Nutrient-poor site

This profile becomes relevant as agricultural lands are converted. Because A Horizon soils from productive farms are valuable and nutrient-rich, land buyers usually treat them as a mineable resource for resale. Prior to construction, therefore, tractors and land moving equipment scrape the many tons of valuable soil off the surface and cart it away (consider a 100 square yard site scraped to the depth of just a few feet will produce around ten tons of soil at retail, 40-pound bags sell for 6 each). This leaves a far thinner layer of good soil near the surface. Even where intentional removal of topsoil is not conducted, construction typically leads to large-scale erosion of this valuable topsoil layer that, coupled with compaction from heavy equipment and machinery, later makes for a poor growing environment. ... 

A comparison of these data with those of an Amazonian forest shows that the aerial biomass of the trees of a cerrado sensu stricto in central Brazil may be only 8 to 22% of that of an Amazonian forest, and the basal area only 10 to 26% (Table 5.3). This difference in biomass reflects directly on the nutrient pools in the biomass. A comparison of the data reported by Klinge et al. (1995) for the aboveground biomass and nutrient stock in two inundation forests in the Ilha de Marchantaria with the data for a cerrado sensu stricto from central Brazil (Silva 1990) illustrates how nutritionally poor the cerrado is in quantitative terms. The proportions of stock of essential nutrients in the tree biomass of cerrado are 7 to 16% for P, 1.7 to 4.6% for K, 0.83 to 3.09% for Ca, and 3.5 to 7.4% for Mg. Thus Ca, K, and Mg seem to be much more deficient in the cerrados than P. We have no corresponding data for the stock of nutrients in the root biomass of trees for comparison among the two ecosystems. This comparison is only illustrative of two specific sites. Estimates of aboveground biomass for the Amazonian forests may vary... 

Scotch pine (Pinus sylvestris L.), the main forest species on sandy soils or dry sites in Europe did not escape the present decay. The reduction of needle years and needle length and sparse foliage create the impression of thin crowns and sickness. Poor sandy soils in the plains were affected most which might be due to nutrient imbalances because of high input of ammonia from increased life stock. 

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