Description
Riparian woods are one of the 7 environments identified in the provincial nature reserves.
The marsh and riparian woods, which until the beginning of the last century occupied vast areas of the valley bottoms of Trentino, have been practically wiped out by land reclamation and the channelling of rivers.
All that remains of these environments today are a few vestiges: thin strips surviving here and there along some watercourses, impoverished in their specific composition and degraded by human interventions. Or a few strips that almost miraculously escaped reclamation, as they are located in areas unsuitable for cultivation, such as the marshy shores of lakes or the periodically flooded areas adjoining watercourses.
| 
|
| The main type of riparian forest is that of black alder(Alnus glutinosa), which settles in marshy places or in any case with a shallow water table. Other tree species can also be found in it, such as white poplar(Populus alba), black poplar(Populus nigra), white willow(Salix alba) and white alder(Alnus incana). The white alder is decidedly less hygrophilous and therefore only occupies areas of alder woodland characterised by well-drained gravelly soils. Instead, it sometimes gives rise to its own riparian forests, the white alder alder groves, in areas that insist on alluvial fill, alongside streams or rivers. In these tree formations, the undergrowth is generally much less rich and luxuriant than in black alder alders. The marshy soils with peaty substrate are the environments in which very rare and interesting plant communities can develop: the marshy shrublands. They are mainly composed of Salix cinerea and secondarily of frangula, while the herbaceous layer is usually made up of marsh species. | |
|
|
| Riparian forests are usually environments with avery rich and interesting birdlife. The greatest variety is found where there are large trees with abundant undergrowth. In these cases, in addition to numerous species of small song sparrows, which nest among the bushes and in the foliage, larger birds such as woodpeckers or some diurnal or nocturnal birds of prey may be present. | |
|
|
| Riparian forests are not particularly favourable environments for reptiles, as their microclimate is rather cool and open places suitable for sunbathing are limited. The most common species are therefore those linked to the presence of water, particularly the natrines. | |
|
|
| In riparian forests, the presence of a high degree of humidity and the cover provided by the tree layer facilitates the presence of some species of amphibians. Frogs, toads and salamanders lay their eggs or larvae in the pools of water that frequently occupy the depressions in the ground or in the streams that flow through these woods. | |
|
|
| There are no mammal species exclusive to these environments, i.e. they find in them the only habitat for survival. There are, however, numerous species that habitually frequent riparian woods as particularly peaceful environments, often 'islands' of nature within anthropised valley floors and therefore oases of refuge, feeding and reproduction. | |
