Design of an Aquatic Biomonitoring Programme, Using the South African River Health Programme as a Case Study

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1 Design of an Aquatic Biomonitoring Programme, Using the South African River Health Programme as a Case Study C. TODD & D. ROUX Department of Water, Environment and Forestry Technology, CSIR PO Box 395 Pretoria 0001, South Africa ctodd@csir.co.za KEYWORDS: Sustainable Water Resource Management, Biomonitoring, Monitoring Programme Design, South African River Health Programme ABSTRACT Sustainable management of water resources requires a balance between water quality and quantity requirements of economic and social development with water resource protection strategies. The National Water Act No. 36 of 1998 allows for effective management of water resources in South Africa. It is stated explicitly within the Act that monitoring of aquatic ecosystems be conducted in order to provide information for management actions. A literature review was conducted to establish a generic framework for the design of a monitoring programme. Design criteria should include the three components of framework-, conceptual-, and implementation design. Within these three criteria, factors such as formulation of objectives, site selection, and statistical analyses of data are addressed. The River Health Programme, a national South African monitoring initiative that was launched in 1996, is used as a case study with which to evaluate the generic framework. Problems experienced since the outset of the initiative are discussed. INTRODUCTION Effective management of water resources in a manner that supports a sustainable economy and society with sufficient quantity and quality of water is essential. In order to do this however, improved water quality monitoring is necessary to facilitate resource protection and to understand ecological change within ecosystems. Biological monitoring, or biomonitoring is a measurement of biodiversity. Biodiversity represents the functioning of an ecosystem as a whole and is thus an indicator of ecosystem health. Biomonitoring measures pre-selected endpoints that reflect ecosystem health, of which the results can be interpreted to answer specific questions. Biomonitoring is thus a type of response monitoring and can be defined as any activity in which inferences about the status and quality of the environment are drawn from structural or functional attributes of individuals, populations, communities or ecosystems (Hart, 1994). In order to establish a monitoring programme, numerous criteria need to be satisfied for the programme to be successful. Examples of such criteria include well-defined programme objectives, as well as selection of indicators to be measured. The various steps to establish a monitoring programme are discussed in detail. In order to provide a framework for a biomonitoring programme, it is important to understand concepts such as ecological integrity and ecological indicators, the basis upon which any biomonitoring programme rests. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 1

2 AQUATIC ECOSYSTEM CONCEPTS RELEVANT TO MONITORING In order to allow for sustainable utilization of the resource, aquatic ecosystems need to be managed within a protection framework. The resource should thus be maintained within a certain ecological state, which will allow for ecological well being as its primary focus (Roux, 1999). A balance needs to be sought between ecological well being, social well being and economic development. In order for resource managers to make appropriate decisions regarding sustainable resource use, they need reliable data and information that will guide them during decision-making. Information regarding the ecological integrity of aquatic ecosystems is the basis upon which effective management decisions can be made. Ecological Integrity Integrity is defined as something that is whole and complete, something that is unimpaired. Kleynhans, 1996, defines ecological integrity of a river as its ability to support and maintain a balanced, integrated composition of physico-chemical and habitat characteristics, as well as biotic components on a temporal and spatial scale that are comparable to the natural characteristics of ecosystems of the region. This definition is based on the concept of biological integrity that has been described as the ability to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity and functional organization comparable to that of the natural habitat of the region (Karr and Dudley, 1981; as cited in Kleynhans, 1996). Habitat integrity in this sense then refers to the maintenance of a balanced, integrated composition of physico-chemical and habitat characteristics on a temporal and spatial scale that are comparable to the characteristics of natural habitats of the region (Kleynhans, 1996). Thus it can be seen that habitat integrity, together with biotic integrity constitutes ecological integrity. In order to measure and assess ecological integrity, indicators need to be identified and selected which will provide the relevant information in accordance with the programme objectives. Ecological Indicators Indicators are considered to be those characteristics of the environment that provide quantitative or qualitative information on the condition of the ecosystem and the extent to which it is stressed by natural or human disturbances. They provide a simple means of estimating the overall condition of ecosystems through consideration of physical, chemical and biological interactions (Uys et al., 1996). Thus, ecological indicators need to measure and assess both biological (for example fish) and non-biological (for example habitat) indicators in order to assess ecological integrity completely. Indicators need to be able to identify perturbations in an integrated manner (Roux, 1999). Resident aquatic biological communities are ideal indicators of overall ecological integrity because they integrate the effects of physical and chemical perturbations. When selecting appropriate indicators for a monitoring programme, due consideration should be paid to the advantages of each indicator group as well as to the objectives of the programme. Indices Ecological indicators are used to give some indication of the environmental conditions of a system how it reacts to change and disturbance. By summarizing ecological condition into a single number, an index of the integrity of that system, can be produced. Alternatively, a series of numbers can give rise to indices of integrity. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 2

