جنبه های فضایی زمانی از تجزیه و تحلیل هزینه فایده برای مدیریت پارک ها: یک مثال از Khao Yai پارک ملی، تایلند

Using a model calibrated to Khao Yai National Park in Thailand, this paper highlights the importance of generating explicitly spatial and temporal data for developing management plans for tropical protected forests. Spatial and temporal cost-benefit analysis should account for the interactions between different land uses – such as the benefits of contiguous areas of preserved land and edge effects – and the realities of villagers living near forests who rely on extracted resources. By taking a temporal perspective, this paper provides a rare empirical assessment of the importance of quasi-option values when determining optimal management plans.

Resource managers in tropical poor countries create and manage forest parks within a complex setting of ecological characteristics, local people's needs, competing land uses, and divergence between who bears costs and who captures benefits. Spatial challenges arise because positive and negative externalities across adjacent areas of land in different uses may influence both the benefits themselves – such as creating minimum habitat size – and the incidence of costs and benefits – such as whether park neighbors bear significant opportunity costs (Albers, 1996; Ferraro, 2002). Social and institutional challenges arise because of the complex policy and property rights setting in such countries and because park benefits accrue to a wide range of people, from neighboring villagers collecting vegetables to the distant populations that enjoy tropical parks’ contributions to global climate control (Albers and Ferraro, 2006). Resource managers also face intertemporal challenges because the future benefits from these parks are often highly uncertain, and some changes in forest use are irreversible or reversible at a cost (Albers et al., 1996). Yet, although developing countries increasingly dedicate land to parks, few managers take these complex interactions into account in their park siting and management plans due, in part, to restrictive mandates, inflexible plans, and data/information limitations (Repetto, 1988; West and Brechin, 1991; Ghimire, 1994; Albers and Grinspoon, 1997). This paper combines the modeling structure of Albers (1996) – which presents a model for tropical forest management and explores the interactions of spatial and temporal characteristics through stylized parameter values – with information and data from Khao Yai National Park (KYNP), Thailand to explore issues about park management decisions, incentives facing local people, and the need for spatial-temporal data. As is true for all tropical parks, sufficiently detailed spatial-temporal data do not exist to undertake a complete case study. But that problem is part of this paper's point; we make a case for the importance of generating spatial and temporal data for tropical forest management by grounding the analysis and discussion in an empirically-relevant range of values and parameters. The results from the calibrated simulation model demonstrate how forest managers and other stakeholders would manage the forested area differently depending on which spatial, temporal, and equity considerations they take into account. This paper demonstrates the usefulness of cost-benefit analyses to park management decisions, in addition to providing justification of a park as whole, when interactions between areas of different land use, the distributional impact of land use management zones, and temporal changes in values are accounted for. The paper also explores how cost-benefit analyses that identify the incidence of costs and benefits, rather than simply estimating a forest's total value, better equip park managers to address spatial issues and improve conflict resolution. The following section provides background information about the spatial, temporal, institutional, and social aspects of tropical forest park management. The next section describes and solves a spatial-temporal optimization model for park management using KYNP as an example. Much of this section discusses dividing the park into zones, the land use options, the value of those land uses per zone, and the values generated by spatial patterns of land uses. The penultimate section solves the optimization model with different sets of parameter values to discuss differences in management decisions across regulatory settings and across various stakeholder groups. The final section discusses the implications of the findings for the role of cost-benefit analysis in establishing and zoning parks, determining the permitted activities within parks, and highlighting areas of potential conflict. In addition, the final section comments on the importance of rural people's welfare in forest management, the role of the international community in tropical conservation, and the impact of quasi-option values on management decisions.

