Cuba

Our project combines since 2017 the recycling of organic waste materials with the production of food, feed, and bio-based energy in the context of Cuba, a country that progresses like only a few others towards a more sustainable and increasingly organic agriculture.

To close the organic nutrient cycles and guarantee sufficient fertilization for higher crop productivity, the methods and technologies to transform a large spectrum of biomass into organic fertilizers have to be optimized. Composting and anaerobic digestion (AD) technologies produce currently most of the organic fertilizing substrates for Cuba, however, nutrient and carbon losses through leaching and greenhouse gas emissions are considerable. To reduce these losses and optimize the processes, the SNF funded Bio-C project intends to introduce pyrolysis as a third, complementary key biomass-transforming technology. Besides green energy, the main product of pyrolysis is biochar, a highly porous material with high adsorption and nutrient exchange capacities, high water holding and redox potentials. These properties make it a versatile material to reduce organic nutrient losses especially in composting, AD, and animal farming. Moreover, the carbonaceous matrix of biochar can be impregnated with liquid nutrients (e.g. animal urine, liquid digestate, fermented sugar cane bagasse) upgrading the biomaterial to a potent organic slow release fertilizer. Advanced organic biochar based fertilizers are expected to be more nutrient effective, crop yield and plant health enhancing and ecologically sensitive than conventional fertilizers.

Mixed cultures agroforestry and silvo-pastures is very the biochar method works the best. And Cubans are best to exploit those opportunities.

Pathways to Impact

The perspective of Bio-C is to develop advanced organic fertilizers that could replace or reduce the deployment of mineral fertilizer. During the first 1.5 years we could see encouraging results both on lab and on field scale. Thanks to the knowledge transfer that occurred in numerous workshops with and for farmers, administrators and scientists, a remarkable enthusiasm about biochar based fertilization arose in Cuban agriculture. While many farmers tried the organic method for the cultivation of their land, several groups of researchers started biochar investigation projects. Moreover, researchers involved in the Bio-C project are invited to conferences and workshops in Latin America to share their new experiences with biochar based soil and plant nutrition.

The main communication channel was face to face by workshops where researchers and experts discussed with farmers, technicians, and directors of Agricultural Productive Cooperatives (CPAs) and the Service and Credit Cooperatives (CCSs). Educative materials were prepared for all of the workshops and handed out to the participants. This includes illustrated guidelines for biochar production, organic fertilization, the application of BCB fertilizers, fermentation and composting techniques. Several educative videos were shared via social media.

From the Swiss side, the project was able to set-up systematic pot trials, material tests and analyses in order to optimize the BCB fertilizer formulations.