Avoiding poverty traps in Tanzania
While feedbacks can help keep a system in a desirable regime, they can also lock a system into an undesirable configuration.
For instance, in drought-prone areas of Tanzania, population growth has increased the demand for crop production and reduced fallow times. This has led to the depletion of organic matter in the soil and a drop in soil fertility. This, in turn, means that crop harvests are low, and that farmers have little or no surplus to sell, and therefore no money to buy fertilisers to restore or increase soil fertility. The consequence is that they become trapped in a vicious cycle of poverty. In these cases it may be necessary to disrupt or weaken the feedbacks that lock the systems in an undesired configuration. In Tanzania, for instance, rainwater harvesting and conservation tillage can help restore soil fertility and reduce the impacts of drought. This can help increase harvests so that small-holder farmers start accumulating wealth that they can use to buy fertilisers, further improve harvests, and break the poverty trap in which many are stuck.