People living with limestone past to present - the evidence and its management
Human associations with limestone areas are global, date from the earliest period of human history to the most recent, represent a range of activities, and are often well preserved. These past human interactions with limestone landscapes have left tangible evidence, a cultural heritage, much of which is of considerable significance. It is commonly accepted today, particularly in Australia and New Zealand, that much of this cultural heritage warrants long term protection, and there is legislation in both countries designed to achieve this. To effect protection of the cultural heritage of our limestone areas, it is necessary that all stakeholders - the land managers, the tourist operators, the visitors, the researchers and the local community - consider the protection needs of cultural heritage in all activities. The best protection, with least opportunity for conflict with other needs, is achieved by being aware of the potential cultural heritage, by survey and assessment of this heritage and its significance prior to developments, using procedures set out in documents such as the Burra Charter and Aotearoa Charter; by forward planning which integrates management requirements; by community consultation; and by adopting options for development and site conservation which will result in minimal disturbance.
INTRODUCTON
There is no doubt that cultural heritage in limestone areas is an issue for management. Not only is there an abundance of cultural heritage in these areas, but much of it is of value to society and future generations as records and examples of our human history. This evidence which can never be recreated once destroyed, can be fragile and easily disturbed by the range of present day activities commonly undertaken in limestone areas, especially cave tourism, farming, forestry and quarrying.
This paper briefly explores the nature of the cultural heritage of karst landscapes, the need to protect this cultural heritage, and then, in an Australian and New Zealand context, explores how this cultural heritage may most effectively be managed. The ideas for management are derived from standard procedures and policy, draw on the requirements of current legislation, and utilise a wide range of experience of cultural heritage management. They also emphasize integrated management and broad based consultation with all stakeholders, including the local community. The bibliography contains a range of documents which are considered to be relevant to managing cultural heritage in limestone landscapes.
While the paper is directed at cave and karst management it examines cultural heritage in the broader limestone landscape. This is because people throughout history, while using caves and shelters, have also operated in the broader landscape, leaving their traces not only within caves and shelters, but outside as well. In some instances, historic use of karst landscapes has been independent of, and hence ignored, the karst features, leaving the main evidence only above the surface. Further, caves themselves do not occur in isolation and their formation, evolution and cultural heritage are related to the broader limestone landscape in which they occur. It is important therefore that the whole limestone landscape is considered in management.
THE HISTORICAL / ARCHAEOLOGICAL EVIDENCE
The association of human activities and limestone is a recurrent theme throughout the history of humanity. For over a million years, hominids to Homo sapiens sapiens have sought out limestone caves and shelters for habitation. Some of the most dramatic and highest forms of art throughout history have associations with limestone - the Palaeolithic cave paintings of Europe and Australia, the huge figures depicted on the chalk downs of southern England, public edifices and temples built from quarried limestone and marbles, and world renowned sculptures of marble such as the Elgin marbles. Karst houses religious and spiritual sites, as for example in the "monastic karst" of Thailand. In Europe and the USA, large caves have been used as sanatoria. There are also associations which reflect day to day human needs and industrial uses, for example the global practice of extraction of flints and cherts from chalks and other Tertiary carbonate rocks for high quality stone tools, quarrying of limestone for lime and for building mortar and the associated historic quarries and limekilns, and more recent historic quarrying for cements and fluxes for other industries. In the last two centuries people have become interested in karst in its own right, visiting and exploring both as tourists and scientists, leaving their own historic and archaeological legacy in karst landscapes. People living in limestone terrain have also had to manage the hazards of karst landscapes, often giving rise to historic and tangible engineering solutions, such as in the case of the Kelly Basin railway in Western Tasmania where structural reinforcement was achieved in a karst area by building stone walls within cave passage below the actual railway line (Kiernan et al. 1989).
Some of the world's most famous archaeological sites occur in limestone areas, and in many cases within karst features in these landscapes. The early hominid sites of Europe and Asia are examples of this, and in some parts of the world this is a primary association with particular areas, for example the Dordogne of France, which proudly advertises this association with a huge figure of Cro-magnon "Man" dominating the landscape at the main entry point. Over 2,000 visitors a day visit the spectacular site of Lascaux II, a recreation of the Palaeolithic art work of the original site. No less famous are the Palaeolithic cave paintings of Spain, or the Chinese caves and shelters which housed the earliest known Asian humans, such as at Chou K'ou Tien. Other famous limestone places are sometimes known more for other associations, but in many cases the karstic nature of the area is critical to their importance. Examples are the religious sites of Muktinath in Nepal, and Lourdes in France.
