Application of GIS techniques in mapping related land use practices in flood plain wetlands. Upper Noun Valley drainage basin-Cameroon

The focus of this study is the application of remote sensing and GIS techniques to mapping of different land use practices both within and without the wetland area in the Upper Noun Valley drainage basin. The flood plain is rich in wetland products and fertile volcanic and alluvial soils. This potential makes the plain one of the major seasonal in-migration zone for agro pastoral activities during the rainy and dry season in the grass fields of Cameroon. Products associated to this wetland area, are fish, wood, fodder, herbs, reservoir and wildlife. These products trigger a number of diverse, related land use practices at all seasons of the year, including fishing, agriculture, transhumance, swamp rice cultivation etc. The plain alone is the home of thirteen different ethnic groupings that depends directly on the wetland products for their daily survival.  The close relationship of these land use practices both within the wetland area and the drainage basin, largely engender perturbations in the ecological processes and certainly creating an imbalance in the flood plain wetland ecosystem. The following annotated bibliography makes a review of wetland and GIS related studies that have been carried out around the world in order to guide this study

Joseph Spruce, Risa Wu, Russell Berry (2001). GIS Techniques for Evaluating Wetland Maps Derived from Remotely Sensed Data. International Journal of Remote Sensing, Vol. 22, No 1, Pp 89-98.

This paper discusses GIS techniques used in this study in Salisbury, Maryland. Using remotely sensed images from NASA’s Commercial Remote Sensing Program office, the aerial photographs were used for deriving wetland classification and mapping. The paper reiterated the fact that remotely sensed data products often constitute an invaluable component of GISs, and a great deal of software development has taken place to aid the use of remotely sensed data in GISs. Modern GISs give users the ability to conduct visual and quantitative analysis involving multiple kinds of digital spatial data, including remotely sensed imagery. In addition, GISs provide several tools for working with raster remotely sensed and thematic imagery. Several remotely sensed datasets were evaluated including: Airborne Terrestrial Applications Sensor (ATLAS) airborne daytime 2.5-meter multispectral imagery with bands in the visible, near-infrared, and thermal-infrared spectral regions; ATLAS nighttime 2.5-meter multiband thermal imagery; and AIRSAR airborne 9-meter multiband radar imagery. Additional datasets for mapping wetlands included a GPS-based survey of wetland boundaries, GPS-based locations of wells located across field-delineated wetness gradients, National Wetland Inventory digital maps produced at 1:24,000 scale by the U.S. Fish and Wildlife Service (USFWS), 1:24,000 U.S. Geological Survey topographic maps, and 1:8,000 color infrared (CIR) aerial photography acquired in 1995 during the same mission as the airborne daytime multispectral imagery. The result showed a much stronger correlation occurs in non-transitional wetlands and uplands. This GIS-based interpretive analysis the study noted can also be quantified for each wetness map by applying buffering routines on the wetness map, rasterizing each buffered output, and then cross-tabulating the gridded buffer file against the well wetness data. Doing so would provide an estimate of the proximity of each well to the wetland boundary. This similar observation and interpretive analysis will be approach in the study to be carried in the Upper Noun Valley to map Land use practices base on remotely sensed data sets and using GIS techniques the boundaries will be delineated.

Xiaojun, Y. and Zhi, L. (2005). Using satellite imagery and GIS for land-use and land-cover change mapping in an estuarine watershed. International Journal of Remote Sensing, Vol. 26, No. 23, pp. 5275–5296 

Satellite images and GIS methods are very vital instruments for assessing land use and land cover changes and related human role to influence these changes. This method is going to be applied in Ndop flood plain in Cameroon with inspirations drawn from this study conducted in Pensacola estuarine drainage area to characterize land-use and land-cover changes. The Pensacola bay was targeted because it is one of few exemplary large river-driven estuarine systems across the northern Gulf of Mexico. The study had two major sections. The first part was dedicated to the development of an improved method for coastal land-use and land-cover mapping, which was built upon hierarchical classification and spatial reclassification. An image scene was separated into urban and rural regions early in the classification, with a ‘mask’ defined by road intersection density slices combined with road buffers. Each part was classified independently in its most effective context and, later, both were merged to form a complete map. In spatial reclassification, image interpretation procedures, auxiliary vector data and a variety of Geographical Information System (GIS) functions were synthesized to resolve spectral confusion and improve mapping accuracy. This method was used to map land use and land cover from Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM+) imagery for 1989, 1996 and 2002, respectively. The second part focused on the analysis of the spatio-temporal dynamics of estuarine land-use and land-cover changes by using post-classification comparison and GIS overlay techniques. The project has revealed that a substantial growth of low-density urban land occurred in the lower drainage basin in connection with population and housing growth, as well as a significant increase of mixed forest land in the upper watershed as a result of active logging and harvesting operations. These growths were achieved at the cost of evergreen forest and wetlands, thus compromising safeguards for water quality, biodiversity of aquatic systems, habitat structure and watershed health in the Pensacola estuarine drainage area. Satellite images from Landsat and other related sources from 1990 to present will be collected for the Ndop floodplain in order have a good assessment of related land use changes and implications on the wetlands.

