Introduction
Cacao is one of the most important cash crops in many tropical countries. Cacao is characterized by a wide genetic diversity which is especially high in South America, where its centre of origin is located. For instance, cacao already includes several genotypes and populations. Particularly the diversity in promising traits such as high productivity, high sensorial quality, tolerance to pests and diseases, and tolerance to abiotic stresses (i.e. high temperatures, drought, flooding) represents a key resource to promote the long-term sustainability of cacao cultivation.
Cacao is vulnerable to climate change, which is already affecting cacao cultivation worldwide, causing higher mortality of seedlings and adult trees, declines in yield quality and quantity, and increased incidence of pests and diseases. Introducing material tolerant to climate change in cacao farms represents one of the most promising options to adapt cacao cultivation to climate change.
On the other hand, cacao export from South American countries has recently been impacted by the EU Regulation No. 488/2014 (enforced in 2019), which places a maximum allowable limit to the concentrations of cadmium in cacao that can be exported in the European market. Especially the export of fine or flavour cacao has been impacted as this is typically used in derivates with high cacao content and cannot be blended to reduce cadmium concentrations which do provide a solution for bulk cacao.
This webpage and embedded tool have been developed to provide location-specific information about how to improve sustainability of cacao farms in South America. The tool gives information about the future impact of climate change on cacao cultivation and guides the selection of appropriate propagation material for climate change adaptation. The tool also includes information on the likely cadmium content in soil and cacao beans, and more features are expected to be included.
How does it work
- As the first step, the user is invited to select the coordinates of his/her cacao farm in the map of Peru, Ecuador, Nicaragua, Honduras, El Salvador, or Guatemala. The layers show the suitable area for cultivated cacao under irrigation, rainfed cultivated cacao, wild cacao, and eco-geographical zones under the current climatic conditions, according to the results of the suitability modeling. In the case of the four Central American countries (Nicaragua, Honduras, El Salvador, Guatemala), only the suitable area for cultivated cacao is shown as no wild cacao occurs in these countries, and no eco-geographical zones are shown as a different methodology is used for the selection of the list of gene banks, clonal gardens, and nurseries.
- The tool indicates whether the site is predicted to remain suitable or whether cacao cultivation is likely to be negatively impacted by climate change in the future based on the results of climate change projections (for further methodological details, please refer to Ceccarelli et al. 2021 listed in the Publications tab). In addition, the tool indicates which climatic variables are expected to impact cacao cultivation the most in the selected site and provides some recommendations to mitigate the impact.
- The tool then suggests a list of gene banks, clonal gardens, and nurseries where to select appropriate climate-change tolerant propagation material for the selected site. The list includes contact information and the type of available varieties (for instance promising for high productivity, fine flavour, resistance to drought etc.). For Peru and Ecuador, the list of gene banks, clonal gardens and nurseries is selected using a methodology based on the identification of ecogeographical zones. The tool identifies which areas currently belong to the ecogeographical zones that are predicted to emerge in the selected site in the future. Ecogeographical zones are regions characterized by similar climatic and environmental conditions within the suitable area of cacao. The idea is that to mitigate climate risks, rootstock material should be sourced both from local populations and from populations that currently grow in environmental conditions similar to the ones that are predicted to occur in future. The tool then provides a list of gene banks, clonal gardens and nurseries that are located in these areas where to sources propagation material. It is important to note that the propagation material should be sourced from local cacao varieties, as other national or international varieties do not correspond to the local ecogeographical zone. On the other hand, for the four Central America countries (Nicaragua, Honduras, El Salvador, Guatemala), the tool provides the whole list of gene banks, clonal gardens and nurseries present in the country and, if the information is available. This is because the methodology based on ecogeographical zones cannot be used in Central America since most of cacao materials are international varieties and almost no local cacao varieties are still used in these countries. If the information is available, the list also specifies which subset of gene banks, clonal gardens and nurseries would be best to source propagation material from, based on whether they conserve/sell promising varieties that are tolerant to drought, high temperatures, and/or flooding, and depending on which climatic variables are expected to impact cacao cultivation the most in the selected site (point 2).
- The user can select whether he/she wants to include in the report also the maps showing the phenological stages of cacao. The maps show the corresponding months for the stages start of flowering, start of harvesting, peak of harvesting for each department. The stages are shown for local varieties and CCN 51, and for 2015 and 2020. This information is only available for Peru.
- The user can also select whether(s) he wants to include in the report information about the likely cadmium content in soil and cacao beans in the selected site, as predicted by a model calibrated and projected across the suitable area of cacao cultivation. This information is only available for Peru.
- The results are provided to the user as a report that can be downloaded from the website.