Amongst the most significant cultural heritage of limestone terrain, are the caves and shelters which contain evidence of early hominids and Homo sapiens hunter and gatherer societies. The values of these sites arise primarily because they are the only locations where evidence of this early part of human history is preserved. In contrast to most "open" conditions, cave environments, particularly dry caves, with their relatively constant conditions, their particular chemical environment, and an absence of erosional agents, provide excellent conditions for preservation of archaeological deposits. The importance of cave sites in preserving this type of information is clearly indicated by looking at the proportion of Palaeolithic sites in limestone in different parts of the world (Whitehouse & Whitehouse 1975). For the middle and lower Palaeolithic of Europe c.80% of sites are in limestone, for the Palaeolithic and Neolithic of Africa c.45% of sites are in limestone, for the Palaeolithic of India c.20%, for the Palaeolithic of Southeast Asia c.40%, and for Australia c.47%. In later human history where time and preservation are not such a critical factor, and where humans were possibly less dependant on natural shelters for habitation or needed to live in the open close to the fields where pastoral and agricultural activities were important for survival, proportionally fewer sites occur in limestone landscapes, but nevertheless there are still a large number which do.
In the recent past, uses of limestone areas have become far more diverse. This is related to a number of factors including the need for shelter, for health and spiritual reasons, the aesthetic attractions of karst landscape and of the caves themselves, the exploitation of limestone for building and agricultural products, and the fertility of limestone areas and the interest in exploiting the conquest resources, through for example logging or farming. This has resulted in limestone landscapes having an extremely rich and diverse cultural heritage, more so than for many other terrain types. This diversity of site types is indicated in Table 1. The full range of site types indicated are to be found in Australia and New Zealand as well as other parts of the world, although since New Zealand has a comparatively recent human history, there is little early use of limestone shelters and caves for habitation and shelter.
In discussing the cultural heritage of limestone areas it is also important to consider not just the individual sites and the value of these, but to look at the human activities that produced these sites and to view the sites as reflecting the patterns of past behaviour. This means that often it is a collection of interrelated sites that may be important, not just a single site. In some cases a large part of a limestone landscape will have cultural heritage value because many elements of the landscape strongly reflect a past way of life. Such areas are termed cultural landscapes, and a common example is in rural landscapes where field shapes and sizes, roads, hedges and other plantings, farm buildings and outbuildings all reflect historical farming practices. In some cases this has profoundly altered the limestone features and resulted in very specific cultural landscapes, for example, on a number of Yugoslav islands where huge volumes of limestone have been moved to create an intensely terraced and dry stone walled farming landscape (Gams 1987). China is also known for its long history of agricultural development of its limestone areas and the resultant cultural landscapes. It also means that what appears to be a relatively unimportant site from its physical remains, may be of importance because of its historical association which may be divorced from that landscape. An example would be the quarries for the Taj Mahal palace in India. The quarries may be small and technologically insignificant in themselves, however because of the significance of the Taj Mahal building, the quarries have considered in such a light for land management.
Table 1
WHY MANAGE THIS EVIDENCE?
The cultural heritage of limestone areas, and particularly karst areas, is frequently an important part of our cultural heritage, and where the cultural heritage has this high value it is generally considered important to protect those cultural heritage sites or places. Reasons for importance vary, but essentially, and as explored above, activities in limestone areas encompass a wide range of human history and provide a relatively large window into the human past, showing us many past activities that took place over a long time span. The generally extremely well preserved deposits in caves and shelters provide a much clearer view through the window into the past than many other archaeological windows. As well as providing good information, heritage value may be related to how important a role a place played in history, or how important its historical associations, or even its current cultural value.
Also of importance in considering the need for protection of cultural heritage is the fact that this heritage is both non-renewable and rarely robust. The continued existence of cultural heritage can be considered at this level to be even more precarious than that of karst features and other features derived from natural processes, which may reform, although not necessarily in the same place and often over an enormous period of time, while cultural heritage, a legacy of people and ways of life that no longer exist, cannot be recreated.