Calzadilla P, Damen M.C, Geneletti D. and T.W. Hobma T. (2002). Monitoring a Recent Delta Formation in a Tropical Coast al Wetland Using Remote Sensing and GIS. Case Study: Guapo River Delta, Laguna de Tacarigua, Venezuela. Environmental, Development and Sustainability, Vol. 4, No. 2, Pp 201-219.

This study centered on studying the integrated use of remotely sensed data and GIS to monitor a rapid recent delta formation in the Tacarigua Lagoon, a mangrove coastal protected wetland in the north-central coast of Venezuela. A historical set of aerial photographs and a radar image, together with a GIS, were used to assess the growth of the delta from the beginning of its formation up to the present time. Aerospace data interpretation and a field survey were utilised to study the formation of the Guapo River delta within the Tacarigua Lagoon and to map the expansion that this depositional environment has undergone.
This study is important to the study that will be carried out in the Upper Noun Drainage Basin because the study will center on acquiring remotely sensed data and Geosciences techniques to map related land use implications on the wetland habitat.

Zacharias I, Dimitriou E, and Koussouris T. (2004). Quantifying land-use alterations and associated hydrologic impacts at a wetland area by using remote sensing and modeling techniques. Environmental Modeling and Assessment, Vol. 9 No.1, Pp 23-32.

This particular study makes an attempt to conduct an integrated survey to identify land use changes and related hydrological alterations in the semi-mountainous subcatchment of Trichonis lake basin, in Western Greece, within the last 40 years. A variety of hydrologic and ecological parameters were analyzed and their spatial and temporal alterations were correlated to the observed land use modifications in order to assess the impact of these modifications on the area’s hydroecologic conditions. The study revealed that Land use changes and associated hydrologic disturbances were mainly caused by human activities, a common reason for wetlands degradation worldwide. The study particularly utilized remotely sensed data, GIS techniques and hydrologic modeling to estimate land use alterations during a 40-years period as well as associated changes in hydrologic parameters such as overland and underground flow, infiltration, evapotranspiration and water storages on ground surface.  The study however was limited to quantification of the land use impacts.  The following study will also assess the state of land use practices in a wetland area through GIScience in order to model the relationship between the land use and the wetlands in a drainage basin.

Gesche K, Michael B, Stefan W and Gerald B (2004). Mapping Land-Cover and Mangrove Structures with Remote Sensing Techniques: A Contribution to a Synoptic GIS in Support of Coastal Management in North Brazil. Environmental Management, Vol. 34, No 3 pp. 429-440.

The major objective of the study was to use a vector-based GIS to establish a platform for the integration of data gathered in the participating scientific fields and to provide basic modules for applications in biological, socioeconomic, and dynamic ecological modeling. The study combined satellite imagery, aerial photography, and field data, and this gave a standardized geomatching of an adaptive information system, in which ecological and socioeconomic parameters could be integrated. Land use classification was made possible with the master satellite image. However, due to the patchy, small-scale units of agricultural land use in the study area, the results of this classification were prone to inaccuracies, because the pixel size of Landsat data with 30m is sometimes in comparable order of magnitude as the small-scale land-use plots. The study concludes that the findings are a demonstration that mangrove ecosystems require several spatial and temporal levels of observation and interdisciplinary monitoring. This can be with tools such as a synoptic GIS, including remotely sensed data, useful to illuminate the important ecological and socio-economic components of a system and their relatedness. The following research to be carried out in the Ndop flood plain will seek to use several tools to collect GIScience data in order to establish a proper relation between the land use practices and the wetlands.

Sajeey R, Subramanian V. (2006). Land use/land cover changes in Ashtamudi wetland region of Kerala - A study using remote sensing and GIS. Journal of the Geological Society of India.  Vol. 61, No. 5, Pp.  573-580.

