Keywords

1 Introduction

Chilean Patagonia is considered one of the most pristine areas of the planet due to its low human footprint, which is the product of a reduced and relatively recent history of occupation [14, 36]. In addition, its unique position in the global context, as the continental land mass closest to the South Pole and the Antarctic, confers unique characteristics to its terrestrial and marine biota [9]. This particularity is also expressed in the presence of climatic factors that define its current characteristics, including the proximity to the South Pole ice mass and the presence of the westerly wind belt [10]. This landscape has the particularity of being a territory of recent conformation, where traces of the retreat of the last glacial maximum (ca. 12 thousand years ago) can be seen along its entire length [33].

The large ecosystems present in Chilean Patagonia decrease latitudinally in plant diversity, except for bryophytes and lichens, which dominate in the extreme south of the area [28, 35]. There are three types of forests in the northern sector of Patagonia (41°–47° S): (i) the evergreen forest that extends towards the north of Patagonia; (ii) the conifer-dominated forests, where alerce (Fitzroya cupressoides) and Guaitecas cypress (Pilgerodendron uviferum) are the dominant species, and finally a deciduous forest that marks the transition with the Patagonian steppe. This last ecosystem is exclusive to this area of the world; in Chile it is located in the eastern part of the Andes. In the coastal sector, the evergreen forest is intertwined with moorlands-dominated soils in the lower elevation areas with less slope [42]. A longitudinal pattern can be recognized in the distribution of the main ecosystems, evergreen and coniferous forest with moorlands in the coastal and inland zone, deciduous forest that marks the forest-steppe transition, and the Patagonian steppe, which dominates the entire inland zone and the border with Argentina throughout the area [16]. Fifty-four percent of the land area of Chilean Patagonia (from Reloncaví sound to the Diego Ramírez islands) is protected, which represents the majority of land area under protection in the country [40] and 86.4% of the National System of Protected Areas (in Spanish SNASPE) in Chile. Chilean Patagonia is also home to the three largest protected areas in the country: Bernardo O'Higgins National Park, Alberto de Agostini National Park and Kawésqar National Reserve.

The science of biological conservation offers tools to analyze the different actions and options that can be carried out in the territory, in response to the protection policies and international commitments subscribed to by countries. One of these approaches is systematic conservation planning, which facilitates the step-by-step determination of conservation goals and objectives through optimal solutions in a transparent and replicable process [17, 32]. Systematic planning seeks to represent previously defined conservation targets (e.g. biodiversity, ecosystem services) through the best possible solution that fulfills the established goals. The definition of conservation targets can be through “surrogates” that represent different dimensions of biodiversity, which due to lack of data or the impossibility of collecting information, cannot be considered in the planning process. The resulting solutions then permit the most strategic approach to incorporating new protected areas to the protected area system so as to minimize the associated costs (e.g. land suitability and value) and surface area involved.

The natural environment in Chilean Patagonia is a unique landscape in the world, which due to its pristine characteristics must be effectively and efficiently conserved and protected. The evaluation of the current representativeness and the identification of priorities for the protection of terrestrial ecosystems is a fundamental exercise for the definition of conservation priorities for the natural biota present in Chilean Patagonia.

2 Scope and Objectives

The general objectives of this chapter are: (i) to determine if there are gaps in the representation of terrestrial ecosystems in Chilean Patagonia; (ii) to identify priorities for the protection of terrestrial ecosystems and species of flora and fauna; and (iii) to identify opportunities to improve the representation of the diversity of terrestrial ecosystems in the SNASPE across Chilean Patagonia, which is defined as the area between Reloncaví Sound and the Diego Ramírez islands (41° 42′ S 73° 02′ W; 56° 29′ S 68° 44′ W).

The first stage included a review of the existing literature on representativeness analysis (terrestrial ecosystems and species) and spatial prioritization, both nationally and for Chilean Patagonia. This review included analysis of a database of scientific articles [2], as well as articles, reports and theses of national coverage. The second stage consisted of the application of a spatial prioritization method, including species and ecosystems as conservation targets. Subsequently, an analysis of the representativeness of terrestrial ecosystems and species of flora and fauna present in Chilean Patagonia was carried out. Finally, recommendations are presented for the adequate conservation of the ecosystem processes and services within the SNASPE. These also indicate actions necessary for the adjustment and improvement of the system of protected areas in Chilean Patagonia.

