/ In southern Bahia, Brazil, the traditional cocoa agroecosystem with a dense shade canopy of native trees is now recognized as a secondary conservation route for highly endangered Atlantic Rainforest species. This "chocolate forest" of the densely shaded farms persists despite a massive 20-year Brazilian government modernization program in which shade was seen as a chief impediment to raising cocoa production. The objective of this study was to determine how this traditional agroecosystem endured. Although dense shade limits cocoa yield, it provides several agroecological benefits: control of insect pests and weeds, microclimate stability, and soil fertility maintenance. A keycomponent of modernization efforts was a shade-tree removal program designed to maximize cocoa production by using low shade and fertilizer while substituting agrochemicals for many beneficial roles of the overhead trees. This research found that many farmers rejected, or only partially accepted, the shade reduction process although it promised much higher cocoa yield and profit. Farmers employing a wide range of shading were interviewed, and it was found that decisions to remove or maintain the shade trees were linked to both agroecological and risk-minimization factors. Farmers' perceptions of the agroecological functions of the shade trees and individual willingness to entertain the economic risk associated with substituting agrochemicals for these were important. A less-profitable, but lower-risk approach of occasional fertilizer and agrochemical use with the traditional shade intact was a rational and widespread choice. Policies designed to maintain the traditional agroecosystem through the current economic crisis should heed the multiple functions of the overhead trees. KEY WORDS: Conservation; Brazil; Atlantic Rainforest; Cocoa; Agroecology; Risk; Agroforestry

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Salinity is widely recognized as a dominant environmental variable in estuarine systems. However, drawing clear causal relationships between salinity and estuarine floral or faunal patterns of abundance, population status, or vigor is often confounded by the great spatial and temporal variation exhibited by salinity. Averages, or other statistics, over monthly, seasonal, or longer periods are often used, but may fail to capture patterns of ecological significance. This study introduces a novel approach to characterize estuarine salinity based on deriving events of specific magnitude and duration from a long-term record; events that are also amenable to analysis of the frequency that they reoccur. With sufficient point data for salinity over the spatial domain of an estuary, these variables can be mapped and contoured to reveal spatial patterns of potential ecological significance. Model-predicted salinity for a large estuary system of the Texas coast was used to develop and test these new techniques. While this system has great variation in salinity, both temporally and spatially, we find that this variability can be characterized into well-defined and reoccurring salinity-based events. Furthermore, the frequency of reoccurrence of those events over a long-term record reveals patterns not captured by more common techniques such as averaging over similar time frames. These novel techniques provide an integrated spatial-temporal approach to salinity pattern portrayal which may be useful for examining short-term (daily-monthly) estuary processes and longer-term (yearly-decadal) limits to estuary species distributions and habitat composition.