 This study is carried out in India in a stressed wetland area due excessive human intervention. The study assesses the land use/ land cover conversions in Ashtamudi wetland region from 1967 to 1997. The impact of land use/land cover conversion was quantified using the technique of Remote Sensing and Geographic Information System (GIS). This was with the aid of India Survey topographic map, hard copies of IRS-1A LISS 11, and IRS-1C LISS III images to determine the changes that have taken place in the wetlands due to human activities. Ashtamudi estuary, the second largest wetland ecosystem of Kerala is the deepest among all the estuaries of Kerala. The results from study shows that increasing population density, change in family system, extensive coconut husk retting and deposition of husk waste along the margin of the estuary, solid waste deposition from factories, reclamation of the estuary by local population and low profit obtained from paddy cultivation are mainly responsible for the large-scale land use/ land cover conversions in the wetland region. A similar approach will be use in the Ndop plain to determine the relationship between the different land use practices and the wetland area.

Lyon G and MacCarthy J, (1995). Wetlands and environmental application of GIS. Pp 400. www.eebookstore.com/pd_wetlands_and.cfm

This is an outstanding book that focuses on current capabilities of spatial analysis and modeling using GIS and related technologies. The goal is to be innovative with the application of tools to provide database of information to support modeling of phenomena. GIS technologies facilitate the processing of spatially distributed variables represented at different scales or resolutions. Also the digital approach of storing and processing spatial or image data, visualization and analysis, virtual realities and simulation modeling are discussed at length in this book.

Philip R, Beeri O, and Dekevser (2005). Remote wetland assessment for Missouri Coteau prairie glacial basins. Wetlands, Vol. 25, No. 2, Pp. 335-349.

 This study was carried out to develop and evaluated a remote sensing model for detecting basin buffer disturbance in North Dakota's Prairie Pothole Region (PPR). This was integrating satellite technology with knowledge of structural factors fundamental to wetland quality i.e., land-use and natural vegetation buffers surrounding water bodies. Four Landsat ETM+ scenes (May 31, Jul 02, Aug 03, Aug 19, 2002) and one SPOT 5 (Spot Image, France) image (Aug 07, 2003) were successfully acquired for this project. Landsat imagery provided temporal data required for initial classification steps, with 15-m pixels for panchromatic and 30-m pixels for visible, near-infrared (Near-IR) and mid-infrared bands (Mid-IR). SPOT 5 data provided a smaller area of interest and the fine resolution (10-m visible and Near-IR; 20-m Mid-IR) necessary for delineation of the narrow plant community zones found within basins. The main goal for remote sensing was to build a classification model to map wetland buffer information for thousands of small, dynamic basins. This lead to land use classification for example Vegetation was classified using the decision tree method that first differentiated plant communities into three classes: 1) cropland, 2) natural vegetation, and 3) alfalfa, which represent the model foundation. The study to be carried out in Ndop flood plain will use different data remote sensing data to classify the different land use activities in the flood plain.

Chen X. (2002). Using remote sensing and GIS to analyze land cover change and its impacts on regional sustainable development. International Journal of Remote Sensing, Vol. 23, No. 1, Pp. 107-124

Geographic Information system is use in this study to analyze data from high spatial resolution satellite sensors derived from remotely sensed data. The study focuses on acquiring remotely sensed data whereby GIS techniques were applied spatial analysis of land cover dynamics. Land cover change derived from this multi-temporal satellite data was use for impact classification on land cover change in the west coastal zone of Korea. The paper concludes that the results from this study provided very useful information to local government in decision-making and policy planning. The satellite-derived data used in this study are Thematic Mapper (TM) data acquired by Landsat-5 on 14 May 1985, 20 May 1987, 26 April 1990 and 20 May 1993 in Ansan City, Korea.
The land use classification that will be applied in the Upper Noun Valley wetlands will be base on the rainy season and dry season land use practices from the remotely sensed data.

Kashaigili. J. Mbilinyi, B, Mccartney, M and. Mwanuzi, F (2006). Dynamics of Usangu plains wetlands: Use of remote sensing and GIS as management decision tools. Physics and Chemistry of the Earth. Vol. 31 (15-16), Pp. 967-975.

