Retranslocament de nutrients en les fulles senescents de faig (Fagus sylvatica L.)

Nutrient (P. K. Ca and Mg) contents of leaves prior to senescence, nutrient return in leaf litterfall, and nutrient lcaching in throughfall were measured during October and November in a beech forest experimental plot in the Montseny Mountains (NE Spain). Only K was leached in significant amounts. Rctranslocation of P and K amounted to 46% and 13%. respectively. of the foliar nutrient contents before senescence. Calcium accumulated in the leaves during this period. while Mg showed no net retranslocation or accumulation. Retranslocated P can supply a large fraction of the annual P requirements of the trees. and contributes to keep a tight P cycle. However. the percentagc of P retranslocated in this forest lies in the lower range of literature values for forest ecosystems.Es mesuraren les mineralomasses foliars de P, K, Ca i Mg abans de la senescencia i el retorn de nutrients per la caiguda de fulles i per la lixiviació en el trascol durant octubre i novembre en una parcel4a experimental de la fageda de Santa Fe (Montseny, Barcelona). Només el K es lixivia en quantitats significatives. El retranslocament de P i K representi, respectivament, el 46% i el 13% de la mineralomassa foliar abans de la senescbncia. Les fulles acumularen Ca durant aquest període. mentre que el Mg no manifesta retranslocament ni acumulació nets. La quantitat de P retranslocada (1.4 kg ha-') pot subministrar una part important dels requeriments anuals de P del faig, i contribueix a mantenir un cicle tancat de P. No obstant, el percentatge de P retranslocat en aquest bosc es dels més baixos dels trobats a la bibliografia sobre ecosistemes forestals

Retranslocament de nutrients en les fulles senescents de faig (Fagus sylvatica L.)

Nutrient (P. K. Ca and Mg) contents of leaves prior to senescence, nutrient return in leaf litterfall, and nutrient lcaching in throughfall were measured during October and November in a beech forest experimental plot in the Montseny Mountains (NE Spain). Only K was leached in significant amounts. Rctranslocation of P and K amounted to 46% and 13%. respectively. of the foliar nutrient contents before senescence. Calcium accumulated in the leaves during this period. while Mg showed no net retranslocation or accumulation. Retranslocated P can supply a large fraction of the annual P requirements of the trees. and contributes to keep a tight P cycle. However. the percentagc of P retranslocated in this forest lies in the lower range of literature values for forest ecosystems.Es mesuraren les mineralomasses foliars de P, K, Ca i Mg abans de la senescencia i el retorn de nutrients per la caiguda de fulles i per la lixiviació en el trascol durant octubre i novembre en una parcel4a experimental de la fageda de Santa Fe (Montseny, Barcelona). Només el K es lixivia en quantitats significatives. El retranslocament de P i K representi, respectivament, el 46% i el 13% de la mineralomassa foliar abans de la senescbncia. Les fulles acumularen Ca durant aquest període. mentre que el Mg no manifesta retranslocament ni acumulació nets. La quantitat de P retranslocada (1.4 kg ha-') pot subministrar una part important dels requeriments anuals de P del faig, i contribueix a mantenir un cicle tancat de P. No obstant, el percentatge de P retranslocat en aquest bosc es dels més baixos dels trobats a la bibliografia sobre ecosistemes forestals

KM3NeT: Technical design report.

KM3NeT is a deep‐sea multidisciplinary observatory in the Mediterranean Sea that will provide innovative science opportunities spanning Astroparticle Physics and Earth and Sea Science. This is possible through the synergy created by the use of a common infrastructure allowing for long term continuous operation of a neutrino telescope and marine instrumentation. The present KM3NeT Design Study concludes with this Technical Design Report which develops the ideas put forward in the Conceptual Design Report published in April 2008