ABSTRACT
Without wet, water, now or in the past, there is no wetland. The details of that water, its level, movement, fluctuations and chemical quality determine not just the major type but also the details of the development of a wetland, its exact habitat type, and to what sort of dry land it can be brought by human impact. The general principles and patterns are shown in Basic Figures 1-14, Basic Charts, and Figure 6.1. Regrettably, in view of impact, it is advisable to study both the pre-drainage and the drained landscapes together. Moving from left to right, on the Basic Figures, there is the rain-fed, raincreated blanket bogs, and the former bog of the moor. A small lake (lochan or tarn), run-off fed, has a reedswamp. At the bottom of the hill, gathered run-off creates a flush, wet and, because the water is moving, bathing the soil, giving a higher nutrient status than if this same water was still. The diagram combines several habitats that could not co-exist in such a short and flat plain. The flood plain itself, once regularly flooded, is now not so. The part near the river is still frequently flooded, and receives water from the river in three ways.
