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In Finland, recycling of wood-ash as a fertilizer has been widely studied in recent decades in peatlands drained for forestry. Wood-ash is reported to promote tree growth without any significant negative impacts on the environment and could, therefore, be a suitable option on cut-away peatlands, which are estimated to increase by 30,000 ha over the next ten years. However, the environmental effects of ash-fertilization on cut-away peatlands or on ground vegetation are not well known. We studied the effects of wood- and peat-ash application on the nutrient content in soil and plants and on the heavy metal content in the vegetation of a cut-away peatland. Six treatments of different quantities and mixtures of wood-ash, peat-ash, biotite, or Forest PK-fertilizer were replicated in three plots. Both wood- and peat-ash fertilization ensured an adequate level of nutrients for the early establishment and growth of ground vegetation and birch seedlings in a cut-away peatland. Dense pioneer moss cover was important in trapping the heavy metals, such as cadmium, which are present in the ash. Ground vegetation of mosses and herbaceous plants also had a major role in the retention of the nutrients that could otherwise have leached from the open cut-away peatland area during the early stages of afforestation. Both wood- and peat-ash proved to be suitable for the initial fertilization of afforested cut-away peatlands, but in order to guarantee a sufficient long-term potassium supply for tree growth, an application of biotite with the peat-ash is recommended. 相似文献
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Hannu?AhokasEmail author Eila?Heikkil? Marja-Leena?Alho 《Genetic Resources and Crop Evolution》2005,52(7):813-819
The previously found wide range in the ratios of avenin or methanol-precipitated fractions to residual proteins was revisited by studying 75 oat varieties, mainly representing landraces from Finland, and included old varieties or selections, cv. Kytö, synthetic hexaploid oats and an Avena strigosa line (HA 71–87). The means of the fraction ratios ranged from 4.17 to 6.46 with significant differences. Samples of 10 narrow-ratio and 10 wide-ratio oats were compared more closely. The wide-ratio sample had significantly higher total protein content and significantly lower content of the methanol-precipitated protein fraction. Therefore, both fractions in general appear to contribute to the ratio of the protein fractions. The wide-ratio sample had significantly lower grain mass and husk-free karyopsis mass. Samples of the extreme ends in the ratios of the protein fractions showed different electrophoretic protein patterns, which was also seen in samples representing the same population of origin. It is evident that polymorphisms in the protein fractions would allow breeding of oat cultivars showing further lowering of proteins putatively toxic to coeliacs assuming oats contain these toxic proteins. 相似文献
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Mature Norway spruce (Picea abies) cones of different ages and colonized by Thekopsora areolata were collected in northern Finland 2009–2010. The germination capacity of aeciospores collected from intact aecia was measured on water agar and compared across cone age. Seed formation was investigated in healthy cones and those infected by T. areolata, Chrysomyxa pirolata, Chrysomyxa ledi, and seed germination was also measured for healthy cones and those infected by T. areolata. Unsporulated aecia of T. areolata occurred in 0- to 4-year-old cones. Aeciospores from current-year cones did not germinate and the germination capacity was significantly higher in one- to three-year-old cones than in older or current-year cones. However, a small number of aeciospores remained viable in four-year-old cones. Seed number and apparent health were significantly lower in cones infected by T. areolata and C. pirolata than in healthy cones or cones infected by C. ledi. Seed germination was significantly lower in cones infected with T. areolata compared to seeds from healthy cones. Our results suggest that infected cones more than one-year old continue to spread T. areolata for several years after the initial infection and fruiting, and thus promote the likelihood of epidemics and virulence of local outbreaks. Although cones infected by T. areolata and C. pirolata form significantly fewer seeds and of diminished viability, C. ledi does not appear to affect seed formation and health in Norway spruce. We recommend all rust-infected cones to be removed from orchards to improve stand health, reduce the risk of local outbreaks, and thereby increase the production and quality of Norway spruce seed. 相似文献
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Kivini H Järvenpää EP Aro H Huopalahti R Ryhänen EL 《Journal of agricultural and food chemistry》2004,52(13):4289-4295
Quantitative and qualitative high-performance liquid chromatographic methods were utilized to separate phospholipid classes. After qualitative separation, the fatty acid moieties of each separated phospholipid class were determined using a gas chromatographic method. On the basis of these analyses, the effect of supplemented feeds on hen egg yolk lipids can be evaluated. The supplemented feeds contained 1-5% of vegetable-based or fish oils. The phospholipid content and composition were the same in all feeding groups, the proportions of phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins being 70, 28, and 3%, respectively. In each feeding group, the fatty acid profiles of phosphatidylcholines and sphingomyelins were similar to each other and different from that of phosphatidylethanolamines. The supplemented feeds had a statistically significant (p < 0.05) effect on the fatty acid composition of phosphatidylcholines. The supplements decreased the proportion of saturated fatty acids in total fat, but this effect was not found in phospholipids. 相似文献
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Female rodents are known to terminate pregnancies after exposure to unfamiliar males ("Bruce effect"). Although laboratory support abounds, direct evidence for a Bruce effect under natural conditions is lacking. Here, we report a strong Bruce effect in a wild primate, the gelada (Theropithecus gelada). Female geladas terminate 80% of pregnancies in the weeks after a dominant male is replaced. Further, data on interbirth intervals suggest that pregnancy termination offers fitness benefits for females whose offspring would otherwise be susceptible to infanticide. Taken together, data support the hypothesis that the Bruce effect can be an adaptive strategy for females. 相似文献
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Common objectives of afforestation of cut-away peatlands are the diminution of nutrition loads and the production of energy wood in an efficient and economic way. We studied the effect of fertilization and afforestation methods on the early establishment of downy birch (Betula pubescens Ehrh.) seedlings on a cut-away peatland. Six treatments of peat-ash, wood-ash, biotite, or PK-fertilizer were replicated in three blocks in different mixtures corresponding to 50 kg/ha of phosphorous. Birch seeds were sown in randomized halves of split plots, while other halves were naturally afforested. Natural afforestation was equal to sowing in terms of seedling amounts due to closeness of surrounding birch stands with abundant seed crops. After the first growing season the greatest quantities and dominant heights of birch seedlings appeared on the ash-fertilized plots, whereas on the unfertilized areas both the establishment and growth of seedlings was very poor. On the other hand, the quantity of Scots pine (Pinus sylvestris L.) seedlings was more than three times higher on the unfertilized areas compared to the ash-fertilized areas. The differences between the fertilized and the unfertilized areas accentuated during the four observation years. Our results support regular use of ash-fertilizers for the afforestation of cut-away peatlands instead of the ash being deposited as a waste in landfills. 相似文献
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