3 Methods

3.1 Literature Review

Three search strategies were carried out with the objective of compiling the available literature related to the current representativeness and conservation gaps in the protected areas of Chilean Patagonia. The first strategy involved searching for references using the search terms “conservation”, “gaps”, “priorities”, “representativeness”, “protected areas”, “ecosystems” and “biogeographic regions”. As a second search strategy, Google Scholar was used to repeat the previous search arguments, adding the words: Chile and Patagonia and Aysén and Magallanes. Finally, the topics used in the previous search were consulted in the “ISI web of knowledge” search engine, which was extended to include reports, theses and books.

3.2 Assessment of Protection Gaps and Priorities

3.2.1 Spatial Prioritization Analysis

A spatial prioritization analysis was performed [15] considering two types of conservation targets: terrestrial ecosystems (vegetation belts) and species (flora and fauna). The objective was to determine a set of priority areas to evaluate the gaps in representativeness of the diversity of terrestrial ecosystems in Chilean Patagonia, and to identify opportunities to strengthen the representation of terrestrial biodiversity of the SNASPE in Patagonia. Ecosystems and species were selected as conservation targets because they represent the two levels of biodiversity with the greatest amount of available information. Other types of targets, such as those related to ecosystem processes, were not considered in this chapter. Spatial prioritization was carried out using the Zonation software [26]. This software applies a prioritization meta-algorithm according to different cell removal rules that minimize the marginal loss of the total landscape [26].

The vegetation belts of Luebert and Pliscoff [16] were used as descriptors of terrestrial ecosystems in Chilean Patagonia. This proposal has been defined by the Ministry of the Environment (in Spanish Ministerio de Medio Ambiente, MMA) as the official classification of terrestrial ecosystems in Chile. Vegetation classification systems have been widely used as surrogates for ecosystems, because vegetation is an integral element of the biophysical attributes of an area [3]. Species Distribution Models (SDMs) were used to analyze the set of flora and fauna species present in Chilean Patagonia. The SDMs are empirical models that relate records of occurrences with predictive environmental variables, with the purpose of modeling the distribution of species or set of species in geographic space [12].

A photo of a man trolling through a dried grassy field, with an expanse of mountains in the distance.

Choique post-Roballos border crossing, Patagonia Park, Aysén Region. Photograph by Jorge López

Occurrence records of vascular flora species in Chilean Patagonia were compiled, based on information from herbaria in Chile (Universidad de Concepción, Museo Nacional de Historia Natural, Herbarium de la Facultad de Ciencias Forestales y de la Conservación de la Naturaleza, Universidad de Chile). Additionally, the vascular flora database compiled by Scherson et al. [37] was considered. If the locality of the herbarium record did not have geographic coordinates, these were assigned manually. Occurrence records were considered for four groups of fauna: mammals, reptiles, amphibians and birds. This information was obtained from the report by Marquet et al. [18] and from the specimen database of the Chilean MMA (Global Environmental Inforamtion Facility-Chile). Records with geographic coordinates for all taxonomic groups were corrected for locality inconsistencies, duplicates and synonymies.

Temperature and precipitation data used as environmental predictor variables to develop SDMs. The climatic basis for current conditions was obtained from the repository published by Pliscoff et al. [31], from which bioclimatic surfaces with a spatial resolution of 1 km × 1 km were used, representing a 50-year period (1950–2000) for southern South America. The “Maxent” software was used to model the species distributions of all taxonomic groups [7, 29]. To avoid spatial correlation of occurrences, records that were less than 4 km apart were removed, and those species with at least 10 records were selected. The final database for Chilean Patagonia is composed of 18,511 records for flora and fauna. The breakdown by taxonomic group is presented in Table 1 and its spatial distribution in Fig. 1.

Table 1 Number of species, relationship to national diversity by taxonomic group [23] and occurrence records used for SDM
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Fig. 1
Five maps of Chilean Patagonia highlight the presence of vascular flora, birds, mammals, amphibians, and reptiles.

