Szántóföldi szénmérleg egy közép-magyarországi mintaterületen
Carbon balance of a cropland site in Middle-Hungary
., GRÜNWALD , T ., HAVRÁNKOVÁ , K ., ILVESNIEMI , H ., JANOUS , D ., KNOHL , A ., LAURILA , T ., LOHILA , A ., LOUSTAU , D ., MATTEUCCI , G ., … VALENTINI , R ., 2005 . On the separation of net ecosystem exchange into assimilation and
The carbon balance of the sandy pasture (Bugac) and the mountain meadow (Mátra) varied between −171 and 96 gC m−2 year−1, and −194 and 14 gC m−2 year−1, respectively, during the study period (2003–2009). Large part of interannual variability of net ecosystem exchange (NEE) was explained by the variation of the annual sum of precipitation in the sandy grassland ecosystem, while this relationship was weaker in the case of the mountain meadow on heavy clay soil. These different responses are largely explained by soil texture characteristics leading to differences in soil water contents available to plants at the two grasslands. The grassland on heavy clay soil was more sensitive to temporal distribution of rainfall for the same reason. The mountain meadow therefore seems to be more vulnerable to droughts, while the sandy grassland is better adapted to water shortage. The precipitation threshold (annual sum), below which the grassland turns into source of carbon dioxide on annual basis, is only 50–80 mm higher than the 10 years average precipitation sum. In extremely dry years (2003, 2007 and 2009), even the sandy grassland ecosystem was not stable enough to maintain its sink character.
exchange of carbon in a deciduous forest. Plant Cell and Environment 24. 571–583 Hanson P. J. Leaf age affects the seasonal pattern of photoresynthetic capacity and net ecosystem
77 Jaksic, V., G. Kiely, J. Albertson, R. Oren, G. Katul, P. Leahy and K. A. Byrne. 2006. Net ecosystem exchange of grassland in contrasting wet and dry years. Agricultural and Forest
Jaksic, V., G. Kiely, J. Albertson, R. Oren, G. Katul, P. Leahy and K. A. Byrne. 2006. Net ecosystem exchange of grassland in contrasting wet and dry years. Agricultural and Forest Meteorology 139:3–4: 323