University of Birmingham
Comparatively Assessing the Impacts of Acidification on
Macrobenthic Communities in Upland Lotic Systems
Submitted in accordance with requirements for BSc Single
Honours in Geography
For dissertation format submissions:
I confirm that the number of words is 9963 (maximum 10,000)
This total excludes the title page, abstract, acknowledgements, list of
contents, tables of data, figures and their captions, quotations from primary
data, appendices and references list. It includes ALL other elements.
I declare that this piece of work is all my own, and that any work by others
has been acknowledged.
Signed: Date: 06/03/2025
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, Abstract
Anthropogenic activity, and the variety of lasting impacts it causes on upland freshwater
systems and their stability, have the capacity to alter the chemical and biological
parameters from which overall stream health are measured. Despite ongoing revisions to
policy surrounding the mitigation and remediation of acid-sensitive habitats to their
structures prior to acidification, the biological recovery of riverine communities has proven
a multifaceted to complete, necessitating the recognition of both significant improvements
in chemical conditions and acknowledgement of the temporal span such processes occur
in. Within this study, exemplars of two disparate river systems are called upon, evaluating
the extent to which Old Lodge, an acidified river, has exhibited both chemical and
biological recovery within a span of 30 years. With the circumneutral river Allt a’ Mharcaidh
used as a benchmark for which recovery can be compared, this study considers trends in
macrobenthic communities and water quality parameters to indicate the trajectory Old
Lodge is headed in its recovery. This study draws on quantitative indicators of ecological
health within upland rivers, assessing whether improvements in chemical metrics such as
pH and sulphate deposition indeed result in corresponding effects in biological health.
Whilst Old Lodge is found to be chemically, but not biologically, recovering to any
statistically significant degree, this study emphasises the importance in accounting for the
spectrum of intersecting factors that hinder meaningful macrobenthic community changes,
calling upon conservation efforts to consider the restraints of abiding by single-stressor
frameworks when attempting to foster comprehensive ecosystem recovery.
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, Acknowledgments
I would firstly like to thank my dissertation supervisor Dr M for providing me with
the datasets crucial in this dissertation, as well as for his continued support through the
months of collaboration. I’d also like to thank the UK Upland Waters Monitoring Network
and the wealth of researchers who collected and compiled this data. Lastly, I’d like to thank
my friends, who proofread this work and encouraged me continually throughout it’s
creation.
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, 1. Introduction ........................................................................... 8
1.1 Background ........................................................................... 8
1.2 Introduction of Study Sites ....................................................... 10
1.2.1 Allt a’ Mharcaidh ............................................................... 10
1.2.2 Old Lodge ....................................................................... 10
1.3 Significance and Rationale of Study ........................................... 11
1.3.1 The Importance of Studying Macrobenthic Biodiversity ........... 11
1.3.2 Justification for Research .................................................... 12
1.4 Research Aims and Questions ................................................... 13
1.5 Hypotheses ............................................................................ 14
2. Literature Review ................................................................. 15
2.1 Introduction .......................................................................... 15
2.2 Drivers of Acidification in Upland Lotic Systems ......................... 15
2.3 Macrobenthos as Bioindicators ................................................ 17
2.4 Challenges in Biological Recovery ............................................. 19
2.5 Climate Change as an Individual Challenge to Biological Recovery 21
3. Methodology ....................................................................... 23
3.1 Research Strategy and Frameworks ......................................... 23
3.2 Sample Design ................................................................... 23
3.4 Limitations of the Datasheets ................................................. 24
4. Statistical Framework and Results .........................................
26
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