Database by taxonomic groups present in Chilean Patagonia

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The less correlated bioclimatic variables were selected as predictor variables for the SDM. The selected variables were: mean annual temperature, seasonality of temperature, maximum temperature of the warmest month, annual precipitation and seasonality of precipitation. The records of occurrence of each species were partitioned into percentages of 80% to train the model and 20% to generate the tests of the final models by species. The SDMs were estimated according to the probability of occurrence of each species, and binary SDMs were estimated (presence-absence of a species), applying the sensitivity–specificity threshold. The modeling was carried out considering the limits of Chile, and then restricting the results to the study area defined for Chilean Patagonia.

Species richness of flora and fauna was estimated by summing the distributions of each taxonomic group modeled with SDM. These were grouped into the total species richness per taxonomic group (plants, mammals, amphibians, reptiles and birds), and the richness of threatened species per taxonomic group. The classification of species of the Ministry of the Environment of the Chile [24] was used for the definition of threatened species, up to process n°16.

For the spatial prioritization in Chilean Patagonia, we considered as input data the vegetation belts present in the area (36) and the distribution models of the 844 species of flora and fauna, from which four scenarios were generated (see Table 2). The aim for total species richness is to identify the areas with the greatest diversity of the five selected taxonomic groups, using the core-area (CA) prioritization method. By considering the diversity of threatened species separately, we seek to prioritize the areas in which these species are represented, in this case using the additive benefit function (ABF) prioritization method. Finally, scenarios were analyzed to identify the contribution of SNASPE areas to fill gaps in representation. A prioritization was first carried out for the entire area of Chilean Patagonia, and then the exercise was repeated considering only the areas outside the SNASPE (Table 2).

Table 2 Prioritization scenarios for terrestrial species and ecosystems in Chilean Patagonia
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The final result of the prioritization is a percentage ranking of the total area of Chilean Patagonia, from which the 17% with the highest priority was selected, following the protection target defined by the Convention on Biological Diversity (CBD) for terrestrial ecosystems [5]. Finally, the spatial correspondence between the highest priority areas and those belonging to the SNASPE was analyzed using the ArcGis 10.6 Geographic Information System [8].

3.2.2 Representativeness Analysis of Terrestrial Ecosystems and Species of Flora and Fauna in Chilean Patagonia

The percentage of surface area protected by the SNASPE in each of the vegetation belts of Luebert and Pliscoff [16] present in Chilean Patagonia was estimated by superimposition mapping. The SNASPE boundaries were obtained from the MMA’s national registry of protected areas [25]. The total area of each ecosystem was estimated by defining the area of the vegetation belt and the remaining area of vegetation. This remaining area is obtained from the anthropic land use categories (agricultural, urban and forest plantation areas) defined in the Cadastre of Native Vegetation Resources of the National Forestry Corporation [4], in which regional updates were used for Los Lagos (2013), Aysén (2013) and Magallanes (2005). The estimate of the percentage of protected area was calculated as the ratio between the total area of the ecosystem and the remaining area.

The Aichi target, in addition to setting a target of 17% protection of terrestrial ecosystems [5], considers all levels of biodiversity organization, so it is also relevant to analyze the representation of flora and fauna species present within the network of protected areas. The SDMs were analyzed in two groups: flora (vascular plants) and fauna (mammals, birds, reptiles and amphibians). Finally, the species richness of the two groups was grouped into deciles and the surface areas within the SNASPE areas were calculated.

4 Results

4.1 Bibliographic Review

Twelve documents referring to the terrestrial and marine environments of Chilean Patagonia were identified and reviewed (Table 3). These documents presented either representation analyses or gaps in the conservation of terrestrial environments, both for Chilean Patagonia and for the whole country. Ten of the documents analyzed address the terrestrial system and two address the marine system. The documents that analyze the terrestrial system are primarily national technical reports [34], Geobiota [11], only one scientific article focuses on Chilean Patagonia [19]. The rest of the studies analyzed the identification of conservation priorities and the analysis of the representativeness of the SNASPE, also considering other categories of protection (e.g. private conservation initiatives, nature sanctuaries, protected national assets).

Table 3 Documents identified in the literature review
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Two approaches were to define terrestrial ecosystems. The first uses vegetation as a proxy of terrestrial ecosystems; this is the case of Luebert and Pliscoff's vegetation belts [27, 30, 39]. The second uses the classification of ecoregions to assess national protection gaps [21, 38, 39]. Two studies considered other conservation targets to evaluate their representation in the SNASPE; Tognelli et al. [41] established conservation priorities based on the distribution of terrestrial vertebrates and Durán et al. [6] used the ecosystem services approach.

