Application of Vegetation Analysis and GIS

ASCOT Research International Journal, Volume 3, December 2010

Vegetation Analysis and GIS: Its Application to Sustainable Forest Management and Biodiversity Conservation RB J. Gallego

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Director, Department of Forestry and Environmental Sciences Aurora State College of Technology, Baler, Aurora, Philippines e-mail:[email protected]

ABSTRACT Resource databases compiled in the system are very crucial to meet the requirements of sustainable forest management. The compilation, analysis, and evaluation of these databases, established as resource information system, can define the management interventions appropriate for a specific area. The study was conducted based on the above mentioned principles as part of the MSc. study. Databases were created from the results of data sourcing and inventory. in terms of species composition. The floristic analysis showed that species of Dipterocarpaceae still dominates in the area despite of being intensively logged few years ago. The potential regeneration of the area is now getting better since the vicinity has plenty of saplings and seedlings of valuable species. Vegetation analysis, by principal components, was conducted to show relative correlation between species composition and environment variations like elevation, slope and soil types. The results showed no correlation at all. Considering faunal assessment and analysis, Philippine endemic and endengered species which needed conservation and protection were found in the area. Along with these ample data gathered stored in the system, simple GIS analysis where generated to identify areas with important biodiversity. Added to this are the areas that needs enrichment planting and areas needed silvicultural treatments like liberation cuttings. INTRODUCTION The Philippines is included among the countries with lush tropical rain forests. Reference [1] reported that 50% of the country was covered with natural forest. The latest survey showed that the remaining forest cover dropped from 15 million in 1911 to only 6 million hectares. The Philippines now faces the dilemma of deforestation. Droughts, floods, altered climatic conditions, and soil erosion are

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just the few among such consequences. The aftermath of environmental destruction alarms everybody and the burden of concern rests on forest managers and environmentalists who work directly with forests. Forest resource management plays an important role in the conservation of the remaining natural forest resources that will play a critical role in attaining both economic and ecological goals. One prerequisite towards effective management of a forest is through gathering of ample and reliable information about the forest itself and compiling them in an orderly system for analysis and retrieval. Primary data about the forest usually comes from forest inventories. Forest inventory is the primary approach in dealing with forest resource management because it shows record of location, extent, nature, condition, and productive capacity of a nation’s forest. Today, invent ory and planning of forests involves the use of aerial photographs. Aerial photography is widely used as a component of a more complex inventory design. If sampling techniques t echniques have to be carried out by field measurements, aerial photos are the best tools for stratification [2]. Furthermore, Geographic Information System (GIS) solves complexities in managing inventory and remote sensing data. GIS technology has the capability for storing, exploring and querying data. Geographic Information System (GIS) is an effective management tool that serves as clearinghouse for all relative information about any forest area. It plays important roles in defining management interventions appropriate for the area of interest. Integrated in the feedback loop system of managing resources, GIS enables the manager sees whether or not the management of the area of interest is in accordance with sustainable forest management criteria and indicators. RIS gives the manager the cues where and when to make adjustments to current interventions so that the sustainable forest management stays on course. At present, most of the forest management interventions are implemented directly to areas of interest without knowing the possible effects of the results. Although these interventions are based on applicable concepts, one should note that the applicability of some concepts varies from case to case depending on the actual situation of the area of interest. The health of our remaining forest resources should not be sacrificed to justify faulty management decisions. In this regard, the need to establish GIS coupled with some vegetative characterization techniques like vegetation analysis is essential in managing forest resources like that of ASCOT Reservation Area in Aurora Province. The current study was conducted in partial fulfillment of the requirements for a MSc. in Forestry [3].

