CRISPR has further complicated the debate e.g. when only the existing genome is edited and no foreign gene sequences inserted. With a fast-growing global population demanding improved living standards coupled with likely severe constraints on natural resources imposed by climate change, it would seem unavoidable and perhaps even irresponsible not to seek responsible exploitation of these new frontiers in science.
AWD (Alternate Wetting and Drying) reduces water use in wet rice cultivation. Recent research by IRRI has shown that wet rice can be cultivated with shorter periods of flooding of the fields. By draining the field certain intervals during the plant growth, water use can be reduced with up to 25% corresponding to 500L water per kilogram rice produced (CCAFS 2014). AWD is mostly a matter of changed cultivation practice as no extra equipment is needed except for short perforated tubes made of plastic or other material which are used to monitor the level of soil water to determine when renewed flooding of the field is required. The tubes are simple and can be made locally. The existing irrigation and drainage infrastructure is used, but may in some cases need improvement. Being able to drain a rice field in the rainy season may not be possible in all systems, and there may be a need for larger scale coordination of rice farmers and upgrading of water management, especially in gravity-fed irrigation systems. Adoption of AWD is generally expected to be more feasible in pump based irrigation systems than in systems relying on surface water and irrigation canals. Well-levelled rice field are an advantage which may also require improvement for an adopter. Competent extension services support is likely to be a precondition, at least in the technology adoption phase. Quite a lot of research and trials have been made on farm level, but there is a need for further research into the potentials of this technology on a systems scale (Adhya et al. 2014). The reduced water use increases farmer resilience against water scarcity. It also has mitigation effects by reducing energy use for irrigation and by reducing methane emissions from fields with up to 50% or even more with very good water management.
Climate-Smart Agriculture (CSA) is an approach combining a system of techniques and practices which together ensures that the agricultural production systems has minimal GHG emissions and also increases the farmers’ resilience. The three basic pillars of CSA are sustainable productivity increase, building resilience, and reducing GHG emissions. Applying a holistic approach to agricultural development, CSA can target improvements in land and soil fertility management, water use and improved irrigation, crop and livestock variety development and choice, cropping pattern and calendar, combination of production systems e.g. forests, cropping, aquaculture, animal husbandry etc. Implementation of CSA is highly context dependent, and will require locally adapted research and efficient extension services. The approach is strongly promoted by FAO, the WBG, the CGIAR research programme on Climate Change, Agriculture, and Food Security, WBCSD and several other organisations. Private agri-business companies are also increasingly promoting CSA among the smallholder suppliers.
System of Rice Intensification (SRI) set of techniques that can significantly increase yields. It is based on four main principles: 1) early, quick and healthy plant establishment; 2) reduced plant density; 3) improved soil conditions through enrichment with organic matter; 4) Reduced and controlled water application (Cornell University 2017). Combined with selection of seeds well adapted to local conditions, SRI can stimulate plant productivity and reduce water use through AWD. SRI is not necessarily an organic farming system, and is often incorporating synthetic fertilisers and other chemical inputs. SRI can increase resilience and may contribute to mitigation by reducing water, fertiliser, and pesticide use and reduce methane emissions through AWD.
Organic fertilizer from agricultural residues/by-products uses a.o. enzymes to accelerate the decomposition and hence mobilisation of nutrients in cellulose. By improving soil fertility and possibly reducing dependence on in-organic fertilizer, a certain contribution to adaptation is possible. By decreasing use of fertilizers which may require fossil-fuel in the production process, there may also be a mitigation effect.
Direct Planting Systems, Zero-Tillage, Conservation Agriculture are names often used in relation to techniques that allows to grow crops with use of little or no land preparation. Residue crops are left on the field thus protecting it from erosion and increasing soil carbon. Seeds are planted directly in the soil without specific soil preparation. The resulting increased susceptibility to weeds will often require increased use of herbicides. In some cases genetically modified crop varieties are used which are able to tolerate a specific herbicides (e.g. RoundUp-ready crops by Monsanto). The contribution to adaptation comes from improved soil erosion control especially on steep slopes, decreased vulnerability to weed infestation, and less dependence on labour or machine intensive weeding practices. There may also be mitigation benefits through reduced fuel consumption and increase in soil carbon stock which thus acts as a carbon sink.
Biochar (name derived from bio-charcoal) refers to a form of carbon produced under pyrolysis (burning under low-oxygen conditions) of agricultural waste- or by-products e.g. rice husks, peanut- and coconut shells etc. The fine-grained and highly porous biochar can, when worked into the soil, act as a soil fertility enhancer by increasing soil nutrient and water retention thus also increasing resilience to drought in degraded land. In terms of mitigation, biochar may help making an agricultural system carbon-negative by allowing long-term storage of carbon in the soil. The production process also can produce oil and gas by-products which potentially can replace use of fossil fuel.
