Annotated Bibliography of 

Remote Sensing Methods for 

Monitoring Desertification

GEOLOGICAL SURVEY CIRCULAR 851

Annotated Bibliography of 

Remote Sensing Methods for 

Monitoring Desertification

By A. S. Walker and Charles J. Robinove 

GEOLOGICAL SURVEY CIRCULAR 851

1981



Annotated Bibliography of Remote Sensing Methods 

for Monitoring Desertification

By A.S. Walker and Charles J. Robinove

ABSTRACT

Remote sensing techniques are valuable for locating, assessing, and monitoring desertification. Remotely sensed data provide a permanent record of the condition of the land in a format 

that allows changes in land features and condition to be measured. The annotated bibliography of 118 items discusses 

remote sensing methods that may be applied to desertification 

studies.

INTRODUCTION

The purpose of this report is to briefly evaluate 

the ways in which remote sensing can contribute 

to our knowledge of factors which cause or exacerbate desertification and to list sources of additional information. In addition to presenting a 

brief state-of-the-art look at the use of remote 

sensing in monitoring desertification, this review 

and annotated bibliography is intended to increase 

interest in and support for the use of techniques by 

remote sensing researchers and individuals with 

responsibilities for planning and decisionmaking 

in areas subject to desertification.

The bibliography is not an exhaustive one, 

although we have tried to make it representative. 

We wish to thank William Doyel and Patricia 

Paylore for reviewing this paper and suggesting 

several significant references.

DESERTIFICATION

Desertification, here considered as the decrease 

of productivity of arid and semiarid lands, has led 

to widespread starvation, severe decreases in food 

supplies, and disruption of land use patterns both 

along the perimeters of many of the world's natural deserts and far from these deserts. Although 

the phenomenon has been observed throughout 

human history, the term "desertification" has only 

been used in this decade. There is not, as yet, a

generally accepted rigorous definition of the term. 

The United Nations Plan of Action to Combat 

Desertification defines desertification as

"the diminution or destruction of the biological potential of the 

land, [which] can lead ultimately to desert-like conditions. It is 

an aspect of the widespread deterioration of ecosystems, and 

has diminished or destroyed the biological potential * * * for 

multiple use purposes at a time when increased productivity is 

needed to support growing populations in quest of development. * * * In general, the quest for even greater productivity has intensified exploitation and has carried disturbance 

by man into less productive and more fragile lands. Overexploitation gives rise to degradation of vegetation, soil, and 

water. * * * Desertification is a self-accelerating process, 

feeding on itself, and as it advances, rehabilitation costs rise 

exponentially" (Reining, 1978b, p. 3).

Desertification can have both natural and manmade components, which may reinforce each 

other. For example, the practice of intensive livestock grazing during a series of naturally dry 

years represents an extreme in the desertification 

process.

Desertification was first brought to world attention in the 1930's when parts of the Great Plains of 

the United States turned into the Dust Bowl as a 

result of poor farming practices initiated during a 

"wet" cycle. Millions were forced to abandon their 

farms and their livelihoods. By 1973, drought that 

started in 1968 in the Sahelian countries of Africa 

was responsible for the deaths of between 100,000 

and 250,000 individuals, the disruption of millions 

of other lives, and the collapse of the agricultural 

bases of five countries. Over $200 million in cash 

and food were donated by private individuals, governments, and the United Nations in an effort to 

prevent mass starvation. Reining (1978b) estimates that desertification currently affects more 

than 600 million people and one-third of the 

Earth's land surface.


combining the four Landsat bands. Visually, the 

resulting enhancement is equal to the more expensive computer enhancement; however, quantitative control of the process is lacking.

Standard and enhanced Landsat images can be 

used to inventory land use and monitor surficial 

changes in areas susceptible to or undergoing desertification. The images may be used to locate, assess, and monitor changes in vegetation, soil, 

water, and land use. El-Shazly and others (1977a, 

1977b, 1978) use transparencies of Landsat bands 5 

and 7 images to delineate water-bearing units and 

to map present and former drainage systems in 

arid lands in Egypt. They also compare sand-dune 

belts interpreted from Landsat images with those 

mapped by the survey of Egypt 45 years previously 

and find that the belts have moved a considerable 

distance. Hielkema (1977) studies temporal tonal 

variations on black-and-white Landsat multispectral scanner (MSS) images and correlates the variations with ground-collected data.

In addition to standard mapping techniques, 

Robinove (1979) has suggested a second method in 

which Landsat images may be used. He notes that 

terrain brightness, as measured by Landsat scanners, represents an integration of reflectance from 

the terrain features and is therefore more easily 

correlated with integrated terrain units than with 

differentiated units. Integrated terrain maps produced from Landsat images combine several terrain characteristics into each map unit, which 

then is more directly related to land use and to 

methods of land management than is any single 

characteristic.

Landsat data of a particular scene may be registered with a second set of Landsat data of the 

scene taken at a different time. Temporal variations between the two sets of data may then be 

measured quantitatively by a computer or qualitatively through use of a simple optical device. Landsat data collected since 1972 are available for most 

areas of the world, although coverage of areas far 

from ground-receiving stations may be sparse. An 

early Landsat image of an area may be used as a 

relative baseline with which to compare recent 

changes.

Remotely sensed data may be used in a digital 

format to calculate statistical information. The information obtained may be recorded as a histogram, a graph, or a new image. Hielkema (1977) 

uses principal component analysis for monitoring 

arid land vegetation. He finds that the third principal component highlights vegetation, and that

combining the three principal components into a 

new FCC shows vegetation better than does a regular FCC. He feels that vegetation changes may be 

closely monitored with this method. Lodwick 

(1979a) equates the second principal component 

with "greenness," the quality and quantity of vegetation, and suggests that changes in the second 

principal component may reflect changes in ecology caused by seasonal variations or by human 

interference.

Thompson and Wehmanen (1977, 1978) use 

transformed Landsat digital data to calculate a 

Green Index Number (GIN). The index number 

represents the percentage of picture elements in a 

Landsat scene having a "Green Number" greater 

than 15. A "Green Number" is a computer-derived 

measure of the amount of green vegetation present 

in a pixel; zero indicates bare soil and 15 indicates 

good vegetative cover. A plot of the GIN versus 

time for a normal segment of land follows a predetermined curve. Any deviation from this curve indicates that the area is undergoing drought. The 

method has been used to monitor agricultural 

areas but has not yet been applied to arid-land 

native vegetation.