 This study is a profound example of how Remote sensing and GIS technologies have proved to be useful tools for assisting decision-makers to locate and quantify changes in land resources, and hence to identify appropriate solutions for sustainable management of wetlands. The paper outlines the procedures adopted for investigating the dynamics of wetlands on the Usangu Plains, and the links between factors causing change, by utilizing remote sensing and GIS. The Usangu Plains are located in the southwestern part of Tanzania. Landsat-MSS and Landsat-TM images from 1973, 1984 and 2000, were used to locate and quantify the changes.  Satellite images were geometrically rectified and registered to the UTM map coordinate system UTM zone 36 South, Spheroid Clarke 1880, Datum Arc 1960, based on a previous georeferenced Landsat TM image of 14th August 1994. An ERDAS image processing system was used for all image data processing. The unsupervised image classification was used for all images. Twenty classes were formulated and confirmed through the use of ground-truth data and colour-composite images. Misclassified classes were interpreted visually and the results combined to respective classes. The results from the study showed a close link between ecosystem change and the increased anthropogenic activities. The increase in anthropogenic activities reflects an increased population. This is reflected in the images result showing that vegetated swamp cover increased in area between 1973 and 1984, and decreased tremendously in 2000 due to population increase.

Alphan H and Yilmaz K. (2006). Monitoring Environmental Changes in the Mediterranean Coastal Landscape: The Case of Cukurova, Turkey. Environmental Management, Vol. 35, No. 5, Pp. 607-619.

Cukurova is one of the largest coastal plains in Turkey that provides space not only for agriculture, but industries, settlement, and transportation. It is an important coastal wetlands ecosystem that has been increasingly disturbed in recent years. The objective of the study was to represent a methodology that relies upon multitemporal remotely sensed satellite data and digital image interpretation techniques to monitor landscape-level environmental changes in this region of southeast Mediterranean coastal zone of Turkey. Three Landsat TM and ETM+ data sets acquired in 1984, 1993, and 2000, respectively, were used to determine Land Use/Land Cover changes between 1984 and 2000. Topographic maps and aerial photographs from 1992 were used as the source of reference information for the analysis of satellite images and verification of change detection. Eleven LULC classes prior to digital image interpretation and changes were detected with agriculture as the major land use in the study area. Both pre and post-classification approaches were used in order to provide a strong basis for landscape-level environmental monitoring. The authors further noted that this study is crucial for developing countries, because the use of remote sensing in LULC change studies have become widely recognized as an effective method of change analysis. This method of determining LULC changes through remote sensing images will be applied in the Ndop floodplain with the use of aerial and topographic maps to verify changes detected by the satellite images from 1990 to present.

Mensing D, Galatowitsch S, and Tester J. (1998). Anthropogenic effects on the biodiversity of riparian wetlands of a northern temperate landscape. Journal of Environmental Management, Vol. 53 No.4, Pp. 349-377.

This study was carried out in fifteen different riparian sites along fourteen low streams to represent land use gradient from least impacted, most base on preliminary assessments of channel condition, land use and accessibility. This covers portions of three major catchments: the Upper Mississippi River, Lake Superior and the Minnesota side of the St. Croix River.  Those wetlands considered most impacted by anthropogenic effects have both on-site degradation and landscape alteration while least disturbed wetlands have minimal site and landscape alteration. To evaluate the land use assessment and site disturbance, a GIS land use/land cover database was developed using ARC/INFO7.07 (ESRI, 1992) at a 100m minimum mapping resolution to characterize landscape condition.  Existing digital land use data (from late 1970s to 19902) were obtained from several state and county agencies (regional data) and from the US Environmental Protection Agency (EPA) (statewide data). In consistencies in available data required updating or subcategorisation to be conducted for certain coverages by using recent (1991 or 1994) aerial photography. As some land use data were recorded in the 1980s, 1992 agricultural census data were used to estimate the acreage of agricultural land use to Conservation Reserve Program (CRP) land.  Land use data were grouped into six general land use types: urban, cultivated, rangeland, forest, wetland and water. Permanent land use features were verified in the field, such as the type, number, size and impacts associated with roads, bridges, buildings, culverts, ditches, feedlots, disturbed areas, etc. the study concludes that of the organismal groups surveyed in this study, birds are the best indicators of landscape condition within the near vicinity of small stream riparian wetlands and fish community composition corresponds to broader landscape land use patterns. In contrast, vegetation, amphibian and invertebrate communities are weaker predictors of land use impacts. The following study in the Ndop flood plain will assess the different anthropogenic implications on the wetland area with the application of GIScience.

Nathan M, Jiaguo Q, Gary R, and Jan S (2006). Investigating impacts of land-use land cover change on wetlands in the Muskegon River Watershed, Michigan, USA. Wetlands, Vol. 26, No. 4, Dec. 2006, Pp. 1103-1113.

