6. Discussion
Element cycling is currently a central theme in ecosystem ecology (Ågren & Andersson 2012, Andersson
1970a). The main results of the present study are summarised in Table 8. The yearly biomass increase indicates
that at the time of measurement, the Linnebjer forest ecosystem is still in an aggradation or accumulation phase
(Bormann & Likens 1979). Tree biomass increased yearly by 6.6 t∙ha−1 or 3.1 t∙ha−1 carbon. The other elements
accumulated in the order: N > Ca > Mg > K > Mn > Si > P, in amounts ranging from 29 to 1.8 kg∙ha−1 yearly.
The litterfall returned elements to the soil. 14% - 53% was decomposed and returned to the ecosystem over the
year. It can thus be assumed that the exchangeable pool of elements was slightly increasing. The atmospheric
deposition of sulfur observed was sufficient to cause acidification of the forest soil. The nitrogen input should
have had a fertilising effect, leading to increased forest growth.
The results reported deal with plant biomass, primary production and mineral cycling. Earlier the two first
properties have been reported, but the mineral cycling not. As the results still are valid and can serve as reference
material, it is considered essential to have them published. The cycling of carbon, nitrogen and sulfur are
elements, which are affected by a changing climate and deposition. Repeated investigations make it possible to
address questions like the forest as a source or sink for carbon.
The result of plant biomass and production are less affected by time as the methods are considered as more or
less the same today. Chemical methods and techniques have changed more. The results related to chemistry and
reported are, however, considered as “robust” and will allow being used for comparisons. Even if “modern”
chemical methods are used, the final results are depending on the quality of the data from the estimation of plant
biomass and production.
In a follow up paper, results from an investigation of sampling in vegetation and soil after fifty years will be
reported.
Acknowledgements
These investigations were carried out at the former Department of Ecology, University of Lund, under the leadership
of Professor Nils Malmer. The work took place over a long period leading to a PhD degree in 1970.
Mineral cycling of the oak forest was intended to be a part of the PhD thesis, but the analysis had to be postponed
for practical reasons. A number of people assisted in the work. Laboratory assistance was provided by,
among others, Anita Balogh, Maj-Lis Gernersson and Mimmi Varga. Field assistance was provided by a ne-
6. Discussion
Element cycling is currently a central theme in ecosystem ecology (Ågren & Andersson 2012, Andersson
1970a). The main results of the present study are summarised in Table 8. The yearly biomass increase indicates
that at the time of measurement, the Linnebjer forest ecosystem is still in an aggradation or accumulation phase
(Bormann & Likens 1979). Tree biomass increased yearly by 6.6 t∙ha−1 or 3.1 t∙ha−1 carbon. The other elements
accumulated in the order: N > Ca > Mg > K > Mn > Si > P, in amounts ranging from 29 to 1.8 kg∙ha−1 yearly.
The litterfall returned elements to the soil. 14% - 53% was decomposed and returned to the ecosystem over the
year. It can thus be assumed that the exchangeable pool of elements was slightly increasing. The atmospheric
deposition of sulfur observed was sufficient to cause acidification of the forest soil. The nitrogen input should
have had a fertilising effect, leading to increased forest growth.
The results reported deal with plant biomass, primary production and mineral cycling. Earlier the two first
properties have been reported, but the mineral cycling not. As the results still are valid and can serve as reference
material, it is considered essential to have them published. The cycling of carbon, nitrogen and sulfur are
elements, which are affected by a changing climate and deposition. Repeated investigations make it possible to
address questions like the forest as a source or sink for carbon.
The result of plant biomass and production are less affected by time as the methods are considered as more or
less the same today. Chemical methods and techniques have changed more. The results related to chemistry and
reported are, however, considered as “robust” and will allow being used for comparisons. Even if “modern”
chemical methods are used, the final results are depending on the quality of the data from the estimation of plant
biomass and production.
In a follow up paper, results from an investigation of sampling in vegetation and soil after fifty years will be
reported.
Acknowledgements
These investigations were carried out at the former Department of Ecology, University of Lund, under the leadership
of Professor Nils Malmer. The work took place over a long period leading to a PhD degree in 1970.
Mineral cycling of the oak forest was intended to be a part of the PhD thesis, but the analysis had to be postponed
for practical reasons. A number of people assisted in the work. Laboratory assistance was provided by,
among others, Anita Balogh, Maj-Lis Gernersson and Mimmi Varga. Field assistance was provided by a ne-
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