"Work Package 1 â€“ Análisis of Deforestation"
Work Package 1 – Analysis of Deforestation 15 January 2003 PLANNED ACTIVITIES 2002-2003 (Text in italics represent notes taken from presentations in Oaxaca in December, 2002) 1) Universidad Austral de Chile (Contact: Cristian Echeverría) Cristian Echeverría is working on his Ph.D. thesis (University of Cambridge) on the fragmentation and deforestation and its effect on the diversity of woody species in the Maule and Lake Regions in Chile. This study has the following objectives: 1. To analyse the spatial and temporal patterns of deforestation in selected counties in the Maule and the Lake Regions (Regions VII and X) 2. To identify and analyse the determinant factors that explain the temporal changes in forest cover in both study areas. 3. To develop predictive models spatially explicit. Methods: The analysis will be done from Landsat images of the following dates: VII Región 1975, 1990 y 2000. X Región: 1976, 1985 y 1999. The images have been already analysed with the PCI geomatic software, for geometric, atmospheric and topographic correction (September, done in collaboration with Partner 8 in Alcalá de Henares). After corrections, the images will be classified according to different land use/ land cover. The fragmentation will be analysed through the study of the spatial configuration of forest stands, and the factors that explain deforestation. With this information for the changes occurred between 1975 and 2000 for Region VII and 1976-1999 for Region X, a spatially explicit predictive model will be developed. Studies done by other partners Within WP 1, Luis Cayuela, a Ph.D. student from U. de Alcalá de Henares (Partner 8) will carry out a fragmentation and deforestation study in Chiapas, using similar methods to those being used in Chile. This study will imply a close collaboration among Partners 2, 8 and 6 (Colegio de la Frontera Sur, ECOSUR). Kerry Wilson a Ph.D. student from University of Melbourne is conducting her thesis “Logistic model for the identification of vulnerable areas to deforestation in Chile”, working with Adrian Newton (Partner 1), and with the collaboration of Partner 2. Milestones - Correction of Images for the study areas in Chile - Analysis and classification of images - Development of GIS data base with land use-land cover categories and environmental variables Deliverables - GIS Data base on a CD-ROM Map of forest cover cross-time Acquired LANDSAT ETM mages from UNEP. For two regions of Chile; currently being analysed by UAL & UACH for three periods: 1975-76 1985-86 1999-2000 They plan to model fragmentation and express the need to discuss how to do this with the best approach possible. To do this we need to liaise between partners regarding development of method. 2) ECOSUR (Contact: Dr. Susana Ochoa) En cuanto al uso del SIG en ECOSUR se prevee la participación de la Dra. Susana Ochoa Gaona desde la Unidad Villahermosa de ECOSUR, con el apoyo de algún becario de licenciatura o posgrado que pueda realzar el trabajo de campo necesario en acuerdo con el personal de la Unidad San Cristóbal en Chiapas. Ella ha establecido contacto con el grupo de UAL para definir los detalles de su colaboración con el uso de SIG y teledetección. De ello ha dado cuenta el líder de UAL en su resumen de actividades propuestas. El objetivo principal es calcular las tasas de deforestación, los procesos implicados y los patrones obtenidos entre los años setenta y el 2000 en la totalidad del área de estudio en Chiapas, a partir del uso de varias imágenes de satélite y posiblemente fotografías aéreas. Susana Ochoa ya ha publicado dos antecedentes importantes para regiones más pequeñas que las implicadas en el trabajo propuesto (Ochoa-Gaona y González-Espinosa 2000 y Ochoa-Gaona 2001). Productos: mapas de usos del territorio, mapas de deforestación, un manuscrito publicable y una tesis de licenciatura o maestría en ciencias. LANDAT MSS images procured and analysed for 1970, 1980, 1990, 1996. Work already done but will continue under this project. The analyses to be included are an analysis of fragmentation it’s causes including socio-economic factors. Patterns will be documented during 1974, 1995, and 2003. The study will focus on mountains of north of Chiapas although there is concern that Los Altos should be included as well since this is were many study sites are located. They need to get hold of new maps from INEGI including DEMs (20 m resolution). ECOSUR is currently working on creating land use mapas from LANDSAT 2000 images for Los Altos – Duncan Golicher. 3) Instituto de Ecología, A.C. (Contact: Dr. Robert H. Manson) We have acquired previously classified land use / vegetation maps based aerial photographs and satellite images (INEGI, CONABIO, Instituto de Geografía, UNAM), from different years 1980 and 1996 (scale 1:1,000,000) as well as 1984 and 2000 (scale 1:250,000). We will be using the higher resolution maps for estimates of deforestation on a regional scale but finer scale analysis of fragmentation is probably not possible with these maps. Environmental and demographic data will be collected from the National Censuses of 1990 and 2000 (INEGI). One possible constraint is the availability of up to date and fine-scale images with which to work (the most recent photos we have are from 1993; scale 1:250,000). We are currently negotiating with various investigators at the Instituto de Ecología, A.C. and state and federal agencies about the possibility of collaborating in the purchase of 1 m2 resolution color images from the IKONOS satellite. These images cost $US 20.00 per km2 with a minimum