This audiotutorial unit (cassette, printed script, 76 color slides, study guide, self-evaluation test), prepared by the Communications Support Unit at CIAT, is available for use with a manually or automatically synchronized slide projector/cassette tape reccorder. Each unit is a vailabIe from the Distribution Office at a cost of US$ 50; photocopies of the study guide alone can be obtained from the Cassava Information Center. The objective of this unit is to present some of the results of research conducted by the physiology Section of CIATs Cassava Program.

This policy brief describes work carried out by CIAT in partnership with the University of the West Indies (UWI), which used climate predictions and crop suitability models to assess the likely impact of climate change on crops grown in Trinidad & Tobago. Key policy recommendations are provided.

The results of a survey conducted in 1983 among 416 farmers participating in the integrated rural development project (DRI, Colombia) in Atlantico (60), Bolivar (66), Cordoba (156), and Sucre (134), on land use and importance of cassava within the farming system, are presented. Except for Bolivar, where cassava and yam plantings decreased, increased land use attributable to increased credit availability was observed. In general, 1.7 ha cassava was planted per farm in 1982-83, mainly in association with yam, maize, and plantains; 55 percent of the land planted included cassava.

The presentation looks at the current status of river systems of India from a basin perspective, and review how indicators of urbanization, such as demographics and migration, infrastructure development, growth of cities and towns, development of urban agglomerations, provision of utility services and land-use changes, have impacted the life of rivers.

It is widely believed that tropical soils (mainly Oxisols) have excellent physical characteristics such as high infiltration rates, high permeability of water, good and stable soil structure and that consequently, they can support mechanized agriculture. However in the Eastern Plains (Llanos Orientales) of Colombia, when Oxisols are subjected to tillage using disc harrow, soil physical conditions deteriorate rapidly.