Fertilization in northern forests – biological,economic and environmental constraints and possibilities     

Per-Ola Hedwall  Peichen Gong  Morten Ingerslev  Johan Bergh 《Scandinavian Journal of Forest Research》2014,29(4):301-311

Forests of northern ecosystems respond slowly to management activities and the possibilities to increase the growth in a short-term perspective and meet swift increases in society's demand for biomass are small. An exception among the silvicultural measures is fertilization which can be applied in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different fertilization regimens, environmental constraints and possibilities in northern forests on mineral soils. Further on we discuss the implications of both extensive and more intensive fertilization in relation to the developing bioeconomy, which encompasses the production and conversion of renewable biological resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization gives, in most cases, a small and transient effect on the environment as well as a high rate of return to the forest owner with low-economic risk. The increase in biomass production, however, is relatively small and consequently the impact on the processing industry and the bioeconomy is limited. More intensive fertilization regimens implying intensive fertilization starting in young forests may, on the other hand, considerably increase the biomass supply and value for the industry. The economic and environmental risks of this type of fertilization may, however, be larger and more research is needed on the effects on the stand level, and especially on the landscape level, including late rotation management of the forest.  相似文献   

From Microencapsulation to High Pressure Processing and from Krill to Tilapia     

Morten Sivertsvik 《Journal Of Aquatic Food Product Technology》2020,29(3)

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Wood-inhabiting macrofungi in Danish beech-forests - conflicting diversity patterns and their implications in a conservation perspective     

Jacob Heilmann-Clausen  Morten Christensen 《Biological conservation》2005,122(4):633-642

Macrofungal diversity was investigated on 281 decaying beech trees distributed across 14 forests in Denmark, based on sporocarp inventories. Two aspects of diversity were considered, i.e., species richness per fallen tree and the incidence of red-listed species occurrence per tree. For both diversity measures the effects of both tree and site variables were tested. In total, 319 fungal species were identified, including 28 red-listed. Decay stage and wood volume were identified as key variables influencing species richness as well as red-listed species incidence. Red-listed species, however, showed a preference for more decayed trees than non red-listed species. Further, red-listed species incidence was found to be significantly higher on broken trees, compared to fallen trees with a distinct root-plate, indicating tree death cause to be important for some red-listed species. The relations between diversity measures and site variables were conflicting. Species richness per tree decreased with increasing maximum tree age and dead wood continuity, possibly a consequence of competitive exclusion of unspecialised opportunistic species in old-grown stands. For red-listed species the opposite trend was evident, and it is concluded that forest history may have fundamental effects on the community structure of wood-inhabiting fungi. Accordingly, simple species richness may be a misleading conservation measure if the aim is to conserve the most threatened aspects of forest biodiversity.  相似文献   

Acute toxicity of high doses of the glycoalkaloids, alpha-solanine and alpha-chaconine, in the Syrian Golden hamster     

Langkilde S  Schrøder M  Stewart D  Meyer O  Conner S  Davies H  Poulsen M 《Journal of agricultural and food chemistry》2008,56(18):8753-8760

Sprouted, stressed, or spoiled potato tubers have reportedly led to human acute intoxication, coma, and death when consumed in high amounts. These effects have been attributed to glycoalkaloids (GAs), primarily alpha-solanine and alpha-chaconine, naturally present in all potatoes. The level of GAs in potato tubers has previously been shown to increase substantially as a result of improper handling and postharvest storage. A short-term study was performed to investigate the dose-response profile of alpha-solanine and alpha-chaconine alone or in combination, administered daily by oral gavage to Syrian Golden hamsters. Daily doses of 100 mg of alpha-solanine [kg body weight (BW)] (-1) induced death in two of four hamsters within 4 days, when administered by gavage to female Syrian hamsters. Doses of 100 mg of alpha-chaconine alone or alpha-solanine and alpha-chaconine combined in a ratio of 1:2.5, in doses of 75 or 100 mg (kg BW) (-1), induced death in one of four hamsters within the same period. Animals dosed with alpha-solanine alone or in combination with alpha-chaconine suffered from fluid-filled and dilated small intestines. The GA administration had no effect on acetyl cholinesterase (AChE) or butyryl cholinesterase (BuChE) activity in plasma or brain. Liquid chromatography-mass spectrometry-based metabolomics showed that there was a specific accumulation of alpha-chaconine in the liver tissues. In addition, metabolomics gave direct evidence of glycolytic metabolism of the GA with the beta 1, beta 2, and gamma-GAs detected in the urine and, to a lesser extent, the feces. Doses from 75 mg (kg BW) (-1) of alpha-chaconine, alpha-solanine, or the two compounds combined were potentially lethal within 4-5 days in the Syrian Golden hamster. However, the cause of death in these studies could not be established. No synergistic effects of alpha-solanine combined with alpha-chaconine were evident.  相似文献