Description of typical situation
In large parts of Asia, mixed crop-livestock systems integrate rice production, livestock (poultry, ducks, geese, and pigs), aquaculture, fruits and vegetables, and cash crops. These systems are, for example, found in Bangladesh, China, India, Indonesia, Malaysia, Thailand, Myanmar, and Vietnam. Such farming systems are known as integrated farming systems, referring to the high level of integration among farm activities.
Despite a global trend toward specialization of farming systems, these integrated, smallholder mixed-crop livestock systems continue to be found in regions with high water availability, i.e., river deltas and regions with high precipitation. Farms are small (0.5–3 ha), labor is predominantly provided by household members, land for farm extension is limited, and farm activities are generally market-oriented, though production of rice for household consumption is an important objective. Integration of the different components of the system is achieved through the recycling of nutrients and organic matter: Livestock manure is either applied or deposited directly to (on) the crops or used to fertilize fish ponds, with the sediment of the ponds used as a fertilizer. Crop residues and household wastes may be used for livestock feeding. For example, in the Mekong Delta of Vietnam, these integrated farming systems developed from subsistence-oriented rice monoculture, where the livestock component grew rapidly in response to the market demand for livestock products, fruit and vegetables, and cash crops. The farm activities in such integrated systems are quite labor-intensive and are intensifying in response to increasing market demands and the need to support livelihoods.
Common environmental issues
Integrated farming systems are at risk of accumulating nitrogen and phosphorus through the import of synthetic fertilizers and concentrate feeds as well as inadequate management of nutrients. For example, authors reported the use of soybean meal and wheat flour from Argentina, maize gluten meal from Brazil, palm kernel expeller from the Philippines, and rapeseed meal from India as feed ingredients for poultry and pigs in Vietnam. The use of synthetic fertilizer was also reported to contribute to nitrogen pollution. Such nutrient concentrations cause pollution of soil, water, and air, with repercussions on biodiversity, climate, and human health (Principles 4 and 5).
Globally, across all systems, pigs and poultry contribute about 9% and 8%, respectively, to global (GHG) emissions associated with livestock. This contribution is mainly through emissions associated with feed (60%) and manure storage and processing (27%). It is also reported that the pig production component of integrated systems had a higher GHG emission than specialized pig production systems (context 5). (Principles 3, 4, 5 and 6)
The intensification of the livestock component of integrated farming systems will result in increased feeding of concentrates, which will likely consist of grown maize, soy, wheat, and barley. The resulting pressure on land and water, land use change, and biodiversity losses tendentially caused by feed production are important issues associated with production in this context (Principle 4).