Cooperative Institute for Research in Environmental Sciences

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Rozita Abdul-Williams

Contact Information

Associate Scientist I
Office: Ekeley, Rm S250c
Tel: 303-735-0288
Email: rozita@cires.colorado.edu

Research Activities

1. Land Use Cover Change in Baram Watershed
2. Ecological Vulnerability Model
3. World Deltas Network

Other Affliations

PhD Student at Michigan State University (2002-Present)
Research Assistant at CGCEO (2002-2003)

1. An Analysis of Land Use Cover Change in the Baram Watershed Using an Integration of GIS/Remote Sensing and Human Environment Interaction

My research topic is firmly rooted in Land Use/Land Cover Change analysis with remote sensing and GIS applications. Potentially it offers an explanation of these land use changes through geospatial analysis and political ecology. It will be interesting to make a contribution that helps move political ecology forward as it continues to embrace geospatial technology in its various methodologies.

My study area will be in the Baram watershed of Sarawak, Borneo Island. Much of my concentration will focus on issues related to land degradation. Land degradation is a serious problem that has affected the historical pattern use of resources by the indigenous community in Sarawak. In view of the rapid logging and land development in Sarawak, the concern really is how to strike a balance. Water supply will become an increasingly difficult and expensive problem to tackle. A good theme for this study may include how the various impacts have been and will be affecting society and biodiversity when insufficient attention is given to the protection of catchments. Monitoring impact of activities such as logging and oil palm plantation usage on water quality (affected by silting and chemical discharge) will be important to enable appropriate mitigating measures to be developed.

Tackling this problem requires political will and awareness. Studies show that the Baram delta and river system indicates high suspended sediment loads caused by logging activities upstream. This contributes to rather serious problems in terms of soil erosion, loss of soil fertility, clogging of rivers and drainage systems and extensive flooding. Some of land use changes such as deforestation and land losses that have taken place have a big impact on human society.

The adverse form of land degradation occurring in the Baram watershed includes deforestation, soil erosion, pollution and the destruction caused by logging activities. These occurrences are crucial to understanding why the rainforest is degraded and destroyed in sight, which has affected the Penan’s ecosystem. When the forestland is disturbed or degraded, the ecology is damaged and the natural course of indigenous culture is at risk.

The environmental impact in the Baram Watershed of Sarawak, by soil erosion and other forms of land degradation, is overly familiar. This can be witnessed through the advancement of remote sensing and Geographical Information System (GIS) technologies. Land degradation is a serious problem that has affected the historical pattern use of resource by the indigenous group in Sarawak. This study will focus on the political ecology (state of affairs) of the Penan settlements in the Baram watershed, Borneo Island.

2. Ecological Vulnerability Model - Methods: Ecological Niche Model

[July, 01 – September, 01, 2005]

1. Apply standard GIS overlay and classification techniques to produce an initial set of coarse delineations of potential areas of vulnerability based on:
1. Physical criteria thought to define their terrestrial and marine extent, using highest resolution elevation.
2. Bathymetry data available among the PRIDE partners.
2. After validation of the criteria, the delineation will be duplicated using the niche-model technique and confirmed to produce the same results.
1. The model parameters will then be altered as needed to incorporate ecological criteria. This allows the model to be confirmed in its most testable mode, and then extended to estimate biotic distribution potentials for which less validation data are available.
2. The model produces a single algebraic equation for the delineation, where each variable is supplied by a data layer we have identified (or prepared) in the database as one of the critical delineation factors.
3. The model will give a spatial estimate of other similar units in the study region (where the necessary data exist to run the model).
3. These results will be validated as feasible, using Landsat or other classifications of known locations.
1. This provides a generalized boundary for each distributed site which can be used to window data from other sources.
2. This will facilitate compilation of integrated research databases across the sites for more detailed study of the ecology and vulnerability of affected communities.
4. Vulnerability maps can be produced using scenarios of sea level rise, if such model-produced scenarios are available from the other PRIDE partners.
1. The resulting set of boundaries will be stored as vector or “shape” files for distribution through existing PRIDE and NBII portals.
2. Thus facilitating other data compilations as needed.

Hawaii Project Outline:

1. Study of actual occurrence of algae invasion. What are the correlation and the variable of distribution?
2. Scale factors; what is the variable/factors that the invasion algae responses to? Temperature? Rainfall? Things that are responding to this ecology.
3. These factors are important to establish these algorithms. i.e. biological factors are an important time element.

Steps taken in the procedures:

Step 1: Parameterized the responds functions.
Step 2: Combining the axes.
Step 3: Preparing the database.
Step 4: Mapping the distribution.

Step 4: Mapping the distribution

1. Creating raster images (x) bathy.rst and (y) elevation.rst and convert to *.tif files. This is done in IDRISI using the "Export" command.
2. Import the parameters x = Bathy and y = elevation images in Mathcad 12 - Image processing extension pack. i.e.

x Ξ READRGB ("baram_bathy_modeltest+10000.tif"    ) – 1000

y Ξ READRGB ("baram_elevation_modeltest_rcl+10000.tif"    ) – 10000

3. Run the model in Mathcad 12 to produce an output of “Suitability” in matrices. i.e.



4. Export the matrix output to Tab delimitated text file format (*.dat). The output matrix can be display in "graph".
5. The *.dat can be exported back to IDRISI in SSTIDRISI (AsciiGrid/Spreadsheet) to raster file and display the final map suitability.

3. Delta Project - WDN Work Procedure

My work involves in producing the Delta’s general Area of Influence (AOI), and the Delta Area (DA) boundary files for each study areas. The boundary files were derived from masking and buffering the 1km DEM and 4km Bathy, which were used to define the initial thresholds. I am also responsible to produce a shape file and Arcinfo format of the boundary files. These are vector GIS boundary files for deltas in the World Deltas Database, which define the "Area of Interest" (AOI) for the purposes of the WDN. These boundaries are intended to be the standard area used to subset spatial data to add to the WDN and WDD. They are in easy-to-use formats (Idrisi/Vector and ESRI/Shapefile). There is also a .jpg image showing the boundary on a relied image for reference.

The delineation criteria were generated to the closest data-driven boundary meant to outline the area of influence, the other the active physical delta itself. The work procedure involved includes:

1. to define the large AOI, out to the shelf-break or equivalent
2. to define the delta proper by stepping up the bathy contour by distinguishing the bathymetry images.
3. to retain the elevation and of the alluvial valley in showing its presence in of same inland boundary.

This work will incorporate processing the Landsat imagery for 1990 and 2000 and applying a standard atmospheric correction. This includes identifying and mosacking necessary scenes that cover AOI and DA boundaries.

The Delta project will contribute to the development of a worldwide Delta database, part of the climate and global change research initiative. This database will provide access to wide arrays of information and data from field studies and satellite imagery, with GIS overlays on the deltas in question. It is significant to study the land loss of the Delta as it exists to sustain often large human populations. River Deltas of the world are renowned as fertile regions for agriculture. Deltas are key components of the hydrological system linking white and blue water. They are highly dynamic indicators and integrators of larger system processes, and hence they can provide valuable information that may be used for assessment and prediction of watershed and coastal change. This will be a useful study to initiate the potential scale of the problem, and to study the impacts of both climate and atmospheric compositional change on ecosystem functionality and the implications for the earth system.