Environmental Engineering Reference
In-Depth Information
Chapter 1
The physical environment: introductory
ideas and concepts
UPPER WHARFEDALE, NORTH YORKSHIRE: AN
ENVIRONMENTAL SYSTEM
Situated some 45 km north-west of the city of Leeds in northern England lies the village
of Grassington near the river Wharfe. The river Wharfe is one of a series of rivers which
rise in the Pennine uplands of northern England and flow eastwards to the North Sea.
Grassington forms a 'gateway' to Upper Wharfedale, a 17 km steep-sided valley. Upper
Wharfedale has one prominent right-bank tributary, the river Skirfare, occupying
Littondale; other tributaries to the river Wharfe are a series of short, steepgradient
streams or becks entering on the left bank. Wharfedale is one of the dales in the
Yorkshire Dales National Park, and has become attractive to geographers and tourists
alike (Figure 1.1).
The attraction of Upper Wharfedale for visitors, as in all other dales in the National
Park, lies in the unique assemblage of environmental elements which interact to produce
a landscape of great interest and beauty. Figure 1.2 shows how the four factors of (1)
geology, (2) physiographic evolution, (3) climate and hydrology, and (4) ecological and
anthropogenic history work together in this dale. By the word factor is meant a control
which produces an effect . In physical geography it is recognized that these four controls
act together in a complex manner to produce the totality of the physical environment.
Another way of expressing this is to visualize the four controls as inputs into the total
landscape system .
The geology refers to the nature of the solid rocks which underlie any part of Earth's
surface, and the material deposited on the surface from glaciers (till), rivers (alluvium)
and slope processes (colluvium or head). The physiographic evolution includes the
present landforms of a region, their morphology (i.e. shape and size) and the manner in
which they have been formed over time; the study of physiographic evolution is thus both
spatial (i.e. of space) and temporal (i.e. of time). Climate and hydrology include the
pattern of climatic elements (e.g. insolation, temperature, precipitation and wind) and the
movement of water on or in Earth's surface (i.e. the hydrological cycle ). Ecological and
anthropogenic history donate two influences of a biological nature; ecological controls
focus on soils, vegetation ( flora )and animals ( fauna ), whilst anthropogenic history
includes the influences of human beings on all parts of the physical landscape, both now
and in the past.
The geology plays a large part in forming this landscape (Figure 1.3). The rocks are
horizontally bedded Upper Palaeozoic Carboniferous limestones and sandstones which
have been deposited unconformably on Lower Palaeozoic Ordovician and Silurian rocks,
and Wensleydale Granite. The basal Carboniferous unit is about 360 m thick and
 
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