First of all, not all the agriculture takes place in rural areas. For example, Afton Halloran of the University of Copenhagen says that in the city of Dar es Salaam in Tanzania, approximately 40% of the population is formally or informally involved in urban agricultural practices. In the context of the ongoing urbanization in developing countries, rapidly growing cities raise a lot of problems that need solving. Johannes Schlesinger along with his other colleagues from University of Freiburg and Rhodes University have researched the impacts of urbanisation on livelihoods in African mid-sized towns, with a special focus on the impact of natural resources. They researched which part of income was produced through agricultural practices and whether the households profited of time and spatial changes. Starting with the fact that agricultural practices do play their role in terms of earning income, and that they increase in frequency the further you go from the city centre, Schlesinger et al. found that the peri-urban areas are the most dynamic in terms changes: They are where conflicts and transformations take place. Local and larger scale programme policies are thus needed to reduce livelihood vulnerability and to secure food- and land security. The problem is, that when asking the decision-makers in the rapidly growing African cities about the agricultural practices, they answer that there are none. Thus, the very first step for town planning in developing countries would be to realize the importance of agricultural practices in them, Schlesinger emphasizes.