Heuck, C; Spohn, M: Carbon, nitrogen and phosphorus net mineralization in organic horizons of temperate forest: Stoichiometry and relations to organic matter quality, Biogeochemistry, 131, 229-242 (2016), doi:10.1007/s10533-016-0276-7
The rates of mineralization processes influence C sequestration and soil fertility, but despite their importance for ecosystem functioning, C, N and P net mineralization rates are seldom investigated together. Hence, we studied the relationships between net mineralization rates and organic matter stoichiometry in an 8-week incubation experiment with Oi, Oe and Oa horizon material of six beech, one spruce and one pine site. We determined C, N and P net mineralization rates, organic C quality and C:N:P stoichiometry. Net N mineralization only occurred below molar organic matter C:N ratios of 40 (Oi) or 28 (Oa) and N:P ratios of 42 (Oi) or 60 (Oa), and increased with decreasing C:N and N:P ratios. Net P mineralization only occurred below C:P ratios of 1400 (Oi) and N:P ratios of 40 (Oi), and increased with decreasing C:P and N:P ratios. Net N and P mineralization were strongly positively correlated with each other (r = 0.64, p < 0.001), whereas correlations of both net N and net P mineralization with C mineralization were weak. The average C:N:P stoichiometry of net mineralization was 620:4:1 (beech, Oi), 15,350:5:1 (coniferous, Oi), 1520:8:1 (Oe) and 2160:36:1 (Oa). On average, ratios of C:N net mineralization were higher, and ratios of N:P net mineralization lower than organic matter C:N and N:P ratios. This difference contributed to the decrease of C:N ratios and increase of N:P ratios from the Oi to the Oa horizons. In conclusion, the study shows that C, N and P net mineralization rates were closely correlated with the organic matter stoichiometry and that these correlations were modified by the degree of decomposition of the organic matter.
Aktuelle Termine

Mi. 22.11.2017 aktuell
The Roots of Drought Tolerance
Do. 23.11.2017
Death and deception: The ecology and evolution of carrion flowers
Do. 30.11.2017
Improving land models through the use of surface temperature evaluations
Ökologisch-Botanischer Garten:
So. 03.12.2017
Von Anis bis Zimt: Gewürze im Lebkuchen
Do. 07.12.2017
Ökumenische Andacht zum Advent mit dem Swahili Chor Bayreuth
Wetter Versuchsflächen
Luftdruck (356m): 968.9 hPa
Lufttemperatur: 7.7 °C
Niederschlag: 0.0 mm/24h
Sonnenschein: <1 h/d
Wind (Höhe 17m): 6.5 km/h
Wind (Max.): 16.9 km/h
Windrichtung: SW

Globalstrahlung: 222 W/m²
Lufttemperatur: 3.8 °C
Niederschlag: 0.1 mm/24h
Sonnenschein: <1 h/d
Wind (Höhe 32m): 17.4 km/h
Wind (Max.): 44.5 km/h