Preparation of Map Database for Analysis of Paraguayan Atlantic Forest Fragmentation

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1 Nicholas Gengler DCP 2001 Fall 2018 Final Project Report Preparation of Map Database for Analysis of Paraguayan Atlantic Forest Fragmentation Background The Atlantic Forest is one of the most biodiverse, yet threatened ecosystems in the world (Myers et al, 2000). Separated from the Amazon by the savanna-like plains of the Cerrado, it once covered over 1,000,000km² from the equator in Brazil to temperate central Paraguay. This unique ecosystem supports uncommonly high amounts of endemic plant and animal species, meaning they are found there and nowhere else in the world. Interesting and noteworthy species include jaguar, tamarin monkeys, bell birds, and harpy eagle. In addition to unique biodiversity, the Atlantic Forest generates the world s largest fresh water aquifer, provides medicinal and commercial plants, regulates the local climate, and prevents the erosion of highly fertile soil. Despite the value of the Atlantic Forests, over the last years ~90% of its original extent have been deforested (Fundación Vida Silvestre and WWF, 2003; Fundación Vida Silvestre and WWF, 2017). This deforestation was driven mostly by intensive production of soy bean. Largely the same pattern of deforestation for soy beans occurred in Paraguay specifically (DaPonte et al, 2016), leaving the country with just 9% of its original amount of Atlantic Forest. This deforestation occurred haphazardly with little to no planning or coordination, resulting in the remaining 9% being distributed across the country as very small patches of forests between farm land, rather than together as one large chunk. This sort of pattern is called fragmentation,

2 and can be especially bad for tropical wildlife (Thornton et al; 2011). It can create a situation were small forest patches can only support a few individuals of a given species, causing genetic inbreeding and the inevitable die off of all the animals in that patch. This can lead to a landscape full of small empty forests (Ribon et al, 2003). One way to help prevent these local extinctions is by providing animals with corridors between the forest patches to allow them to disperse and exchange genes (Paolino et al, 2018). Preserving and restoring these corridors have been a high priority for conservation efforts in the Atlantic Forest. However, it is often difficult to know if these efforts are effective and if animals use the corridors. Many factors could lead to one corridor being able to facilitate movement, and not another. One way to verify if corridor function is through translocation experiments, where animals are collared and moved to a patch connected by a certain type of corridor to see if the animal uses that corridor (Castellon et al, 2006). A model area to conduct such a study would be the Itaipú Biosphere Reserve. Study Area The Itaipú Biosphere Reserve (IBR) was designated by UNESCO in It corresponds to roughly 1,000,000ha around the principle Paraguayan waterways feeding the Parana river north of the Itaipú hydroelectric dam. When the dam was created, Itaipú was required to form forest reserves to compensate for the land flooded by their reservoir. They did so with seven private conservation areas bordering their reservoir, totaling 38,000ha (1,168-13,744ha, average 5,463ha). Additionally, to protect their dam and reservoir from silt runoff, they maintain a ~50m wide strip of forest around the whole reservoir, which likely facilitates the movement of animals between the forest reserves. Other rivers and streams in the IBR have similar thin protector forests creating an extensive network of large forest patches, small forest patches, and corridors.

3 The IBR covers part of two Paraguayan departments, Alto Parana and Canindeyú, and large parts of about ten municipalities. Most of the land outside the seven private forest reserves are privately owned soy plantations. Paraguayan forest code stipulates that all rivers and streams must be surrounded by ~50m of forest, and also that large properties must maintain part of the land as forest reserves. These two regulations create some degree of forest cover outside of Itaipú s main private reserves. Roughly 17.5% of the IBR is under forest cover of any type. Objectives The overall purpose of this project is to create a map database suitable for analysis of forest fragmentation, animal movement patterns, and habitat connectivity in the IBR. Many GIS data are available for Paraguay, however little of it is organized or formatted in such a way as to be useful for study of habitat connectivity in this specific region. As such, in order to meet the overall objective: 1. Useful GIS data of relevant information must be collected 2. These data must be formatted/standardized 3. These data can begin to be analyzed Once accomplished, researches will be able to utilize this map database in a number of ways to plan and conduct research in the area. Methodology Useful GIS data was collected from associates from two Paraguayan organizations: Itaipú Binational, and World Wildlife Fund Paraguay. Itaipú has its own team of GIS specialists that work on a number of tasks related to the management of the dam. This work mostly relates to hydrology, however Itaipú does manage its private forest reserves and protector forest strip and therefore has numerous layers and maps relevant to ecology and connectivity. I requested and was granted access to their data repository: This repository contains 154 GIS layers, ~20 of which I identified as potentially useful to my project. Ultimately I used four for the final project: hydrology, IBR area, Itaipú private forest reserves, and reservoir area. World Wildlife Fund Paraguay also has its own small team of GIS specialists, mostly tasked with monitoring the country s rate of deforestation. As such, they possess numerous (>500 layers) of information related to Paraguayan environment, infrastructure, and geography. I was personally transferred these layers by a colleague in the WWF GIS team. Of this database I ultimately choose two layers to include in the final project: roads of Paraguay, and 2015 forest cover of Paraguay. Once these data were obtained they had to be formatted and standardized before they were all brought together into a unified.mxd file. Immediately it was noticed that many of the layers were projected differently. To ensure accuracy and aid further editing I projected all layers to the most common one between them: WGS.1984.UTM.zone.21S. Once this was done many