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The Role of GIS Reference [4] and [5] identified the need for accurate, scale-controlled maps and attribute database derived from site-specific inventories. This could be possible through a computer system capable to store, retrieve, update inventories and create site-specific resource map. Furthermore, [6] cited some requirements for an effective resource management. He mentioned that resource inventory should be specific and the means of analyzing and managing information should be sophisticated enough to address environmental issues. A Geographic Information System (GIS) allows sophisticated handling and analyzing information. The user can use his creativity and knowledge in manipulating one or several parameters or in creating and testing models based on hypothesis. This will allow the user to see the outcome of forest operations before it is being applied in actual situation [7]. In addition, GIS and Remote Sensing (RS) have wide applications to assessment and allocation of resources, environmental monitoring, determination or prediction of vegetation or wildlife habitat, and for archaeological and harvest scheduling schedul ing purposes. The application is inventive because the user has the full control over the use of the th e system based on its personal preference, objectives, and the available resources. A GIS can also provide solutions to sophisticated problems in management like locating or geo-referencing, forest condition and trend assessment, pattern analysis and modeling [8]. METHODS 1. Vegetation Analysis Floristic composition can be analyzed by identifying the species and families of trees encountered within inventoried plots. Sorensen`s Similarity Index Formula [9] was a helpful tool in comparing plots pair-wise based on index of similarity. The index has the following formula: IS= (2C/A+B) x 100

Where: IS= Index of similarity C= No. of species common to two plots A= Total no. of species in plot A B= total no. of species in plot B

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RESULTS The study was initiated to provide maps, aerial photographs, reports and other related documents regarding the area of interest. It was followed by inventory preparation, aerial photo-interpretation, establishment of continuous forest inventory (CFI) plots, and data gathering on established establishe d CFI plots. 1. Inventory Results and Analysis After doing inventory, data were collated and analyzed to determine the resource composition of the area. This present study was identified 154 species belongs to 37 families. The study revealed that the area is dominated by the species belongs to the family Dipterocarpaceae. The presence of pioneer tree species in the area is due to the fact that the area is a logged over forest of which gaps were opened for their emergence. The average tree density of the area is 463 individuals per hectare. In terms of saplings, the area is dominantly covered by species belonging to family Dipterocarpaceae, Euphorbiaceae, Moraceae, Lauraceae, and Meliaceae. The average sapling density of the area is 3,157 stems per hectare. In contrast wildlings distribution of the area is minimal. Overcrowding by saplings could have possibly inhibited their presence. Whenever wildlings are present in any given subplot, they are mostly composed of lesser-used species. In terms of non-timber products, only palm species were roughly estimated. The results showed that there are 13 species of palm in the area with the average density of 3 individuals per square meter. Based on simple faunal inventory and analysis, the area holds six bat species, eleven birds, four frog species, and one small non-volant mammal. Among the captured fauna, mostly were identified as Philippine Endemic species, three bird species were identified as Near Threatened, and one bat species as Vulnerable or considered at a low level of endangerment. 2. Vegetation Analysis Vegetation analysis was conducted to provide information on the distribution of species as a function of the environmental factors. As to the results of the study, no distinct groupings of species in relation to the environmental gradients of elevation, slope, and soils was identified. The area is heterogeneous in nature and the results of the study might be attributed to the subjective sampling of CFI plots (Figure 1). 3. GIS Application on Resource Analysis Stand and stock analysis were used to demonstrate density and volume distributions for each species group. The results showed that the density and 4


volume of lesser-used species dominates the lower diameter classes. However, dipterocarp and other common hardwood (OCH) groups dominate the upper diameter classes. Regeneration and faunal analysis were conducted also to determine the distribution of regeneration and faunal components in the area respectively. After resource analysis, resources information was stored in a database. Appropriate GIS databasing procedures were followed to create a cell-based database [10] (Figure 2) that contains information on slope, soil type, total volume, total density, volume of species groups, volume per diameter classes and many more. Resource databases were subjected to surface analysis of the GIS and different resources were mapped geographically. This present study produced density, volume, sapling, and wildling distribution maps. Each map reveals the content of every point in the area whether in terms of number of individuals or in terms of volume. Figure 1. Vegetation analysis showing similariry index of plots along gradients of elevation (yellow, green and red corresponds to low, mid, and high elevations ele vations respectively).

4. Establishment of Protocols The study also includes the establishment of practical protocols to allow repeatability of results and improvement of accuracy. In this regard, protocols on stratified random sampling with the aid of aerial photograph are recommended. Additionally, protocols on vegetation analysis to relate vegetative data to environmental features of the area were also established to benefit entities that wish to duplicate the same endeavor.