purchase of 100 km2 and come with the spectral bands necessary to perform a supervised classification of the vegetation in the region. These or similar images will be orthorectified and georeferenced using ARCINFO and ARCVIEW software. During the first six months, students and collaborators will use handheld GPS receivers to measure the size and shape of each new forest fragment. In addition, note will be taken on land use around each fragment to aid in the estimation of the degree of connectivity of each fragment. Products: Ph.D. thesis, two publications, CD with spatial data of the study area for decision makers and NGOs interested in forest conservation. They are working on the regional level in three areas of cloud forest with 15 study sites all located in one of these. Analyses are planned at two spatial scales (i) The mountainous region (regional scale analysis of deforestation) and (ii) the landscape scale around study sites so it can relate with other aspects of project eg edge effects, and diversity impacts. Therefore, land use information is needed at two spatial scales. They need some maps at high resolution to link with other work packages. The maps already acquired of vegetation and land use came from governmental organisations such as CONABIO, INEGI, etc. were classified previously by other groups of investigators and include: 1980, 1996 1: 1,000,000 1984, 2000 1: 250,000 One problem is reconciling different classification systems used on different maps. IE does not have the capacity to analyse / process satellite images that may have to be acquired for comparisons between regions of the project. This includes LANDSAT or MMS impages from 1975, 1985 & 2000. In a previous meeting in Xalapa it was agreed that work on defining changes in patterns of land use should span 30 years, that classifications should be reduced and integrated between Chiapas, Chile and Mexico, that questions and data developed should be appropriate for each question, and that each of regions will have a representative for the purpose of communication between partners regarding this work package. *** Please refer to the report of the meeting held January 2002 in Mexico for more details; there will be a subgroup of specialists who will liaise on the remote sensing analysis – Jose Maria Benayas, Robert Manson, Susana Ochoa, and Cristian Echeverria 4) University of Acalá (Contact: Dr. José Maria Rey Benayas) Estos objetivos están coordinados por la Universidad Austral de Chile. Se ha establecido una interacción entre la UACH, el WCMC y la UAL por medio del doctorando Cristian Echeverría para el estudio en las áreas de Chile, y entre Robert Manson de Xalapa, Susana Ochoa de SOG-ECOSUR y la UAL para el estudio de las áreas en México. Los profesores de la UAL encargados de estas investigaciones son José María Rey Benayas y Javier Salas. El objetivo principal es calcular las tasas de deforestación, los procesos implicados y los patrones obtenidos. Estamos analizando en las 4 regiones de estudio tres horizontes temporales: ca. 1975 con imágenes MSS, ca. 1985 con imágenes TM y ca. 2000 con imágenes ETM+. Los análisis de imágenes serán completados con mapas de cobertura vegetal y distintas características físicas y de geografía humana del territorio. Ya se ha comenzado a analizar las 2 regiones de Chile gracias a la visita de Cristian Echeverría a la UAL durante el mes de septiembre. En Chile se persigue una clasificación última que distinga bosque nativo (primario y secundario), plantaciones (adulta, joven y recién cosechada), y áreas no forestadas (tierras agrícolas, etc.). En Xalapa y Altos de Chiapas se distinguirán, a priori, la siguiente clasificación simplificadas: bosques no perturbados, bosques perturbados (plantaciones, fincas de café o bosque secundario), pastos inducidos o naturales, cultivos (incluyendo milpas, caña de azácar, etc.), zonas antropogénicas (zonas urbanas, caminos, etc.), otros usos de suelo. Productos: mapas de usos del territorio, mapas de deforestación, 2 publicaciones y 1 tesis doctoral. Have assisted with classification of images in Chile. Offered help for Mexican groups. Using ThematicMapper for map classifications. 5) Instituto Politécnico Nacional (Contact: Dr. Rafael F. del Castillo) This partner is not involved officially in this work program but they have an interest in assessing the dynamics of land cover change for assessing impacts on population viability. They have air photos of their study area as well as a satellite image for 2000, but image is very coarse. They are also looking at what INEGI can supply. In conclusion, they are searching for information on pattern of land cover change but not planning a detailed assessment of deforestation. They are interested in linking with other partners regarding how apply remote sensing tools to address this question. CIIDIR does not have much capacity for remote sensing analysis but has some capacity in GIS. 6) UFZ Center for Environmental Research (Contact: Dr. A. Huth) This partner is not officially involved in this work program but is providing some support to UACH (Cristian Echeverría) with predictive land use modelling. 7) UNEP World Conservation Monitoring Centre (Contact: Dr. Lera Miles) This partner is providing support to C. Echeverría and access to images for the analysis of deforestation and fragmentation in Chile. 