Competitiveness of mechanized tree planting in Finland

Economic pressures and labor shortage are forcing forest owners to minimize silvicultural costs and manage their forests more intensively to enhance wood production and profitability. The need to improve the cost-efficiency of tree planting is spurring its mechanization. The cost-competitiveness and time consumption of mechanized tree planting in Finland were compared to manual planting (MP) in spot mounds formed with a mounding blade and with a continuously advancing spot mounder. The results suggest that mechanized planting must increase its current productivity by 25% and 100% in order to compete with spot mounding or continuously advancing mounder followed by MP, respectively. However, in the hands of skilled operators in optimal conditions, machines can be cost-effective. On average, mechanized planting required 20% less time than MP and excavator-based spot mounding, whereas MP and continuously advancing spot mounder required 30% less time. Effective use of modern machines requires a careful evaluation of the worksite and skilled operators applying optimal operational models.     

A microcosmos study on the effects of cd-containing wood ash on the coniferous humus fungal community and the cd bioavailability

Background and Aims

The use of wood ash in forestry has been questioned because the cadmium (Cd) concentration of ash, which varies between 1 and 20 mg kg^-1 ash, exceeds the level allowed for fertilizers (3 mg kg^-1) used in agriculture. To investigate the effects of Cd and ash on the fungal community composition and Cd bioavailability of the humus layer of boreal, coniferous forests, pumice or wood ash, spiked with a water soluble (CdCl₂) or insoluble (CdO) form of Cd at three levels (0, 400 and 1000 mg kg^-1), were applied at a fertilization level of 5000 kg ha^-1 in a laboratory microcosm study.

Methods

After 2 months, the humus in the microcosms was sampled and extracted for total DNA to detect changes in the fungal community by using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. PCR was performed using the fungal 18S rDNA primers FR1 + FF390 and FR1 + NS1. The bioavailability of Cd was measured with a bacterial biosensor(Bacillus subtilis BR 151/pT0024) emitting light in the presence of Cd.

Results

Using the primer pairs FR1 + FF390 and FR1 + NS1, resulted in over 35 and 15 DGGE bands, respectively. Both primer pairs detected an ash, but no Cd effect. When using FR1 + FF390, a higher fluorescence was observed in one DGGE band of all ashed samples compared to the pumiced samples. With the primer pair FR1 + NS1, the ashed samples had a DGGE band which was not visible or only faintly visible in the pumiced samples. In addition, one DGGE band disappeared from the ashed samples. Humus layer water extracts showed that the Cd added with the pumice was in a bioavailable form. The luminescence intensity of the biosensor was dependent on the form and level of the Cd added. No luminescence was detected when the Cd was added with the ash.

Conclusions

Ash fertilization altered the humus layer fungal community, whereas the level and form of additional Cd in the ash had no influence because it was not bioavailable.     

Application of comprehensive two-dimensional liquid chromatography to elucidate the native carotenoid composition in red orange essential oil

In the present work, the ability of a LC x LC-DAD/APCI-MS method developed at this laboratory to identify the native composition of carotenoid in an extremely complex matrix such as red orange essential oil was demonstrated. To carry out this task, two independent and orthogonal separation mechanisms were coupled through a 10-port switching valve that simultaneously collected the eluent from a microbore cyano column used as the first dimension in normal phase mode and injected it to a conventional reversed phase monolithic C(18) column in the second dimension separation. By using this novel analytical technique together with the use of DAD and APCI-MS detectors it was possible to identify in the sample, without the need of any pretreatment, 40 different carotenoids. Among them, 16 carotenoid monoesters were identified, mainly beta-cryptoxanthin palmitate (C(16:0)), myristate (C(14:0)), and laureate (C(12:0)) as well as several lutein, violaxanthin, antheraxanthin, and luteoxanthin monoesters. Moreover, 21 carotenoid diesters composed by several antheraxanthin, luteoxanthin, violaxanthin, and auroxanthin diesters were found in the native carotenoid composition of the orange oil. The main carotenoid diesters were the laureate palmitate (C(12:0), C(16:0)), myristate palmitate (C(14:0), C(16:0)), and dipalmitate (C(16:0), C(16:0)) diesters, although other diesters were also identified. Besides, two different free carotenes, zeta-carotene and phytofluene, and a xanthophyll, lutein, were also determined. To the authors' knowledge, this is the first time that carotenoid diesters are described and identified in orange essential oil. Likewise, it has been demonstrated that the LC x LC approach proposed in this study is capable of coping with the direct analysis and identification of a complex natural source of carotenoids such as the orange.