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1.
During a seven-month period the effect of different nitrogen (N) availability in soil on growth and nutrient uptake was studied in three-year-old Norway spruce (Picea abies [L.] Karst.) trees. The plants were grown in pots on N-poor forest soil supplied with various amounts and forms (inorganic and organic) of N. Increasing supply of inorganic N (as NH4NO3) increased the formation of new shoots and shoot dry weight. The root/shoot dry weight ratio of new growth was drastically decreased from 1.6 in plants without N supply to 0.5 in plants supplied with high levels of NH4NO3. This decrease in root/shoot dry weight ratio was associated with distinct changes in root morphology in favour of shorter and thicker roots. The addition of keratin as organic N source did neither affect growth nor root morphology of the trees. The amount of N taken up by plants was closely related to the supply of inorganic N, and trees supplied with highest levels of NH4NO3 also had the highest N contents in the dry matter of needles and roots. In contrast, N contents in needles of trees grown without additional N, or with keratin supply, were in the deficiency range. Supply of NH4NO3 decreased the contents of phosphate (P) and potassium (K) and therefore markedly increased N/P and N/K ratios in the needles. On the other hand, the contents of calcium (Ca), magnesium (Mg), and manganese (Mn) in the needles were increased in the plants supplied with inorganic N, suggesting high soil availability and promotion of uptake of these divalent cations by high nitrate uptake. The observed effects on root/shoot dry weight ratio, root morphology, and mineral nutrient composition of the needles indicated that high inorganic N supply may increase above-ground productivity but at the same time decrease the tolerance of trees against soil-borne (e.g. deficiency of other mineral nutrients) stress factors. Deceased 21 September 1996 Deceased 21 September 1996  相似文献   

2.
Summary Nitrate reductase (EC 1.6.6.2) activity (NRA), as measured by an in vivo assay, is present in needle leaves and mycorrhizal fine root tips of adult Norway spruce [Picea abies (L.) Karst.] in at least equal amounts on a fresh weight basis, in both adult and 5-year-old trees. NRA could also be demonstrated in trunk wood of deroted trees after fertilization with 5 mM , exhibiting a longitudinal profile in the trunk. Inducibility in needles can more efficiently be achieved by NO2 (100 g·m-3) than by 5 mM nitrate, which is effective only in root-amputated trees. A remarkably high level of needle-NRA in unfertilized trees, which are characterized by a very low level of nitrate in the xylem sap, suggests that NRA in spruce needles may in part be constitutive. Organic-N is a major nitrogen source for the needles even in root-amputated trees, indicating pronounced exchange processes between ray parenchyma and trunk xylem, which in turn are modified by the nitrogen source fed to the trunk stump. Intact trees exhibit a very similar amino acid composition of the xylem sap, regardless of whether or has been fed. The amino acid pattern of the needles is not thrown out of balance by flooding with and , which occurs in fertilized derooted trees. This indicates a distinct potential for homoeostasis of nitrogen entrance-metabolism (i.e. NRA and glutamine synthetase activity) in the needles. In the ectomycorrhiza/fine root-system (EMC), marked differences in NRA were observed depending on root-tip diameter and along the longitudinal profile of the fine roots. EMC-nitrate reductase is strongly enhanced by . Needle-NRA exhibits a circannual rhythm. An early summer maximum is followed by a December minimum. This activity pattern matches well the transitory increase of soluble nitrogen in spring and the total protein maximum in winter. In an indirect way assimilatory NRA may well contribute to nitrogen overfertilization (by consumption of NOX) as one possible cause of the contemporary decline of spruce populations.  相似文献   

3.
Thirty-seven populations of Norway spruce [Picea abies (L.) Karst.] across the Austrian Alps and Bohemian Massif were sampled to elucidate the geographical pattern of genetic differentiation. Three polymorphic mitochondrial DNA (mtDNA) loci were surveyed. Two or three alleles were detected at each locus, resulting in seven multilocus mtDNA haplotypes (A–F). Western populations proved to be monomorphic, whereas eastern and central Austrian populations were slightly to highly polymorphic, respectively. As revealed by spatial analysis of molecular variance and Monmonier’s analysis, the two main haplotypes A and B are not randomly distributed. Haplotype A was restricted to central and eastern Austria, whereas haplotype B occurred in all Austrian populations but was the only haplotype identified in western populations. This pattern may be explained by different glacial refugia located in the Dinaric Alps and the Carpathian mountains.  相似文献   