Robinove and others (1981) use Landsat digital 

data to calculate albedo changes of arid terrain in 

Utah. Using registered multitemporal digital 

Landsat data, they calculate albedo differences in 

percentage and produce an image displaying the 

albedo increase or decrease. They find that many 

of the phenomena that tend to lower productivity 

of arid-land ecosystems will tend to make the land 

brighter on the image. These phenomena include 

decreased density of vegetation, increased erosion, 

and movement and deposition of wind-blown materials. Phenomena that increase productivity of 

arid-land ecosystems may tend to darken the land. 

These include increased density of vegetation and 

increased soil moisture. This monitoring system 

provides data on whether the land in a given area 

has brightened or darkened over a given period of 

time; these data may then be calibrated with 

ground data collected only in those areas where 

change has occurred. This approach provides a 

cost-efficient means of using remotely sensed data 

and, at the same time, provides for the acquisition 

of quantitative ground data at critical points.

The application of data from other imaging and 

nonimaging orbital sensors to desertification 

studies needs to be further investigated. Nimbus 

data of northern Africa have been used by Allison 

(1977) and Obuolowu (1977) to study moisture
patterns and vegetation boundaries. McCauley 

and others (1979) used Geostationary Operational 

Environmental Satellite (GOES) images to locate, 

measure, and study two dust plumes.

Blom and others (1979) compare Seasat synthetic aperture radar images of the Algodones 

dunes and Sonora dunes in southwestern North 

America with Landsat return beam vidicon images and aerial photographs. Their results suggest 

that the morphology of the larger dune features is 

well seen on the radar images. Comparison of ascending and descending passes indicates some differences in the signatures between the two returns.

Few studies have been done on the applicability 

of orbital photographs (rather than images) to 

desertification, partly because few repetitive orbital photographs are available. Pesce (1968) 

traces the southward migration of sand in Libya 

by analyzing Gemini photographs. Slezak and ElBaz (1979) use a zoom transfer scope to superimpose two orbital photographs taken several 

years apart to detect temporal changes of arid regions. They find an increase of vegetation west of 

the Nile River delta of approximately 1100 km2 in 

10 years. Few vertical or near-vertical orbital photographs are available for these types of studies, 

however, and further work must await the launch 

of the space shuttle which will provide photographs from the Large Format Camera.

AERIAL REMOTE SENSING

Aerial photographs and data also may be used to 

provide information on desertification. Gwynne 

and Croze (1975a) and Croze and others (1978) suggest that systematic reconnaissance flights can be 

used for ecological monitoring and resource assessment. Other sensors including radar (Batlivala and Ulaby, 1977) and infrared scanners may 

be used to monitor soil moisture and other desertification indicators.

Dejace and others (1979) mapped soil moisture 

and evaporation from day and night thermal images and visible light photographs. They conclude 

that a rapid variation of albedo or of surface 

roughness may affect the results of the measurement unless the variations are corrected at an individual pixel level.

Millard and others (1977) measured crop canopy 

temperatures with thermal-infrared and colorinfrared systems. They use the data to calculate a 

stress-degree day (SDD) and believe it indicates 

plant water needs and may be used to determine 

irrigation scheduling. The results establish the superiority of thermal-infrared images to colorinfrared photographs for such work.

To plan a study of desertification based on remote sensing methods, the user must consider 

from what altitude the data should be collected, 

based on the minimum resolution requirement for 

the project and the scale, and the cost of obtaining 

the data. When the scale has been determined, the 

user must decide the type of data to be used and 

the format of the data.

CONCLUSIONS

Remote sensing methods, both orbital and aerial, are valuable for locating, assessing and monitoring areas of desertification, but they must be 

used in conjunction with ground-collected data. 

An appropriate combination of the two will result 

in data that will provide a basis for planning and 

decisionmaking. The most efficient approach is to 

use remote sensing methods to detect areas of desertification or areas where the terrain has changed 

and to use ground methods to identify the cause of 

change and the possible remedial actions.

The user must also consider the fact that remote 

sensing methods are quite inexpensive per unit of 

data as compared to ground methods. The rationale for the use of remote sensing methods is to 

minimize the amount of ground data needed to 

ensure the validity of the remotely sensed data.

The application of remotely-sensed data to 

desertification studies is in the experimental 

stage. More research is needed on the use of such 

data to identify indicators of desertification and 

how they reflect the processes; on the rates of degradation or reclamation; on identifying a base for 

measuring the process; and on data presentation 

formats.

Although remote sensing methods have been 

used in studying desertification processes, the 

choice of methods, or the combination of methods, 

that is most practical and efficient for routine 

monitoring of both large and small areas needs 

additional investigation. The potential contribution of non-Landsat satellite sensors and quantitative information on how much field work is 

necessary to support a given sensor in a given area 

are unknown.

The annotated bibliography is restricted to papers concerning changes in arid and semiarid 

lands and their monitoring by remote sensing 

methods. It purposely does not attempt to cover 

the voluminous literature on the use of remote


Bentley, R. G., 1978, Recommendations for a study 

to test the feasibility of monitoring indicators 

of desertification in West Africa using ground 

data, large-scale aerial photography and 

Landsat data: Washington, B.C., U.S. Agency 

for International Development, 36 p. 

A research project is designed to monitor the 

process of desertification using remote sensing as 

a tool. The author discusses the social situation in 

the Sahel, implications for U.S. programs, and 

makes recommendations for the U.S. AID program. A literature review is included.

Bentley, R. G., Salmon-Drexler, B. C., Bonner, W. 

J., and Vincent, R. K., 1976, A Landsat study of 

ephemeral and perennial rangeland vegetation and soils: Washington, D.C., Bureau of 

Land Management, 234 p. 

Landsat data are processed by computer to map 

vegetation characteristics of perennial rangeland 

in Montana and of ephemeral rangeland in Arizona. The choice of processing techniques depends 

on prescribed mapping tasks and site conditions. 

