Harlow J. HODGSON *(*) Principal Agronomist, Cooperative State Research Service, U.S. Department of Agriculture, Washington D.C. 20250, U.S.A.
The potentials for livestock to contribute to world food supply are very great, and the dependence on rangelands will increase as world population and food needs increase. Application of improved technology, much of it already available, offers great promise for substantially increasing productivity of rangelands of tropical Africa. Rational application of such technology will depend upon understanding of ecological potentials and limitations of rangeland sites. Rangeland survey and evaluation provides the basis for that understanding. There is need for summarization and collation of survey information already available as a basis for rapid increase in technological application and food production.
World population grows at a rapid rate. It refuses to halt its steady increase - at least for a while. Millions of people today have little or nothing to eat; millions more have diets inadequate in quantity or quality. It will be the same tomorrow, and the day after; perhaps it will be so for a long time to come.
The most viable potential for easing this situation, at least over the long term, lies in increasing agricultural productivity wherever possible, but especially in the countries where food shortages exist.
Major attention concerning solution of world food shortages has centered on cereals and food legumes. Rather limited attention has been directed to the potentials of ruminant livestock in contributing to alleviating the world food shortage. Yet the immensity of this potential almost staggers the imagination. It provides us with an opportunity that we must not overlook nor fail to capitalize on.
This opportunity stems from the fact that the world population of ruminant livestock is about two-thirds the human population or about two animals for every three people. Some sixty percent of these animals are located in the developing countries. But productivity in these countries is generally quite low. This 60 percent of the livestock population produces only as much as the eight percent that are located in the United States. There are many reasons for this low level of productivity but one of the principal ones is the lack of application of appropriate production technology. Even very elementary improvements in production practices often result in considerable advance in productivity. Because ruminant livestock exist in such large numbers, rather moderate increases in average productivity would have a heavy impact on the world's total food supply. Perhaps even more important, the additional food - meat and milk - would be especially suited to man's nutritional needs, supplying well balanced proteins, energy, minerals, vitamins, and fats.
The portion of the world that is the concern of this seminar is one with large numbers of ruminant livestock, a large land mass suited principally to livestock grazing, rather low levels of animal productivity, and a rather large predicted meat shortfall by 1980. The potential impact of significant follow-through from this meeting is especially great.
The basic resource for production by ruminant livestock is forage. Even in the United States, where large quantities of grain have been fed to beef cattle, forages provide 75 percent of the feed units consumed by all beef cattle. The role of forage in the production of ruminant animals throughout the world almost certainly will increase as human demands for grain supplies increase. In countries in Africa and elsewhere, where at best only limited quantities of grain are now available for livestock, any significant increases in animal productivity probably must result from increased productivity from rangelands and other forage-producing lands; crop residues; and, in some circumstances, strategic integration of crop lands with forage-producing lands; coupled with improved livestock, livestock management, and disease control.
In Africa a dominant role must be played by more productive rangelands. Much information is available from earlier research and experience in Africa and elsewhere that could be applied to increase rangeland productivity. Many rangeland improvement practices are sufficiently well understood that they could be put into use on appropriate sites with only minimal amounts of verification. Among such practices are (1) range seeding with improved species and cultivars, (2) grazing management, involving stocking pressures and rotational or deferred grazing systems, (3) control of undesirable plant species, (4) water collection, storage, and spreading, (5) integration of range and cultivated land, and others.
But before such practices can be applied, it is necessary to understand the ecological potentials and limitations of the various rangeland sites.
This can best be derived, and perhaps can only be derived, from rangeland surveys of various types. Reports indicate that considerable survey data on African rangelands has been accumulated. This data needs to be collated, updated, and supplemented with additional critical information where necessary. From this basis, preliminary judgments could be made concerning ecological potentials of various rangeland sites throughout Africa. It also should be possible for experienced range people to determine, rather soon, which sites require particular improvement practices and which are most likely to respond to given management or improvement inputs or combinations of inputs. From such information a priority of effort can be derived. This approach should. also identify those sites requiring more detailed information before sound judgments can be made. While there exists among the countries involved great variability in rangelands, socio-economic situations, resources available for improvement, and many other factors, there also exist areas of similarity. There are a number of research centres located in the countries involved. Payoff from effort in any country will be greatest if the efforts of individual research or extension centres, national and international, are coordinated to maximize interchange of data, information, and experience.
Recent developments such as remote sensing, automated data collation, and others are powerful tools that should quickly be applied to the problem of rangeland survey and monitoring. These techniques particularly are susceptible to international cooperation in financing, use, and application.
It should not be implied that the problem of increasing rangeland and livestock productivity is a simple one that can be quickly solved. Solution will require the application of considerable amounts of resources and technical competence; the acquisition of additional survey information; research to understand better the application of management tools to the problem under a wide variety of environmental, economic, and social situations; educational efforts to create understanding of the benefits of improvement as well as the mechanics of improvement; political decisions to commit resources and to facilitate improvement; and probably many other inputs.
This seminar should provide an impetus to move forward with positive action toward solution of the problem. Hopefully, it will provide not only an exchange of information and experience on rangeland survey but also stimulate a course of action.