|
|
|
|
|
| Regina, Kristiina; Simojoki, Asko; Alakukku, Laura; Silvennoinen, Hanna; Dörsch, Peter; Keller, Thomas. |
| Compaction occasionally increased N2O in soil air. No large differences in soil air composition, N2O emissions or moisture content were found between the treatments. The N2O concentrations at 15, 30, 50 and 70 cm depths correlated positively with the emission of N2O from the soil in both fields (r=0.4-0.7***). The subsoil O2 concentrations correlated negatively with N2O emission, but only at the Finnish site. The results suggest that subsoil compaction does not significantly increase N2O emissions from these soils 15-30 years after compaction. This may indicate a minor role of subsoil in the production of N2O compared with topsoil. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Soil. |
| Ano: 2011 |
URL: http://orgprints.org/19576/1/Regina.pdf |
| |
|
|
| Simojoki, Asko; Fazekas-Becker, Orsolya; Horn, Rainer. |
| Intensification of mechanical agriculture has increased the risk for soil compaction and deformation. Simultaneously, reduced tillage practices have become popular due to energy saving and environmental concerns, as they may strengthen and improve the functioning of structured soil pore system. Soil aeration is affected by both compaction and reduced tillage through changes in soil structure and in the distribution of easily decomposable organic matter. We investigated whether a single wheeling by a 35 000 kg sugar-beet harvester in a Stagnic Luvisol derived from loess near Göttingen, Germany, influenced the gas transport properties (air permeability, gaseous macro- and microdiffusivities, oxygen diffusion rate) in the topsoil and subsoil samples, and... |
| Tipo: Journal paper |
Palavras-chave: Soil. |
| Ano: 2008 |
URL: http://orgprints.org/16895/1/simojoki.pdf |
| |
|
|
| Simojoki, Asko; Xue, Tailin; Lukkari, Kaarina; Pennanen, Arja; Hartikainen, Helinä. |
| Allocation of selenium (Se) in lettuce and its impact on root morphology were studied to better understand the growth responses of plants to added Se. Lettuce was grown in vermiculite under controlled growing conditions for seven weeks, and the allocation in the shoots and roots of selenate added in increasing dosages (0, 1, 10, 100, 500 and 1000 µg Se per 3.5-litre pot) as well as morphological variables of the roots were determined. The intermediate additions of 100 and 500 µg Se per pot seemed to produce the highest biomasses, although this was nearly masked by large scatter in the data. The Se contents both in roots and shoots increased roughly proportionally to the amount of Se added. However, at small additions Se was preferentially allocated to... |
| Tipo: Journal paper |
Palavras-chave: Crop husbandry. |
| Ano: 2003 |
URL: http://orgprints.org/16746/1/simojoki.pdf |
| |
|
|
|