Techniques such as maximum likelihood classification are useful for recognizing the plant communities in Montana. Other techniques such as density 

slicing of images are more effective in sparsely 

vegetated Arizona. Landsat sensors are more sensitive to differences between plant communities 

based on percent of vigorously growing vegetation 

than to actual physical or spectral differences 

among species. An operational system for the Bureau of Land Management is recommended.

Berkofsky, L., 1976, Effect of variable surface albedo on the atmospheric circulation in desert 

regions: Journal of Applied Meteorology, v. 15, 

p. 1139-1144.

A desert circulation model is developed which 

includes a vertically parameterized boundary 

layer. The model is used to investigate circulation 

in the northern Negev. The vertical velocity at the 

tip of the boundary layer is related to net radiative 

heating (function of albedo), convective heating, 

and ground friction. The author's calculations imply that lowering surface albedo may lead to increased vertical velocity and increased rainfall.

Berry, L., and Ford, R. B., 1977, Recommendations 

for a system to monitor critical indicators in 

areas prone to desertification: Worcester, 

Mass., Clark University, 187 p.

An interlinked monitoring system is proposed to 

join together a small and selective global monitoring program with local, national, and regional 

monitoring activities. At the global level, albedo, 

duststorms, rainfall, soil erosion, sedimentation, 

and salinization should be monitored. The authors 

recommend the use of satellite images for all 

levels of monitoring.

Blom, R. G., Daily, M. L, Elachi, C., and Saunders, 

R. S., 1979, Analysis of Seasat SAR images of 

sand dunes, in Reports of Planetary Geology 

Program, 1978-79: National Aeronautics and 

Space Administration, Technical Memorandum 80339, p. 359-361.

Seasat SAR (synthetic aperture radar) images 

of the Algodones dunes, southeastern California, 

and the Sonora dunes, northwestern Mexico, are 

compared with Landsat 3 return beam vidicon 

data and aerial photographs. Results show that 

the dune morphology is well expressed in the radar 

images, and a comparison of images from ascending and descending passes indicates a difference in 

signatures between the two types of passes.

Brera, A., and Shahrokhi, F., 1978, Application of 

Landsat data to monitor desert spreading in 

the Sahara region: International Symposium 

on Remote Sensing of Environment, 12th, 

Proceedings, p. 1329-1335. 

Desert dunes in Africa are now advancing at the 

rate of 30 miles per year in spite of the fact that 

sand fixation and afforestation methods have been 

undertaken by many countries. Satellite images 

are used to analyze and define factors relating to 

dune movement, formation, and growth. The authors use 1972-77 digital Landsat data of a test 

site in the Libyan Desert to identify and map 

distinct units on the ground. From comparison of 

temporal data, the authors conclude that global 

surveillance of the status of dryland ecosystems 

and land use can be achieved most economically 

with Landsat images.

Casimir, M.J., Winter, R.P., and Glatzer, Bernt, 

1980, Nomadism and remote sensing: animal 

husbandry and the sagebrush community in a 

nomad winter area in western Afghanistan: 

Journal of Arid Environments, v. 3, p. 231-254. 

The authors use Landsat digital data to augment field-collected data on the amount and types 

of biomass and herd animals in a winter grazing 

area of the Pashtan nomads. They calculate the

8
available annual food plant growth and compare it 

with the estimated herd requirement and the estimated fuel requirement. During the 1976-77 winter, 23-32 percent of the annual food plant growth 

was consumed in the nomad economy. The authors 

find that the first principal component shows more 

detail than do any of the original Landsat bands, 

and that unfiltered data are best for classification 

and statistics.

Centre National de la Recherche Scientifique, 1978, 

Contribution a 1'analyse ecologique des zones 

arides de Tunisie avec 1'aide des donnees de la 

teledetection spatial. (Contribution to the 

ecological analysis of the arid zones of the 

Tunisia area using spatial remote sensing): 

Experience ARZOTU, Rapport final 1975-78, 

Centre National de la Recherche Scientifique, 

Montpellier, France, 222 p. 

The arid zone of Tunisia (ARZOTU) experiment, 

based on the use of Landsat data, sought to achieve 

small-scale cartographic mapping of ecological 

zones, land use, and desertification conditions, and 

to determine the usefulness of multitemporal satellite data for regional ecological modeling. Based 

on the results of the experiment, a comprehensive 

view is presented of the potential uses of spatial 

remote sensing techniques in the arid areas along 

the northern fringe of the Sahara. Recommendations are made for the implementation of a spatial 

remote sensing experiment, in view of the opportunities for using these techniques in developing 

countries of the Mediterranean arid zone. The report contains a bibliography of 230 items.

Charney, J. G., 1975, Dynamics of deserts and 

drought in the Sahel: Quarterly Journal of 

the Royal Meteorological Society, v. 101, p. 

193-202.

The high albedo of a desert contributes to a net 

radiative heat loss relative to desert surroundings. 

The horizontal temperature gradients on desert 

borders induce a frictionally controlled circulation 

that imparts heat aloft and maintains thermal 

equilibrium through a sinking motion and adiabatic compression. This gradient is superimposed 

on the descending branch of the mean Hadley circulation, but it is more intense. The author argues 

that reduction in vegetation increases albedo, 

causing the sinking motion and perpetuating the 

arid conditions. A biogeophysical feedback mechanism leads to instabilities on borders of deserts 

which may be set off by anthropogenic influences.

The author concludes that the Sahel drought may 

have been caused by overgrazing.

Coiner, J. C., 1980, Using Landsat to monitor 

changes in vegetation cover induced by desertification processes: International Symposium 

on Remote Sensing of Environment, 14th, 

Ann Arbor, Mich., Proceedings, p. 1341-1352. 

Using a test site on the Niger River delta in 

Mali, west Africa, the author compares the correlation coefficient for two Landsat multispectral 

scanner bands on images acquired in 1973 and 1975 

to produce a vegetation status map for each of the 

2 years, and a vegetation change map.

Colwell, R. N., and Carneggie, D. M., 1971, Applications of remote sensing to arid-land problems, 

in McGinnies, W. G., and others, eds., Food, 

fiber, and the arid lands: Tucson, University of 

Arizona Press, p. 173-186. 