8) Universidad de Chile (Contact: Dr. Juan Armesto) This partner’s needs are being addressed by partners at UACH. KEY QUESTIONS / ISSUES TO ADDRESS (Elaborated during the December 2002 meeting in Oaxaca) 1. The standardisation of methods (e.g. modelling of deforestation & fragmentation) There are two main phases of this research 1) the need to document patterns of deforestation that have already occurred in the region (this will relate to the classification scheme), and 2) the need to develop models for predictive analysis of future landscape change. Various groups are working on such models, using a variety of statistical approaches, including ECOSUR, IE, UACH, UAL, WCMC. All agreed that the methods for mapping deforestation and modelling future changes needs to be discussed further. During the next meeting we should hold a series of working groups or mini-workshops focused on these and other technical issues related to Work Program 1. In the first year of the project we should focus our efforts on calculating deforestation rates and wait on the modelling of future changes in forest cover until the second and third years. 2. How do we describe patterns of forest fragmentation? This is a very important issue for other work packages, which will use this information. In order to make comparisons between regions, there is a need to standardise the methods of measuring / describing fragmentation. ECOSUR partners have used the FRAGSTATS package to this end and suggest that all partners might consider a similar approach to standardise results. However, there are many new packages that could also be used. These programs provide indices of matrix and edge quality and quantity, as well as the degree of isolation of fragments. There are three main things to measure – the size, shape, connectivity of fragments. The FRAGSTATS program can provide this information but is not very flexible. We need to research what other options / programs are available. The WCMC has developed an approach for a combined index that could also be applied. A suggestion was made that fragmentation should be analysed in the context of other variables (eg roads). All partners agreed to discuss subsequently which software should be used via email interchanges. The main task for all groups is to research the potential methods available for measuring fragmentation, and then discuss the advantages / disadvantages of each to come to an agreement on the best methods that everyone should use. 3. How classify images? How verify / ground-truth? Duncan suggested that all partners use NDVI as a way to standardise the classification scheme for creating land use maps from satellite imagery. This technique is easy to use and will insure that all maps are created in the same way; however, one potential problem is that an unsupervised classification may generate many errors. Another issue is that IE will be using maps that have already been classified and therefore, they will have to explore the classification methods used by the groups that created these maps to insure that they are compatible with the other regions of the study. The UACH will use the supervised classification to generate the land-use maps for each period. The most important issue is to compare images that are already classified. Through email partners will compare the classification schemes that all partners have and explore whether they can develop a common classification scheme. Initially there should be six classes of land use: The UACH suggests the following basic classes: grassland, shrubland, native forest, urban areas, bare grounds, other land-use. Depending on each study areas some classes may be sub-classified. “Other land-use” category may include particular land-uses (e.g. snow, commercial plantations, old –fields, etc.) that are not present in the other study areas. . When possible it’s advisable to compare with aerial photos as a double-check of the classification scheme developed. These six classes will be used to make initial comparisons between regions. A finer level of classification (different types of forest) will allow calculations of the loss of different types of native forests but this depends on the needs of each partner and region. 4. Which sort of images to use – standardise, or use a variety of image types? Regions should be comparable if IE can obtain images from 1975 (MSS) and 2000 (LANDSAT). Three periods over thirty years (1970s, 1980s and 1990s). LANDSAT ETM+ and TM have a pixel size of 28.5 square meters, which should provide the level of resolution needed for other work packages. 5. Obtaining images? The UNEP-WCMC has offered to help IE acquire MSS and LANDSAT images but needs details of which scenes needed & dates. Only IE needs images; all other partners now have them. 6. Need to undertake analyses at two spatial scales – There is some concern about the need for high resolution images / maps to provide information relevant to the other work packages of the project. What is the scale at which the different participants are working? The conclusion of partners was that the images from LANDSAT 1985, 2000 (pixel size 28.5 m resolution per pixel. So this should be sufficient? May need a digital elevation model to include in analyses. 7. Do we need to undertake analyses at same locations as locations of work on other work programs? In Chile and Xalapa this is the objective. However, in Chiapas the focus of fieldwork will be Los Altos where landscape-scale information is lacking. Land use maps will be needed undertake deforestation assessments in this area also. There was general agreement that 15 should be the minimum number of fragments to study for WP2. 8. What do we need from this work packages for the other work packages? There will be a need to scale up to link the different analyses. It remains to be seen if there are limitations in resolution of remote sensing data. a.