4.
Mehne-Jakobs  Beate 《Plant and Soil》1995,168(1):255-261
In order to investigate the influence of different magnesium nutrition on photosynthesis, one hundred 6-year-old spruce trees derived from one clone were planted in October 1990 into a special out-door experimental construction, where they were cultivated in sand culture with an optimal supply of nutrients, except magnesium, via circulating nutrient solutions. Magnesium was added to the nutrient solutions in three different concentrations, varying from optimal to severe deficient supplies. During the first vegetative period in 1991, photosynthetic performance and carboxylation efficiency were measured under saturating light, controlled CO2 conditions, optimal temperature and humidity, using a minicuvette system.During summer, the trees under moderate magnesium deficiency developed tip yellowing symptoms on older needles, while the youngest needles remained green with unchanged chlorophyll contents. Trees under severe magnesium deficiency showed yellowing symptoms on all needle age classes combined with decreased chlorophyll contents in the youngest needles as well. In comparison with the controls, the photosynthetic performance of the 1-year-old needles was significantly lower in both deficiency treatments. The same was observed in the youngest needles of the trees under severe deficiency. Trees under moderate deficiency treatment decreased in photosynthetic performance during the summer without reduction of chlorophyll contents. The reduction of photosynthetic rates corresponded to a decrease in carboxylation efficiency, which is taken as a measure of the activity of the enzyme ribulose-1,5-bisphosphate carboxylase. This reduction, together with the observed increase of carbohydrate contents in needles of trees growing under magnesium deficiency, led to the assumption that the photosynthetic carbonfixation is reduced as a consequence of the accumulation of carbohydrates.  相似文献   

5.
Summary Relationships between root zone temperature, concentrations and uptake rates of NH 4 + and NO 3 were studied in non-mycorrhizal roots of 4-year-old Norway spruce under controlled environmental conditions. Additionally, in a forest stand NH 4 + and NO 3 uptake rates along the root axis and changes in the rhizosphere pH were measured. In the concentration (Cmin) range of 100–150 M uptake rates of NH 4 + were 3–4 times higher than those of NO 3 The preference for NH 4 + uptake was also reflected in the minimum concentration (Cmin) values. Supplying NH4NO3, the rate of NO 3 uptake was very low until the NH 4 + concentrations had fallen below about 100 M. The shift from NH 4 + to NO 3 uptake was correlated with a corresponding shift from net H+ production to net H+ consumption in the external solution. The uptake rates of NH 4 + were correlated with equimolar net production of H+. With NO 3 nutrition net consumption of H+ was approximately twice as high as uptake rates of NO 3 In the forest stand the NO 3 concentration in the soil solution was more than 10 times higher than the NH 4 + concentration (<100 M), and the rhizosphere pH of non-mycorrhizal roots considerably higher than the bulk soil pH. The rhizosphere pH increase was particularly evident in apical root zones where the rates of water and NO 3 uptake and nitrate reductase activity were also higher. The results are summarized in a model of water and nutrient transport to, and uptake by, non-mycorrhizal roots of Norway spruce in a forest stand. Model calculations indicate that delivery to the roots by mass flow may meet most of the plant demand of nitrogen and calcium, and that non-mycorrhizal root tips have the potential to take up most of the delivered nitrate and calcium.  相似文献   

6.
Localization and activity of three enzymes involved in the amino acid metabolism of ectomycorrhizas were investigated within an interdisciplinary experiment performed in a mature Norway spruce stand in Southern Germany (Höglwald). The enzymes NAD-glutamate dehydrogenase and aspartate aminotransferase were present in root cells, whereas aminopeptidase was found in mycorrhizas of Norway spruce such as Piceirhiza nigra and those with the fungi Cenococcum geophilum, Elaphomyces sp., Russula ochroleuca and Tylospora sp. Mycorrhizas growing in the humus layer contained about double the amount of protein found in those taken from the upper mineral soil (0–5 cm).Acid irrigation of the soil had no effect on the activity of any of the investigated enzymes, soluble protein or total N-contents irrespective of whether roots were taken from the organic layer or from the upper mineral soil. Liming, however, stimulated the activity of the three enzymes in mycorrhizas of the organic layer (Of+Oh) whereas it had no effect on the activity of the investigated enzymes of mycorrhizas in the upper mineral soil. This effect is attributed to increased contents of soluble organic nitrogen compounds in the soil of the limed plots as compared to the unlimed plots.  相似文献   

