Foro Global sobre Seguridad Alimentaria y Nutrición (Foro FSN)

Sr. Peter Bolo

International Center for Tropical Agriculture, CIAT
Kenya

1) Biodiversity is an important contributor to food security and improved nutrition.

Agricultural (cop) productivity and quality of the agricultural (crop) products greatly define food security and nutrition. Biodiversity (belowground and aboveground diversity) greatly influence the crop productivity and quality of products in a myriad of ways.

 Nutrients (macro-and micro-nutrients) like nitrogen and phosphorus are necessary for increased crop productivity. Some of the nutrients are available in limited concentrations in the soil (thus, limiting crop productivity and nutrient balance). However, below-ground biodiversity (macrofauna, mesofauna, and microfauna) often assume active roles in nutrient transformations, involving mineralization, solubilization of recalcitrant nutrients and cycling, thereby increasing their concentrations for crop uptake (leading to increased food production and nutrient balance). 

Certain bacteria and fungi in the soil are beneficial nitrogen fixers, nitrogen mineralizers, and soil stabilizers. in addition, phosphorus, being one of the most limiting nutrients, is often mineralized, solubilized and mobilized by fungi (specifically arbuscular mycorrhizal fungi (AMF)), contributing to increased nutrient availability for plant use. Besides, AMF also helps alleviate drought stress, pests and disease control, BNF, and detoxification of soil pollutants among others, therefore enabling for increased food productivity and nutritive balance in crops. In our study, we noted that the activities of phosphorus mineralizing organisms (enzyme phosphomonoesterases) increased where there was an inadequacy of available phosphorus; and where the soil was more acidic. This implies increased mineralization/solubilization of phosphorus to meet the crop demands (and contribute to improved food nutrition) in such systems, an aspect facilitated by the biodiversity. 

However, it is important to note that a number of agricultural practices (poor agricultural management practices) can greatly threaten the biodiversity structure and composition; abundance and functions. For instance, removal of residues from the farm after harvesting, sole application of inorganic fertilizers without any soil amendments, and practicing conventional tillage, greatly impaired microbial proliferation and activities.  However, practicing conservation agriculture was associated with increased microbial abundance, diversity, functions, and enzyme activities, increased soil aggregate stability and improved crop yields...aspects that were directly positively correlated with the microbial abundance. 

These collectively point towards the connection existent between biodiversity, food security and improved nutrition.