The sustainability of most family farms in South Uruguay (88% of the country) is severely threatened by reduced farm revenues, family income, and degradation of land resources. Physical and biological soil fertility, crust formation, lowered water holding capacity and poor soil aeration have been identified as major consequences of soil degradation, being an important yield-limiting factor for most vegetable crops.
Moreover, climate change may induce more extreme weather conditions thereby increasing the risk of erosion, flooding, prolonged droughts and crop failures. Model-based explorations have shown that increasing the use of cover crops and animal manure holds can enhance soil quality and yields (Dogliotti et al., 2005).
However, these practices may be costly for small-scale horticultural farms, which, combined with the inherent variability of biological processes and lack of knowledge, hampers technology adoption. Better understanding of the interactions between crop rotations, inter-crop activities, and their effects on soil physical properties and soil moisture supply capacity (SMS) is thus required to improve the farming systems re-design process.
This project contributes to the exploration and quantification of the potential impact of improved cropping systems on the sustainability of small-scale horticultural farm systems, specifically in relation to the soil organic carbon and SMS (Soil Moisture Supply capacity) dynamics.
The proposed strategy consists of going from a more detailed oriented and mechanistic approach and to distil key dynamics into simple functional relationships and to integrate these into simple decision support systems that can be used to generate strategic and/or tactical production guidelines to farmers.
The methodology includes a sequence of 1) Describing phenomena; 2) Explaining observed behaviour; 3) Exploring management alternatives; 4) Design viable systems.