Evidence for temperature limitation of nitrogen mineralisation in the Drakensberg Alpine Centre

Autor: Clinton Carbutt, Richard W.S. Fynn, Richard P. Beckett, Trevor J. Edwards
Rok vydání: 2013
Předmět:
Zdroj: South African Journal of Botany. 88:447-454
ISSN: 0254-6299
DOI: 10.1016/j.sajb.2013.09.001
Popis: We made use of pot experiments and soil mineralisation assays to test the effect of temperature on the soil nitrogen (N) economy of the Drakensberg Alpine Centre (‘mountain site’). The approach was enhanced by the inclusion of a contrasting warm, subtropical environment on the east coast of southern Africa (‘coast site’) which presented an opportunity to test plant growth in mountain soil outside of the mountain site's natural climatic envelope. This study was further augmented by two greenhouse experiments that helped isolate the factors responsible for the growth responses in the experiments above. Plant morphology, plant nutrients and soil nutrients were used as the basis for comparing treatment effects. The primary pot experiment showed that plant growth was uniform in the mountain site regardless of whether the test species was grown in intrinsically N-rich mountain soil or intrinsically N-poor coast soil. However, we noted significant growth differences at the coast site using the aforementioned soil nutrient regimes. In terms of the soil mineralisation assay, coast soil, derived from intrinsically N-poor sandstone, predictably mineralised little soil inorganic N at the mean spring temperature of 19°C. However against expectations, the intrinsically N-rich mountain soil mineralised
Databáze: OpenAIRE
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