environment of the Niger Delta through the people who live in it, the discussions are based on real communities with whom ERA has worked. These communities include:
- The Botam-Tai district of Ogoni in the Lowland Equatorial Monsoon Ecozone;
- The Anyama district, just south of Yenagoa in the Freshwater Alluvial Equatorial Ecozone;
- Sangana and Akassa Sand Barrier Island;
- The Okoroba-Nembe district in the Brackishwater Alluvial Equatorial Ecozone (mangroves); and
- A number of urban communities in Port Harcourt.
Our knowledge has developed in a circular way. By working with communities we get to know the ecosystems of which they are part, and we build up our understanding of the whole ecosystem. This leads us back to reassess earlier work and points us in new directions. For instance our early work in Ogoni in 1993 led us to the slum communities of Port Harcourt to consider them partly as the result of rural land degradation, and then to consider the urban areas as major components of the whole Niger Delta ecosystem. By the time we got to the Anyama district we were looking at the environment with the hindsight of a lot more knowledge than with which we had worked in Botem-Tai in Ogoni: in turn we learnt more at Anyama, for instance about the nature of rural human population densities, which made us reassess our views about Botem-Tai. Each community with whom we work raises new issues about people's relationship to ecosystems, so that we are continually reassessing our data.
The following chapters show how we describe ecosystems as a series of layers: topography; soils; the natural ecosystem (the inter-relationship of topography, soils and vegetation in a given climate); and people as part of the ecosystem. To understand the ecosystem at any place (be it in your own compound or on the farm or in the forest) one has to look at a section through these layers: it is like cutting through a layer cake.
We want to give you the reader a picture, in your mind's eye, of what it is like to be part of a human ecosystem that is not your own. And finally we want to stress that ecosystems are dynamic and when we describe an ecosystem and the human relationship to it we are, by necessity, describing it as it WAS at a point in time: not as it IS for ever.
