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A systematic process for selecting representative research natural areas
Abstract
Prioritizing sites as potential research natural areas (RNAs) to represent a set of target vegetation types can be a complex planning problem in which competing objectives, such as suitability and efficiency, must be satisfied simultaneously. The current U.S. Forest Service manual contains guidelines on the desired qualities of RNAs but provides little in the way of a structured methodology for selection. We propose an explicit and repeatable generic process for selecting target vegetation types and potential RNAs to represent them. The process is based on a systematic description of vegetation and environmental variation in an ecoregion, analysis of patterns of vegetation and land ownership and management, and optimization of site selection based on both vegetation and environmental criteria. Detailed ground survey and administrative review as currently practiced are integrated into the process. An application to site RNAs representing four forest types on Los Padres National Forest on the central coast of California demonstrates key aspects of the process. This reserve selection process could also be readily adapted to similar regional conservation planning programs.
... In the United States, national programs of research sites include the Long-Term Ecological Research network funded by the National Science Foundation (Franklin et al. 1990), the Man and the Biosphere program (Batisse 1982), research natural area programs of several federal agencies (USDA Forest Service 1994), and the National Estuarine Research Reserve program of the US Fish and Wildlife Service, biodiversity observation sites (Mervis 1998), coral reef reference sites (Jameson et al. 1998), global change monitoring sites (Bailey 1991) and teaching and research reserves operated by academic institutions. The University of California Natural Reserve System (UC-NRS) (Norris 1968, Cheatham et al. 1977 While these programs have developed qualitative criteria for evaluating the suitability of sites as research reserves, they generally lack a formal, explicit procedure for comparing candidate sites (Stoms et al. 1998). In practice site selection inevitably involves a trade-off between conflicting goals. ...
... This process delineated 623 assessment units, ranging in size from 136 to 12,285 hectares, with a mean size of 2,027 hectares (slightly less than half the size of Stage 1 assessment units). These assessment units are still larger than many UC NRS sites, but they are compatible with the resolution of the regional data on biological, environmental, and administrative factors (Stoms et al. 1998). ...
... da.gov/mlra/sstatus.html). Our assessment of the proposition that a parcel is an excellent example of a vernal pool complex was based on the interpretation of the soil map, which may be substantially revised in the next generation of mapping. Some inventory has occurred for specific locations, but none is available for the entire assessment region.Stoms et al. 1998). Without a more explicit set of criteria and quantitative measures of suitability, planners are vulnerable to bias in their assessments. There is no standard against which to judge a candidate site. Superior sites may be overlooked when only a single candidate site is considered. While there is a need for flexibility in an assessment p ...
... Given the uniqueness of each conservation scenario , it is unlikely that any single criterion could be considered best, and a variety of criteria have been applied (e.g., Soulé & Simberloff 1986; Vane-Wright et al. 1991; Witting & Loeschcke 1995; Howard et al. 2000; Rothley 2002). A second challenge is that typically no single criterion can satisfy the multiple, potentially conflicting objectives (Vane-Wright et al. 1991; Stoms et al. 1998; Rothley 1999; Sarkar 1999) imposed on reserve networks (e.g., the largest patches may not contain the most rare species). Similarly, it is unlikely that any single reserve network could be optimal with respect to all selection criteria and still satisfy all constraints (e.g., funds for procuring land). ...
... One solution is to rank the urgency of patch protection according to vulnerability or irreplaceability (Pressey & Taffs 2001). A complementary approach considers the frequency with which patches appear in the optimal alternatives (Stoms et al. 1998). For example, because three patches appear in over 30 out of 34 of the optimal reserve-network alternatives for the SO, the consideration of these patches is a priority. ...
SUMMARY When creating protected area networks in fragmented landscapes with limited ecological data at hand, one approach is to use design criteria, such as patch size or edge/area ratios, to rank the ecosystem patches' conservation value (e.g., habitat integrity, biodiversity) and evaluate protected area network alternatives. Caution is warranted, however, as the relationships between these design criteria and the ecosystem patches' true conservation value may be inconsistent. Conflicts are also likely to arise, as no single protected area network will be optimal with respect to the multiple objectives that protected areas are frequently expected to satisfy. Computer-based decision support tools, such as multi-objective integer programming (MOIP), can be used to search for optimal solutions and simplify the reserve network identification process. Here we describe the consideration of alternate design criteria and the application of MOIP on a real reserve network selection scenario for the rare sandplain natural communities on Martha's Vineyard Island, Massachusetts.
