TABLE OF CONTENTS     (24 kB)
EXECUTIVE SUMMARY    
ACKNOWLEDGEMENTS     (38 kB)
LIST OF TABLES    
LIST OF FIGURES    
LIST OF APPENDICES    
TERMS OF REFERENCE     (50 kB)

CHAPTER 1. INTRODUCTION TO ECOLOGICAL REFERENCE CONDITIONS AND THE SPATIAL FRAMEWORK FOR DELINEATING HOMOGENEOUS REGIONS

Summary
1.1 INTRODUCTION
1.2 WHAT ARE ECOLOGICAL REFERENCE CONDITIONS?
       1.2.1 Types of reference conditions
       1.2.2 Biotic components for deriving ecological reference conditions
       1.2.3 Why riverine macroinvertebrates?     (20 kB)
1.3 APPROACHES FOR DERIVING ECOLOGICAL REFERENCE CONDITIONS FOR RIVERINE MACROINVERTEBRATES
       1.3.1 Multimetric approaches
       1.3.2 Multivariate approaches
             1.3.2.1 RIVPACS
             1.3.2.2 AusRivAS
             1.3.2.3 Model construction in AusRivAS
             1.3.2.4 The South African approach
1.4 A SPATIAL FRAMEWORK FOR DELINEATING HOMOGENEOUS REGIONS
       1.4.1 Background
       1.4.2 A hierarchical spatial framework
             1.4.2.1 Level 1: Ecoregions or bioregions
            
             1.4.2.2 Level 2: Sub-regions or geomorphological zones
             1.4.2.3 Level 3: River types
1.5 STRUCTURE OF THIS REPORT     (57 kB)

CHAPTER 2. SELECTION OF POTENTIAL REFERENCE SITES AND GROUND-TRUTHING OR PRELIMINARY SITE SCREENING

Summary 2.1 INTRODUCTION
2.2 SELECTION OF POTENTIAL REFERENCE SITES
       2.2.1 Identifying homogeneous regions
       2.2.2 Selection of "least-impacted" sites     (19 kB)
       Table 2.2 Types and characteristics of impacts used...     (23 kB)
       2.2.3 Ground-truthing and site screening
2.3 RESULTS     (29 kB)
2.4. SUMMARY AND CONCLUSIONS     (9 kB)
       Figure 2.2 Distribution of 74 reference sites selected for...     (205 kB)
       Table 2.3 Ecoregion (ER), sub-region (SR), river name, a...    (138 kB)
       Table 2.4 Site Code, active channel width (A), water width...   (186 kB)
       Table 2.5 Key to abbreviations used in Tables 2.3 and 2.4.     (20 kB)
      

3.1 INTRODUCTION
3.2 STANDARDISATION OF DATA COLLECTION
3.3 TECHNICAL CONSIDERATIONS FOR SAMPLING INVERTEBRATES USING SASS
       3.3.1 Separate- or combined-biotope sampling
       3.3.2 Single- versus multiple-season sampling and sampling frequency
       3.3.3 Habitat assessment as a tool for interpreting SASS Scores
       3.3.4 Taxonomic resolution
       3.3.5 Using SASS in non-perennial systems     (47 kB)
       3.3.6 Identification of environmental variables for future predictive
3.4 DATA STORAGE: THE RIVERS DATABASE     (29 kB)

