01560naa a2200241 a 450000100080000000500110000800800410001902400410006010000170010124500910011826000090020952008990021865000130111765000110113065000230114165000190116465000170118365000260120065000160122665000090124270000180125177300490126915207972023-05-09       1978    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.2307/19365712DOI1 aSTARK, N. M.  aNutrient retention by the root mat of an Amozonian rain forest.h[electronic resource]  c1978  aAbstract: Surface root mats on oxisols and spodosols near San Carlos de Rio Negro, Venezuela, were sprayed with (45)Ca and (32)P to simulate the addition of nutrients to the soil surface through leaching of decomposing litter, and through precipitation and throughfall. Collections from lysimeters placed below the root mat and humus layer showed that in all but 1 case, &lt0.1% of the radiotracers leached past the root?organic mat, and leaching stopped completely after 1 to 2 months. Through analysis of root mat samples, the radioisotopes were found to have been taken up and translocated by living roots. This is the first evidence supporting the ability of the root map on the surface of poor, depleted tropical soils to efficiently take up dissolved nutrients before they percolate down to mineral soil. Other studies have shown up that one of the uptake mechanisms is mycorrhizal fungi.  aAmazonia  aBrazil  aNutrient retention  aSoil chemistry  aSoil physics  aTropical rain forests  aFertilidade  aSolo1 aJORDAN, C. F.  tEcologygv. 59, n. 3, p. 434-437, May, 1978.