Suchergebnisse

Central Amazonian floodplain forests are an unique and endangered ecosystem. The forests grow in areas that are annually flooded by large rivers during mean periods of up to 8 months and at depths of up to 10 m. Despite this severe stress, these forests consist of over 1,000 species and are by far the most species-rich floodplain forests worldwide. The trees show a broad range of morphological, anatomical, physiological, and phenological adaptations that enable them not only to survive the adverse environmental conditions, but also to produce large amounts of biomass when the nutrient levels in water and soils are sufficiently high. This is the case in the floodplains of white-water rivers, which are used for fisheries, agriculture, and cattle-ranching but which also have a high potential for the production of timber and non-timber products, when adequately managed. Latest research on ecophysiology gives insight how tree species adapt to the oscillating flood-pulse focusing on their photosynthesis, respiration, sap flow, biochemistry, phenology, wood and leave anatomy, root morphology and functioning, fruit chemistry, seed germination, seedling establishment, nitrogen fixation and genetic variability. Based on tree ages, lifetime growth rates and net primary production, new concepts are developed to improve the sustainability of traditional forest managements in the background of an integrated natural resource management. This is the first integrative book on the functioning and ecologically oriented use of floodplain forests in the tropics and sub-tropics.It provides fundamental knowledge for scientist, students, foresters and other professionals on their distribution, evolution and phytogeography. 'This book is an excellent testimony to the interdisciplinary collaboration of a group of very dedicated scientists to unravel the functioning of the Amazonian Floodplain forests. They have brought together a highly valuable contribution on the distribution, ecology, primary production, ecophysiology, typology, biodiversity, and human use of these forests offering recommendations for sustainable management and future projects in science and development of these unique wetland ecosystems. It lays a solid scientific foundation for wetland ecologists, foresters, environmentalists, wetland managers, and all those interested in sustainable management in the tropics and subtropics.' Brij Gopal, Executive Vice President International Society for Limnology (SIL).

In order to test the effect of the lower availability of water for vegetation in a tropical Amazonian forest, a long-term research project was created in 2001 called Projeto Seca Floresta (ESECAFLOR). The main objective of the project is to determine how a significant reduction of the available water in the soil, in the long term, can affect the biota. The ESECAFLOR consists of two 1-hectare plots, the experimental plot is covered with 6,000 plastic panels reducing precipitation by 50%. The objective of this work is to compare the floristic and plant structure (< 2 meters high) between the experimental and control of ESECAFLOR plots. There was a significant reduction in species richness and diversity, plant density and height, and a significant change in species composition between experimental plot compared to control. The plant community clearly responded to the reduction of soil moisture in the experimental plot, corroborating the results of some climate models that say rainfall reduction in the Amazon will negatively affect the plant community.