The damage can be through natural processes, accelerated natural processes because of human intervention, or by the direct actions of people. The majority of uses, or management, which ignore the cultural heritage will more often than not result in irreparable damage to, or loss of, cultural heritage. Human visitation is a major problem, as people seem to be drawn to karst landscapes and are particularly attracted to caves, not just in the past but also today. Too many people visiting a cave may change the microenvironment and the only evidence of cultures many thousands of years old may be irretrievably lost within as little as a decade. Activities as seemingly irrelevant and minor as upgrading existing facilities or putting in a walkway to a cave, or a carpark or picnic area in a cave reserve may be a irreversible disaster for unique evidence of historic limestone quarrying, historic cave tourism or prehistoric occupation. Resource utilisation is also a major potential impact on cultural heritage, as they are either intense ground disturbing activities (eg, mining) which are most inimical to site preservation, or are widespread less intensive activities (eg, forest harvesting) which still disturb sites but also cause micro-environment change leading to possible long term disturbance of sites through changed or accelerated natural processes. Ongoing natural processes will also adversely affect sites, and the effect of these in a limestone environment where the ground is subject to major solution and collapse processes, is particularly severe.
An additional incentive for cultural heritage protection is legislation. There is now in most states of Australia, and in New Zealand, legislation which is designed to protect cultural heritage. Australia has Federal and State legislation for both Aboriginal and non-Aboriginal cultural heritage. Tasmania is the only State which lacks legislation for the protection of non-Aboriginal places. New Zealand sites are protected primarily by the New Zealand Historic Places Act.
Clearly then, in our present society a value is placed upon cultural heritage and its fragility is acknowledged, resulting in a social and legislative mandate to protect the important (and representative) elements of the cultural heritage.
MANAGEMENT OF THE CULTURAL HERITAGE
How should the cultural heritage of limestone areas therefore be treated? Much of this cultural heritage will be important today and for future generations and so it is necessary to consider the long and short term cultural heritage protection and management needs. This is best achieved through consideration of cultural heritage in all planning and management of karst and limestone areas, and in all development in these areas.
There are a number of strategies that need to be employed to effectively manage the cultural heritage. These include - identification of any cultural heritage, or potential for cultural heritage to occur, in an area before any possible impacts, normally achieved by survey and documentary and oral research; ensuring that actions which affect the heritage are made using sound decision making processes and appropriate policies and expertise; planning which should include flagging and identifying protection needs at the strategic level of land management planning; and ensuring management is integrated. These strategies and important associated aspects of cultural heritage management are discussed below. While these strategies can be applied to any type of cultural heritage, it is also important that given the range of site types that occur in limestone areas, their condition, contexts and threats, and hence the actual management, of each site or area is considered separately.
Determination of the cultural heritage resource or the potential resource.
Probably the most direct way to protect a site or place, and an obvious first step, is knowing it is there. To achieve this it is useful to have some idea of what the potential cultural heritage of a limestone area is. One can consider the full range of possibilities (for example the range in Table 1), and then narrow this down by knowing something of the history and environment of the area. The knowledge of the resource can be improved by carrying out systematic surveys to locate the cultural heritage on the ground. This latter approach is most efficient if the potential for cultural heritage and its probable location is known, or can be established from other research, including examining archival and oral sources. In the case of historic sites it is usually regarded as most useful to carry out the historic and oral research before field survey is undertaken. It is rare that all sites will be located through this type of approach, particularly in forested areas, because sites may be difficult to observe where the vegetation cover is very thick, and the terrain difficult to negotiate. In this case some understanding of which areas are potentially sensitive for cultural heritage becomes a major management tool.
Determining appropriate management of known sites or sensitive areas - using cultural heritage procedures and standards.
The accepted practice for cultural heritage management is a logical set of steps - identification, recording, interpretation, assessment of significance, determination of conservation policy, determination of management, or a management plan, implementation of the management recommendations, monitoring of the site. There are also particular ways of undertaking these steps to ensure that the outcome, the management of the site or place, is effective and where necessary provides long term protection to the site.
There are guidelines for following these steps, which have been designed by professional cultural heritage practitioners, and which are broadly accepted as the professional standard for cultural heritage management in Australia and New Zealand. In Australia these guidelines are the Burra Charter (Australia ICOMOS 1988), and in New Zealand the recent Aotearoa Charter. Both these charters have been developed from the Venice Charter, international guidelines for the protection of places of cultural significance, developed in the 1960s. The main principles of cultural heritage management embodied in these charters are summarised in Table 2. The Burra Charter, while being broad, addresses mainly the management of historic sites, and at present the Australian government is developing a set of guidelines specifically for management of Aboriginal and Torres Strait Islander places of cultural significance. The principles of the Burra Charter have been further developed into a process for determining management, termed /conservation planning (Kerr 1990). It is important also to recognise that while these charters and related documents are designed for places already considered to have significance and needing protection and/or conservation works, the general principles apply to all sites, and the processes they recommend will also be applicable, but frequently in modified form.
