River assessment using benthic macroinvertebrates in the Hindu Kush-Himalaya Region [Elektronische Ressource] : substrate and current preferences and development of an assessment method / vorgelegt von Thomas Korte

Thomas.Korte

Sujets

• Social work
• Biologie

Informations

• Publié par: universitat_duisburg-essen
• Publié le: 01 janvier 2009
• Nombre de lectures: 33
• Langue: English
• Poids de l'ouvrage: 13 Mo

Extrait

River Assessment using Benthic Macroinvertebrates
in the Hindu Kush-Himalaya Region
-
Substrate and Current Preferences
and
Development of an Assessment Method


Inaugural-Dissertation
zur
Erlangung des Doktorgrades
Dr. rer. nat.

des Fachbereichs
Biologie und Geographie
an der

Universität Duisburg-Essen

vorgelegt von
Thomas Korte
geboren in Gelsenkirchen

April 2009
Die in der vorliegenden Arbeit zugrunde liegenden Experimente wurden am Institut
für Biologie in der Abteilung Angewandte Zoologie/Hydrobiologie der Universität
Duisburg-Essen durchgeführt.


1. Gutachter: Prof. Dr. Daniel Hering


2. Gutachter: Prof. Dr. Bernd Sures


3. Gutachter: Prof. Dr. Otto Moog


Vorsitzender des Prüfungsausschuss: Prof. Dr. Hynek Burda


Tag der mündlichen Prüfung: 23.07.2009

“To be clear, an ecosystem is a community of animals and plants inter-
acting with one another and with their physical environment. People are
part of the ecosystem.”
M. T. Barbour
Table of Contents
GLOSSARY AND ABBREVIATIONS ........................................................................ 8
STATE-OF-THE-ART............................................................................................... 11
OBJECTIVES AND SCOPE OF THE THESIS......................................................... 19
1 SUBSTRATE AND CURRENT PREFERENCES OF BENTHIC
MACROINVERTEBRATES AS IMPACT INDICATORS OF
HYDROMORPHOLOGICAL DEGRADATION 20
1.1 Introduction...............................................................................................................20
1.2 Material and Methods...............................................................................................21
1.2.1 Study area, site selection and sampling .................................................................21
1.2.2 Importance of substrate type and current velocity..................................................27
1.2.3 Allocation of substrate and current preferences .....................................................28
1.2.4 Quantification of substrate and current preferences...............................................29
1.2.5 Development of metrics..........................................................................................29
1.2.6 Ability of metrics to detect hydromorphological impact...........................................30
1.3 Results.......................................................................................................................33
1.3.1 Importance of substrate type and current velocity for community composition ......33
1.3.2 Allocation of substrate and current preferences .....................................................34
1.3.3 Quantifying substrate and current preferences.......................................................37
1.3.4 Development of metrics38
1.3.5 Ability of new metrics to detect impacts of hydromorphological degradation .........40
1.4 Discussion ................................................................................................................42
1.4.1 Importance of substrate and current velocity for aquatic macroinvertebrates ........42
1.4.2 Allocation of substrate and current preferences .....................................................43
1.4.3 Quantifying substrate and current preferences.......................................................44
1.4.4 Development of metrics..........................................................................................45
1.4.5 Ability of metrics to detect impacts of hydromorphological degradation.................46

2 DEVELOPMENT OF A MULTIMETRIC INDEX FOR ECOLOGICAL RIVER
QUALITY ASSESSMENT ........................................................................................ 47
2.1 Introduction...............................................................................................................47
2.2 Material and Methods...............................................................................................48
2.2.1 Study area, site selection and sampling .................................................................48
2.2.2 Gradient analysis....................................................................................................53
2.2.3 Metrics: Calculation and selection ..........................................................................53
2.2.4 Calculation of the multimetric index........................................................................57
2.2.5 Seasonal effects.....................................................................................................57
2.3 Results.......................................................................................................................59
2.3.1 Gradient analysis....................................................................................................59
2.3.2 Metrics: Selection of candidate and core metrics ...................................................61
2.3.3 Calculation of the multimetric Index63
2.3.4 Seasonal effects64
2.4 Discussion ................................................................................................................74
2.4.1 Metrics: Selection of core metrics...........................................................................74
2.4.2 Development of the multimetric index.....................................................................75
2.4.3 Seasonal effects.....................................................................................................76
3 SUMMARY AND CONCLUSION ...................................................................... 77
4 KURZFASSUNG............................................................................................... 82
REFERENCES......................................................................................................... 92
APPENDIX ............................................................................................................. 104
ACKNOWLEDGEMENT......................................................................................... 105
List of Figures
Figure 1: Impacts on river ecosystems in the Hindu Kush-Himalaya region............. 18
Figure 2: Study area: Lowland, mountains ............................................................... 23
Figure 3: Reference site: Mountain river................................................................... 24
Figure 4: Reference site: Lowland river .................................................................... 24
Figure 5: 20 point allocation procedure 30
Figure 6: Procedure for allocation of substrate and current preferences .................. 32
Figure 7: CCA biplot ................................................................................................. 33
Figure 8: T-value biplots substrate ........................................................................... 36
Figure 9: T-value biplots current............................................................................... 36
Figure 10: New metrics vs. different hydromorphological stressors.......................... 41
Figure 11: Study area: Ecoregions 49
Figure 12: “75%-rule”................................................................................................ 57
Figure 13: Procedure for the development of the multimetric index.......................... 58
Figure 14: PCA biplots.............................................................................................. 60
Figure 15: Example core metrics Himalayan Subtropical Pine Forest ...................... 64
Figure 16: Example core metrics Eastern Himalayan Broadleaf Forest ................... 64
Figure 17: Example core metrics Western Himalayan Broadleaf Forest .................. 65
Figure 18: Example core metrics Upper Gangetic Plains ......................................... 65
Figure 19: Example core metrics Lower Gangetic Plains 65
List of Tables
Table 1: Sampling sites characteristics .................................................................... 26
Table 2: Number and origin of sampled substrate types .......................................... 26
Table 3: Current velocities........................................................................................ 27
Table 4: Summary of sampled taxa .......................................................................... 28
Table 5: Transformation of individual numbers to abundance class values.............. 31
Table 6: pCCA-results .............................................................................................. 34
Table 7: Results Monte Carlo permutations test....................................................... 34
Table 8: Summary Spearman rank coefficients........................................................ 37
Table 9: Substrate preferences ................................................................................ 39
Table 10: Current preferences.................................................................................. 40
Table 11: p-level results of Mann-Whitney U-test..................................................... 42
Table 12: Threshold values of metrics.............