Remote sensing: Remote sensing is the science of acquiring information about the earth’s surface without actually being in contact with it. This is done by sensing and recording reflected or emitted energy and processing, analyzing and applying that information.

Geographical Information System (GIS): GIS is a systematic integration of computer hardware, software, and spatial data, for capturing, storing, displaying, updating manipulating, and analyzing, in order to solve complex management problems.

Key components of GIS: The GIS constitutes of five key components, namely hardware, software, procedure, data, and users as shown in fig. These five components need to be in balance to function any information system satisfactorily.

 

Hardware, software and procedure for capture, storage, processing, analysis, display etc.

Data means Maps, aerial photographs, satellite images, statistic tables, etc.

Users for Design of standards, updating, analysis and implementation.

Applications of GIS in Agriculture

Geographic Information Systems are incredibly helpful in being able to map and project current and future fluctuations in precipitation, temperature, crop output, and more. By mapping geographic and geologic features of current (and potential) farmland scientists and farmers can work together to create more effective and efficient farming techniques; this could increase food production in parts of the world that are struggling to produce enough for the people around them. GIS can analyze soil data combined with historical farming practices to determine what are the best crops to plant, where they should go, and how to maintain soil nutrition levels to best benefit the plants.

Many organizations are now implementing GIS systems including the USDA. They use many GIS variations in each of the USDA sectors to best capture what that department specializes in; in recent months, however, the benefit of combining this information has been realized due to the incredible capacity of GIS to transform and combine large amounts of data into a data set. In the United States GIS systems are used by the USDA to protect crops, solve crop issues, and investigate fraudulent claims of crop damage as well as give farmers an easy way to access information about their crops season by season.

Agricultural Geographic Information Systems (AGIS) can map not only topography and crop health, but help solve wider economic issues in municipalities and urban centers that may stem from rural farming practices. Farmers in the States are able to access the GIS data on their lands; a program called CropScape and another called VegScape allows farmers to interact with the data without having a GIS themselves, ask questions and interact with the data as well as provide valuable on-ground data that can’t be gathered via satellite. Jeffrey Bailey, the chief of the National Agricultural Statistics Service’s Geospatial Information Branch, estimates the accuracy of their crop data is in the mid-90th percentile with the added ground data from farmers.

GIS applications

·         Crop health analysis

·         Precision agriculture

·         Compliance mapping

·         Yield estimation

Scope

• Crop average estimation
• Crop modeling for yield & production forecast / estimation
• Crop & Orchard monitoring

      Benefits

•         Timely availability of crop statistics for decision making & planning

•         Crop growth monitoring

•         Soil status monitoring

•         Regular reports regarding total area under cultivation

Applications of GIS in forestry:

Forestry involves the management of a broad range of natural resources within a forested area. In addition to timber, forests provide such resources as grazing land for animals, wildlife habitat, water resources and recreation areas. The U.S. Forest Service is responsible for the management of forest harvesting, grazing leases, recreational areas, wildlife habitat, mining activities as well as protecting endangered species. To balance the competing resource conservation and resource use, activities must be accommodated. Accessing the feasibility of these multiple uses is greatly enhanced by the use of GIS techniques.
For example, the GIS for Flathead National Forest in Montana includes digital terrain data, vegetation associations from Landsat satellite data, timber compartments, land types, precipitation, land ownership, administrative districts and the drainage network. The GIS has been utilized for such analyses as timber harvesting, habitat protection and planning the location of scenic roads.
Over the past eight years, GIS technology has been widely accepted by public as well as private forestry agencies. In large part this has been a result of the benefit of using GIS technology over current forest maps. The primary management tool for timber production in America is the forest inventory. It is used to access the existing forest resource and develop harvest schedules and treatment programs to project future timber supplies and for other operational planning activities. Forest inventory data is collected using remote sensing techniques.
The conventional forest inventory was done progressively with a small portion of the forest being inventoried each year. To update a forest cover map could take 20 years or more with expensive manual drafting. With GIS, the forest cover maps can be updated on a constant basis and it provides the forest managers more current data than what was previously available. With GIS technology, the average age of the information in the forest data base could be reduced from 20 years to only a few weeks. The time factor alone has led to a wide acceptance and large demand for GIS applications in forestry.
In itself, the use of GIS to update the forest inventory maps is not much more than automated cartography but it is the analytical power of GIS that sets it apart from cartography. The GIS can store and analyze the forest information in ways that could not be previously done. It can be used to calculate the harvestable timber in the forest or model the spread of a forest fire.

Scope

•         Satellite image based forest resource mapping and updation

•         Forest change detection

•         Forest resource inventory

•         GIS database development

Benefits

•         Availability of baseline  information

•         Planning for aforestation  strategies

•         Futuristic resource planning

•         Sustainability of environment

•         Wild life  conservation & development for recreation purpose

Land cover and Land use:

Land cover is the physical material at the surface of the earth. Land covers include grass, asphalt, trees, bare ground, water, etc.

"Land cover" is distinct from "land use", despite the two terms often being used interchangeably. Land use is a description of how people utilize the land and of socio-economic activity, Such as human activities using the land for industrial zones, residential zones, etc.

Land cover refers to features of land surface, which may be natural, semi-natural, managed, or manmade. They are directly observable by a remote sensor. Land use, on the other hand, refers to activities on land or classification of land according to how it is being used, such as residential, industrial, commercial, agricultural, recreational, etc.

Land use denotes the human employment of the land, so that a change in land-use at any location may involve a shift to a different type of use, for instance, from farming to residential, or a change in the intensity of use.

Generally, land-cover does not coincide with land-use. A land-use is composed of several land covers, for example, a residential land-use class not only contains built-up class but also contains vegetation class, water class, etc. Remote sensing data can provide land cover information rather than land-use information. The properties measured with remote sensing techniques relate to     land-cover, from which land-use can be inferred, particularly with ancillary data or already known knowledge. Identifying, delineating, and mapping land-cover is important for global monitoring studies, resource management, and planning activities.