The legislation for the protection of cultural heritage is less relevant at this level, as it provides little direction on how to protect sites. Generally the legislation sets out what is to be protected, and the mechanisms, rather then the procedures for doing so.
Table 2
A critical part of the process is assessing the significance of a place or site. It is the site value that usually determines whether that site needs to be protected or not. Again, there are standard criteria for assessing significance (refer Table 3). These criteria are not always easy to apply because not enough might be known about the site, or about other similar sites which provide a context for assessment, particularly of representativeness. Also the criteria operate at different levels and are often difficult to use in conjunction, or may not be relevant for all sites. There is also a question of how important a site is; does it have enough of a particular value or values to require protection? In some cases even professional experts are reluctant to answer some of these questions, but our knowledge in this area is improving continuously and so consequently are the significance assessments.
Table 3
It is recommended that professional heritage managers be used in the process of determining appropriate management. The whole process of determining appropriate management can be more efficient and achieve the best all round options where heritage professionals are used. Different heritage professionals have different skills and it is important that the right people are used. Experts are particularly useful for the initial stages of recording, contextual research, assessment and development of conservation policy, and it is also recommended that at least one cultural heritage manager be involved through the full decision making process to facilitate the assessment and decision making. If this is not possible then it is important that expert advice be sought in the initial stages of planning or when a site is locates and needs assessment. There are government heritage professionals in both Australia and New Zealand who can be contacted for advice at this level. Local councils or government land management agencies should be able to advise who to contact.
Impact mitigation and conservation - options for site intervention
In most cases cultural heritage places that are of significance, that we have decided are worth keeping, can be managed by what is termed passive management, i.e. by not doing anything to them. They may be undergoing slow deterioration through natural processes, and control of this may be very difficult and time consuming. only extremely rare and valuable sites, for example cave painting sites, may warrant some attempt at halting or slowing this type of deterioration.
Active management, or intervention, is more commonly the case where some environmental change has occurred and a site may be suffering severe impact due to natural processes, commonly wind or water erosion, or where human or animal agents are creating disturbance. In these instances impact mitigation is likely to be more straightforward and effective. In managing a piece of land it is possible that any of the above agents may be operating, sometimes in parallel. However, in the context of karst management it will most commonly be human visitation, or the development or upgrading of infrastructure such as accommodation, carparks, walkways, and picnic areas that will most frequently require impact mitigation. A list indicating types of impacts and possible mitigation measures is provided in Table 4.
In carrying out impact mitigation it is important to keep in mind the principles of cultural heritage conservation, in particular that any intervention should be minimal, reversible where possible, carried out using professional expertise and advice, and fully documented. The process of identification-recording-assessment-management planning discussed above should also have been followed to determine what actions are required, if any. If a site is not important, for example, it may not be necessary to carry out expensive mitigation procedures, it may only be necessary to record the site fully. At the other end of the spectrum of possible actions, a site might be deemed to be so important by the process that the development will have to be altered to avoid the site.
Possibly the most extreme and well known example of site protection in this context is at the Palaeolithic art site of Lascaux in the Dordogne of France. At Lascaux, from their presence alone, the weekly thousands of visitors were altering the micro-environment to such a degree that there was accelerated fungal growth in the cave, and this was covering and destroying the art.
After considering options, the cave was closed and only a small number of people, mainly researchers, allowed to visit. To accommodate the huge tourist interest in the site, a replica of the cave and its paintings, Lascaux II, has been built in a disused limestone quarry and it is this site which the tourists visit. Despite the fact that they are viewing a replica rather than the original, the tourists still arrive in droves, usually more than 2,000 a day.
Managing in the broader context - planning, integration and consultation
Cultural heritage management is not carried out in isolation from the management of other values or from land management more generally. It is crucial therefore that cultural heritage management links with, and is integrated with, other management needs and processes, and the range of land use requirements are fully considered.
This rarely happens automatically, and it is usually necessary to develop processes to ensure that this combined management happens, is efficient and effective, and minimises conflicts and costs. In essence the keys to achieving this are to:
- Create informed managers, public and other stakeholders.
- Ensure all the stakeholders talk to each other.
- Be clear about decisions; follow clear processes for decision making and make sure these are documented.
- Manage strategically; in this sense it is important to look at issues and possible issues well in advance, and in some cases develop strategic planning processes.