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5. Use of GIS in Identification of Areas for Management and Conservation Furthermore, a given natural forest resource can be mapped showing its boundary including specific features that are of extreme interest in management and conservation. The GIS query, sort, and extract of data relevant for management and conservation produced the following: areas for enrichment planting, areas that need silvicultural treatments, and areas with biological importance. Finally, one of the aims of this study is to propose management schemes for the area that are in line with the criteria and indicators of sustainable forest management [11]. Management schemes proposed include aspects on legal and policy framework, sustainable and optimal production of forest products, environmental protection, plantation Figure 2. Cell-based resource database for management, and GIS/RIS framework. V. RECOMMENDATIONS Many automated technologies are recognized to make substantial improvements in the manner in which inventories are conducted and databases are created. For better study results the study, I recommend that one should search appropriate methods, procedures and even tools that could give substantial information regarding forest resources. During the actual conducting of the study, several problems surfaced especially in choosing appropriate methods of sampling and inventory designs that could give results with much higher accuracy. If one will replicate this kind of work in other areas, the following recommendations are to be considered. 1. Use of RIS is highly recommended in managing complex forest resources. 2. Use and monitoring of continuous forest inventory (CFI) plots is recommended especially when the purpose of management is to perpetuate optimum levels of resources over a long period of time. 3. Steps in creating resource databases should be followed and improved in future research projects that should be conducted. 6


4. Management schemes identified are recommended for implementation by ASCOT. This is to utilize the system and the databases to its full extent in maintaining forest forest productivity and sustainability. It should be mimicked in other areas also. 5. If not hindered by financial constraints, use detailed wildlife study instead of rapid biodiversity appraisal. This is to reflect other important species in the area that are not recorded due to incapability of the methods and the researcher. 6. Density and volume maps needs to be verified in the ground. Ground truthing will enhance the reliability of the study and will test the degree of accuracy of the RIS system in calculating densities and volumes at any point of the area given only the data from sample plots. REFERENCES

H. N. Whitford, The Forests of the Philippines, Vol. 1: Forest Types and Products. Bureau of Printing, Manila, 1911. H. Kenneweg, , H., Principles of Aerial Forest Inventory. In: “Application of Remote Sensing and Geographic Information Systems in Managing Tropical Rainforests and Conserving Natural Resources in the ASEAN Region. DSE/AIFM/FAO, Kuala Lumpur, Malaysia. Pp. 116 - 130. 1991. A. Lyyssonen, Assessment of Forest Resources for Management. In: Proceedings of the Eight World Forestry Congress, Diakarta, Rome: Food and Agriculture Organization of the United Nations, 1978. S. H. Smith, Information Needs for Activity Planning in Forestry . In-place inventories, principles and practices: Proceedings of the national workshop. Orono: University of Maine. 1981. K. C. Boling, D. Murphy, M. Goodwin and M. D. Sullivan, Landscape Modeling In IDAHO: Meeting The Challenge Through Organizational And Technological Innovation . Journal of Forestry, Vol. 94 No. 2. pp. 16 – 20. 1996.

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F. Croft and B. Kessler, Remote Sensing, Image Processing, and GIS: Trends and Forecast. Journal of Forestry Vol. 94, No. 6. 31-35 pp. 1996. I. Bayer, Introduction to GIS. In: Application of Remote Sensing and Geographic Information Systems in Managing Tropical Rainforests and Conserving Natural Resources in the ASEAN Region. DSE/AIFM/FAO, Kuala Lumpur, Malaysia. pp 220 252. 1991. D. Mueller-Dombois and H. Ellenberg, Aims and Methods of Vegetation Ecology. John Wiley and Sons, New York. 1974. N. C. Bantayan, GIS-Based Assessment Monitoring And Evaluation (GAME): An Unbiased And Transparent Approach To Sustainable Resource Development And Management. Unpublished Professorial Chair Lecture, , College of Forestry Forestr y and Natural Resources, University of the Philippines Los Baños. March 5, 2004. S. Higman, S. Bass, N. Judd, J. Mayers and R. Nussbaum, The Sustainable Forestry Handbook: A Practical Guide For Tropical Forests Managers On Implementing New Standards. Earthscan Publications Ltd, London. 1999.

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Application of Vegetation Analysis and GIS

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