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A biodiversity Vision for the upper Paraná Atlantic Forest Ecoregion

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Setting biodiversity conservation goals

We have set four basic goals for this Biodiversity Vision to achieve conservation results in the Upper Paraná Atlantic Forest ecoregion. The four goals are based on conservation biology principles, and include:

  1. The conservation of blocks of natural forest large enough to be resilient to short-term and long-term environmental changes

  2. The maintenance of viable populations of all native species in their natural patterns of abundance and distribution, and with the genetic diversity necessary to meet environmental challenges

  3. The maintenance of healthy ecological processes and selective factors such as disturbance regimes, hydrological processes, nutrient cycles, and biotic interactions, including predation

  4. The representation of all native biological communities and seral stages across their natural range of variation within a Biodiversity Conservation Landscape.

Crafting the Vision

Underlying the Biodiversity Vision is a series of complex analyses aimed at designing a Biodiversity Conservation Landscape that will accomplish the conservation goals described above. During the past three years, WWF has led a tri-national participatory process involving more than 30 local organizations representing multiple sectors and disciplines. Many of these organizations4 provided information and data critical to produce this Biodiversity Vision for the time frame and geographic scale necessary to conserve the Upper Paraná Atlantic Forest Ecoregion’s biodiversity.

For the analyses we used various overlays of maps representing the distribution of the different biological and socio-economic variables. A Geographic Information System provided a critical tool for conducting the analyses and visually describing different layers of information in various maps. Three separate but interdependent analyses were critical to arrive at the final Biodiversity Conservation Landscape:

The first step involved the identification of individual landscape units5. Given the lack of complete or sufficient biological information available to define and map all ecological communities, we used climatic, altitude, and topographic information as proxies for developing a biological model. Using these three layers of information, we identified 18 separate landscape units.

The second step involved the identification of native forest fragments with the highest potential for achieving conservation goals. For this fragmentation analysis, we used a map of forest fragments obtained from satellite images. We ranked forest fragments according to a Fragment Importance Index developed to indicate the relative contribution of forest fragments to biodiversity conservation. The index was based on four variables: fragment size, fragment size after excluding a buffer zone6 of 500 m (an indirect measure of edge effects, see Box 4), distance to nearest fragment, and altitudinal range within the forest fragment.

The third step was a threats and opportunities analysis, where the objective was to map areas that represent critical threats and important opportunities for biodiversity conservation. Land use information provided a critical basis for assessing conservation opportunities and threats. The threat variables used in our analysis included: distance to cities, agriculture, cattle raising, and rural population density. Opportunity variables that were used included: the distance from a strictly protected area, the proximity to a river (assuming that rivers in this ecoregion constitute potential biological corridors), and zones of planned conservation. Variables were weighted according to their relative impact on biodiversity conservation.

We analyzed the current status of forest cover and representation of the different landscape units within the protected area system using the landscape units map in combination with the forest fragments map and the protected areas map. This gave us an idea of how well represented each landscape unit was in the actual landscape, and guided decisions on how to improve representation of those underrepresented landscape units in the final Biodiversity Conservation Landscape. Combining the fragment importance index map with the threats and opportunities map, we constructed a biodiversity conservation potential map that illustrates where the areas with the highest biodiversity conservation potential are located in the ecoregion. Using this biodiversity conservation potential map as the basic layer of information, we defined a Biodiversity Conservation Landscape. Expert opinions and socio-political viability of certain decisions where also taken into account when outlining the Biodiversity Conservation Landscape. This process is summarized in Fig. 32.

Refining the final Biodiversity Conservation Landscape, involved a series of logical analyses and decisions that we explain in a simplified manner here. First, using the biodiversity conservation potential map as a guide, we identified large native forest blocks (>10,000 ha) to constitute Core Areas (see definition below). These are the forest fragments that may sustain the whole life cycle of a jaguar, which we used as our umbrella species7. Next we identified Main Corridors to connect Core Areas. Lastly, smaller areas of relatively high conservation value, surrounded by secondary corridors, were included to increase representation of landscape units and associated biodiversity within the final design of a biodiversity conservation landscape.

Our Vision in a map

Our Biodiversity Vision is a Biodiversity Conservation Landscape that spans the three countries, with adequate space for wildlife set aside from human activities to ensure that critical biodiversity conservation goals are met. The implementation of this Vision will depend on the participation of many sectors and the coordination of activities across the borders of the three countries.

The resulting Biodiversity Conservation Landscape is composed of three main types of areas:

The Core Areas are the blocks of well-preserved native forest large enough to be resilient to threats that cause biodiversity loss. These are the most biologically important and strategic zones for conservation, either public or private. Each Core Area should be managed to maintain an area of continuous native forest large enough for the life cycle of wide ranging species such as jaguars and white-lipped peccaries. Core Areas should be managed under strict protection and human activities should be reduced to a minimum. Core Areas should be connected to other Core Areas through a network of corridors to meet our biodiversity conservation goals.

The Biological Corridors are relatively narrow areas of native forest, either natural or restored, that connect large forest patches, either Core Areas or Sustainable Use Areas. The Biological Corridors would allow the movement of the wildlife and sufficient genetic interchange among Core Areas to maintain viable populations.

The Sustainable Use Areas are large areas that function as buffers and connections surrounding the Core Areas, other critical conservation areas under strict protection, and the biological corridors. They maintain healthy ecological processes and environmental services in combination with environmentally friendly economic activities.

We have also identified areas that are important for the development of river basin management and conservation programs as well as areas where we need to develop finer-scale land use planning to appropriately create and implement critical Biological Corridors.

Figure 36 depicts the resulting Biodiversity Conservation Landscape. Due to the lack of opportunities for biodiversity conservation and the lack of forest fragments with sufficient conservation value, some landscape units are not represented in the final Biodiversity Conservation Landscape. However, this Biodiversity Conservation Landscape will ensure the conservation of large and resilient blocks of native forests, where viable populations of umbrella species and healthy ecological processes, including predation by top predators, will be sustained. Both the Biodiversity Conservation Landscape and the Biodiversity Vision will continue to be refined over time as additional studies are undertaken and new information becomes available.

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