3 It is important that information gained from measuring ecological indicators be in a format that is of use to resource managers as well as other stakeholders. DESIGN OF A BIOMONITORING PROGRAMME Effective water quality assessment programmes require the formulation of common objectives between managers who are making decisions and scientists who are obtaining the information on which those decisions are to be made. The data collected must be appropriate for use in the decision-making process. After the objectives have been formulated, a number of testable hypotheses can be proposed and evaluated in terms of what information is required for decisionmaking (Maher and Norris, 1990). The elements of a design process are interactive and so an holistic approach should be taken during the design phase. Framework for Designing a River Biomonitoring Programme Within the broader design framework of a biomonitoring programme, the following components should be addressed: Framework design; Conceptual design; Implementation design. Included in the framework design are elements such as information requirements, a resource management policy, a feasibility assessment as well as clearly defined programme objectives. The conceptual design phase includes aspects such as data management, institutional coordination, site- and indicator selection. Finally, in the implementation design phase, elements such as capacity assessment, operating cost, training, education and reporting formats, are addressed, amongst others. Once these broad framework issues have been proposed, the nuts and bolts of the programme can be determined. The following issues need to be addressed if the programme is to be successful: Goals and Objectives These need to be clearly defined. Both managers and scientists should agree on these. For example, it is important to decide what one is monitoring for. Specific questions need to be formulated that will be answered by monitoring in terms of the reason for monitoring. This problem or reason for monitoring needs to be clearly and unambiguously stated. Some possibilities include: Assuring that water quality is appropriate for particular uses. Assessing compliance with pollution control requirements. Identifying short-term pollution waves and their impacts. Identifying long-term trends in water quality. Reconnaissance survey of water quality for planning purposes. Testing hypotheses relating to structure and function of ecosystems. Investigating some undesirable conditions. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 3

4 The manager needs to be clear about how the information to be collected will be used in the decision-making process. Agreement needs to be reached between manager and scientist on certain issues, for example (Maher et al., 1994): What are the important components of the system and what are the important linkages likely to be? What are the appropriate spatial and temporal boundaries of the study? What precision is required in the data? What accuracy is needed in the data? Do criteria exist to help interpret the data, or is it necessary to answer questions such as the level of significance required at the design stage? Will the data collected be compatible with existing data? What sort of management options exist, and what data might support the analysis of various options in decision-making? Define Study Area It is important to conduct a site visit and assess the area that is to be monitored, so that a solid understanding of the area and associated problem areas can be obtained. Spatial boundaries need to be determined, for example, when monitoring rivers, the spatial boundaries are usually those of the catchment. Site Selection Site selection will depend on the study objectives and what is being studied. Selection of a reference site, which is a site in its natural, unimpacted condition, as well as regular monitoring points, need to be made. The data obtained from the monitoring sites can be compared to the reference site data and inferences then made concerning the ecological state of the monitoring sites. Gather and Integrate Existing Data Diversity-related databases are good sources of existing information that can be used and integrated into the current monitoring programme. Establish baseline conditions From current data, one can determine the extent, distribution and condition of existing ecosystem types and the probable distribution of species of concern. Distribution and intensity of identified stressors can also be mapped. Natural benchmark conditions need to be determined for each biological index to be used. Indicator Selection When selecting appropriate indicators for monitoring purposes, it should be kept in mind that a number of elements should be used, across a range of organizational levels and across a range of spatiotemporal scales. For example, the index of biotic integrity (IBI) has succeeded in combining multiple indicators across a range of organizational levels into a single numerical index. In this index, conditions in the system being observed are compared with those of the reference condition i.e. with those in an unimpaired system, as close as possible to the natural condition. Indicators of physical and chemical state and the indices derived from them are integral to ecosystem health (DWAF, 1995). It is thus important to not only focus on biological indicators, but Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 4

