Agricultural production in most parts of the world will face less predictable weather conditions than mankind experienced during the intensification of agriculture over the last century. Especially South Asia and Southern Africa could suffer negative impact on several crops when no investments will be made into improved adaptiveness of the production systems. Besides specific technical measures (irrigation, breeding for drought improved or heat tolerant crops), the resilience of whole production systems is a very important focus.
Organic agriculture is a highly knowledge-based technique for manipulating complex agro-ecosystems, for breeding locally adjusted seeds and livestock, and for producing on-farm fertilizers and inexpensive nature-derived pesticides. Such knowledge is a crucial ‘reservoir of adaptations’.
Soil fertility-building and soil conserving techniques bring organic farming in a good position to maintain productivity in the event of drought, irregular rainfall events with floods, and rising temperatures. Such techniques are i) the on-farm flux of manure from livestock production to cropland, ii) the use of composts, iii) the use of leguminous crops and green manure in rotations, iv) diversified crop sequences with permanent soil cover and different rooting depths as well as v) minimum or shallow tillage.
Although organic agriculture is not designed to use water as efficient as possible, different agricultural techniques used in organic agriculture effect water use efficiency of organic arable crops in a positive way. In addition, organic management practices also decrease pollution in water effluent as the main pollutants like mineral nitrogen and pesticides are banned.
An additional strength of organic farming systems is their diversity – including the diversity of crops, fields, rotations, landscapes and farm activities. The high level of diversity of organic farms provides many ecological services that significantly enhance farm resilience. Positive effects of enhanced biodiversity on pest and disease as well as on better utilization of soil nutrients and water prevention are well documented.
Genetic diversity of crops is generally considered a fundamental resource for adaptation and therefore crucial for the stability of food supply. As resilience and robustness to environmental stress are multigenetic characteristics, the in situ conservation and on-farm breeding are likely to be more successful than genetic engineering. There are many initiatives by plant and animal breeders in the context of organic farms.
To conclude, organic agriculture is a productive agro-ecosystem which might be very resilient and adaptive to climate change scenarios