Carbon sequestration in short-rotation forestry plantations and in Belgian forest ecosystems

In deze studie werd nagegaan in hoeverre plantages met een korte omloopstijd en Belgische bossen kunnen bijdragen tot het bereiken van de broeikasgasemissiereductiedoelstelling die de Belgische overheid aangegaan is onder het Kyoto Protocol

Modelling short-term CO2 fluxes and long-term tree growth in temperate forests with ASPECTS

peer reviewedThe net ecosystem exchange (NEE) Of CO2 between temperate forests and the atmosphere governs both carbon removal from the atmosphere and forest growth. In recent years, many experiments have been conducted to determine temperate forest NEE. These data have been used by forest modellers to better understand the processes that govern CO, fluxes, and estimate the evolution of these fluxes under changing environmental conditions. Nevertheless, it is not clear whether models capable of handling short-term processes, which are mostly source-driven, can provide an accurate estimate of long-term forest growth, which is potentially more influenced by sink- and phenology-related processes. To analyse the interactions between short- and long-term processes, we developed the ASPECTS model, which predicts long-term forest growth by integrating, over time, hourly NEE estimates. Validation data consisting of measurements of NEE by eddy-covariance and forest carbon reservoir estimates were obtained from mixed deciduous and evergreen experimental forests located in Belgium. ASPECTS accurately estimated both: (1) the NEE fluxes for several years of data; and (2) the amount of carbon contained in stems, branches, leaves, fine and coarse roots. Our simulations demonstrated that: (1) NEE measurements in Belgian forests are compatible with forest growth over the course of the 20th century, and (2) that forest history and long-term processes need to be considered for accurate simulation of short-term CO2 fluxes

Root length and distribution in the mineral soil of a mixed deciduous forest (experimental forest Aelmoeseneie)

Root  length and root mass were studied in two different forest stands: an  oak-beech and an ash stand, both in the 'Aelmoeseneie' experimental forest at Gontrode, Belgium. In the oak-beech    stand, the length of the finest roots &amp;lt; 1 mm) was significantly higher  than the length of the other    diameter classes (1-2 and 2-5 mm) in the upper 60 cm of the mineral soil.  Because of large    variances, this significance could not be found in the ash forest. In this  ash forest type, the length    of the finest roots in the upper mineral soil layer (0-15 cm) was higher  than all the other lengths,    both considering the vertical root length distribution within the ash plot,  and comparing the ash plot    to the oak-beech stand. For the root mass, only the amount of roots with a  diameter between 2    and 5 mm in the upper mineral soil layer of the ash plot was significantly  higher than the others.    SpecifiC root length (m root/g D.M.) is calculated for both the oak-beech  and the ash plot. These    values can be used to convert biomass data into root length data, which  gives a better indication of    the water uptake capacity of the forest stand.</jats:p