Ecological impacts of the Industrial Revolution in a lowland raised
peatbog near Manchester, NW England
Abstract
1. Ombrotrophic peatbogs provide valuable records of environmental
change on long timescales but are rarely preserved in an undamaged state
near the major centres of industrial activity. Holcroft Moss is a rare
example of an intact lowland peatbog in NW England, which provides a
valuable opportunity to trace industrial impacts on vegetation in a
sensitive environmental archive in close proximity to the early
industrialising cities of Manchester and Liverpool. 2. We reconstructed
the environmental changes of a Holcroft Moss before and after the
Industrial Revolution using a high-resolution record of pollen,
non-pollen palynomorphs, microcharcoal, peat composition (organic
content, ash-free bulk density) and heavy metal content constrained by a
radiocarbon and SCP (spheroidal carbonaceous particle) chronology. We
examine the relationship between abiotic and biotic environmental
tracers using principal components analysis and evaluate the role of
local and regional climatic and anthropogenic drivers using canonical
redundancy analysis and partitioning of variation. 3. Results show
significant changes in bog vegetation composition during the last 700
years. From the 14th to 18th centuries AD, atmospheric climate
variability and local agro-pastoral disturbance (grazing and fires) were
the main drivers of vegetation change. From the mid-18th century
onwards, the intensification of regional coal-fired industry contributed
to increases in atmospheric pollutants such as dust, heavy metals and
acid deposition that severely impacted vegetation, driving the decline
of Sphagnum. Grasses subsequently rose to dominance in the 20th century
associated especially with cumulative nitrogen deposition. Although
atmospheric pollution significantly decreased after the Industrial
Revolution, vegetation has not returned to previous pre-industrial
conditions, reflecting the ongoing impact of external press drivers
which pose challenges for conservation and restoration. 4. Synthesis.
Palaeoecological studies are needed to reveal the long-term history of
vegetation degradation and to offer guidelines for restoration and
conservation practices.