Land use and Cover Change Dection by Modern Intersrated Technology GIS and RS

Abstract

The objective of this study is to investigate the spatial-temporal land use/land cover (LULC) changes of Shomadi area at Renk County in Upper Nile State - Sudan. 11 The huge potentiality and the rich vegetation cover of Shomadi area is seriously deteriorated due to increasing irrational anthropogenic activities. All attempts to manage these resources in sustainable manner failed due to limitation of information. Therefore it became necessary to carry out this study with the objective to produce thematic maps for the period 1973-2010 which can facilitate capabilities of planning, monitoring and management of these resources. To achieve this objective, field work is carried out. This includes geospatial technology (Remote sensing, GPS and GIS), where Landsat images (MSS, TM) and SPOT-5 of November 1973, November, 1987 and November 2010 respectively are used. Images pre-processing and classification are performed adopting object oriented (O.O) segmentation technique. As a result, seven classes level-1 are obtained. Along with this, soil samples are taken. They are analyzed in the laboratory to investigate the NPK, soil pH and Electrical conductivity. Then accuracy assessment is carried out. An overall accuracy (OA) of 94.09% and kappa accuracy of 91.26% are obtained. Nevertheless, vegetation attributes are also studied by Muller method, the so called “Point Centered Quarter method (P C Q)”. Moreover, secondary data are collected; observations are listed, personal interviews and questionnaire are also conducted. The field data are analyzed by SPSS, GIS and PC. However, the results of ERDAS imagine version and statistical analysis showed a remarkable decrease in forest lands from 48% to 25%, water bodies from 0.9 % to 0.5%, swamp area from 1.4% to 1.3% during 1973-2010. While data of the mechanized rain-fed farming reflected continuous gain from 16% in 1973 to 29% in 2010. However, similar trend of change showed by rangeland which was 33% of the total area in 1973 and it became 43.1% in 2010. The irrigated agriculture was 1% of the total area in 1973, but increased in 2010 to become 1.6% of the total area. 12 The settlement area was not shown in 1973 because of application of Low and Medium Resolutions (MSS and TM), but it is shown up when high resolution (SPOT-5) is applied in 2010 to represent about 0.03% of the total area. The frequency distribution of the dominant species showed great variability depending on soil type, pattern of rainfall distribution and severity of human activity. The tree density ranges between 28-1639 trees/ ha. where Acacia mellifera reflected the highest frequency distribution (96%), followed by Cadaba rotundifolia (59%) and Acacia nubica (44%), meanwhile the Albizzia sericocephala showed the lowest value of frequency (1%). In conclusion, irrational land use/land cover resulted in decrease of vegetation lands, losses of wildlife and habitats, negative impact on hydrological cycle, socio-economic and environmental settings. The study recommends the introduction of new farming system of profound produce and compatible with environmental settings and sustainable to development projects. Afforestation of the mechanized rain-fed areas with suitable A. species. Further study is needed to quantify reported water regime change, vegetation and games endangered and extinction species and the underlying factors responsible using high resolution satellite images. Introduction of new rules and ordinances that regulate vegetation and land use utilization. Also; the local communities should be participation in formulating and implementing these rules and ordinances should be encouraged.