Workshop report: Farm-household modelling with a focus on food security, climate change adaptation, risk management and mitigation: a way forward

Related working paper at http://hdl.handle.net/10568/21112The workshop entitled: ‘Farm-household modelling with a focus on food security, climate change adaptation, risk management and mitigation: a way forward’ focused on identifying the current strengths and weaknesses of farm and household-level models, and laying out practical pathways to improve these models. This activity followed a recent review on farm household modelling commissioned by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). The workshop took place in Amsterdam, The Netherlands on 23–25 April 2012. The most important conclusions of the workshop were: 1. It is possible to analyse household-level questions related to climate change in a reasonable short (6 months to 1 year) time span with existing tools and the expertise present in the group of participants. 2. Availability of component tools can be an issue; the tools are there but free usability of code and parameters is not always possible. 3. Activities to develop repositories of models and data are urgently needed to increase further development of household models and make better use of existing knowledge. A set of activities will be developed to move the work forward in three CCAFS target regions (West Africa, East Africa and South Asia). The expectation is that the workshop will serve as a springboard for a multi-year initiative that will eventually involve a wide range of participants both within and outside the CGIAR. The challenges associated with climate change, agriculture and food security are considerable, and household modelling has a key role to play in designing and evaluating adaptation, risk management and mitigation options that can help lead to the positive outcomes that CCAFS and research-for-development partners are seeking

Advances in sensing ammonia from agricultural sources

Reducing ammonia emissions is one of the most difficult challenges for environmental regulators around the world. About 90% of ammonia in the atmosphere comes from agricultural sources, so that improving farm practices in order to reduce these emissions is a priority. Airborne ammonia is the key precursor for particulate matter (PM2.5) that impairs human health, and ammonia can contribute to excess nitrogen that causes eutrophication in water and biodiversity loss in plant ecosystems. Reductions in excess nitrogen (N) from ammonia are needed so that farms use N resources more efficiently and avoid unnecessary costs. To support the adoption of ammonia emission mitigation practices, new sensor developments are required to identify sources, individual contributions, to evaluate the effectiveness of controls, to monitor progress towards emission-reduction targets, and to develop incentives for behavioural change. There is specifically a need for sensitive, selective, robust and user-friendly sensors to monitor ammonia from livestock production and fertiliser application. Most currently-available sensors need specialists to set up, calibrate and maintain them, which creates issues with staffing and costs when monitoring large areas or when there is a need for high frequency sampling. This paper reports advances in monitoring airborne ammonia in agricultural areas. Selecting the right method of monitoring for each agricultural activity will provide critical data to identify and implement appropriate ammonia controls. Recent developments in chemo-resistive materials allow electrochemical sensing at room temperature, and new spectroscopic methods are sensitive enough to determine low concentrations in the order of parts per billion. However, these new methods still compromise selectivity and sensitivity due to the presence of ambient dust and other interferences, and are not yet suitable to be applied in agricultural monitoring. This review considers how ammonia measurements are made and applied, including the need for sensors that are suitable for routine monitoring by non-specialists. The review evaluates how monitoring information can be used for policies and regulations to mitigate ammonia emissions. The increasing concerns about ammonia emissions and the particular needs from the agriculture sector are addressed, giving an overview of the state-of-the-art and an outlook on future developments

Genesis reversed: climate change impacts on agriculture and livelihoods in mixed crop-livestock systems of East Africa

Climate-induced livelihood transitons in the agricultural systems of Africa are increasingly likely. There has been only limited study on what such transitons might look like, but it is clear that the implicatons could be profound in relaton to social, environmental, economic and politcal efects at local and natonal levels. The work here was set up to test the hypothesis that sedentary farmers who currently keep livestock in transiton zones that may become warmer and possibly drier in the future may ultmately be forced to increase their reliance on livestock vis-a?-vis cropping in the future. We carried out feldwork in 12 sites in Kenya, Tanzania and Uganda to understand how farming systems have been changing in the recent past. We then evaluated what the impacts of these changes, and further changes in the same directon, may be on household incomes and food security in the coming decades, using crop and household modelling. We found no direct evidence for the hypothesised extensifcaton of agricultural producton in the study sites. Indeed, the processes of farming systems evoluton in East Africa are substantally conditoned by powerful socio-cultural processes, it appears

A review on farm household modelling with a focus on climate change adaptation and mitigation

This study systematically reviewed the literature to evaluate how suitable existing farm and farm household models are to study aspects of food security in relation to climate change adaptation, risk management and mitigation. We systematically scanned approximately 16,000 research articles covering more than a 1000 models. We found 126 models that met the criteria for subsequent detailed analysis. Although many models use climate as an input, few were used to study climate change adaptation or mitigation at farm level. Promising mixtures of methodologies include mathematical programming for farm level decision-making, dynamic simulation for the production components and agent based modelling for the spread of information and technologies between farmers. There is a need for more explicit farm level analyses with a focus on adaptation, vulnerability and risk. In general terms, this systematic review concludes that there are enough techniques for integrated assessments of farm systems in relation to climate change, adaptation and mitigation, but they have not yet been combined in a way that is meaningful to farm level decision makers

Feeding efficiency gains can increase the greenhouse gas mitigation potential of the Tanzanian dairy sector.