Table 4
It is much easier to make decisions when all stakeholders are fully consulted and when these stakeholders have some idea of the issues and processes normally followed. Education is important therefore in ensuring that consultation is more than merely token, since where people can have informed input then that input will be more valuable. The stakeholders are also more likely to be prepared to live with the final decisions where there is a conflict of interests if they feel the proper processes have been followed and that their views have been seriously considered. Also of importance is acknowledging the interests of special interest groups. In the cave and karst management context these groups may be indigenous people with links to sites or the land, recreational cavers, educators or tourist operators. In considering cultural heritage management it is important to bear in mind that while current community views are important, the needs of future generations also need to be considered. This is particularly important where there is conflict between conservation and, for example, a tourist development which may mean short term economic benefit for one person as against the protection of something of value to most of the community for generations to come.
Integration of the different management options is also critical. Looking at part of the picture, or ignoring particular aspects of an issue will not lead to good management decisions. Integration is possibly the most difficult aspect of management but it is well worth attempting it. The first step is to ensure all aspects of an issue are understood, the next step is to make a decision using this broad framework, and trying to meld all the management needs. Addressing the issues at the earliest possible opportunity will help ensure balanced decisions, which are made difficult to achieve once conflicts of interest are perceived and "sides" are taken.
Depending on the level of management, it may also be useful to develop strategic management processes. This is most important for land managers. These strategies will normally be in the form of specialised planning. The Jenolan Cave Management planning process and draft plan (Cameron-McNamara 1988) provides a very good example of the use of a range of these strategies, as well as following an integrative process. Other examples which include consideration of cultural heritage are the Management Decision Classification (MDC) (Forestry Commission 1991) and Archaeological Potential Zoning (McConnell 1994).
The Forestry Tasmania MDC system indicates land uses and priorities for management of State forest in Tasmania where management requirements or special values are known and the management priority has been agreed upon. The classification is a map system, which at the first level shows what areas are designated for wood-production, plantations, conservation, or are undecided, and at a second level which areas within any of the first level land categories have a priority management requirement. These priorities may be for conservation of particular natural or cultural values, reflect different special land uses, such as quarries or transmission lines, or indicate where special treatments are required because of hazards such as landslips or sinkhole collapse. Any actions that occur in State forest need to reflect the MDC requirements, hence it is a useful management tool which guides determination of the actions that can or will occur. It also has the advantage that it allows some assessment of how well any one land value is being managed, and also provides an indication of the balance of total conservation versus development in the land management.
With respect to some values, in particular cultural heritage, it is not always possible, as discussed above, to know or locate more than a very small part of the whole resource of an area. In such cases it is useful for managers to have some indication of the potential of land to contain cultural heritage, and this is normally achieved through some type of prediction provided in mapped form. An example of this approach is the Archaeological Potential Zoning carried out by Forestry Tasmania (McConnell 1995). It uses existing archaeological survey data to predict the likelihood of different environments to contain Aboriginal archaeological sites, and this is translated into mapped form at a scale which is useful for forestry planning (in this case 1:25,000). Prescriptions are attached to the different zones indicating what level of pre-operation survey is required. Prescriptions could also contain directions concerning appropriate levels of protection or intervention. The value of this approach lies in the clarity of the directions it provides, and its compatibility with forestry planning generally. It also assists in strategic planning as it indicates areas that may have to be withdrawn from logging, or logged more carefully, if the predictions of site presence are correct. This type of approach can be relatively easily tailored to meet other management needs, and is similar t the zoning often applied to historic urban precincts (Thorp 1987).
CONCLUSION
Cultural heritage is a part of any limestone landscape. Because of its values and its fragility the management of cultural heritage in context will need consideration, and where the values dictate, protection may be required. The responsibility to consider cultural heritage lies with the land managers, developers and the community in general. The most efficient management is achieved by following standard processes and procedures, utilising expertise, observing legislative requirements, and by integrating cultural heritage management considerations with other management considerations. Management is considerably enhanced by ensuring there is full consultation will all stakeholders throughout the management process, and that management adopts a strategic approach, including well designed forward planning. While this approach may not eliminate all conflicts of interest, and may be time consuming, in the long term it is an efficient and cost effective approach, and managers and developers taking such an approach can feel confident that they will be managing the limestone landscape for cultural values as soundly as possible.
ACKNOWLEDGMENTS
I would like to thank the organisers of the Symposium for including consideration of cultural heritage. I am also grateful to Ingereth Macfarlane, Kevin Kiernan, Angie McGowan & Denise Caughwin for contributing expertise, ideas, facts and comment, and to Ernie Holland for showing that someone listened to at least part of the paper.
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