5 those relating to the chemical and physical environment as well. geomorphology, hydrology, water quality etc. Examples include The success of any monitoring programme is based on the selection of appropriate ecological indicators for gauging ecosystem integrity. There is a dilemma in that everything is an indicator of something, but nothing is an indicator of everything (Cairns and McCormick, 1992). The selection of indicators should be based on their value in making a decision on the probability of harm or risk to a particular ecosystem from a particular course of action or exposure. Various criteria can be used to select ecological indices, for example, the indicator must be biologically relevant, i.e. important in maintaining the normal appearance of the indigenous ecological community and unimpaired ecosystem operation; the indicator must be sensitive to anthropogenic stressors; the indicator must be easily measured; integrative and must be able to maintain continuity in measurement over space, time and a wide degree of environmental impact (Cairns and McCormick, 1992). Further requirements of indicators include: the indicator should be sufficiently sensitive to provide an early warning of change and should be distributed over a broad geographical area. Identify Control Areas For each major ecosystem type, identify control areas and areas subjected to different kinds and intensities of stress and management practices. Implement a Sampling Scheme Methods of sampling need to be decided upon, for example, kick sampling as opposed to surber sampling for aquatic invertebrates, as well as factors such as timing and frequency of sampling, replication of samples taken per site, for example. Deciding on sample size is extremely important, as this will have impacts on the statistical analyses of the data and thus the outcome of the study. This is an issue of scale, and the appropriate level of resolution needs to be determined in order to answer the questions posed. Length of Study A time period needs to be decided upon in which sufficient data can be collected to answer the questions posed. Statistical Analysis of Data Acquired Selection of appropriate statistical tools will depend on the information required. Different statistical procedures have different data requirements, so these decisions need to be made before data collection commences. Issues such as precision, accuracy and replication are dealt with here. Once the samples have been collected, they need to be described, for example, number of taxa. Alpha- and Beta diversity can be used to describe the samples. Alpha diversity relates to diversity within a sample, and Beta diversity to diversity between sites. Further statistical analysis may include, assessment of similarity using various methods. The Decision-Making Process A critical link in the entire biomonitoring programme, is that between data collected and derived information, with management actions (Roux et al., 1999). Thus, in addition to protocols dealing Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 5

6 with site selection and indices with which to measure ecological condition, mechanisms must be developed for assessing the monitoring results in the context of management objectives, as well as for deciding on appropriate management activities. Quality Assurance All sampling programmes require a quality assurance programme. The aim of this is to identify, measure and control errors. Major systematic errors to be avoided include faulty sampling device operation, sample changes before measurement and incorrect sample labeling. Cost Effectiveness It is desirable that the cost of sampling programmes be minimized to meet the stated objectives. Rapid biomonitoring protocols allow for rapid, cost-effective sampling methods. Having described a generic framework for a monitoring programme, a case study will now be presented, which will provide for a clear interpretation of the above framework. CASE STUDY: THE SOUTH AFRICAN RIVER HEALTH PROGRAMME A national biomonitoring programme for South African rivers, the River Health Programme (RHP), was implemented and launched in 1996 to monitor and thus improve and conserve the health of South African freshwater ecosystems. A phased approach was adopted for the programme, namely framework-, conceptual- and implementation design. The first phase in the design process began with the framework design. Framework Design The RHP focused on two issues, namely, the qualitative and quantitative information requirements and secondly, the ability of the programme to deliver the information. Within these issues, the following were established: Programme objectives (Roux, 1999): To directly measure, assess and report on the ecological state of aquatic ecosystems in South Africa, through the use of biological indicators supported by ecosystem indicators; to detect and report on spatial and temporal trends in the ecological state of aquatic ecosystems; and to identify and report on emerging problems regarding the ecological state of aquatic ecosystems in South Africa. The programme was identified as being a management information system, producing information for a specific objective, namely that of water resource management (Roux, 1999). Scientists and managers and other relevant stakeholders therefore had to agree on the type of questions to be answered and how these questions would be answered using the current level of scientific development. It was further decided that the primary focus of the RHP would be on the health of aquatic ecosystems. The health is best assessed by studying the fauna and flora that live there. Macroinvertebrates are good short-term indicators of ecosystem health, while fish and riparian vegetation are good long-term indicators of river health. All these are termed biological indicators. In this way, the status of the rivers health can be monitored and if necessary, corrective action taken. Integration of biological- with chemical- and physical indicators will provide information on the ecological status of the rivers. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 6