... Based on 3,505 presence records Marxan selected a total of 62 1 × 1 km UTM grid cells, drawing up a network of sites compliant with the objective that every threatened species occurs in at least one site in the final solution. Of the 62 grids 12 were selected as irreplaceable sites in the optimal solution ( Stoms et al., 1998). These grids, numbers 1-12 in Fig. 1 and Supplementary Table S3, correspond to sites on Alborán Island, south of Sierra de Gádor, in Cabo de Gata-Níjar Natural Park, along the coastline and in the highlands of eastern Almería, in the Guadiana Menor valley and on the high plateau of Topares. ...
Networks of protected areas are one of the
main strategies used to address the biodiversity crisis.
These should encompass as many species and ecosystems
as possible, particularly in territories with high biological
diversity, such as the Spanish arid zones. We produce a
priority ranking of the arid zones of south-east Spain
according to the rarity and richness of their characteristic
flora and the level of endangerment. The resulting hierarchy
shows that optimal zones for the preservation of the flora are
located outside the network of protected areas. In particular,
it is important to extend the network and encourage the
creation of microreserves in the depression of the River
Guadiana Menor (Granada), where there is least protection.
This river valley is a particularly important arid site because
of its unique flora and fauna, and palaeontological and
archaeological findings.
... GIS can be used for spatial modeling of population distribution and frequencies (Davies et al. 1990;Ferrier and Smith 1990;Pressey et al. 2000). These extrapolations from census data can ultimately be used for gap analysis, reserve evaluation, and optimized selection of additional reserves for species that are underprotected (Davis 1995;Pressey et al. 1996;Stoms et al. 1998;Lipow et al. 2004). ...
We present a comprehensive approach to carry out community-wide assessments of in situ conservation of forest trees based on basic botanical and ecological data. This is a first step, resulting in a consistent framework to set priorities for collection and inclusion of species- specific biological and genetic information. We use botanical sample data to generate high-resolution distribution maps as a basis for a gap analysis of how well each species is represented in protected areas. To account for adaptive genetic variation of tree species we stratify populations by ecological zones that represent different macroclimates. In a detailed example for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), we show that under certain conditions this approach can pinpoint gaps at the level of genetically differentiated populations without actually using genetic data. In a comprehensive case study, evaluating the outcome of a major protected area expansion between 1991 and 2001 for British Columbia, we demonstrate how extensive results from a community-wide GIS analysis can be summarized and presented for decision-making. We provide methods to identify and efficiently cope with in situ conservation gaps, where lack of data or low protected area coverage requires additional conservation efforts or collection of better data.
Guidelines for assessing sites as potential reserves for scientific study tend to be very general. Translating these imprecise qualities into measurable ranking criteria in a large landscape can be particularly challenging. Here, we evaluate the usefulness of the Ecosystem Management Decision Support (EMDS) system to assess suitability of sites to serve as a potential new reserve to support the research and teaching mission of the University of California Merced campus. The assessment was performed iteratively at three geographic scales, narrowing the spatial scope but increasing the detail of the criteria at each subsequent stage. The products of the assessment were the identification of a small number of high suitability parcels to be field inspected, and a flexible, transparent framework for assessing new areas in the future. Although the criteria might vary among reserve systems, our basic approach and use of EMDS could be readily adapted to other reserve systems in the U.S. and abroad.
The purpose of this project is to identify the most resilient sites in the Northwest that will collectively and individually best sustain terrestrial biodiversity even as the changing climate alters current distribution patterns. The central idea is that by mapping key geophysical features and evaluating them for landscape characteristics that buffer against climate change (topoclimate and permeability), we can identify the most resilient places in the terrestrial landscape in order to guide future conservation investments.
