One of the most important studies being conducted today, at the Institute for Ecological Studies of the Carey Arboretum in Milbrook, New York is examining the types of changes to soil systems ocurring in the most urban to more natural landscapes. Scientists are monitoring the similarities and differences of oak woodlands growing on similar soils on sites extending from Central Parkk, in Manhattan to a distance of about 200 miles north of New York where the institute is located.
This ongoing study has already shown several important urban-to-rural gradients in and around the New York City area. (Mcdonnell, Picket and Pouyat 1993). Heavy metals in the soil were higher in urban areas and declined outwards. Salt in the soil and soil waters trended in the same way. Urban soils tended to be more hydrophobic, that is more resistant to wetting, as well.
Urban soils also had higher rates of mineralization of nitrogen, which is the conversion of organic forms of nitrogen, such as soil organic matter, to inorganic forms such as nitrate. The authors suggested that the principal changes brought about by nitrogen deposition may be an increase in the abundance of bacteria in the soil and litter combined with reductions in fungal and invertebrate populations. Urban forest-floor litter also decomposes more quickly than that of countryside forests. The authors further suggest that higher nitrogen deposition on the urban end of the gradient leads to the faster release of organic nitrogen from soil and litter that they observed.
Soil structure is affected by these changes, too, particularly by a shift from fungal dominance to bacterial dominance. The webby mycelia that comprise the bulk of soil's fungal component serves to knit together soil particles and bits of organic matter, while the substances secreted by bacteria are slippery and cause soil to slump when it is exposed to rain (Harris, Birch and Short 1993).
Unfortunately, conventional soil tests do not measure such factors as total biomass, that is, the living component of the soil, nor do they i
dentify levels of specific fungi or invertebrates. Conventional soils analyses do not reflect the high levels of nutrients cycling through ecosystems today because the analyses reflect what is present at the time rather than what is flowing through the system. Thus we have remarkably little information on the soil's functional character.
I have been carving my niche my way or the highway slowly and focused. The information is taken from that work of art, The Once and Future Forest, previously mentioned more than once.
Moving along, the crime committed by Alberto Areces Mallea and Gabriela Ocampo is much more grave than what I thought a decade ago. The destruction was total.
Nevertheless, their stupidity and arrogance, has kept me going to places no other islander, in the horticultural/gardening/landscape installation here, has ever dreamed off. Forest restoration, its principles can make anyjuan a better practioner. Understanding what goes down below the surface, could only improve what develops on top.
that is that
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