4.2 Assessment of Protection Gaps and Priorities

4.2.1 Spatial Prioritization Analysis

The first prioritization scenario considered terrestrial ecosystems and the taxonomic groups modeled (plants, amphibians, mammals, reptiles and birds). The results of this scenario suggest that the greatest concentration of areas of importance is in the northern sector of Patagonia (between 41° and 47° S); specifically, the areas of highest priority are concentrated in the area of the Palena Province and south of Chiloé Island. Other priority zones are identified in the interior of the Aysén Region and in the forest-steppe transition zone in the Magallanes Region.

The results for the second scenario, which considers the distribution of threatened species, presented differences with respect to the first scenario due to the fact that the priority area within the Aysén Region is increased, including the western zone of the archipelagos in the Southern Ice Fields and expanding the priority areas in the Magallanes Region. Excluding the current areas of the SNASPE (third and fourth scenarios) did not modify the results substantially, and the same priority areas shown in the two previous scenarios were maintained (Fig. 2).

Fig. 2
At the top are four maps of Chilean Patagonia that highlight the prioritization of scenarios 1 to 4 for the terrestrial ecosystem based on ranking. Below are 4 maps for prioritizing threatened species in scenarios 1 to 4.

Prioritization of scenarios analyzed in Chilean Patagonia. Above: scenarios prioritized by ranking. Below: indicates the 17% of greatest importance (protection goal)

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4.2.2 Analysis of the Representativeness of Terrestrial Ecosystems and Species of Flora and Fauna

The analysis of the representativeness of terrestrial ecosystems allows us to identify the current gaps in the SNASPE (Fig. 3) and the representation of the different percentages of diversity of flora and fauna species (Fig. 4). The results show an imbalance of current protection between the ecosystems present in the archipelago zone (which are over-represented) versus the interior-south zone of Chilean Patagonia (which are under-represented), and are located on the border with Argentina (Fig. 3B). The archipelago zone has moorlands and evergreen forest ecosystems and the interior-south zone has steppe and deciduous forest ecosystems (Fig. 3B).

Fig. 3
2 parts. A. A map of Chilean Patagonia highlights the areas of different vegetation formations. B. A double-bar graph plots values for protected and regional areas.

Representativeness of terrestrial ecosystems in Chilean Patagonia. A Shows the distribution of vegetation formations (VF); red border indicates ecosystems below the 17% protection target. B Bar graph showing the protected area versus the total regional area of each VF. Ecosystems below the 17% target are indicated by the red line

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Fig. 4
A and B are maps of Chilean Patagonia that highlight the species richness of flora and fauna, respectively. C is a horizontal bar graph that plots the percentage of species richness versus the number of protected areas.

Species representativeness in Chilean Patagonia. A Flora species richness. B Fauna species richness. C Bar graph shows the representation of percentages of flora and fauna richness versus the number of SNASPE units

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The analysis of species representativeness (Fig. 4A, B) shows that the highest concentrations of richness for both flora and fauna are found in the northern zone of Chilean Patagonia between 41° and 44° S. These areas of greatest richness are located in Chiloé in the case of flora and in the province of Palena for fauna. The SNASPE adequately represents the areas of greatest floral richness, however, for fauna, only areas with richness less than 30% are represented (Fig. 4C), indicating an under-representation of the areas where fauna is concentrated in Chilean Patagonia.

5 Discussion

The results obtained regarding the representativeness of terrestrial ecosystems in Chilean Patagonia allow us to determine some key elements for discussion. Although the identification of protection gaps in deciduous forest-steppe and steppe transition ecosystems had already been reported previously in representativeness analyses [16, 30], one of the contributions of this chapter is to demonstrate that it is possible to use both the distribution of species and terrestrial ecosystems to prioritize areas for conservation, including or excluding the SNASPE.

The distribution of flora and fauna species had not been evaluated for Chilean Patagonia using a prioritization approach, but there was a history that the current protected areas did not consider the representation of the variety of existing ecosystems, concentrating only on some types of ecosystems (e.g. moorlands, evergreen forest) [39]. For terrestrial ecosystems, we worked with the most detailed spatial definition currently existing for Chile (vegetation belts), but due to the focus of this work, certain types of ecosystems have been excluded (e.g. azonal ecosystems).

