Environmental Geographic Information System and Remote Sensing

  Attribute data refers to non-spatial information that provides details about a spatial feature. Spatial data includes both location information and additional attributes accompanied with it. There are two methods for linking the tables: joining and relating. Joining a table involves establishing a  temporary relationship between tables through a relational Data Based Management System (DBMS). The tables need to have a common field and the original stored data remains unaffected. Calculation views can apply a cardinality setting to joins which specifies the number of matching entries in the other tables for each entry in one table. Cardinality types include one-to-one, one-to-many, many-to-one and many-to-many. On the other hand, relating tables are similar to joins but the tables remain separate and selected items in one table may be highlighted in the table.  A query is used to extract specific records from a table based on specified conditions. Many databases utilize a specialized

  In GIS, there are two types of basic geoprocessing with raster data analysis: single layer analysis and multiple layer analysis. For the single layer analysis, reclassification or recoding is basically assigning a new range of values to all pixels in the dataset based on their original values. This simplification allows for fewer unique values and cheaper storage requirements. Buffering for raster data tends to approximations representing those cells that are within the specified distance range of the target. For the multiple layer analysis, the clipping process of raster data results in a single raster that is identical to the input raster but shares the extent of the polygon clip layer. The overlay process of raster data is that the number within the aligned cells of the input grids can undergo any user-specified mathematical transformation. The Boonlean raster overlay methods can use the connector (AND, OR and XOR) to combine the information of two overlying input raster data sets

Upon initial observation, Kampung X is currently facing a severe issue with erosion. As a researcher assigned by the Department of Agriculture Malaysia, my responsibility entails 1the task of conducting studies on the soil erosion rate from 1990 to 2010. The Revised Universal Soil Loss Equation (RUSLE) is used as it can estimate erosion and plan conservation measures by predicting the amount of soil loss in specific fields with specific slopes. This equation utilizes five key factors that can be assigned numerical values to predict the soil loss at a given location. The soil loss is calculated as follows: A = R × K × LS × C × P   where A is annual soil loss (tons/ha/yr),  R is the rainfall erosivity factor,  K is the soil erodibility factor,  LS is slope length and steepness factor,  C is cropping and management factor, and  P is conservation supporting practices factor (Yoder and Lown, 1995) Rainfall erosivity (R) factor is the index that measures the erosion force of specific rainfa

A geoprocessing tool is one that systematically manipulates either the geometry or the attribute information or both of a vector GIS data file. It is used to perform various spatial operations and analyses on vector data. These tools allow for tasks such as buffering, clipping, merging, intersecting, dissolving, and more. They provide the means to extract, transform, and analyze data within a geographic context, facilitating effective spatial analysis and decision-making processes.   The photo above clearly shows the function of the 6 basic toolkits. Basic six toolkits Buffer - creates a geometric area around vector features by using points, lines or polygons (input) at a specified distance of a feature or features (buffer width) - can create variable distance buffers based on attribute value  - use equidistant projection to center the point from that point, know the scale well and can draw buffer Clip   - subset tool - large dataset to clip down into smaller subset/dataset - clip oper