Our ability to restore tropical ecosystems and to construct sustainable, useful analogs of tropical forests depends on our ability to grow communities of plants that are ecologically compatible. This research will evaluate mixtures of species likely to use space and soil resources in complementary ways, enabling them to take good advantage of the high potential productivity of the humid tropics while protecting the soil. Plants of three life forms (those that are self.supporting and have broad, horizontally displayed leaves; those that are self . J H.supporting, with narrow, erect or arching leaves; and vines) and three life spans (several months to many decades) will be grown in combinations of one, two, or three species at the La Selva Biological Station in Costa Rica. The performance of the gardens will be evaluated by measuring growth, light capture, water use, and nutrient retention. The efficiency with which simple and complex communities use resources is likely to improve dramatically during the first two years of growth, and longer.lived plants are likely to excel as community age increases. Because invasions by unwanted species are so important to the maintenance of native biodiversity, each artificial community will be tested for resistance to invasion by native and exotic plants.