The authors discuss the need for resource surveys to manage and properly exploit arid and 

semiarid regions of the world. The most efficient 

type of resource survey would involve remote sensing from aircraft or spacecraft. These remote 

sensing methods are especially applicable because 

of the relatively cloud-free conditions in arid 

lands. After reviewing the specifications of remote 

sensing and the type of information desired, the 

authors conclude that the best technique is multistage, multispectral sampling utilizing aircraft, 

spacecraft, and ground data. The characteristics of 

infrared Ektachrome film are discussed, and a 

photointerpretation key of the following major 

land use categories is presented: urban lands, agricultural croplands, uplands, rangelands, bottomlands (stream channels and washes), and salt flats. 

Photographs of the Phoenix, Ariz., area are included to illustrate these categories. Large-scale aerial 

photographs are used to illustrate the problems of 

identifying vegetation by subsampling (from Paylore, 1976a).

Condon, R. W., 1978, Land tenure and desertification in Australia's arid lands: Search, v. 9, no. 

7, p. 261-264.

The author discusses ways in which the views 

and activities of early pastoral peoples and land 

administrators in Australia contributed to severe 

pasture degeneration and erosion of the more 

fragile landscapes. He describes factors that 

have modified the rate of degeneration since the 

widespread drought of the 1940's including lease


and studying their geomorphic environment. The 

authors find that crescentic dunes occur mostly in 

depressions. Where belts of longitudinal dunes 

cross escarpments, they break up into fields of 

crescentic dunes which move rapidly to inundate 

roads and agricultural fields.

El-Etr, H. A., and Yousif, M. S. M., 1978, Utilization of "Landsat" images and conventional 

aerial photographs in the delineation of some 

aspects of the geology of the central Eastern 

Desert, Egypt (abs.): Precambrian Research, 

v. 6, p. A14-A15. 

The applications of Landsat images to fluvial

features and drainage patterns in the Eastern

Desert are discussed.

El-Shazly, E. M., Hady, M. A. A., and El-Kassas, 

I. A., 1977a, Delineation of land features in 

Egypt by Landsat satellite images: Annual 

Remote Sensing of Earth Resources Conference, 6th, Tallassee, Tennessee, Proceedings, 

p. 277-294.

Several examples are presented of the application of Landsat images to analyses of land features 

in Egypt. In one case, the authors compare sanddune belts interpreted from Landsat images with 

those mapped by the survey of Egypt 45 years previously and find that the belts have moved a considerable distance eastward.

El-Shazly, E. M., Hady, M. A. A., and El-Shazly, 

M. M., 1977b, Groundwater studies in arid areas in Egypt using Landsat satellite images: 

International Symposium on Remote Sensing 

of Environment, llth, Ann Arbor, Mich., Proceedings, p. 1365-1372.

Landsat images are used to determine the nature of geological and lithologic units, structural 

lineaments, present and past drainage systems, 

and the distribution and form of water pools. The 

images are also used for analyzing geomorphic 

units, weathering surfaces and other weathering 

phenomena, desert soils, sand dunes, and salt 

crusts and other surface expressions of salinization. In the northern Western Desert, ground 

water comes to the surface along fault lines and 

fracture systems, and thus, analysis of Landsat 

images may help locate ground water supplies. The 

authors use positive transparencies of bands 5 

and 7, false-color composites, and computercompatible tapes to delineate the water-bearing 

units.

El-Shazly, E. M., Hady, M. A. A., El-Shazly, M. M., 

El-Ghawaby, M. A., Salman, A. B., El-Kassas, 

I. A., Khawasik, S. M., El-Rakaiby, M. M., and 

El-Amin, H., 1978, Jonglei canal project, 

Sudan, a Landsat imagery approach: International Symposium on Remote Sensing of 

Environment, 12th, Ann Arbor, Mich., Proceedings, p. 1563-1572.

Landsat images are used for regional mapping 

and study of the Jonglei Canal Project, and are 

especially valuable in view of the inaccessibility of 

the area during the rainy season. Using Landsat 

images, low reconnaissance aerial photographs 

and ground truth and laboratory analyses, maps 

are constructed to show geological and environmental units, structural lineations, lineation density, surface drainage, surface water bodies, 

ground-water potential, soils, land use, vegetation, 

and infrastructure. Analysis of Landsat images 

provided a regional picture of a 165,000-km2 area 

at a scale of 1:500,000 in less than 18 months.

El-Shazly, E. M., Hady, M. A. A., El-Shazly, M. M., 

El-Ghawaby, M.A., Khawasik, S. M., Haraga, 

A.A., Sanad, S., and Attia, S. H., and others, 

1978, Application of Landsat imagery in the 

geological and soil investigations in the central Western Desert, Egypt: International 

Symposium on Remote Sensing of Environment, 12th, Ann Arbor, Mich., Proceedings, p. 

857-866.

Landsat images are used to produce soils, geologic, environment, lineament and drainage maps 

of the central Western Desert at a scale of 

1:500,000. Ground truth data, including soil profiles and lithostratographic sections, are used to 

verify interpretations. The authors use the maps 

to select and rate the most appropriate locations 

for desert development.

Fryberger, S. G., and Ahlbrandt, T. S., 1979, Mechanisms for the formation of eolian sand seas: 

Zeitschrift fur Geomorphologie, v. 23, p. 

440-460.

The authors compare sand features visible on 

Landsat images with surface wind data from 

weather stations to support assertions that large 

quantities of sand can be driven long distances 

across deserts by wind. By comparing regional 

wind regimes (including potential sand-moving 

wind energy and trends in direction of sand drift) 

to the positions of modern sand seas, the authors 

find that regional systems of sand drift may

12
deliver much of the sand. The authors feel that in 

some areas regional wind systems are as important in depositing sand as are aqueous systems.

Ghose, Bimal, Kar, Amal, and Husain, Zahid, 1979, 

The lost courses of the Saraswati River in the 

Great Indian Desert: new evidence from 

Landsat imagery: The Geographical Journal, 

v. 145, p. 446-451.