This report and all the associated data and projects are available at: http://nature.ly/resilienceNW
LEGAL Fabiano Guimarães Costa (ESALQ/USP, Brasil) José Vicente Caixeta-Filho (ESALQ/USP, Brasil) Eugênio Arima (Imazon, Brasil) RESUMO O governo brasileiro tem proposto grandes projetos de infra-estrutura de transportes em algumas das principais vias das regiões Centro-Oeste e Norte. Estes projetos têm a intenção explícita de melhorar o escoamento da produção do Centro-Oeste e estimular a expansão da área plantada de soja no país, deslocando esta fronteira cada vez mais para o norte. No entanto, estas áreas apresentam estrutura básica precária, contando com deficiências nos setores energéticos e de transportes, o que prejudica a produção agrícola comercial. Mesmo a viabilidade técnica da produção é questionada, devido à alta pluviosidade, deficiência dos solos e inexistência de variedades adaptadas à região. Observa-se também um potencial conflito entre a intenção de produzir e desenvolver a região Norte, e a de preservar a maior floresta tropical do mundo, além do potencial conflito por terras indígenas, comunitárias e unidades de conservação decorrente do desenvolvimento da região. Nesse sentido, com o apoio de Sistemas de Informações Geográficas, foram analisados dados geo-referenciados da Amazônia Legal. Os resultados em forma de mapas, ilustram o alcance econômico da soja, que sobrepostos com outros mapas (como áreas com grande riqueza de biodiversidade ou identificação de pólos consumidores dos produtos de soja), contribuem para a elaboração de políticas públicas e estratégias comerciais para o desenvolvimento sustentável da Amazônia.
We investigated a complex planning problem often faced by managers of nature centers or non-profit organizations focused on conservation and public education: how to select sites on which to locate new habitat reserves. Mission statements of these organizations often indicate objectives of both habitat preservation and public education. Inherent in land preservation is limited access to reduce the impacts of human traffic through the area. In contrast, for visitors to fully experience an ecosystem, some access to the site is required, hence seemingly parallel objectives may actually be in conflict. In order to address this problem, we formulated the Educational Nature Reserve Model, combining optimization modeling and geographic information systems (GIS) for generating, visualizing, and evaluating alternative solutions. This model fits situations where conflicting goals of conservation and education must be considered when determining the best location for a new habitat. As a case study, the Kalamazoo Nature Center's main property in Kalamazoo County, Michigan, USA, was examined for the best location on which to reconstruct a native tallgrass prairie. The Educational Nature Reserve Model proved beneficial in the site selection process at the Kalamazoo Nature Center, quickly generating many alternative solutions and allowing trade-offs of objectives among decision makers.
Maintaining representation of a full range of ecosystem types is a widely accepted strategy to conserve biodiversity in protected areas. We evaluated representation in the central coast region of British Columbia, a forested landbase containing a complex mix of management options, administrative and ownership types, and disparate ecological and economic objectives. We found that most ecosystem types were well represented outside areas subject to management activities, but a minority were poorly represented. When we examined areas under consideration for protection or special management, we found that they failed to represent many of the most poorly represented ecosystem types and incorporated limited amounts of the remainder. Because these poorly represented types were relatively limited in area, it should be possible to adjust proposed reserve areas to improve representation of these types with limited impact on other values. Failing to do so will result in increased opportunity costs to improve representation in the future. Despite the limitations of ecological classification systems to represent biodiversity, they are an improvement over strictly ad hoc approaches because they employ a systematic, repeatable approach in selecting reserve areas.
Multivariate analysis provides an effective context for the examination of some significant aspects of biodiversity and conservation. The framework is a multidimensional space that integrates sample sites, taxa and environments. This approach enables terms such as representativeness, complementarity and irreplaceability to be integrated within an intuitive and practical framework for reserve design. Cluster analysis is proposed to determine what is there by defining a set of complementary clusters. These clusters are sampled in a representative manner; from the core outward. The degree of irreplaceability of a site is defined as the multivariate distance of each potential reserve site to its nearest neighbour.
Problems arising from application of the representative criterion for conservation and natural heritage evaluation are discussed. An ecological basis to this criterion is suggested that focuses on those key environmental factors dominating biotic response. A methodology is proposed that utilizes computer-based methods of establishing and interrogating spatial data bases (geographic information systems), environmental modeling, and numeric analysis. An example is presented illustrating some of the advantages and limitations of classification and dimension reduction techniques in both defining bioenvironments and displaying their spatial distribution. The advantages of this method for representativeness evaluation are that it maximizes the utility of available data, is explicit and repeatable, and enables large areas to be analyzed at relatively fine scales.
Many public facility location models have been developed using maximum service distance criteria. Most of these models can be classified as covering modes. This paper expands on the notion of service coverage where the value of coverage is not a constant as in previous models. This varying coverage value when coupled with the Maximal Covering Location Problem yields a set of new models which are more complex but still tractable. These new models provide an approach that is sensitive to many of the issues found in public facility location. Both convex and nonconvex covarage functions are discussed along with their potential use in locating noxious activities.
