Long-term trends of phosphorus nutrition and topsoil phosphorus stocks in unfertilized and fertilized Scots pine (Pinus sylvestris) stands at two sites in Southern Germany

摘要: Abstract For two Scots pine ( Pinus sylvestris ) ecosystems in S Germany with different atmospheric N deposition Pfaffenwinkel , intermediate deposition; Pustert large deposition), the supply phosphorus (P) has been monitored for unfertilized and fertilized plots over more than four decades by foliar analysis (1964–2007). Additionally, topsoil concentrations stocks of total P plant-available (citric-acid-extractable phosphate) were quantified 10-year intervals (1982/1984, 1994, 2004). At both sites, fertilization experiments, including variants control, NPKMgCa + lime, PKMgCa + lime + introduction lupine, corresponding to an addition 75 90 kg ha −1 Pfaffenwinkel, respectively had established 1964. Our study revealed trends nutritional status pines at sites during recent decades: elevated together small pools resulted significant deterioration nutrition increasingly unbalanced N/P nutrition. a trend improved from 1964 1991 was replaced opposite most 15 years. our which are characterized acidic soils thick O layers, forest floor stock citric-acid-extractable phosphate showed strong correlation concentration current-year foliage, thus appropriate variable predict stands. Total as well or mineral poorly correlated inappropriate predictors 1960s sustainably increased relative control even 40 years after fertilization; Pustert, about 20