The authors use Landsat band 7 images to trace 

abandoned courses of the Saraswati River in 

northwestern India. The former drainage systems 

are represented on the images by belts of discontinuous patches of dark gray. Field investigations 

confirm the existence of the abandoned courses 

and the relationship of good water wells to the 

courses. The authors suggest that either advancing sand and aridity or mild tectonism is responsible for the westward shift of the river.

Glantz, M. H., 1977, The U.N. and desertification: 

dealing with a global problem, in Glantz, M. 

H., ed., Desertification environmental degradation in and around arid lands: Colorado, 

Westview Press, p. 1-15. 

Using Rapp's (1974) definition of desertification, 

the author describes the process on a global scale, 

although he argues that desertification is primarily national in cause and national in effect. He cites 

as evidence satellite images showing changes 

across national boundaries. Desertification 

from an international and a national viewpoint is 

discussed.

Gonzales, Martin, 1978, Use of indicators in the 

Mexican experimental station (abs.): American Association for the Advancement of Science, National Meeting, 144th, Washington, 

D.C., Proceedings, p. 52-53. 

The applications of the United Nations indicators for desertification to test areas of Mexico 

are discussed. The author reports on the success of 

working parties in different locales who are comparing indicators on a regional basis.

Gwynne, M. D., and Croze, Harvey, 1975, East African habitat monitoring practice: A review of 

methods and application, in Pagot, J. R., ed., 

Evaluation and mapping of tropical African 

rangelands Seminar: Bamako, Mali, Proceedings, p. 95-135.

A review is presented of methods used to monitor habitats, the results of the various methods,

and the applicability of the results. An ecological 

monitoring system must be designed to collect 

data on environment (climate, topography, soils, 

flora, and hydrology), wildlife, and human and 

domestic animal land use patterns. Aerial 

photographs, ground truth data, and satellite images are all considered applicable to ecological 

monitoring.

Hacker, R. B., 1978, Use of large-scale aerial photographs for ecological studies in a grazed arid 

ecosystem: International Symposium on Remote Sensing of Environment, 12th, Ann 

Arbor, Mich., Proceedings, p. 1895-1908. 

Color aerial photographs at a scale of 1:250 are 

used to obtain plant inventories for six study sites 

in a multilayer arid-zone community. Species are 

divided into size classes based on canopy area. 

Variations in grazing pressure are the major factor influencing community patterns in the three 

sites. Responses of the various plant species to 

grazing are defined.

Hady, M. A., El-Shazly, E.M., and Myers, V., 1979, 

The use of remote sensing for monitoring 

desertification processes and natural resources in desert and arid lands: Advances in 

Deserts and Arid Land Technology and Development, v. 1, Harwood academic publishers, 

New York, p. 399-410.

The objectives of a monitoring program for 

desertification are: to assess existing ecological 

and resource conditions, to detect physical indicators of desertification, and to observe changes representative of improvement or deterioration of 

natural resources. The authors believe the solutions to the desertification problem must be found 

on a regional or national level. The authors suggest Landsat and National Oceanic and Atmospheric Administration (NOAA) satellite images 

be used for monitoring desertification signatures, especially with regard to the amount of soil 

moisture.

Hare, F., Kates, R., and Warren, A., 1977, The 

making of deserts: climate, ecology, and society: Economic Geography, v. 53, p. 332-346. 

The authors assert that desertification, the aggravation or extension of natural conditions, is 

caused by society's search for secure livelihoods in 

dry environments. Natural drought accentuates 

but does not cause the process. The authors believe 

that desertification is difficult to detect at a

13


the Carex physodes marks the end of the optimal 

period. Panchromatic, infrared, and false-color 

films are suggested for multiband photographs. 

The author prefers wavelengths of 400-525 nanometers (nm) and 600-674 nm for deserts, and 

600-675 nm and 750-850 nm for cultural features. 

The author discusses wind erosion maps, maps of 

sand types suitable for afforestation, maps of forests damaged by insects, and maps showing the 

distribution of harmful substances and salts in 

water and soils.

Kharin, N. G., 1977, Remote-sensing techniques 

and the monitoring of desertification processes in arid areas: Moscow, Turkmen Academy of Sciences, Institute of Deserts, 31 p. 

The author presents a brief survey, including 

definitions and terms and technical means used for 

monitoring of desertification processes. The author uses an increase in arid territories of Turkmeniya as an example of climatic desertification 

caused by the drying up of vegetation in years of 

scanty precipitation, followed by the emergence of 

moving sands. Anthropogenetic desertification 

may be found near water wells, population centers, 

roads, and other similar areas. Desertification 

may also be caused by natural calamities, such as 

floods of unusual scope or fires. Using these three 

types of desertification, the author illustrates how 

the use of remote sensing techniques can contribute to desertification monitoring.

Kowalik, W. S., Marsh, S. E., and Lyon, R. J. P., 

1978, The effect of several atmospheric corrections on Landsat 5/4 ratios: Palo Alto, 

Calif., Stanford University, Technical Report 

78-11, 41 p.

Ratios of multispectral scanner bands 5 and 4 

from Landsat 2 computer-compatible tapes are 

compared for several test sites including 10 typical 

desert surfaces. Atmospherically corrected ratios, 

whether corrected by conversion to reflectance or 

by subtraction of dark-value path-radiance, are on 

the average superior to raw Landsat band 5 and 4 

ratios except in areas of poor illumination or low 

reflectance. In these areas errors are introduced to 

ratios of small numbers by the atmospheric 

corrections. To compensate for these errors, the 

authors suggest a differential atmospheric correction using the path-radiance subtraction for 

high-digital numbers and a progressively lowersubtracted value for lower radiances. This approach avoids the apparent error introduced to

ratios of small numbers by the atmospheric correction and thus provides more accurate calculations for poorly illuminated or low-reflectance 

sites.

Le Houerou, H. N., 1976, Rehabilitation of degraded arid lands, in Rapp, A., Le Houerou, H. 

N., and Lundholm, B., eds., Can desert encroachment be stopped? A study with emphasis on Africa: Swedish Natural Science Research Council, Ecological Research Bulletin, 

no. 24, p. 189-205.