It is argued that the problem of choosing a subset of candidate reserves as the components of a reserve system can, in the right circumtances, be sensibly and routinely formulated as a mathematical programming problem, namely an integer goal programming problem. This remains true even when the entities being reserved are known to exist on candidate reserves only in a probabilistics sense. An example using data describing 101 remnant patches of bush on the Eyre Peninsula, South Australia is presented.
Past work ascribing priorities for the selection of nature reserves has weighted attributes and applied formulae in a single stage process. This single application of a formula means that areas of differing priority may contain similar mixes of species, communities or habitats, and may thus lead to imbalance in representation when preservation takes place, with some previously unpreserved or poorly preserved species, communities or habitats being found in several of the new reserves, and others being absent. An iterative method that has been applied to assess priorities for the preservation of threatened species in the central east coast of Tasmania overcomes this difficulty. The area with the highest score in the initial stages of analysis is assumed to be preserved and the weightings of attributes are altered accordingly. These new weightings are applied to locate the area of next highest priority, and the process continues until predetermined preservation goals are met.
A prerequisite for preserving maximum biological diversity in a given biological domain is to identify a reserve network which includes every possible species. Two algorithms are presented which define the smallest number of wetlands on the Macleay Valley floodplain, Australia, which include all of the wetland plant species. One of these algorithms maximises species richness. The other is constrained to ensure each of nine wetland types is represented, as well as all species.To represent every plant species at least once, only 4·6% of the total number of wetlands is required, but they constitute 44·9% of the total wetland area. In order to represent all types of wetlands, as well as all plant species, 75·3% of the total wetland area is required. The results can be constrained to achieve other conservation goals such as preserving naturalness, rarity, population size, etc., by imposing conditions on rules within the algorithms. In this way a reserve network chosen to maximise diversity can be manipulated to optimise other conservation values.
Many alternative approaches have been proposed for setting conservation priorities from a database of species (or communities) by site. We present a model based on the premise that reserve selection or site prioritization can be structured as a classic covering problem commonly used in many location problems. Specifically, we utilize a form of the maximal covering location model to identify sets of sites which represent the maximum possible representation of specific species. An example application is given for vertebrate data of Southwestern California, which is then compared to an iterative solution process used in previous studies. It is shown that the maximal covering model can quickly meet or exceed iterative models in terms of the coverage objective and automatically satisfies a complementarity objective. Refinements to the basic model are also proposed to address additional objectives such as irreplaceability and flexibility.
Conflicts between human development of the landscape and conservation of biodiversiry will continue to grow. Given this reality, there have been a number of attempts to model the optimal selection of conservation reserve sites such that maximum biodiversity protection can be attained within a limited budget for land acquisition. Here we adapt the Location-Allocation module of ARC/INFO to solve the problem of representing, or covering, as many species as possible in a fixed number of selected reserve sites. Resident ARC/INFO solution routines are applied to an innovative ‘logical’ network that converts the problem of optimal reserve selection into a problem of optimal facility placement, which the Location-Allocation module can recognize and solve. Use of this unique logical network structure as input to ARC/INFO's internal solvers makes possible, compared to previous methods, a much tighter integration of spatial optimization tools with mapping and database tools, all of which are internal to the GIS and accessed via a menu-driven interface. The main advantage is that users of public domain data (such as the US Gap Analysis data) can conduct their own explorations of possible reserve systems without having to acquire and master optimization packages and reformat model output data for GIS display and post-analysis of solutions. Our sample application uses species data from south-western California. We also present a second major form of species-covering model grounded in the same logical network. This enhanced modcl accommodates weighting of species by their conservation importance, thus allowing reserve systems to be designed around the protection of the most threatened or vulnerable biota.
The intention and practice of conservation reserve selection are different. A major reason for systems of reserves is to sustain biological diversity. This involves protecting examples of as many natural features, e.g. species, communities or environments, as possible. In reality, however, new reserves have rarely been dedicated for their representation of features. Furthermore, the opportunism that has characterized the development of reserve systems can actually jeopardize the representation of all features in reserves through the inefficient allocation of limited resources. More systematic approaches are essential if reserves are to play their role in protecting biodiversity. Some basic principles for conservation planning are emerging from recent systematic procedures for reserve selection. These principles will help to link intention and practice.