自然保护与休闲部保护·守护·共享
自然保护与休闲部
Due to the expected impact of the winter storm, all Virginia State Park overnight facilities will be closed from Friday, Jan. 23 through Tuesday, Jan. 27. This decision is based on the forecast for unsafe conditions and potential power outages. For updates click here.
目录山麓/山地小溪冲积森林
该组中的森林占据了小溪沿岸暂时被洪水淹没的栖息地，那里有非常小规模的独特冲积地貌（例如堤坝、阶地、后沼泽）。这些群落分布在皮埃蒙特和山区山谷的许多溪流和最小的河流沿岸；山区相对高坡度的小河和大溪流沿岸的森林以前被认为是一个独特的群体（“山地冲积森林”），但现在已被合并到更广泛的范围中。土壤、洪水状况和植物组成多种多样。栖息地通常由狭窄的洪泛平原组成，有细到粗的冲积土；山中和山脚下通常有巨石或鹅卵石冲积层和岩石河床。
Characteristic trees in the Piedmont and mountain valleys include sycamore (Platanus occidentalis), eastern boxelder (Acer negundo var. negundo), American elm (Ulmus americana), green ash (Fraxinus pennsylvanica), river birch (Betula nigra), red maple (Acer rubrum), yellow buckeye (Aesculus flava; southwestern Virginia only), black walnut (Juglans nigra), tulip-tree (Liriodendron tulipifera), and black willow (Salix nigra). Shrubs include spicebush (Lindera benzoin var. benzoin), black haw (Viburnum prunifolium), American hornbeam (Carpinus caroliniana), and American hazelnut (Corylus americana). Herbaceous composition varies greatly with site conditions and geography, but generally includes such characteristic species as mistflower (Conoclinium coelestinum), hollow joe-pye weed (Eutrochium fistulosum), thin-leaved sunflower (Helianthus decapetalus), cardinal flower (Lobelia cardinalis), great blue lobelia (Lobelia siphilitica), American bugleweed (Lycopus americanus), Virginia bugleweed (Lycopus virginicus), fringed loosestrife (Steironema ciliatum), sensitive fern (Onoclea sensibilis var. sensibilis), fall phlox (Phlox paniculata), hispid hedge-nettle (Stachys hispida), tall meadow-rue (Thalictrum pubescens), and wingstem (Verbesina alternifolia) .
Along montane floodplains, most of the lower, streamside terraces are probably flooded briefly at least annually. More powerful, catastrophic floods occur at irregular intervals and may be very destructive to stream channels and vegetation. The forests of these habitats are characterized by a mixture of bottomland and mesophytic species. Among the most common trees are sycamore (Platanus occidentalis), eastern hemlock (Tsuga canadensis), eastern white pine (Pinus strobus), white oak (Quercus alba), birches (Betula alleghaniensis and Betula lenta var. lenta), and tulip-tree (Liriodendron tulipifera). Other trees that may be locally important are American beech (Fagus grandifolia), yellow buckeye (Aesculus flava), red maple (Acer rubrum), American elm (Ulmus americana) and, in far southwestern Virginia only, sweetgum (Liquidambar styraciflua). Understory shrubs may include American hornbeam (Carpinus caroliniana), great rhododendron (Rhododendron maximum), smooth alder (Alnus serrulata), willows (Salix sericea and Salix nigra), and witch hazel (Hamamelis virginiana var. virginiana). Montane floodplain habitats are relatively well drained and support a great variety of mostly mesophytic herbaceous species such as hog-peanut (Amphicarpaea bracteata), common jack-in-the-pulpit (Arisaema triphyllum ssp. triphyllum), green-and-gold (Chrysogonum virginianum var. virginianum), and golden ragwort (Packera aurea). More frequently flooded and hydric microhabitats along the stream channels, however, usually support some wetland species, e.g., twisted sedge (Carex torta), nodding sedge (Carex gynandra), fowl mannagrass (Glyceria striata var. striata), hooked buttercup (Ranunculus recurvatus var. recurvatus), and marsh blue violet (Viola cucullata).
与山麓/山地洪泛平原森林相比，该群落占据的洪泛平原较小、地形更加多样化，植被多样性较低。在弗吉尼亚州，这些森林的记录很少，而且由于过去大规模的清理、放牧、灾难性的洪水和入侵的杂草，它们大多处于退化的状况。参考文献：Coulling ( 1999 )、Fleming ( 2002 a)、Fleming ( 2007 )、Fleming 和 Coulling ( 2001 )、Fleming 和 Moorhead ( 2000 )、Gemborys ( 1974 )、Hupp ( 1982 )、Hupp ( 1986 )、Olson 和 Hupp ( 1986 )、Rawinski等人( 1994 )、Rawinski等人。（ 1996 ）。
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下载下面列出的每个社区类型的组成汇总统计电子表格。
