ENVIRONMENTAL ARCHAEOLOGY IN NORTH-EAST AND CENTRAL WALES (CLWYD-POWYS)

 

 

 

Astrid Caseldine

 

(CADW Environmental Archaeologist, University of Wales, Lampeter)

 

 

 

Mike Walker

 

(University of Wales, Lampeter)

 

 

 

 

 

 

 

 

A. Caseldine (1990): Environmental Archaeology in Wales. CADW Welsh Historic Monuments & St David's University College, Lampeter

 

A. Caseldine (2003): Environmental Archaeology in Wales. 2nd edition, CADW Welsh Historic Monuments & University of Wales, Lampeter (in preparation)

 


 

 

 

INTRODUCTION & CONTEXT

 

 

Strength of palaeoenvironmental studies is the ability to provide a record of both CONTINUITY and CHANGE within the landscape

 

 

Important to distinguish between research focusing on PALAEO- ENVIRONMENTAL RECONSTRUCTION and research which is more overtly concerned with ENVIRONMENTAL ARCHAEOLOGY.

 

 

The former may or may not include an archaeological dimension; the latter invariably will. The human element is crucial in the latter.

 

 

Evidence available at a range of spatial scales: SITE > LOCAL > REGIONAL

 

 

At one end of the spectrum is the SITE SURVEY which invariably involves excavation; at the other the LANDSCAPE SURVEY which may or may not include an excavation component, but which may be linked to one

 

 

For example: FUNERARY & RITUAL SITES project: combination of archaeological excavation/survey and palaeoenvironmental analysis


ENVIRONMENTAL ARCHIVES

 

Existing archives:   Lakes, mires and bogs   )        Off-site

                             Buried soils                     )        Off-site and on-site

                             Tufas                              )        Off-site and on-site

                             Ditch fills                        )        On-site

                             Posthole fills                             )        On-site

                             Middens                         )        On-site

                             Cave sediments               )        On-site

                            

Potential archives (opportunities):       

 

Fluvial sequences:

 

 Under-explored in NE and C Wales

         

          (a)     Rivers as indicators of climate change

          (b)     Rivers as sites of human occupation

(c)     Rivers as archives of human impact on the landscape: alluviation and incision

 

Multidisciplinary approach involving archaeologists and geomorphologists: variety of scales: catchment scale -> individual reaches

 

Work in the Ystwyth, but potential in the Elan Valley, in the Severn, and in some of the North Wales Valleys 

 

The coastal archive

 

More limited in NE Wales: but,

 

          (a)     Coastal wetlands and human activity

          (b)     Midden sites

          (c)     Dune-building episodes and phases of sand-blow

 

Again, some work undertaken (e.g. Prestatyn are) but potential yet to be realised

 

Key to both of the above: involvement of archaeologists with earth scientists


THE ENVIRONMENTAL RESOURCE BASE

 

1.       Pollen analysis: Key technique

 

Strengths:    (a)      Found in a range of deposits    

                   (b)     Stratified sequences - vegetation change through time

                   (c)     Matrix can often be dated by 14C

                   (d)     Preservation                                       )       NE & C

                   (e)      Wide range of potential sites              )           Wales

 

Weaknesses: (a)     Taphonomic problems

                   (b)     Inadequate records (Lateglacial?)        )

                   (c)     Few high-resolution sequences            )       NE & C

                   (d)     Few well-dated diagrams                     )          Wales

                   (e)      Few long lowland records                   )

                   (f)      Many sites independent of archaeology )

                  

2.       Plant macrofossils/Charcoal/Wood remains

 

Strengths:    (a)      Natural (local) vegetation                                       

                   (b)     Evidence of human activity: on- and off-site           

                   (c)     Evidence of agriculture: arable/pastoral

                   (d)     Site context evidence               

                   (e)      Preservation

 

Weaknesses: (a)     Too few sites so far investigated          )       NE and C 

                   (b)     Few integrated studies                        )          Wales

 