The application of a multi-zone, intertemporal economic decision model to KYNP, Thailand demonstrates the empirical importance of taking into account intertemporal, spatial, social, and ecological factors in tropical forest park siting and management. The spatial relationships in particular – habitat size, recreational benefits as a function of size, and a positive externality of proximity to preserved land on resorts – appear especially important in determining optimal land management patterns.5 Yet, sufficiently detailed spatial data are not, in practice, available for any tropical forest. Although most cost-benefit analysis can support the establishment of parks, the collection of more detailed spatial and temporal data would inform three critical areas of protected area establishment and management: the types of uses permitted in the protected area and thus the IUCN designation the area receives; the zoning of protected areas to reflect the varying realities and benefits across the area; and the identification of areas of potential conflict through the incidence of costs and benefits of the protected area. During park establishment, the information about values that can be derived from different types of access – such as trekking, day-trips, and NTFP extraction – could be used to determine what access restrictions, and therefore what IUCN classification, the park should achieve. For example, if tourism values are estimated to generate a significant fraction of the forest's potential value, an IUCN classification of “nature reserve”, which allows no tourism, might not be appropriate or justified. Similarly, if NTFP extraction helps to justify the existence of a protected area, the IUCN classification of “national park”, which allows no NTFP extraction, might be overly restrictive, particularly given that the costs associated with preventing such extraction are typically underestimated in cost-benefit analysis. For example, KYNP was designated a national park without zones and without permission for sustainable extraction by local villagers. Yet, as shown above, without the value from extraction included as a preservation benefit in cost-benefit analysis, preservation of the area is more difficult to justify. Despite a growing literature that supports zoning protected areas, viewing parks as a part of a broader landscape, and recognizing heterogeneity across various subunits of a forest, most protected areas, including KYNP, are still established without zones or subunits. Cost-benefit analysis that reflects the benefits and costs from subunits of the area, and the interactions among different subunits, could inform decisions about the size and location of various zones. Yet thus far, the cost-benefit literature provides little guidance to the establishment of zones, such as buffer zones, typically saying little more than that the “size of the zone will depend on the requirements of nearby residents” (p. 198, para. 4; Dixon and Sherman, 1990). Because the entire area of KYNP received the IUCN classification of National Park, official management cannot move toward zones and less restrictive access rules without a difficult process of expanding the area or de-accessioning parts of the park. Despite this constraint, unofficial policies to overlook NTFP extraction for home use and to work with rural development organizations reduce some of the burdens of KYNP on local people and indeed such policies move the de facto management of the park closer to the social optimum, as determined by the stylized full-spatial manager here. A small but growing literature identifies who bears the costs and who captures the benefits of protected areas. Lélé et al. (2001) considers how the establishment of a wildlife sanctuary in southern India has affected different stakeholder groups, including forest dwelling communities, farming communities, local tourists, and the global community. They suggest that a conservation strategy that combines strict protection from external pressures with sustainable use by local communities can be effective and relatively socially equitable. Van Beukering et al. (2003) identifies the benefits and costs faced by stakeholder groups of several land use scenarios, finding that conservation strategies improve equity while “deforestation” benefits the logging industry and increases income disparity. Ferraro (2002) estimates the opportunity costs of Ranomafana National Park in Madagascar borne by local residents to be $3.37 million. Such cost-benefit studies can contribute to a park manager's ability to recognize potential sources of funding – such as international conservation groups – and potential sources of conflict – such as onerous burdens on the rural poor. Lélé et al.'s (2001) analysis explicitly identifies and distinguishes a number of different local users in terms of the extraction benefits that they get from a wildlife sanctuary and the damage they inflict. Similarly in KYNP, local users’ demands on the park are relatively low, such as extraction of fuelwood for subsistence, whereas non-local people's activities are more damaging, such as the recent increases in incense wood extraction and wildlife poaching that have triggered an increased emphasis on law enforcement in KYNP (Mather, 2006). A disaggregated cost-benefit analysis that distinguishes between activities and between the groups that perform those activities could be used to support differential enforcement for more and less damaging activities. Also in the KYNP example presented here, we show that the international community could simply free-ride on Thailand's provision of this preserved area. However, the international community recently granted KYNP, as part of the Dong Phayayen-Khao Yai Forest Complex, the UNESCO Natural World Heritage Status, which brings with it international support and prestige. This example of a disaggregated cost-benefit analysis that recognizes who gains and who loses from KYNP's establishment and management suggests that KYNP might gain further from mechanisms to capture some of the benefits that accrue internationally – perhaps through higher entrance fees for international visitors – and from policies that meet local people's needs in a sustainable manner and discourage open access extraction from the park. Finally, recent calls for more estimates of quasi-option value are thwarted by a lack of appropriate data. In recent years, quasi-option values have been proffered as an argument for the conservation of biodiversity, despite the lack of estimates of those values (Heal, 2004). As a rare estimate of quasi-option values in the tropics and that value's role in land use decisions, this analysis (and the related work in Albers et al., 1996; Albers, 2001) makes four points to that end. First, even large quasi-option values may not alter the land use decision. Second, valuation studies rarely provide the information that is necessary to identify quasi-option values, which requires a description of both the probability of high values from preservation and the magnitude of those potential high values (Albers, 1996; Water Science and Technology Board, 2004). Third, the length of the timeframe considered matters for the size of the quasi-option value and its contribution to current period decisions. Fourth, the availability of land uses that do not irreversibly disrupt ecosystems – such as short term and small-scale agriculture – provides flexibility for managers, enabling them to take advantage of high-valued preservation in later periods.