The main information gaps detected in this chapter are the lack of data to analyze ecological processes and threats to biodiversity resulting from human activities. To improve the approach developed in this chapter, it is necessary to consider different cost categories (socioeconomic, biodiversity) in an integrated manner, in order to meet conservation goals [20]. Also, land-use cover needs to be included to model the current distribution of ecosystems.

The analyses in this chapter considered the potential distribution of each ecosystem, which does not affect the results presented since the areas with the greatest human intervention in Chilean Patagonia are small (in surface area) compared to other intervened areas in Chile. If the analysis had considered anthropically intervened areas, the results would probably have been different for the transition zone between the deciduous forest and the steppe, which is one of the most disturbed areas in Chilean Patagonia [14]. New databases of flora and fauna occurrences are also needed to obtain more robust SDMs, as well as to include new species that were not contemplated in this study. This aspect is especially relevant for fauna, where the available databases do not have representative information for some taxonomic groups, for example, birds and mammals in Chilean Patagonia.

In the literature there are national and global methodological approaches that could complement the approach of this work. For example, Durán et al. [6], developed a mapping of ecosystem services at the national scale using a prioritization approach similar to the one proposed in this chapter. At the global scale there is greater availability of mapped information on ecosystem services (e.g. carbon sequestration, tourism and recreation, among others) relevant to develop future regional prioritization exercises [13].

6 Conclusions and Recommendations

The definition of the coastal-terrestrial interface and the generation of adequate data that allow both systems to be analyzed in an integrated manner should be the focus of research in the short term. The literature review conducted for this chapter found only one study that prioritized both marine and terrestrial systems at the national level, and this defined separate conservation targets for each [21]. With regard to the representativeness of terrestrial ecosystems, the greatest gaps in representation were identified in steppe ecosystems and in the deciduous forest-steppe transition, both of which are located in the Aysén Region and in Magallanes. The diversity of fauna species is not adequately represented in the SNASPE, which is currently concentrated in areas of lower richness. This situation is different for flora, where the areas of highest species richness have greater representation in the SNASPE.

The prioritization scenarios allowed us to analyze the patterns of distribution and richness of flora and fauna in Chilean Patagonia. The results indicate that the SNASPE does not represent the 17% of areas with the greatest importance (Fig. 2). Priority areas were identified in the insular Chiloé and Palena province (Los Lagos Region), and in the inland area of the Coyhaique and General Carrera provinces (Aysén Region), Última Esperanza province, Magallanes and Tierra del Fuego (Magallanes Region).

The following is a set of recommendations aimed at different stakeholder groups, such as decision-makers, scientists and others.

  • Short-term recommendations (1–2 years). (i) Conduct a new terrestrial prioritiztion analysis using updated information generated by publications and repositories of global biodiversity and ecosystem services information. The study should consider other protected area categories (e.g., private conservation initiatives) in the representativeness analysis. The level of administrative management of protected areas should also be considered, as it is possible that areas identified as priorities in future analyses may not have effective protection in conservation category areas. It is also important to analyze the costs of conservation in the prioritization analysis, in case priority areas are not represented in protected areas. The new analysis should include researchers from Chilean Patagonia. (ii) Develop a participatory and open process for the definition of conservation objectives and goals, in order to be included in the next prioritization exercises. There are studies carried out in the marine system [22, 43] which could be a methodological guide to be replicated in the terrestrial system.

  • Medium-term recommendations (up to 5 years). (i) Develop a prioritization analysis of the marine-terrestrial complex that accounts for the coastal interface, for example, considering runoff or glacial dynamics models; (ii) develop species distribution models (SDMs) with marine-terrestrial climate data in coastal zones in an integrated manner. This would be relevant to analyze when considering future scenarios and establishing conservation priorities [1]; (iii) re-evaluate the gaps in ecosystem representation (terrestrial and marine) by the incorporation or removal of protected areas and reserve systems.

  • Long-term recommendations (>5 years). Develop a system for monitoring the system of terrestrial and marine protected areas at different levels: ecosystems, species, processes and ecosystem services.