RANGE LAND MANAGEMENT IN ETHIOPIA

RANGE LAND MANAGEMENT IN ETHIOPIA

The future of range land resources development and management is dependent upon increased scientific capability. Remote sensing technology can contribute information for a variety of range land resource management applications. In future we can expect to see an increased number of professional range managers with expertise in remote sensing. This training will include, in addition to principles of aerial photo interpretation, digital image

Analysis technology, increased use of geographic information systems, airborne video remote sensing, and the use of newly developing high resolution systems. The data will be obtained from both aircraft and spacecraft. Applications will include inventory, evaluation, and monitoring of rangeland resources and the incorporation of remote sensing data to support and improve the decision processes on the use, development, and management of range lands. The art and science of range management is being pushed to new heights as practitioners and scientists approach the future. Changes in range management are inevitable. Expectations of high technology will be realized only when range professionals are able to apply new scientific developments to important rangeland resource management problems.

Remote sensing, the acquisition of information concerning an object or phenomenon without physical contact, is one such scientific discipline. Range land resource management will become strongly dependent upon increasingly sophisticated, holistic approaches.

Remote sensing, along with Geographic Information Systems (GIS), can provide a fresh approach to the use, development, and management of range lands throughout the world.

Remote sensing has been recommended for at least 30 years for assisting with rangeland resources development and management on a worldwide.

Due to the extensive nature of range lands and the recognized need to manage them at

Low cost, remote sensing is considered to have significant promise for the future.

The science is provided mostly engineers, physicists and computer specialists who have increased our abilities to exploit information inherent in various regions or wavebands of the electromagnetic spectrum. Range scientists contribute specialized knowledge and interpretation. The proper interpretation and application of remote sensing is an art. Inherent in this is the importance of developing an understanding of the ecology of the landscapes and of the vegetation-landform-soil relationships as a basis for image interpretation. Remote sensing interpreters can study certain features directly and other features only indirectly by inference or association. We are using the concept of surrogates wherein we identify and measure easily observed features that are related to more complex features or phenomena that a range scientist or manager wishes to identify, measure, and judge the significance of.

 For example,

It is possible to measure crown cover of shrubs on B large-scale vertical aerial photograph, but it is quite difficult, if not impossible, to accurately measure height or biomass. Research in remote sensing is required to establish useful and unique inferential relationships that are relevant to range management decision processes.

Steps in remote sensing

I define the problem and seek information.

II Determine the appropriate remote sensors.

III Acquire the remotely sensed data.

IV Correlate the data with ancillary ground data.

V Analyze the data for its information content.

VI Report and/or publish the information.

VII Interpret and use the information.

Range land Vegetation Mapping

Range managers are interested in the distribution and condition of the vegetation and forage base as it occurs in space and time. Areas of range land vegetation can be mapped from space or aircraft altitudes with reasonably high levels of accuracy using multi-spectral data and image processing systems. Photo interpreters with training in range management, plant ecology and soils, and with field experience in the area in question, can map the various plant communities or ecological sites. These interpreters, after gaining experience can effectively use vertical aerial photographs at various scales and stereo viewing to map homogeneous polygons bounded by ecotones that represent vegetation communities.

One can develop a map with good accuracy for a given area with remotely sensed data obtained at a particular time and date. lf, however, the data are projected in either space or time the classifications or mapping accuracy is significantly reduced.

Machine processing techniques to map and evaluate range vegetation communities begin with the creation of spectral class statistics of the pixels representing the area of interest

Three basic methods used to create spectral class statistics are supervised, unsupervised, and a mixed approach.

Geographic Information Systems

It is relatively new but is growing extremely rapidly. A GIS is an information technology system which stores, analyzes, and displays both spatial and non-spatial data. All features on a range landscape can be reduced to one of these categories. This technology has evolved as a result of the need to use mappable information to make decisions concerning preservation of land

resources based on a range of institutional, political, economic, and environmental data concerns. GIS are powerful tools for integrating and analyzing data derived from remotely sensed imagery

Interpretations, soil surveys, vegetation maps, land ownership maps, utilities maps, water resources, geology, mining, and many other potential themes that can be presented spatially. These geographically referenced data sets are spatially registered so that multiple themes of data can be quickly compared and analyzed