7.
Summary Proton-induced X-ray microanalysis (micro-PIXE) permits the simultaneous determination of the content and the distribution of elements with atomic numbers higher than Z = 13 in biological samples. This method was used to investigate element content and localization in cross-sections of 6-month-old spruce needles. It was possible to detect the elements silicon, phosphorus, sulphur, chlorine, potassium, calcium, manganese, iron and zinc in semithin (10 m) sections of the needles. The localization of the cationic elements like potassium, calcium and manganese was determined in the one-dimensional line scan mode and in the two-dimensional raster scan mode. To demonstrate the usefulness of this method for forest decline research, element content and localization were compared in needles from two trees, which differed in their degree of damage. We were able to detect differences in the amount of cations and in their distribution inside the needles.  相似文献   

8.
Concentrations and total amounts of Cd and Zn in individual annual xylem increments of 5-year-old spruce trees (Picea abies) were investigated after one growing season in contaminated soils. The plants had been potted in soils amended with different concentrations of Cd and Zn and kept in open air conditions. In the outer xylem rings formed during the treatment period lowest concentrations of Cd and Zn were found. In inner rings concentrations of both elements increased and were highest at the pith. Total amounts of both elements showed reversed distribution patterns with highest values in the outermost rings. The observed increase of total dry matter of the rings from pith towards the outer rings was stronger than the parallel increase in total element amounts in the rings. Thus, concentrations dropped in younger rings. The time of the soil contamination event cannot be inferred from element concentrations in annual rings. The results challenge the concept of monitoring historical trends in trace element pollution using analytical data of tree rings of conifers.  相似文献   

9.
Three stands ofPicea abies [L.] Karst. with different density in the Harz Mountains (Lower Saxony, Germany) were characterized at 4 microsatellite loci. An excess of homozygotes was observed in all 3 stands at 1 simple sequence repeat (SSR) locus, suggesting the presence of null alleles. To test for the segregation of a null allele, 24 openpollinated seeds (haploid megagametophytes and embryos) from apparently homozygous mother trees were analyzed. For 1 of 3 trees that could be identified as heterozygous for a null allele, no significant deviation from the expected 1∶1 segregation into marker absence (null allele) and marker presence of the second maternal allele could be observed in the haploid megagametophyte. Concordantly, the numbers of embryos heterozygous for the null allele and for the other maternal allele were not significantly different from each other. Inheritance analyses in seedlings and corresponding megagametophytes of gymnosperms were used as a direct experimental verification of microsatellite null alleles in single-tree progeny. Microsatellites with an abundance of null alleles should be discarded from further analysis because inclusion of these loci results in incorrect estimation of allele frequencies.  相似文献   

10.
The vertical niche differentiation of genera of ectomycorrhiza (ECM) was assessed in a 17-year-old Norway spruce (Picea abies [L.] Karst.) plantation on a mountainous dolomitic site (1,050 m above sea level) of the Bavarian Limestone Alps. We determined ECM anatomotypes, recorded the abundance of corresponding ECM root tips and classified them into groups of ECM exploration types, which refer to the organisation and the extent of their extramatrical mycelia. The abundance of ECM was highest in the organic soil layers, compared to the mineral soil horizon. The ordination of the ECM communities and of the exploration types revealed segregation related to soil horizon properties. While Cenococcum geophilum preferred the organic soil layers, Lactarius spp., Tomentella spp. and Craterellus tubaeformis were generally most abundant in the mineral soil horizons. Cenococcum geophilum was the predominant species, possibly based on enhanced competitiveness under the prevailing site conditions. The short-distance exploration types (e.g. C. geophilum) preferentially colonised the organic soil layer, whereas the contact types (e.g. most of the Tomentella spp., C. tubaeformis) together with medium-distance types (e.g. Amphinema byssoides) were primarily associated with the underlying A-horizons. Therefore, the soil horizons had an important effect on the distribution of ECM and on their community structure. The spatial niche differentiation of ECM genera and exploration types is discussed in regard to specific physico-chemical properties of soil horizon and the assumed ecophysiological strategies of ECM.  相似文献   

11.
Inhibition of photosynthesis was followed during autumn and early winter in current-year sun and shade needles of unfertilized and fertilized Norway spruce [Picea abies (L.) Karst.] by simultaneous measurements of photosynthetic O2 evolution and chlorophyll a fluorescence at 20 °C. The CO2-saturated rate of O2 evolution was generally higher in sun needles of fertilized trees than in those of unfertilized trees over a wide range of incident photon flux densities (PFDs). Furthermore, the maximum photo-chemical efficiency of photosystem (PS) II, as indicated by the ratio of variable to maximum fluorescence (FV/FM) was generally higher for sun needles of fertilized trees. The depression of fv/fm during frost periods was more pronounced in sun needles than in shade needles, indicating that winter inhibition in Norway spruce is strongly light-dependent. However, the inhibition of the rate of O2 evolution at high PFDs in needles of fertilized trees during early winter was partly independent of the light regime experienced by those needles in the field, which appeared to result in a pronounced decrease in the proportion of oxidized PS II reaction centres in shade needles. A nearly identical linear relationship between the quantum yield of PS II electron transport determined by chlorophyll fluorescence and the quantum yield of O2 evolution (gross rate of O2 evolution/PFD) was obtained for the investigated types of needles during autumn and early winter. Except for shade needles of fertilized trees, this appeared to be largely achieved by adjustments in thermal energy dissipation within PS II.  相似文献   