4 layers had to be reduced in size to the extent of the IBR study area. To do so I used the clip function in ArcMap using the IBR area layer as the template. Once this was done many of the layer attribute tables still contained many unnecessary or even empty fields that slowed down the ArcMap program. I eliminated all empty fields or field unnecessary to analysis of connectivity. Once the unnecessary fields were eliminated, some fields needed to be generated in order to make analysis possible. In particular, the 2015 forest cover layer needed substantial modification. First, the layer contained all geometrically independent forest patches together as one single feature. This resulted in the data attribute table containing only one row referring to forest cover of the entire country as a whole. For a study of connectivity, analysis at the patch level is required, making this format for forest cover unsuitable. To remedy this, I used the explode function in ArcMap. This identified and separated each geometrically independent unit into its own feature. This provides exactly the format needed to calculate important aspects such as patch area, perimeter, and centroid. In order to begin to populate this attribute table with these useful data I used the calculate geometry feature in ArcMap to create fields for patch area (in hectare) and perimeter (in meters). A cursory review of the patch size revealed some irregularities. Namely that the explode function resulted in a few very slightly connected, yet functionally independent patches being connected when they should not be. To remedy this, I used the cut polygon tool to split the patch polygons in the areas of minor connection and recalculated area and perimeter. This process led to a much more ecologically accurate definition of patches. Finally, I generated a field for river and stream length (in meters) for the hydrology layer. Results Collecting, formatting, and bringing together these layers resulted in a map of the IBR containing all the major geographic aspects important to studies of habitat connectivity.

5 Hydrology of IBR

6 Forest cover of IBR

7 Itaipú private forest reserves

8 Conclusion Preparation of the above maps have revealed a number of characteristics about the landscape of the IBR. One insight is that forest cover is highly correlated with rivers and streams. A close look reveals that the majority of forest cover not part of Itaipú s reserves directly borders waterways. This indicates that with few exceptions a great amount of forest cover in the IBR is riparian protector forest, established primarily to protect waterways from evaporation and agricultural runoff, and may not serve particularly well for supporting wildlife. Analysis of forest cover also reveals that there are 4,754 forest patches in the IBR, at an average of 33ha when outliers were removed. While 33ha may seem like a lot of land, it is actually insufficient to independently support self-sustaining populations of many species of wildlife (Fundación Vida Silvestre and WWF, 2003). This highlights the importance of connectivity to maintaining biodiversity and biomass in the region. Without at least some degree of connectivity the vast majority of patches would eventually be devoid of wildlife. These insights however come from only the most cursory of analysis of the landscape. The real value of this database is that it can be further modified and used for more detailed evaluations based on ecological theory. Programs such as FRAGSTATS or R can quantifiably compute measures of patch isolation, forest core area, eigenvector analysis, and landscape resistance; all measures of extreme value for conservation planning and management. To do so may require further work, and was beyond the scope of this project. However, by creating this map database the important first steps have already been taken. Literature Cited Castellon, T., Sieving K An Experimental Test of Matrix Permeability and Corridor Use by an Endemic Understory Bird. Conservation Biology Volume 20, No. 1, Da Ponte, Emmanuel; Roch, Marthe; Leinekugle, Patrick; Dech, Stefan; Cuenzer, Claudia. (2016). Paraguay s Atlantic Forest cover loss-satellite-based change detection and fragmentation analysis between 2003 and Applied Geography, 79 (2017) ESRI ArcGIS Desktop: Release 10. Redlands, CA: Environmental Systems Research Institute. Fundación Vida Silvestre, WWF. (2017). State of the Atlantic Forest: Three countries, 148 million people, one of the richest forests on Earth, 148. Fundación Vida Silvestre, WWF. (2003). WWF BAAPA Biodiversity Vision. Myers, N., Mittermeier, R. A., Mittermeier, C. G., da Fonseca, G. A. B., & Kent, J. (2000). Biodiversity hotspots for conservation priorities. Nature, 403(6772),

9 Thornton, D. H., Branch, L. C., & Sunquist, M. E. (2011). The influence of landscape, patch, and within-patch factors on species presence and abundance: A review of focal patch studies. Landscape Ecology, 26(1), Ribon, R., Simon, J. E., & Mattos, G. T. (2003). Bird extinction in Atlantic Forest fragments of the Viçosa region, southeastern Brazil. Conservation Biology, 17(6), Paolino, R. M., Royle, J. A., Versiani, N. F., Rodrigues, T. F., Pasqualotto, N., Krepschi, V. G., & Chiarello, A. G. (2018). Importance of riparian forest corridors for the ocelot in agricultural landscapes. Journal of Mammalogy, 99(4),