7 Thus a suite of ecological indicators will enable effective decision-making. Finally, methods to allow for co-ordination and co-participation among relevant stakeholders, as well as for optimisation and pooling of resources needed to be assessed. The second phase concerned that of conceptual design. Conceptual Design The following issues were decided upon during this phase of the programme design (Roux, 1999): The development of a spatial classification system that would allow data from various geographical regions to be compared. A three-tiered hierarchical classification scheme was developed. Level 1 identified ecoregions based on the broad historical distribution patterns of macroinvertebrates, fish and riparian vegetation. Level 2, a sub-regional classification identified river zonation within ecoregions and level 3 or river typing, which account for variation between rivers within a sub-region. A protocol for selecting reference and monitoring sites. Reference sites are the least impaired sites that can be used as a benchmark against which monitoring site data can be compared. Monitoring sites are those sites of which the condition of the river is assessed where it is known to be experiencing an impact on water quality or habitat degradation. Protocols for biological and ecological indicator selection. The RHP focuses mainly on biological indicators, namely fish, invertebrates and riparian vegetation, but does not exclude physical and chemical indicators as these provide the basis against which the state of riverine biota can be assessed. Data management procedures include filing and distribution of data sheets, as well as maintaining and updating local databases as well as sharing a centralised database. Institutional structures and co-ordination includes regional stakeholder involvement, creation of a model of national co-ordination, in which issues such as standardisation of procedures and quality control are addressed, amongst others. Implementation Design Up until the implementation design phase, the nature of the programme design had been theoretical. It was within the implementation design phase that pilot-studies were implemented, to demonstrate on a small scale and report the information to key audiences. Final implementation design should allow for implementation and maintenance of the programme. Issues such as training needs, human resource requirements, start-up costs, amongst others need to be addressed. The RHP is contributing to science-based management of aquatic resource management in South Africa according to national and regional mandate. Within South African law, monitoring plays a pivotal role in reporting on the state of the country s aquatic resources. Policy and Monitoring The ultimate aim of water resource management is to achieve sustainable use of the resource. The South African National Water Act (No. 36 of 1998) provides for a National Water Resource Strategy that will allow for, amongst others, structured implementation of the various components of the Act, included of which is monitoring. Within the context of the Act, a Reserve is identified and described as that quantity and quality of water that is necessary to protect basic human needs, as well as aquatic ecosystems. Thus water quantity, water quality, habitat and biotic integrity all need to be protected. In order to do so, one of the components is that of monitoring. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 7

8 It can be seen that the information generated from the RHP will support national government in assessing and reporting on the state of South Africa s aquatic resources. Problems experienced The RHP began with implementation in the province of Mpumalanga. It has been extremely successful, however, there are provinces experiencing problems to varying degrees. For example, some provinces do not have trained personnel to implement the programme, whilst others have the expertise and capacity to do so. In some cases, there has been ineffective implementation due to factors such as lack of concerned parties perceiving a real need for the RHP or lack of demonstrable results (Murray, 1999). Further problems include the complexity and cost of measuring some of the indices and lack of support from superiors. Numerous actions are being put into place in an attempt to assess the problems and to find solutions. Conclusion Although biomonitoring is not a predictive tool, it is still effective in assessing river health and usually provides instantaneous results. It is cheap and robust, making use of low technology methods. Information gained will assist managers when making decisions relating to changes in water quality and flow regimes and the impact that these have on ecosystem health; formulation of ecologically sound environmental quality objectives and regional and national audits of the status of aquatic environments. References Cairns, J. (Jr.) and P.V. McCormick Developing an ecosystem-based capability for ecological risk assessments. The Environmental Professional. 14: DWAF A National Biomonitoring Programme. Pamphlet issued by DWAF. Department of Water Affairs and Forestry. Hart, D.D Building a stronger partnership between ecological research and biological monitoring. Journal of the North American Benthological Society. 13(1): Kleynhans, C.J A qualitative procedure for the assessment of the habitat integrity status of the Luvuvhu River (Limpopo system, South Africa). Journal of Aquatic Ecosystem Health. 5: Maher, W.A and R.H. Norris Water quality assessment programs in Australia deciding what to measure, and how and where to use bioindicators. Environmental Monitoring and Assessment. 14: Maher, W.A., Cullen, P.W. and R.H. Norris Framework for designing sampling programs. Environmental Monitoring and Assessment. 30: Murray, K National Aquatic Ecosystem Biomonitoring Programme: National Implementation Assessment. NAEBP Report Series No 8. Institute for Water Quality Studies, Department of Water Affairs and Forestry. Pretoria, South Africa. Roux, D.J Design of a national programme for monitoring and assessing the health of aquatic ecosystems, with specific reference to the South African river health programme. Environmental Science Forum. 96: Roux, D.J., Kleynhans, C.J., Thirion, C., Hill, L., Engelbrecht, J.S., Deacon, A.R. and N.P. Kemper Adaptive assessment and management of riverine ecosystems: The Crocodile/Elands River case study. Water SA. 25(4): Uys, M.C., Goetsch, P-A. and O Keeffe, J.H National Biomonitoring Programme for Riverine Ecosystems: Ecological indicators, a review and recommendations. NBP Report Series No 4. Institute for Water Quality Studies, Department of Water Affairs and Forestry, Pretoria, South Africa. Design of an Aquatic Biomonitoring Programme, using the South African River Health Programme as a Case Study 8