As we know, scientists evidence gathered in the last couple of decade suggests that climate conditions are changing rapidly and that this treend wil likely continue and even accelerate. These anticipated changes in climate baseline, variability and extremes will have far-reaching consequences on agriculture and crop suitability. As the concentraton of greenhouse gas in the atmosphere is rising,which long term consequence on climate and crop suitability e. Map show the rise in temperature on earth.
The approach used in this project is the same used in those following paper already published for Cassava and Sorghum
Or the suitability analyses already published for Banana, bean, potato – chapter of the crop adaptation to climate change book.
To analyze the potato vulnerability, the EcoCrop model is used. This model was developed by Hijmans et al. (2001) and it evaluates impacts of climate change on agricultural production. It evaluates on monthly basis if there are adequate climatic conditions within a growing season for temperature and precipitation… The model first requests ten different parameters: Tkill (temperature at which the crop will die in celsius), Tmin (minimum temperature at which the crop will grow in celsius), Topmin (minimum optimum temperature at which the crop grows in celsius), Topmax (maximum optimum temperature at which the crop grows in celsius), Tmax (maximum temperature at which the crop will grow in celsius), Rmin (minimum amount of rain water required for the crop to grow in mm), Ropmin (minimum optimum amount of rain water required for the crop to grow in mm), Ropmax (maximum optimum amount of water for the crop to grow in mm), Rmax (maximum amount of rain water below which the crop grows in mm), Gmin (minimum length of the growing season in days), and Gmax (maximum length of the growing season in days). Using these parameters, the model computes a suitability index for temperature and rainfall separately in order to compute a final suitability rating by multiplying temperature and precipitation suitabilities. Figure 1 shows the mechanism of the model. We have selected 50 of the most widespread crops (according to area harvested) reported by FAOSTAT, and have queried their growing parameters in the Ecocrop database in order to run the model.
Worldclim = Current conditions (interpolations of observed data, representative of 1950-2000) Gbif=global biodiversity information facility. GBIF is an international organisation that is working to make the world's biodiversity data accessible everywhere in the world. GBIF and its many partners work to mobilise the data, and to improve search mechanisms, data and metadata standards, web services, and the other components of an Internet-based information infrastructure for biodiversity. Genesys: gateway to genetic resources= portal information about plant genetic resources for food and agriculture – with germplasm accessions from genebanks around the world.
Here is a primary global change in suitability analysis for 50 crops done in 2009. We can see that mostly crops will be negatively impacted by climate change. Indeed, a negative change of -1 to -30 will be found in Africa, South America and India.
I will show an example of what we do for those 26 crops. It is a vulnerability analysis of each crop.
Based on literature and the calibration step, we define the ecological crop parameters.To use the Ecocrop model we need to define a killing temp, min abs temp,min optimum temp, max opt temp, max abs temp and the same for rainfall.
According to the EcoCrop model, present suitable potato cultivation are identified and greatly overlapped with the actual fraction area covered by potato. Highly suitable areas are located in Central and South Africa, South America but not in the Amazon part (Brazil), Mexico, Europe and the major part of China. Potential area estimated by the model is greater than current potato fraction areas, in part because we have to take other limitations in account which alter potato production such as soil characteristics not included in the model used. Another raison about the largest potential potato area is because this model not included the areas where potatoes are growing under irrigated conditions.
Current climatic constraints were identified by modifying each of the eight marginal and optimum growing parameters of potato (Tmin, Topmin, Topmax, Tmax, Rmin, Ropmin, Ropmax and Rmax) by 5% and recalculating suitability with each modification (8 runs). The parameter producing the maximum difference with the original calculation indicates the most constraining factor. Most high latitude area, such as North Europe and Russia are limited by minimum temperature (cold stress), while subtropical regions such as Brazil, South Africa, China, Nepal and Bangladesh are mostly limited by maximum temperature (heat stress) (Figure 1(c)). Only few areas are limited by drought.
