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Management of Pacific Northwest riparian forests is necessary because many of these forests have been dramatically changed from their original makeup. The primary interest in riparian forest and aquatic ecosystems under the Northwest Forest Plan (NWFP) is the need to restore stream habitat for fish populations, particularly ''Anadromous salmonids''. Some of these forests have been grazed by cattle or other livestock. The heavy hooves of these animals compact the soil. This compaction doesn’t allow the water to be absorbed into the ground, so the water runs off into the stream carrying top soil along the way. The simplification of the stream itself has also had negative effects. The large woody debris in the streams has been removed to allow for easy access to the stream and for better travel in the streams themselves. But the faster moving current erodes the stream banks filling the stream with more sediment. The removal of trees on the stream banks also leads to erosion and stream degradation. Another effect of the removal of trees is an increase in stream temperatures because the lack of shade. These changes to riparian forests can be fixed through three steps; # Creation of riparian reserves # Restoration of channel complexity # Silviculture practices These steps will help restore riparian forest ecosystems which will directly help the salmon populations. == Riparian forest restoration == The following steps used to help restore and maintain healthy riparian forests came from the Bureau of Land Management’s best management practices (BMPs) in the Roseburg District. The first step towards riparian forest restoration should be the establishment of riparian reserves. The second step is to restore channel complexity. The third step is to apply silvicultural treatments to restore large conifers. The large conifer species would be western red cedar Thuja plicata and western hemlock Tsuga heterophylla. These three steps will help direct the ecosystem back to its pre-disturbed state. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Management of Pacific Northwest riparian forests」の詳細全文を読む スポンサード リンク
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