Based on the premise that desertification is 

man-induced but aggravated by climatic circumstances, any measure for halting further loss of 

productivity will have to interfere with human activities. The author believes that cures for desertification have been known for a long time. Methods 

for biological recovery in desertified areas include: 

rural afforestation, sand-dune stabilization, soil 

water budget improvement, and better management of saline soils, and waters. Satellite images 

are considered helpful for monitoring desertification and evaluating the success of reclamation 

projects.

Lodwick, G. D., 1979, Measuring ecological changes 

in multitemporal Landsat data using principal components: International Symposium 

on Remote Sensing of Environment, 13th, 

Ann Arbor, Mich., Proceedings, p. 1131-1141. 

Seven Landsat images of upper Hunter Valley, 

New South Wales, a nonagricultural countryside, 

are used for principal component analysis. The author finds that the first component is "brightness," 

related to the form and nature of the terrain, particularly its aspect. The second principal component reflects "greenness," the quality and quantity 

of vegetation. Changes in the principal components reflect changes in the ecology caused by 

seasonal changes or human influence.

Long, G., Lacaze, B., Deblissche, G., Le Floc'h, E.,

Sta-M' Raid, M., Pontaniev, R., and Le Cocq,

A., 1977, Experimentation sur 1'utilisation des

donnees Landsat pour 1'etude ecologique des

zones arides de Tunisie (Arzotu experiment):

Canadian Symposium on Remote Sensing,

4th, Quebec, 1977, Proceedings, p. 365-375.

The report summarizes the experience of the

ARZOTU experiment, begun in 1974, in several

desert areas of Tunisia. The ARZOTU studies cover

an area of approximately 50,000 km2 between the

16
100 and 350 mm rainfall isohyets. Objectives of the 

experiment included an inventory of surface landforms, soils, vegetation, and ecology, as well as 

cartographic potential. Results of the inventory 

are tabulated by area. Applications of remote 

sensing techniques are described.

McCauley, J. F., Breed, C. S., Grolier, M. J., and 

MacKinnon, D. J., 1979, The U.S. dust storm of 

February, 1977, in Pewe, T. L., ed., Desert 

dust: origin, characteristics, and effect on 

man: Geological Society of America, Special 

Paper (in press).

GEOS-1, a geostationary weather satellite, imaged two dust plumes of the first winter storm of 

1977. The location, direction, and obscured ground 

surface were measured from the satellite images. 

The vastness of this storm suggests that atmospheric transport of dust eastward from the Great 

Plains to the Atlantic Ocean may be of sedimentologic significance.

McGinnies, W. G., 1970, An annotated bibliography and evaluation of remote-sensing publications relating to military geography of 

arid lands: U.S. Army Earth Sciences Laboratory, Technical Report 71-27-ES, 107 p. 

A 355-reference annotated bibliography is presented of remote-sensing publications related to 

military geography of arid lands. The publication 

includes summary tables of the applications of 

varied remote sensing techniques to terrain, 

groundwater, soils, cultural features, flora, fauna, 

weather and climate, coastal zones, and general 

geography.

McGinnies, W. G., 1974, A study to explore the use 

of orbital remote sensing to determine native 

arid plant distribution: Tucson, University of 

Arizona, Office of Arid Land Studies, 36 p. 

Results of the research include a method for 

determining the reflectivities of natural areas 

from ERTS data taking into account Sun-angle 

atmospheric effects on the radiance seen by the 

satellite sensor. Ground truth spectral signature 

data for various types of scenes, including ground 

with and without annuals and various shrubs, are 

collected. Large areas of varnished desert pavement are visible and mappable in ERTS and highaltitude aircraft images. A large-scale and a 

small-scale vegetation pattern are found to be correlated with presence of desert pavement. A comparison of radiometric data with video recordings

shows quantitatively that for most areas of desert 

vegetation, soils are the most influential factor in 

determining the signature of a scene. Additive and 

subtractive image-processing techniques are applied in the darkroom to enhance vegetational aspects of ERTS images (from Paylore, 1976).

McKee, Edwin, 1974, An investigation of major 

sand seas in desert areas throughout the 

world: ERTS Symposium, 3d, Washington, 

B.C., v. 1, Proceedings, NASA SP-351, p. 

655-679.

Landsat images are used to investigate sand 

seas on a global scale. One of the objectives of this 

study is to gain insight into the controls of sand 

migration. Fifteen major sites in the Eastern 

Hemisphere and three in the Western Hemisphere 

are examined on mosaics of false-color prints. The 

author proposes that sand bodies be classified into 

five principal types: parallel straight or linear, 

parallel wavy or crescentic, star or radial, parabolic, and sheet or stringer types. Each group has 

numerous variations. Controlling factors in forming the types of sand bodies are: wind direction 

and strength, topography, vegetation, moisture, 

available sediment, and distance from source. The 

author attempts to recognize and delineate these 

factors. Ground investigations are used to determine the internal structures of sand masses.

McKee, E. D., Breed, C. S., and Fryberger, S. G., 

1977, Desert sand seas, in Skylab Explores the 

Earth: Johnson Space Center, NASA SP-380, 

p. 5-48.

The authors report on the results of Skylab 4 

analysis of desert sand seas. Handheld camera 

photographs from space and visual observations 

are used for studying regional patterns, preparing 

maps, and classifying eolian sand deposits. This 

information may contribute to understanding 

dune movement and predicting future environments conducive to sand deposition.

McKee, E. D., Breed, C. S., and Harris, L. E., 1973, 

A study of morphology, provenance, and 

movement of desert sand seas in Africa, Asia, 

and Australia: Symposium on Significant Results Obtained from ERTS-1, NASA Proceedings v. 1, p. 291-303.

Major types of desert sand seas are classified on 

the basis of morphologic pattern and lineation. 

The authors study the influence of Sun angle, atmospheric conditions, and season on the images

17


and infrared images, the author distinguishes between areas of sand deflation and accumulation.

Nossin, J. J., 1977, An integrated survey of the 

region Sousse, Tunisia: International Institute for Aerial Survey and Earth Sciences 

(ITC) Journal, v. 2, p. 336-357. 

