Mixed Farming is common worldwide.
In spite of a tendency in agribusiness, research and teaching towards specialized forms of farming.
Obviously, mixed farming has both advantages and disadvantages.
For example, farmers in mixed systems have to divide their attention
and resources over several activities, thus leading to reduced economies of scale.
Advantages include the possibility of reducing risk, spreading labour and re-utilizing resources.
The importance of these advantages and disadvantages differs according to the socio-cultural preferences of the farmers.
The biophysical conditions as determined by rainfall, radiation, soil type and disease pressure.
Trees in and on the edge of a crop field generally reduce the grain yield, but the combination of the trees (for fodder and timber) and crops is valuable, because each of the components produces useful products for the farm (people and animals included).
Mixed farming exists in many forms depending on external and internal factors.
External factors are weather patterns, market prices, political stability, technological developments, etc.
Internal factors relate to local soil characteristics, composition of the family and farmers’ ingenuity.
FORMS OF MIXED FARMING
Mixed farming systems can be
classified in many ways – based on land size, type of crops and animals,
geographical distribution, market orientation, etc.
Three major categories, in four different modes of farming, are distinguished here. The categories are:
On-farm versus between-farm mixing
Mixing within crops and/or animal systems
Diversified versus integrated systems
The modes of farming refer to different degrees of availability of land, labour and inputs, ranging from
plenty of land to a shortage of land.
On Farm Mixing
PIGS IN SWEDISH CROP ROTATIONS
Swedish farmers and researchers incorporated the natural behavior of pigs in the design of farming systems to improve crop and animal performance.
They dealt with the behavior and performance of outdoor pigs on clover/grassland and with tillage effects resulting from rooting by pigs on winter wheat performance.
Environmental loading in an ecological pig production system (EPS) was 64 percent less than in a conventional production system (CPS) but labour requirements were higher in EPS.
On-farm production of feed in the EPS reduced purchased inputs for feeds by 48 percent compared with CPS.
Levels of tillage caused by rooting pigs and yields of winter wheat grain in the following year were significantly correlated.
Grain yields were greater from the areas treated by pigs compared with mechanical tillage, when soil moisture content was high enough.
Mean daily weight gain varied between 626 g and 811 g for EPS and CPS, respectively.
The increasing live weight indicated a large maintenance
requirement for energy, especially in young pigs, probably due to high levels
of activity in EPS.
Rooting activity increased when soil moisture content increased or supplemental feeding was restricted.
Daily allocation of new land stimulated foraging activity and deposition of urine and faces in the
newly allotted land.
Mixing within crop and/or animal systems
Mixing within crop and/or within animal systems refers to conditions where multiple cropping is practised, often over time, or where different types of animals are kept together, mostly on-farm. Both these systems occur frequently though they are not always apparent.
Within-crop mixing takes place where crop rotations are practised over and within years. For example, a farmer has a grain-legume rotation to provide the grain with nitrogen or a potato-beet-grain rotation to avoid disease in the potatoes.
Plants can also be intercropped to take maximum advantage of light and moisture, to suppress weeds or prevent
leaching of nutrients through the use of catch crops. Examples of mixing between animals are found in chicken-fish pond systems where chicken dung fertilizes the fish pond; in beef-pork systems where pigs eat the undigested grains from the beef cattle dung; or in mixed grazing such as cow-sheep mixes to maximize
biomass utilization or to suppress disease occurrence.
Cows and sheep grazing together in a pasture in the Netherlands to optimize biomass utilization and to reduce disease pressure.
Model farm near Durban (South Africa) where the dung from the chickens is used to fertilize the algae growth in the fish pond
Diversified versus Integrated systems
The distinction between diversified and integrated systems is perhaps the most relevant one for this report.
Diversified systems consist of components such as crops and livestock that co-exist independently from each other.
In particular, HEIA farmers can have pigs, dairy and crops as quite independent units. In this case the mixing of
crops and livestock primarily serves to minimize risk and not to recycl resources.
Integration is done to recycle resources efficiently. It occurs in mixed ecological farms of temperate
countries (here called the mode of new conservation agriculture, NCA), but also in mixed, relatively low input farms of southern and southwestern Australia with grain-legume-sheep mixtures.
Integration occurs most often, however, in LEIA farming systems that exist in many tropical countries where products or by-products of one component serve as a resource for the other – dung goes to the crops and straw to the animals. In this case the integration serves to make maximum use of the resources.
Unfortunately, these systems tend to become more vulnerable to disturbance because mixing of resource flows makes the system internally more complex and interdependent.
In Asia, the integration of livestock, fish and crops has proved to be a sustainable system through centuries of experience.
In China, for example, the integration of fishpond production with ducks, geese, chickens, sheep, cattle or pigs increased fish production by 2 to 3.9 times (Chen, 1996), while there were added ecological and economic benefits of fish utilizing animal wastes.
Environmentally sound integration is ensured where livestock droppings and feed waste can be poured directly into the pond to constitute feed for fish and zooplankton.
Livestock manure can be used to fertilize grass or other plant growth that can also constitute feed for fish.
Vegetables can be irrigated from the fishponds, and their residues and by-products can be used for feeding livestock.
Grazing of livestock under plantation trees such as rubber, oil palm or coconut is a form of crop-livestock integration that is often found in Southeast Asia.
Experiments in Malaysia with cattle and goats under oil palm showed better oil palm bunch harvest and comparable results were found where goats fed under rubber trees.
In rubber and oil palm plantations in Malaysia, the integration of livestock to utilize the vegetative ground cover under the tree canopy increased overall production and saved up to 40 percent of the cost of weed control.
Similarly, sheep helped to control weeds in sugar cane fields in Colombia. This suppressed the costs of herbicides, reduced the cost of weed control by half and provided additional income from meat production. This also occurs where cows graze under coconuts.