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In this study, generic composition of food and foraging preferences of the European beaver were determined on sites where the beavers were reintroduced after more than 200 years of absence. Research area was located on lowland (Silesian Lowland) and highland habitats (Bystrzyckie Mountains, Wałbrzyskie Mountains) in western Poland. During the study period, 17,418 trees and shrubs growing within the feeding area of the beavers were marked, out of which 4,669 were found to be cut by beavers. The results showed that the foraging preferences of beavers depend on the availability and diversity of the local food sources. In the lowlands beavers preferred the following species of trees and shrubs as their primary food source: Salix cinerea, S. fragilis, S. caprea, Cornus sanguinea and Populus tremula. In the highlands, beavers preferred Corylus avellana, Sorbus aucuparia, and Fagus sylvatica due to the low availability of Salix and Populus species. Moreover, in the highlands, beavers had to cover longer distances to reach the feeding sites and had to cut trees with larger diameter than in the lowlands.
The input of rain water to the forest floor and the composition of rainfall and throughfall water were monitored between October 2001 and September 2002 in a natural and two plantation (Eucalyptus globulus and Cupressus lusitanica) forests at Munesa, southeastern highlands of Ethiopia. The proportions of throughfall to annual incident rainfall that passed through the different forest canopies were 53% under Cupressus and the natural forest and 82% under Eucalyptus. Annual nutrients deposition by rainfall varied from 0.08 kg ha-1 yr-1 for Mg to 3.79 kg ha-1 yr-1 for Na. Wash-off of materials deposited on the canopy surface and leaching of intracellular solutes from the canopy resulted in an enrichment of throughfall fluxes in K, Mg, Ca and Cl relative to rainfall and varied among forest types, being highest under natural and Eucalyptus forests and lowest under Cupressus. Sodium, NO3–N, NH4–N, SO4–S and PO4–P fluxes in throughfall were depleted relative to rainfall, but the magnitude of net depletion was different for the different elements; highest for Na (3.87 kg ha-1 yr-1) followed by NH4–N (2.85 kg ha-1 yr-1) and lowest for PO4–P (0.42 kg ha-1 yr-1). The amount of canopy uptake and leaching were generally low in the dry season and increased sharply towards the wet season.
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