3.       Animal bones

 

Strengths:    (a)      Evidence of farming

                   (b)     Evidence of diet

 

Weaknesses: (a)     Preservation                                                                                                                                               

4.       Mollusca                                                                        )

5.       Insects                                                                            )

6.       Diatoms                                                                          )

7.       Ostracods                                                                      )  Importance

8.       Testate amoebae (rhizopods)                                         )        of

9.       Marine fossils (foraminifera, etc)                                  )   integrated

10.     Lipids (animal fats, plant oils, waxes, resins, etc)        )      studies

11.     Soils (phosphates, soil micromorphology)          )

12.     Sediments (particle size, magnetic susceptibility, etc))

13.     Stable isotopes                                                                )

14.     Documentary sources (Historic period)                           )

 

 

CHRONOLOGY

 

1.       Radiocarbon

 

Strengths:    (a)      Wide applicability

                   (b)     Recent developments:      calibration (INTCAL; OXCAL)

                                                                   AMS - single entity dating

                   (c)     Dating of on-site and off-site events: basis for correlation

                  

Weaknesses: (a)     Analytical precision

                   (b)     Contamination and related problems

                   (c)     Cost

                   (d)     NE & C Wales: few well-dated sites   )         e.g. Waun Fignen

                                                  few multi-dated sites    )          Felen

                                                  many 'bulk sediment' dates

 

2.       Dendrochronology

 

Strengths:    (a)      Age in calendar years

                   (b)     Basis for inter-site correlation

                   (c)     Dendroclimatology

                   (d)     Coastal peats                            )        ? NE Wales

 

Weaknesses: (a)     Master curves required

                   (b)     Few sites (if any) so far investigated   

 

3.       Pb210 (very recent sediments)

4.       TL/OSL (sands; pottery)

5.       U-series (cave sediments)

6.       Amino-acid racemisation (marine molluscs)

7.       Cosmogenic nuclides

8.       Tephrochronology

 

 

THREATS

 

 

1.       Drainage of wetland sites

2.       Liming of sites

3.       Afforestation of uplands

4.       Road developments                  )        Although potential here for 

5.       Industrial developments )        developer funding         


SOME KEY RESEARCH QUESTIONS/RESEARCH ISSUES IN NE and C WALES  

 

1.       The climatic/vegetational sequence over the longer timescale, especially during the Lateglacial (Late Palaeolithic).

 

2.       Effects of climate change on human activities  (eg. in Late     Bronze Age; in Dark Ages, in Medieval period): agricultural practices;       farm abandonment; cultivation limits.

 

3.       Evidence for Mesolithic human impact - landscape management?

 

4.       When did pastoralism become established in NE and C Wales?

 

5.       Origins of agriculture in NE and C Wales - when did cereal cultivation begin?

 

6.       Spatial and temporal changes in prehistoric woodland clearance    (upland/lowland contrasts: Cambrian Mountain; lowland valleys etc).

 

7.       Human agencies in upland peat formation in C Wales?

 

8.       Upland/lowland contrasts in prehistoric agricultural activity (e.g.    Brecon Beacons and Wye Valley; Plynlimon and Severn Valley).

 

9.       Regional contrasts in farming regime during Bronze Age and Iron Age (cereals; pastoralism?).

 

10.     The development of field systems during the 2nd and 1st millennia BC.

 

11.     Impact of Roman occupation on agricultural activities in C and NE Wales?.

 

12.     Environmental impact of prehistoric mining, etc.

 

13.            Environmental conditions at and surrounding funerary and ritual monuments?

 

14.             Role of plant and animal remains in burial and ritual practice.

 

 

More integrated studies needed:  (a)    EXCAVATION and SURVEY                                                             (b)   MULTI-PROXY approaches

                                                  (c)   ARCHAEOLOGISTS & EARTH                                                                SCIENTISTS