Nutrient recycling for food security and safety in Mekong countries: a closing loop of manure management in smallholder farming
Mekong Institute, Thailand
Integrated manure management is not only important to mitigate greenhouse gases but also a cost-efficient opportunity for smallholder farmers on nutrient recycling in the agricultural system. Manure chain always begins with the collection and ends with the application—the process along the chain of which depends on the knowledge and capacity of practitioners. Sound manure management is required to understand all activities from excretion (dung and urine), collection, housing, and storage; as well as practical knowledge and technology to reap its benefits (i.e. anaerobic digester, treatment, transportation, and fertilizers). Currently, the related policies and regulation on manure management are driven by energy recovery as well as its result to environmental and human health problems, instead of boosting value circularity.
Manure contains nutrients and organic matter and is a prerequisite for maintaining and improving soil health and fertility. The Mekong countries of Cambodia, Laos, Myanmar, and Vietnam are predominated by agriculture activity, and livestock production is rapidly growing in this area. Agriculture production grows beyond domestic consumption to serve the world. However, majority of farmers still adopt the small scale farming system. Normal practices for farmers include direct application of manure on the cultivated land and composting manure with crop residues. Avoiding direct application of manure in the field has reduced cross-contamination of diseases from manure to humans, and assure safe food for consumers.
Nutrient recycling from manure can turn wastes into valuable resources. These are suitable for the integrated farming system in countries within the Mekong region. Apart from richer protein source from livestock production by this system, its waste can be turned into fertilizer with relatively reduced production cost. Nevertheless, proper treatments and value circularity at the policy level can contribute to sound manure management and food safety in the region