4.2. Impact of Humanitarian Crises on Ecosystems (U. Bloesch, Swiss Disaster Relief-Bern)

Case studies from Rwanda, Tanzania and Zaire were presented. The ecosystems in Rwanda and Tanzania have been affected and modified by human activities over centuries. Ecosystems accustomed to intense human activity (such as in the Rwandan and Tanzanian setting) appear to react better to the consequences of population/livestock concentrations, than ecosystems that have been less affected by human activity (e.g. Zaire). The carrying and recovery capacities of various ecosystems is also affected by the duration of population/livestock concentrations. Recovery of affected ecosystems in general, however, will depend on the intactness of humus and the presence of seeds and seedlings in the ground once the period of stress is over.

Intervening factors which determine the carrying and recovery capacity of an affected ecosystem include the fragility of the ecosystem; local topography; local availability of energy sources; availability of pastures; climatic conditions (heavy rainfall that may wash away topsoil); energy needs of refugees; number and type of livestock; number of refugees; length of stay; and rapidity in which an environmental operation is started.

The aim of an environmental operation initiated following population displacements, therefore, should be to safeguard the physical and socio-economic environment, and focus on the local community to ensure long term sustainability.

The main recommendations that can be drawn from the case-studies include:

· where humanitarian crises can be expected, maps indicating areas with fragile ecosystems should be prepared;

· environmental considerations should be included in the very beginning of a crises. It is recommendable to include an environmental expert in the initial assessment team;

· the local population should be involved in planning the use of land from the very beginning. Efforts should be made to ask people how they want to use the land.