Agricultural by-product, foliage, and plastic mulching can help improve water management in agricultural systems which are typically high intensive and irrigation dependent. By incorporating straw, hay, and foliage into the soil, the soil water retention capacity can be increased. Plastic mulching entails covering the soil with a thin plastic layer with slits for the desired crop to grow through, and hereby reduce evaporation from the soil and growth of weeds. These techniques contribute to adaptation by making a system more resilient to water shortage and weed infestation, and possibly to mitigation by using less energy for irrigation and weed control.
Shifting from rice to upland grains involves the traditional Vietnamese system of VAC Vuon-Au-Chuong (garden-pond-barn) which combines food gardening, fish rearing, and animal husbandry is a highly nutrient and water efficient intensive agricultural small-scale system. The system has been adapted to different agro-climatic zones in Vietnam by applying various intercropping, soil protection, drainage, and nutrient recycling methods. By combining it with field crops especially in flood prone areas, the system can increase resilience to climate change induced water stress and flooding.
Shifting from triple cropping to double cropping and a shrimp/fish/poultry crop is a measure to maintain intensive food production also under conditions of flooding where a third rice crop is unstable. By replacing this third crop with an activity better suited to this unstable condition, farm productivity can be increased and the farmer will be less vulnerable to flooding.
Forest plant genetics to select and create new drought-, flood-, and pest-resistant species for climate change adaptation in forestry With improved crop varieties and other biotechnological techniques, the forest based productions may become resilient to climate change induced stress factors. A higher area productivity may also lead to less need for plantation areas, and hence better protection of natural forests and biodiversity conservation.
Agro-forestry is an agricultural system where tree crops are interplanted with a single or several other annual or perennial crops. The advantage is a higher diversity of crops, improved pest management, and exploitation of agro-ecological growth niches like shadow etc. In terms of adaptation the higher diversity may increase resilience and prevent soil erosion from high intensity rainfall. As it may prevent burning of forest for cultivation, it may also have mitigation effects.
Forest fire control by GPS and remote sensing could encompass several technologies. Autonomous in-situ sensors could relay early warning data on forest fires to the authorities for faster fire response. This system could also help map particularly forest areas vulnerable to fires. Several satellite based forest fire monitoring systems are already operational which help understand the problem and track illegal forest activities. Prevention of forest fires, and particularly in peat areas which represent large carbon stocks, is primarily a mitigation measure, but preserving forest areas through fire prevention has positive contributions to rainfall generation, soil erosion limitation and forest cover in general which are also positive for adaptation by increasing resilience.
Super Absorption Polymer (SAP) also called hydrogels is a technology of using special polymers which has a very high water absorption capacity. AMS-1 is a Vietnamese variant of this. The material is added to the soil in powder form and when water comes in contact with the polymer chains it is drawn into the molecule by osmosis. When the soil dries up, the polymer releases the stored water and can hence increase the effective water storage capacity of the soil several hundred times. If the SAP is based on starch e.g. from potato, cassava, yams, or corn, the material would be bio-degradable and the environmental impact hence low (Nnadi and Brave 2011). Although the technology has been used for years, it should probably be considered whether there are unwanted long-term consequences of adding large quantities of polymers to natural soils as well as its local cost effectiveness. The technology has the potential to significantly improve water management and possibly reduce need for irrigation which is a valuable contribution to adaptation.
References:
Adhya, Tapan K., Bruce Linquist, Tim Searchinger, Reiner Wassmann, and Xiaoyuan yan. 2014. “Wetting and drying: Reducing greenhouse gas emissions and saving water from rice production.” Creating a Sustainable Food Future no.8. WRI. Washington.
CCAFS. 2014. “New irrigation technique can ease drought effects for rice farmers”. Retrieved June 2017.
Cornell University. 2017. “System of Rice Intensification – SRI Methodologies” Cornell University. College of Agriculture and Life Sciences. Retrieved July 2017.
Nnadi, Fidelia and Chris Brave. 2011. “Environmentally friendly superabsorbent polymers for water conservation in agricultural lands.” Journal of Soil Science and Environmental Management 2:206-2011.
Norris, Megan. 2015. “Will GMOs Hurt My Body? The Public’s Concerns and How Scientists Have Addressed Them – Science in the News” Harvard University” The Graduate School of Arts and Sciences. Retrieved June 2017.
Paarlberg, Robert L. 2008. Starved for science : how biotechnology is being kept out of Africa. Cambridge, Mass.: Harvard University Press.
Searchinger, Tim, Craig Hanson, and Jean-Marc Lacape. 2014. “Crop Breeding: Renewing the Global Commitment.” Working Paper, Installment 7 of Creating a Sustainable Food Future. World Resources Institute. Washington DC. Retrieved July 2017.
Top image shows Super Absorbent Polymers or Hydrogels
Lower mage source: www.socochem.com
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