The paper outlines a multidisciplinary study of 

the Governorate Sousse, Tunisia, to identify development alternatives based on investigations of the 

land, water, and human resources. The author 

projects the benefits and consequences of each of 

these alternatives to 1986. The availability of 

water is the chief constraint on industry, tourism, 

and agriculture. A linear programing model is 

used to outline the basic materials necessary for 

policy development.

Obuolowu, A., 1977, Quantitative interpretation of 

remotely sensed data as a key to mapping vegetative patterns in the western Sudan: Geographical Journal, v. 1.5, p. 13-20. 

Monthly high resolution infrared radiometer 

(HRIR) data from Nimbus 3 are used to analyze 

changes in vegetation boundaries over the Sudan. 

The author suggests that the changes in vegetation are caused by changes in soil-moisture 

content which is controlled by the prevailing meteorological conditions. The author briefly reviews 

the capabilities of satellite remote sensing 

systems.

Otterman, Joseph, 1974, Baring high-albedo soils 

by overgrazing: a hypothesized desertification 

mechanism: Science, v. 186, p. 531-533. 

The author compares the albedos of soils 

denuded by overgrazing with those of regions covered by vegetation and shows that denuded surfaces are cooler. The cooler surfaces may result in 

a decreased lifting of air necessary for cloud formation and precipitation, leading to regional 

desertification.

Otterman, Joseph, 1975, Reply to Jackson, R. D. 

and Idso, S. B.: Science, v. 189, p. 1013-1015. 

The author discusses the thermal characteristics of healthy leaves as a function of evapotranspiration and high albedo in the infrared 

portion of the electromagnetic spectrum. He discusses the contrast in Landsat band 7 reflectance 

between the Sinai and Negev Deserts and attributes the high albedo of the Sinai to the bare unstabilized soil.

Otterman, Joseph, 1977, Anthropogenic impact on 

the albedo of the Earth: Climatic Change, v. 1, 

p. 137-155.

The author analyzes the impact of people and 

animals on the surface albedo of the Earth. Low 

albedo is a result of dark plant debris accumulating on the crusted soil surface. The higher 

albedo is produced when overgrazing results in a 

trampled, crumbled soil. The author believes that 

overgrazing has a significant regional and global 

effect, and may have raised the surface albedo of 

the Earth by as much as 10 percent. He recommends seasonal mapping of surface albedo from 

satellite data.

Otterman, Joseph, 1978, Point sources and streaks 

of dust storms: a study of Landsat images and 

some inferences: Israel Meteorological Research Papers, v. 2, p. 233-243. 

Analysis of Landsat images of intense dust 

storms indicates that the dust originates in point 

sources and flows in nearly horizontal streaks that 

maintain their shape in a horizontal flow for up to 

100 km. Particles are lifted by saltation which 

then increases friction at the surface. This increase explains the prevalence of point sources. 

The author suggests that prevention and countermeasures may be more effective in the case of a 

horizontal-flow regime than in the case of dust 

storms created by descending air masses.

Otterman, Joseph, and Fraser, R.S., 1976, Earthatmosphere system and surface reflectivities 

in arid regions from Landsat MSS data: Remote Sensing of Environment, v. 5, p. 247-266. 

The authors compute ratios of the Earthatmosphere system (space) directional reflectivities in the nadir direction to the surface. Ratios 

are presented in graphs in which two water-vapor 

levels are plotted as a function of surface 

reflectivity at various Sun angles. The authors calculate reflectivities for a vertical direction in selected arid regions in Asia, Africa, and Central 

America from spectral-radiance levels of the MSS. 

They also compute surface reflectivities and estimate surface albedo for the entire solar spectrum.

Paylore, Patricia, ed., 1976a, Desertification: a 

world bibliography: Tucson, University of Arizona, Office of Arid Land Studies, 644 p. 

This annotated bibliography of desertification is 

divided into the following sections: Worldwide, 

Saharan Region and Sahel, East Africa, Southern

20
Africa, Middle East, U.S.S.R., Pakistan, India, 

Australia, South America, and North America. 

The sections are subdivided into individual countries. Each section contains a keyword and author 

index.

Paylore, Patricia, ed., 1976b, The Sonoran desert: a 

retrospective bibliography: Tucson, University of Arizona, Office of Arid Land Studies, 

422 p.

The report contains a 777-entry annotated bibliography of papers on the Sonoran desert. Entries 

are listed by main subject and are cross-indexed. 

Seven entries are listed under remote sensing.

Pesce, Angelo, 1968, Gemini space photographs of 

Libya and Tibesti: Tripoli, Libya, Petroleum 

Exploration Society of Libya, 81 p. 

The author uses Gemini photographs to trace a

southward migration of sand and sand dunes and

to recognize hydrographic systems.

Place, John, 1976, Monitoring change in land use 

over large regions, in U.S. Geological Survey 

Professional Paper 929, p. 230-233. 

Landsat images of the Phoenix, Ariz., area are

used to update maps and to identify the areas of

greatest change in which more intensive survey

techniques may then be applied.

Rapp, A., 1974, A review of desertification in Africa: water, vegetation, and man: Stockholm, 

Sweden, Secretariat for International Ecology, SIES Report no. 1, 77 p. 

The author concludes that actual desertization, 

which term he prefers to desertification, is mainly 

induced as a result of overgrazing, overcultivation, 

wood cutting, and burning. The overexploitation 

by man destroys the plant cover beyond the required minimum coverage for protection of the soil 

against rapid soil erosion by water or wind. The 

author recommends surveying and monitoring of 

selected transects in Africa and elsewhere, as a 

basis for short-term and long-term actions. He also recommends using pilot trial plots of land to 

demonstrate ecologically sound methods of land 

use. He focuses particularly on analysis of quantity and type of soil particles in dust storms from 

drylands and desert areas by means of satellite 

images and ground checking (from Paylore, 

1976a).

Rapp, A., 1976, Regional studies and proposals for 

development: in Rapp, A., Le Houerou, H. N., 

and Lundholm, B., eds., Can desert encroachment be stopped? A study with emphasis on 

Africa: Swedish Natural Science Research 

Council, Ecological Bulletin no. 24, p. 155-164. 

