[permaculture] A few notes on restoration ecology
Nathan Czuba
nathanaczuba at yahoo.com
Tue Oct 9 16:23:33 EDT 2007
So I was reading through a few ecology papers and found things that you all might find interesting/useful.
"Whereas native sassafras-persimmon stands are generally invaded by oaks, pines are usually invaded both by old-field species such as sassafras and by later successional oaks. In contrast, planted stands of black locust (Robinia pseudoacacia) tend to be invaded by elm (Ulmus americana), black cherry (Prunus serotina), box elder (Acer negundo), hackberry (Celtis occidentalis) and other mesic forest species (Ashby 1964).
As reported by Carmean et al. (1976), "height growth at 16 years of planted black walnut (Julgans nigra), sweetgum (Liquidambar styraciflua) and tulip tree was greatest on the part of the field clearcut from a black locust plantation, and least on the portion occupied by broomsedge (Andropogon virginicus), poverty grass (Danthonia spicata and goldenrod (Solidage spp.) at the time of planting. Heights were intermediate and approximately equal on plots clearcut from a shortleaf pine plantation and on a portion of the field fully stocked with sassafras, persimmon and elm. Planted red oak (Quercus rubra) grew best on plots clearcut from black locust and shortleaf pine, relatively poorly on the formerly fully stocked area, and, like the black walnut, did not live past ten years on the non-stocked, herbaceous area of the field. These growth results were related to foliar nitrogen levels, noncapillary soil pore volume, bulk density, and organic matter content, and to
mycorrhizal and phosphorus fertilization studies carried out in pots. Allelopathic compounds produced by broomsedge and sassafras were as considered to have influenced the growth results."
An "interesting process is the tendency of certain species to 'pump' cations, or move them from lower soil horizons to the soil surface." A study by Alban (1982) contrasted "the effect of aspen (Populus spp.) and white spruce (Picea glauca) with red pine (Pinus resinosa) and jack pine (P. banksiana) on the distribution of cations and pH in the soil. These four species were planted simultaneously on two different sites in northern Minnesota. After about 40 years of growth, both the spruce and the aspen stands have experienced a large removal of cations from the lower soil horizons. These have been incorporated into the forest floor and biomass material. The effect of this has been to create a nearly neutral forest floor at the expense of acidifying the lower horizons. The pines have had the opposite effect: the forest floor has been acidified by biological activity, while the lower horizons maintain the high initial pH. If restoration plans called for the
establishment of species requiring neutral surface soils, the use of cation pump species might be a more effect way of achieving and maintaining this condition than single or continuous application of lime."
Alban, D. H. 1982, Effects of nutrient accumulation by aspen, spruce and pine on soil properties, Soil Science Society of America Journal, 46, 853-861
Ashby, W. C. 1964, Vegetation development on a strip-mined area in southern Illinois. Transactions of the Illinois State Academy of Science, 57, 78-83
Carmean, W. H., et al. 1976, Hardwoods Planted in Old Fields Favored by Prior Tree Cover. USDA Forest Service Research Paper NC-134
---------------------------------
Pinpoint customers who are looking for what you sell.
More information about the permaculture
mailing list