Summary
4.1 INTRODUCTION
4.2 CHARACTERISATION OF REFERENCE SITES
4.3 DATA ANALYSIS     (21 kB)
      Table 4.1 The distribution of 74 reference sites into ecoregion and sub-region showing number of sites in each category or typing.     (33 kB)
      Figures 4.1, 4.2 and 4.3    (113 kB) (104 kB) (112 kB) (msword.doc files)
       4.3.1 Standardisations    
       4.3.2 Statistical methods
            4.3.2.1 Classification and ordination of invertebrate data
             4.3.2.2 Environmental variables
             4.3.2.3 Univariate statistics
       4.3.3 Invertebrate data: classification of reference sites based on composite reference community data
       4.3.4 Environmental variables
       4.3.5 Separate- versus combined-biotope sampling (62 kB)
       4.3.6 Seasonal variation in invertebrate communities and SASS Scores
4.4 RESULTS
       4.4.1 Invertebrate data: composite reference communities
             4.4.1.1 Cluster analysis and multi-dimensional scaling (MDS)
             4.4.1.2 Identification of distinguishing taxa (54 kB)
             Table 4.4 Taxa responsible for similarity within ReferenceGroups(37kB)
             Table 4.5 SIMPER comparison for presence/absence transformed taxa between Reference Groups 1, 2 and 3. (37 kB)
             Table 4.6 SIMPER comparison for presence/absence transformed taxa between sub-groups (28 kB)
             Table 4.7 Frequency of occurrence of each taxon in each composite Reference Group or sub-group. (36 kB)
             4.4.1.4 SASS4 Scores, number of taxa and ASPTs for each Reference Group
       4.4.2 Environmental variables
             4.4.2.1 Descriptive statistics for environmental variables (61 kB)(64 kB)
             4.4.2.2 Future predictive modelling
       4.4.3 Separate- versus combined-biotope sampling
             4.4.3.1 Separate-biotope site classification versus Reference Group classification
             4.4.3.2 The frequency of occurrence of each SASS taxon amongst biotope-groups     (88 kB)
             4.4.3.3 SASS Scores, number of taxa and ASPT
             4.4.3.4 Invertebrate Habitat Assessment System (IHAS)
             4.4.3.5 Summary
       4.4.4 Seasonal variation in invertebrate communities and SASS Scores
             4.4.4.1 Single-season versus multiple-season sampling     (108 kB)
             4.4.4.2 The frequency of occurrence of each SASS taxon amongst seasons     (82 kB)
             4.4.4.3 SASS4 Scores, number of taxa and ASPT
             4.4.4.3 Summary     (63 kB)

5.1 INTRODUCTION
5.2 REFERENCE GROUPS, ENVIRONMENTAL VARIABLES, BIOLOGICAL BANDING AND CONSIDERATIONS FOR DATA INTERPRETATION
       5.2.1 Homogeneous regions and identified river types
             5.2.1.1 A key for assigning a monitoring site to a Reference Group for rivers in Mpumalanga
       5.2.2 Characterisation of Reference Groups in terms of environmental variables
       5.2.3 A biological banding system
       5.2.4 Seasonal considerations
       5.2.5 Biotope considerations
5.3 ECOLOGICAL REFERENCE CONDITIONS FOR RIVERINE MACROINVERTEBRATES FOR PARTICULAR RIVER TYPES IN MPUMALANGA
       5.3.1 Reference Group 1: Central Highlands: Mountain Stream and Foothill-cobble Bed sub-regions
             5.3.1.1 Characterisation in terms of environmental variables
             5.3.1.2 Composite SASS Scores
             5.3.1.3 Expected SASS taxa
             5.3.1.4 Biotope considerations     (66 kB)
       5.3.2 Reference Group 2: Great Escarpment Mountains: Mountain Stream, Foothill-cobble Bed and Rejuvenated Cascade sub-regions
             5.3.2.1 Characterisation in terms of environmental variables
             5.3.2.2 Composite SASS Scores
             5.3.2.3 Expected SASS taxa
             5.3.2.4 Biotope considerations     (32 kB)
       5.3.3 Sub-group 2a: Lowveld: Foothill-cobble Bed and Rejuvenated Cascade sub-regions, with >60% boulder/cobble substratum type
             5.3.3.1 Characterisation in terms of environmental variables
             5.3.3.2 Composite SASS Scores
             5.3.3.3 Expected SASS taxa
             5.3.3.4 Biotope considerations     (31 kB)
       5.3.4 Reference Group 3: Lowveld: Foothill-gravel Bed sub-region
             5.3.4.1 Characterisation in terms of environmental variables
             5.3.4.2 Composite SASS Scores
             5.3.4.3 Expected SASS taxa
             5.3.4.4 Biotope considerations     (31 kB)
       5.3.5 Sub-group 3a: Lowveld: mixture of sub-regions including Foothill-cobble Bed, Foothill-gravel Bed and Rejuvenated Cascade sub-regions, with >60% bedrock substratum type
             5.3.5.1 Characterisation in terms of environmental variables
             5.3.5.2 Composite SASS Scores
             5.3.5.3 Expected SASS taxa
             5.3.5.4 Biotope considerations     (30 kB)

6.1 CONCLUSIONS
6.2 A PROTOCOL FOR DERIVING ECOLOGICAL REFERENCE CONDITIONS FOR RIVERINE MACROINVERTEBRATES
6.3 RECOMMENDATIONS     (38 kB)

APPENDIX A     (48 kB)

APPENDIX B     (22 kB)

for citation purposes:

NAEBP Report Series No 12
Dallas, H.F. 2000.
The derivation of ecological reference conditions for riverine macroinvertebrates
Institute for Water Quality Studies, Department of Water and Sanitation, Pretoria, South Africa.