ABSTRACT
Most developing countries are characterized by a great diversity of microclimates. In most cases an approximate water balance measurement at each rainfall station is many times more useful than precise evaluations at only those locations having complete climatic data. Although other factors are believed to be more limiting on crop growth and production, yield frequently increases linearly with increasing radiation, leveling off at some value that depends upon crop, climate, soil fertility, and perhaps other conditions. A linear or curvalinear response has been measured for sugar cane, beans, rice, and other crops. Land reform programs have given too little attention to available resources, including climate. Large cattle ranches have been expropriated and turned over to settlers to produce corn and beans, only to learn after successive crop failures that precipitation was inadequate for rainfed agriculture. Since climate is variable, and frequently so over short distances, considerable caution is required in preparation of maps showing agro-ecological zones and crop suitability zones.