Photographs from aerial reconnaissance surveys are used to map the desert boundaries and 

study vegetation in the Sudan.

Reining, Priscilla, ed., 1978a, Desertification papers: Washington, D.C., American Association for the Advancement of Science, 141 p. 

The editor includes six background papers and 

four papers presented after the 1977 Nairobi Seminar on Desertification. The papers address the issues of measuring and monitoring desertification.

Reining, Priscilla, ed., 1978b, Handbook on 

desertification indicators: Washington, D.C., 

American Association for the Advancement 

of Science, 141 p.

At the 1977 United Nations Seminar on 

Desertification, a limited number of key signs or 

indicators of desertification were identified. The 

editor lists and discusses these indicators and suggests two principal ways in which remotely sensed 

data from aircraft and spacecraft may be used in 

conjunction with the indicators to study desertification. The images may be used to define an area 

for a stratified area frame sample, or they may be 

used in conjunction with other data to detect or 

assess specific features.

Robinove, C. J., 1979, Integrated terrain mapping 

with digital Landsat images in Queensland, 

Australia: U.S. Geological Survey Professional Paper 1102, 39 p.

The author uses Landsat images to produce integrated terrain maps of Queensland, Australia. The 

integrated terrain mapping combines several terrain features into each map unit. The units are 

more directly related to uses of the land and to 

methods of land management than are the single 

features alone. Terrain brightness, as measured by 

Landsat scanners, represents an integration of reflectance from the terrain features and is therefore more correctable with integrated terrain 

units than with differentiated ones.

Robinove, C. J., Chavez, P. S., Jr. Gehring, D., and 

Holmgren, R., 1981, Arid land monitoring

21


Theme extraction, or supervised classification, 

of data from Landsat computer-compatible tapes 

is valuable for arid land mapping. The authors 

establish suitable themes using an unsupervised 

parallelepiped technique, and find that the mapping can be accomplished at considerable savings 

over conventional mapping techniques.

Verstappen, H. T., 1979, Drought susceptibility 

survey and the concept of monitoring landscape ecology: Symposium on Drought in Botswana, Hanover, N.H., University Press, 

Proceedings, p. 75-83.

Desertification is believed to be caused by the 

cumulative effect of an anthropogenous and a climatic factor. The anthropogenous factor is the 

inappropriate use of land, particularly when population is increasing. The climatic factor is associated with secular and seasonal fluctuations. Both 

factors are interrelated and may reinforce each 

other. A decrease in vegetative cover and the resulting increase in albedo results in subsiding air 

currents in the margins of deserts. Rainfall then 

decreases, and vegetation further decreases. National Oceanic and Atmospheric Administration 

satellite data indicate that a reversal of the process may take place in areas where vegetation has 

reappeared because of a reduction in the number 

of livestock during drought. The reappearance of 

vegetation may help to introduce natural precipitation after a drought. Landsat images are used to 

reveal major patterns and to survey key areas, 

followed by stereoscopic observations of aerial 

photographs and associated fieldwork.

Vinogradov, B. V., 1976, Desertification forms as 

shown on aerial and space photos, in Glantz, 

M. H., ed., Desertification Environmental 

degradation in and around arid lands: Colorado, Westview Press, p. 219. 

Desertification can be identified on aerial and 

space photographs. Temporal data are considered 

to be the most reliable for monitoring desertification. The spectral reflectance coefficient is one of 

the major keys for monitoring desertification. The 

value of the coefficient is inversely proportional to 

the projected vegetation cover at decreased soil 

moisture and increased concentrations of dust.

White, L. P., 1975a, Monitoring desertification 

from space: Cambridge meeting on desertification, Cambridge, England, Proceedings, p. 

28-31.

Photographs are useful for identifying smallscale individual changes in areas susceptible to 

desertification. However, such photographs are 

not useful for quantitative spectral measurements 

because the information they contain cannot be 

calibrated.

White, L. P., 1975b, Vegetation areas as indicators 

of changing environment: Cambridge meeting 

on desertification, Cambridge, England, Proceedings, p. 45-50.

Vegetation arcs, stripes, and ripples occur on 

flat to gently sloping surfaces where water moves 

as sheet wash in arid and semiarid environments. 

The author uses large-scale black-and-white and 

color aerial photographs to map the vegetation.

Williams, 0. B., Svidendoup, H., and Wilcox, D. G., 

1977, Australia: Gascoyne Basin An associated case study: U.N. Conference on Desertification, Nairobi, 1977, Conference Document 

A/conf. 74/12,177 p.

The Gascoyne Basin in western Australia, an 

area heavily grazed by sheep, has suffered severe 

rangeland degradation and erosion. Social, political, and economic aspects of the basin are 

described, and constraints to the control of desertification are noted with emphasis on practices to 

improve rangelands. Suggested programs include 

(1) reduction of sheep and removal of all livestock 

from seriously degraded areas, (2) renewal of certain perennial shrubs, (3) improved management 

and inspection of sheep and cattle stations, (4) 

monitoring of programs using large-scale aerial 

photographs and ground measurements, and (5) 

rangeland research and educational programs involving plant species identification and range 

assessment. Appendixes include information on 

pastoral leases, financial analysis for a typical station, general assessment of an individual station, 

and detailed description of rangeland types.

Worcester, B. K., and Dalsted, K. J., 1979, Application of remote sensing to detection of desertification processes, in Goodin, J. R., and 

Northington, D. K., eds., Arid land plant resources: Lubbock., Tex., International Center 

for Arid and Semi-Arid Land Studies, p. 

622-628.

Landsat data are excellent for monitoring desertification because they provide a broad synoptic view, repetitive coverage, nearly orthographic

24
scenes, and multispectral capabilities. Digital data 

are available for computer analyses. The objectives of a desertification monitoring program are 

to assess existing conditions, to detect physical indicators of desertification, and to observe changes 

representative of improvements or deterioration

of natural resources. Band 5 and false-color 

composite images show vegetation best, while 

bands 6 and 7 are better suited to hydrology. The 

authors believe that remote sensing methods 

are timely and cost-effective for monitoring 

desertification.

 it U.S. GOVERNMENT PRINTING OFFICE: 1981-341-614/240

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