Land use and land cover changes can result in direct ecosystem loss, as well as fragmentation causing decreases in wetlands. This paper’s objective was to investigate wetland quality changes resulting from land-use land cover alterations at a watershed scale. Landscape pattern metrics were generated to examine changes in wetlands characteristics between 1978 and 2000 in the Muskegon River Watershed (MRW), Michigan, USA. The Michigan Resource Information System (MIRIS) land use/land cover database was the primary data used in this investigation. MIRIS was developed from color infrared aerial photos at 1:24,000 scale as part of the National Aerial Photography Program. MIRIS geospatial processing was consistent with Federal Geographic Data Committee guidelines (Michigan Land Cover/Use Classification System 2000). MIRIS data originally came in the Michigan GeoRef Coordinate System (oblique mercator, NAD83). The research investigating stressor-response relations between land use land cover change and wetland stress measures had mixed results. The transition matrix indicates that, according to the MIRIS data, little change occurred in the total areas of wetlands identified across the entire MRW. The study also found varied responses between agricultural land-use intensity and wetland stress indicators, namely nutrient levels; invertebrate richness, and vegetation density, land use-hydrology alterations have generally shown stronger results. The following research will apply GIS techniques in mapping related land use practices in wetland area in order to better investigate land use implications on wetlands in Upper Noun Valley Cameron.

Hudson P, Coldiditz R., Aguilar R, Miguel (2006). Spatial Relations between Floodplain Environments and Land Use-Land Cover of a Large Lowland Tropical River valley: Pánuco Basin, México. Environmental Management, Vol. 38 No. 3, Pp. 487-503.

This study combines remote sensing and geomorphology to examine spatial relations between floodplain environments and LULC in the lower Pánuco basin of humid tropical eastern Mexico. The paper point out that the advantages of using remote sensing to examine floodplain landscapes are that it enables large river valleys to be mapped and can be used by agencies for assessment, planning, and developing sound approaches to environmental management. The new data sources that were used are the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) sensor system. ASTER data are appropriate for detailed LULC and geomorphic studies due to high spatial resolution in the visible, near-infrared (15-m), and short-wave infrared (30-m) portions of the electromagnetic spectrum. This study is particularly outstanding in this review because it has investigated the influence of individual floodplain environments on the pattern of LULC, associated with the topography in tropical environments. The paper further laid emphasis to the fact that, spatial differences in floodplain environments is of central importance to this study. And so, for this reason, the river valley was segmented where major changes in floodplain geomorphology occur. To segment the river valley, a longitudinal valley profile was created by sampling the floodplain elevation from the DEM at 5-km increments along the valley axis. The classification of the floodplain environments and spatial relations with LULC was made with satellite images acquired during the wet and dry season. Landsat 5TM image was utilized for wet conditions, whereas dry conditions were depicted with the ASTER mosaic. Relationships between LULC and floodplain environments were investigated using geographic information system (GIS) and standard cross-tabulation. Spatial relations between LULC and floodplain geomorphology showed a proxy for soils, hydrology, and topography, and so a deeper understanding of the floodplain landscape can be obtained by considering spatial relations between LULC and individual geomorphic units. The paper concludes by emphasizing that Land-use/land-cover classification is highly dependent on recent satellite imagery, but this does not preclude consideration of older historical and prehistoric influences. Thus by considering relationships between LULC and geomorphology, the results of this study have implications to improving floodplain management, particularly for flood hazards. Establishing this relationship is similar to the study that will be carried in the Upper Noun Valley in Cameroon whereby the related land use practices will be mapped in order to determine the close relations existing between the physical landscape, land use practices and the wetland area.

Haack, B. (1996). Monitoring Wetland Changes with Remote Sensing: An East African. Environmental Management, Vol. 20, No. 3, Pp. 411-419.

Environmental managers need current, accurate information upon which to base decisions. Viable information, especially in developing countries, is often unavailable. Satellite remote sensing is an appropriate and effective data source for mapping the surface of the earth, including a variety of environmental features. Remote-sensing-derived information is enhanced by being one component within a geographic information system (GIS). These techniques were employed to study an expanding delta in East Africa. The Omo River flows from the Ethiopian Highlands into the northern end of Lake Turkana, creating a large delta extending between Ethiopia and Kenya. This isolated and unique wetland feature has expanded by over 500 sq km in the last 15 years as measured by space-borne remote sensing techniques and corroborated by low-altitude aircraft reconnaissance flights. The growth of the delta appears to be a function of both increased sedimentation and decreased lake levels and river flows. Within the delta there has been a selective decline in wildlife and an increase in human activity, both pastoral and agricultural. The uniqueness of this isolated delta suggests that consideration be given to its possible protection and management.