Investigations on tree species suitable for the recultivation of degraded land areas in Central Amazonia.

In cooperation with the Embrapa Amazonia Ocidental in Manaus (Amazonas, Brasil) and three German projects (ENV 23, ENV 45, ENV 52), in the year 2000 we especially investigated (1) photosynthesis and carbohydrate allocation and (2) the plant-water relationships of the selected tree species. Special emphasis was given to the three species of the family Meliaceae. Comparative experiments have been done for monoculture, polycultures, enrichment cultures, and primary forests.bitstream/item/198164/1/Id-6216-todo.pdfAnnual Report 2000

Investigations on tree species suitable for the recultivation of degraded land areas in central Amazonia.

During the first phase of the project (january 1, 1995 until april 30, 1998), the influence of the water and element supply of tree different plantation systems on the growth and wood formation of eight native tree species (Swietenia macrophylla, Carapa guianensis, Cedrela odorata, Dipterex odorata, Hymenaea courbaril, Ceiba pentandra, Virola surinamensis, Tabebuia heptaphylla) was investigated. In 1998, the data were analyzed. The results subsequently served as a basis for the second phase of the project (comp. chapter 5) which should give deeper insight into the relationship between exogenous and endogenous input, the plant metabolism, and the wood formation and wood quality of plantation-grown trees. due to the results obtained in these studies in the second phase of the project, special attention is given to the subsequent species : Swietenia macrophylla, Carapa guianensis, Cedrela odorata, Dipterex odorata, and Hymenaea courbaril. Corresponding investigations are carried out in the plantation system I (monoculture system) in comparison to system III (enrichment system). Supplementary studies on the environment-tree growth relationship of Swietenia macrophylla and Carapa guianensis are carried out in a mixed culture system (system II, comp. Schmidt et al. 1999, chapter 5). For the study on wood quality and the significance of endogenous factors for wood formation experimental areas of the Instituto Nacional de Pesquisa da Amazonia ( INPA, Manaus) 45 km north of Manaus, and some trees from primary forests of the region were included in this study.bitstream/item/201400/1/Investigations-on-Tree-Species-Suitable....pdfAnnual Report 1998 Ed. by J. Bauch; O. Dünisch, L. Gasparotto; C. de Azevedo; R. de Lima; R. de Morais

How to measure the Pomeron phase in diffractive dipion photoproduction

The study of charge asymmetry of pions in the high-energy process gamma p -> pi+ pi- p (e p -> e pi+ pi- p) at very small dipion momenta offers a method to measure the phase of the forward hadronic (quasi)elastic amplitude gamma p -> rho p. We estimate potential of such measurements at HERA.Comment: 12 pages, 2 figures; v4: more elaborate parametrizations of dipion spectra implemented, discussion extende