We use an attributional life cycle assessment (LCA) and simulation modelling to assess the effect of improved feeding practices and increased yields of feed crops on milk productivity and GHG emissions from the dairy sector of Tanzania’s southern highlands region. We calculated direct non-CO2 emissions from dairy production and the CO2 emissions resulting from the demand for croplands and grasslands using a land footprint indicator. Baseline GHG emissions intensities ranged between 19.8 and 27.8 and 5.8–5.9 kg CO2eq kg−1 fat and protein corrected milk for the Traditional (local cattle) and Modern (improved cattle) sectors. Land use change contributed 45.8–65.8% of the total carbon footprint of dairy. Better feeding increased milk yields by up to 60.1% and reduced emissions intensities by up to 52.4 and 38.0% for the Traditional and Modern sectors, respectively. Avoided land use change was the predominant cause of reductions in GHG emissions under all the scenarios. Reducing yield gaps of concentrate feed crops lowered emissions further by 11.4–34.9% despite increasing N2O and CO2 emissions from soils management and input use. This study demonstrates that feed intensification has potential to increase LUC emissions from dairy production, but that fertilizer-dependent yield gains can offset this increase in emissions through avoided emissions from land use change

Monitoring of Suspended Sediments in a Tropical Forested Landscape With Citizen Science

Catchments are complex systems, which require regular monitoring of hydro-chemical parameters in space and time to provide comprehensive datasets. These are needed to characterize catchment behavior on a local level, make future projections based on models, implement mitigation measures and meet policy targets. However, many developing countries lack a good infrastructure for hydrological monitoring since its establishment is costly and the required resources are often not available. To overcome such challenges in data scarce regions like Kenya, a participatory citizen science approach can be a promising strategy for monitoring water resources. This study evaluates the potential of using a contributory citizen science approach to explore spatiotemporal turbidity and suspended sediment dynamics in the Sondu-Miriu river basin, western Kenya. A group of 19 citizen scientists was trained to monitor turbidity using turbidity tubes and water levels with water level gauges in six nested subcatchments of the Sondu-Miriu river basin. Over the course of the project, a total of 37 citizen scientists participated and contributed to the overall dataset of turbidity. The sampling effort and data contribution varied from year to year and among participants with the majority of the data (72%) originating from 8 (22%) citizen scientists. Comparison between citizen-scientist collected suspended sediment data and measurements from automated stations showed high correlation (R2 > 0.9) which demonstrates that data collected by citizen scientists can be comparable to data collected using expensive monitoring equipment. However, there was reduced precision of the measurements of suspended sediment concentrations at low and high levels attributed largely to the detection limitations of the turbidity tubes and citizen scientists not capturing major sediment export events. Suspended sediment concentrations were significantly higher downstream (109 ± 94 mg L−1), a subcatchment dominated by agriculture and rangeland with low forest vegetation cover, as compared to a subcatchment with high forest cover (50 ± 24.7 mg L−1). This finding indicates that forest cover is a key landscape feature to control suspended sediment concentrations in the region. Future citizen science projects should focus on motivation and engagement strategies and the application of robust methods with improved detection limits and resolution to advance hydrological monitoring

Prolonged low temperature exposure de‐sensitises ABA‐induced stomatal closure in soybean, involving an ethylene‐dependent process

Chilling can decrease stomatal sensitivity to abscisic acid (ABA) in some legumes, although hormonal mechanisms involved are unclear. After evaluating leaf gas exchange of 16 European soybean genotypes at 14°C, 6 genotypes representing the range of response were selected. Further experiments combined low (L, 14°C) and high (H, 24°C) temperature exposure from sowing until the unifoliate leaf was visible and L or H temperature until full leaf expansion, to impose four temperature treatments: LL, LH, HL, and HH. Prolonged chilling (LL) substantially decreased leaf water content but increased leaf ethylene evolution and foliar concentrations of the ethylene precursor 1‐aminocyclopropane‐1‐carboxylic acid, indole‐3‐acetic acid, ABA and jasmonic acid. Across genotypes, photosynthesis linearly increased with stomatal conductance (Gs), with photosynthesis of HH plants threefold higher than LL plants at the same Gs. In all treatments except LL, Gs declined with foliar ABA accumulation. Foliar ABA sprays substantially decreased Gs of HH plants, but did not significantly affect LL plants. Thus low temperature compromised stomatal sensitivity to endogenous and exogenous ABA. Applying the ethylene antagonist 1 methyl‐cyclopropene partially reverted excessive stomatal opening of LL plants. Thus, chilling‐induced ethylene accumulation may mediate stomatal insensitivity to ABA, offering chemical opportunities for improving seedling survival in cold environments

Embedding stakeholders’ priorities into the low-emission development of the East African dairy sector

A growing body of evidence shows that more intensive dairy systems can be good for both nature and people. Little research considers whether such systems correspond with local priorities and preferences. Using a mixed methods approach, this study examined the effects of three intensification scenarios on milk yield and emission intensities in Kenya and Tanzania. Scenarios included (a) an incremental change to feed management; (b) adaptive change by replacing poor quality grass with nutrient-rich fodder crops; and (c) multiple change involving concurrent improvements to breeds, feeds and concentrate supplementation. These scenarios were co-constructed with diverse stakeholder groups to ensure these resonate with local preferences and priorities. Modelling these scenarios showed that milk yield could increase by 2%–15% with incremental changes to over 200% with multiple changes. Greenhouse gas emission intensities are lowest under the multiple change scenario, reducing by an estimated 44%. While raising yields, incremental change conversely raises emission intensities by 9%. Our results suggest that while future interventions that account for local priorities and preferences can enhance productivity and increase the uptake of practices, far-reaching shifts in practices are needed to reduce the climatic footprint of the dairy sector. Since top-down interventions does not align with local priorities and preferences in many situations, future low-emission development initiatives should place more emphasis on geographic and stakeholder heterogeneity when designing targeting and implementation strategies. This suggests that in low-income countries, bottom-up approaches may be more likely to improve dairy productivity and align with mitigation targets than one-size-fits-all approaches