Future climates used to calculate future suitability correspond to statistically downscaled outputs of 24 Global Circulation Models (GCMs) (Ramirez and Jarvis, 2008) from the third and fourth reports of the Intergovernmental Panel on Climate Change (IPCC 2001, 2007), for the 2030s and the emission scenario SRES-A2. Future climate suitability for potato cultivation will be mostly negatively impacted by climate change by 2030 (Figure 1(d) (e)). In the tropical highlands, in southern Africa and in high latitudes, potato suitability will be the most affected (until -39% of suitability change). However, areas in very high latitude such as northern of North America and North Europe will gain in suitability (from 0 to 20%) . This suitability gain can be associated with the current climate constraints of the region which are the minimum temperatures. With warmer temperature predicted by 2030, those areas will be positively impacted by climate change.
The impacts of breeding were estimated by altering Topmax for heat tolerance, Topmin for cold stress, Ropmin for drought tolerance and Ropmax for waterlogging tolerance, in stepwise of 5% for precipitation and 0.5 °C for temperature. It will evaluate the sensitivity of the temp and precipitation variations and simulates piossible breeding scenarios. The Figure 2 shows the likely benefits of breeding for abiotic constraints and having a new parameter combination. Regarding to the Figure 2(b), heat tolerance was found to have the greatest impact on cropped lands and the non-cropped lands. This is confirmed by the main current climatic constraints of potato which is heat. Also, cold tolerance would bring opportunities for expanding the agricultural frontier of potato. Potatoes tolerating drought will bring new suitable area where from now there is no potato cultivation. To know more about the adaptation strategies and the potato responses to climate change effects, see Schafleitner et al. (2011). Potato, Solanum tuberosum , is largely cultivated around the world, whether in developing countries or in Europe. Potato is majoritaly sensitive to heat but also to cold and drought conditions. With the climate changing, the suitable potato areas will change. Indeed, climate change is predicted to have in many cases a negative impact on potato production. Specific breeding strategies for the potato crop need to be studied to increase stress tolerances such as heat, cold and drought tolerance. An advantage is that it exists a large diveristy of potato landraces and potato wild relatives that could be used for abiotic stress tolerance improvement (Schafleitner et al.(2011).
We also looked at the regional impact. For potato, as we saw on the suitability changes map, North Europe will be positively impacted by climate change whereas the majority of the regions would be negatively impacted such as Brazil, South Africa, central europe.
Some comparison can be done across crop. Here we compare the suitbility changes for 6 differnet crops around the world. It seems that banana would have the best overal suitability change in the future. It can guide to know what to cultivate and how.
Looking at regional level, for Africa, only sorghum will be positively impacted by CC, the 5 other crops would be negaltively affected.
In LA and caraibes, It is banana the best crop
If you are interseted in looking at some crop suitability maps already done. In our interface amkn “adaptation and mitigation knowledge network” you can already find some maps. We will provide the other suitability maps when analysis will be done.
Mer F - Crop suitability analysis
16 May 2012Flora Mer, Patricia Moreno, Carlos Navarro, Julián Ramírez
The concentration of GHGs is rising Long-term implications for the climate and for crop suitability
Modelling changes in crop suitability EcoCrop: how does it work?It evaluates on monthly basis if thereare adequate climatic conditionswithin a growing season for …and calculates the climatic suitability of thetemperature and precipitation… resulting interaction between rainfall and temperature…
Input dataModel training•Present-day climates from WorldClim = Interpolations of observed data, representative of 1950-2000•Crop distribution data (GBIF, GENESYS, other sources)•An idea of the crop’s ecology, its distribution, andgrowing season duration•Some literature reviewModel projection•24 different climate models (2030, SRES-A1B), tosample uncertaintiesAdaptation strategy testing•Genetic adaptation by extending ecological ranges
Crop suitability is changing….Preliminary analyses (~2009) Average projected % change in suitability for 50 crops, to 2050
Potato regional impacts AND Andean Region NAM North America BRA Brazil NEU North Europe Cen. America CAC and Caribean SAF South Africa Sahel CAF Central Africa SAH South Asia CAS Central Asia SAS CEU Central Europe SEA Southeast Asia EAS East Asia SEU South Europe EAF East Africa WAF West Africa EEU East Europe WEU West Europe WAS West Asia OCE Oceania NAF North Africa SAM South Latin America