Use of GIS, GPS and RS for Fertilizer Recommendations

After reading this article you will learn about the use of GIS, GPS and RS for fertilizer recommendation.

Precision agriculture provides better management of natural resources that leads to higher potential of increasing yields and economic returns in agricultural production. In this system, the agricultural management is tailored to the variability of conditions found in each field. Since fertilizer application is an important operation, it has to be carried out efficiently and judiciously to ensure optimum returns from its investment.

Precision Agriculture practices are aimed to optimize the use of soil resources to compensate the GIS-GPS-RS technologies are used in combination for precision farming and site-specific crop management. Precision farming techniques are employed to increase yield, reduce production costs, and minimize negative impacts to the environment. Using GIS analytical capabilities, variable parameters that can affect agricultural production can be evaluated.

These parameters include yield variability, physical parameters of the field, soil chemical and physical properties, crop variability (e.g. density, height, nutrient stress, water stress, chlorophyll content), anomalous factors (e.g. weed, insect, and disease infestation, wind damage), and variations in management practices (e.g. tillage practices, crop seeding rate, fertilizer and pesticide application, irrigation patterns and frequency).

Objectives of GIS, GPS and RS:

i. To create fertilizer variable rates map from oil palm yield data and foliar analysis;

ii. To use decision support system to create information from the foliar analysis to develop the foliar nutrient maps;

iii. To estimate the site-specific fertilizer rate requirements; and

iv. To maximize oil palm production through yield increase and efficient use of fertilizer inputs.

Benefits of GIS, GPS and RS:

The fertilizer variable rates map created will optimize oil palm production and save the environment through efficient fertilizer utilization. By developing the GIS database of the area, the plantation information can be efficiently utilized for management, forecasting and planning.

Precision Agriculture (PA) is an improved farming system where technologies such as Geographic Information System (GIS), Global Positioning System (GPS), and Remote Sensing (RS) are used to improve agricultural practices. The information and fertilizer rates map created will guide the actual application of fertilizer in the field in such a way that will optimize fertilizer usage and maximize yield production.

Geographic Information Systems of GIS, GPS and RS:

GIS applications enable the storage, management, and analysis of large quantities of spatially distributed data. These data are associated with their respective geographic features. For example, water quality data would be associated with a sampling site, represented by a point. A GIS can manage different data types occupying the same geographic space.

For example, a biological control agent and its prey may be distributed in different abundances across a variety of plant types in an experimental plot. Although predator, prey, and plants occupy the same geographic region, they can be mapped as distinct and separate features.

The ability to depict different, spatially coincident features. The ability to depict different, spatially coincident features is not unique to a GIS, as various computer aided drafting (CAD) applications can achieve the same result.

The Global Positioning System of GIS, GPS and RS:

GPS technology has provided an indispensable tool for management of agricultural and natural resources. GPS is a satellite-and ground-based radio navigation and locational system that enable the user to determine very accurate locations on the surface of the earth.

Although GPS is a complex and sophisticated technology, user interfaces have evolved to become very accessible to the non-technical user. Simple and inexpensive GPS units are available with accuracies of 10 to 20 mete, and more sophisticated precision agriculture systems can obtain centimeter level accuracies.

Remote Sensing of GIS, GPS and RS:

Remote sensing technologies are used to gather information about the surface of the earth from a distant platform, usually a satellite or airborne sensor. Most remotely sensed data used for mapping and spatial analysis is collected as reflected electro­magnetic radiation, which is processed into a digital image that can be overlaid with other spatial data.

Reflected radiation in the infrared part of the electro-magnetic spectrum, which is invisible to the human eye, is of particular importance for vegetation studies. For example, chlorophyll strongly absorbs blue (0.48 mm) and red (0.68 mm) wavelength radiation and reflects near-infrared radiation (0.75-1.35 mm).

Leaf vacuole water absorbs radiation in the infrared region from 1.35-2.5 mm (Samson, 2000). The spectral properties of vegetation in different parts of the spectrum can be interpreted to reveal information about the health and status of crops, rangelands, forests and other types of vegetation.

Applications of GIS, GPS and RS:

The uses of GIS, GPS, and RS technologies, either individually or in combination, span a broad range of applications and degrees of complexity. Simple applications might involve determining the location of sampling sites, plotting maps for use in the field, or examining the distribution of soil types in relation to yields and productivity.

More complex applications take advantage of the analytical capabilities of GIS and RS software. These might include vegetation classification for predicting crop yield or environmental impacts, modeling of surface water drainage patterns, or tracking animal migration patterns.