12.
A field lysimeter study was established with the aim of investigating the effect of nitrogen availability upon drought strain in Norway spruce trees. Forest soil (Typic Udipsamment) was filled in lysimeters 1 m in diameter and 1 m deep. Small trees of Norway spruce from five different clones were planted in the lysimeters. Roofs under the canopy of the trees ensured full control of water and nutrient input. Three levels of nitrogen were given to the trees during five years; ambient rainwater, and five and fifteen times this N concentration, respectively. Additional N was given as NH4NO3 in irrigation water. Mean annual N-addition during the five years corresponded to 5, 27 and 82 kg per ha and year for the three treatments, respectively. During the third and fifth growth season drought was artificially induced. In addition to a watered control, two levels of drought were applied, representing water deprivation for 2 and 3 months, respectively, in 1990 and 3 and 4 months, respectively in 1992. A higher water consumption in the nitrogen fertilized trees during the droughts resulted in a significantly lower pre-dawn shoot water potential compared to the trees receiving ambient rain N. The interaction between drought and nitrogen fertilization was clear also for photosynthesis and transpiration. A decrease in height- and diameter increment caused by drought was most pronounced in the 82 kg N ha–1 yr–1 treatment. A water strain integral showed a strong positive correlation to the needle biomass of the trees. Foliar concentrations of several nutrients decreased significantly with increasing drought strain in the trees. Concentration of potassium and boron were especially low and visual symptoms of deficiency occurred.  相似文献   

13.
Summary In order to study physiological strain caused by release cutting, suppressed Norway spruce on mesic and moist sites was completely released from overstory birch, or 500 birches per hectare were left as a shelter. The treatments were conducted in late June in 1988 and in 1989. The spruce's reaction to the environmental change was monitored by measurements of fast chlorophyll fluorescence kinetics and analysis of chlorophyll content. This was done before treatment, 1 week after treatment, 2 months after treatment, and twice during the following growth period. Complete release resulted in a more pronounced decrease in the ratio of variable fluorescence to maximal fluorescence (Fv/Fm) than partial release. There was also a tendency for the build-up of chlorophyll content in needles to be more affected when the spruce was completely released. Released spruces on moist sites tended to be more affected by the release than released spruces on mesic sites. The results suggest that in this kind of stand the risk of damage to the spruces is greatest when the spruces are completely released on moist sites. Furthermore, it is shown that the weather conditions prevailing shortly before and after the release have a large influence on the spruce's reaction to the release. The results also indicate some adjustment to the new environment in mature needles.  相似文献   

14.
Summary Photosynthetic performance of several needle age classes of Norway spruce trees [Picea abies (L.) Karst.] in highly SO2-polluted and heavily damaged forest sites was measured at two different locations in the Ore Mountains (Erzgebirge, Krusne Hory) during early summer. The carboxylation efficiency showed a dramatic drop from current-year's needles to 1-year-old needles with only a slight further decrease with increased needle age. The light use efficiency also revealed these characteristics. For both parameters, no linear decrease with needle age could be found. In contrast, the maximum photosynthetic capacity (A2500) decreased linearly with time and revealed a good correlation with the total sulfur content of the needles. Absolute values measured for A2500 were approximately 50% lower than those of comparable trees in the nearby Fichtelgebirge. Mineral deficiencies or acute nutrient imbalances of the needles were not detected. In contrast to the situation in the forests of the Fichtelgebirge, a direct effect of gaseous SO2 on the trees in the Ore Mountains seems plausible.This paper is dedicated to our teacher Professor Otto Ludwig Lange on the occasion of his 65th birthday  相似文献   

15.
The concentrations of Ca, Sr, Ba and Mn were determined in up to five successive needle age classes from 54 individual Norway spruce trees [Picea abies (L.) Karst] from nine different sites. The accumulation behaviour was found to be very nonuniform, going from an increase with needle age to a decrease; irregular patterns were also found. The type of accumulation is largely site specific. The increasing behaviour can in most cases be approximated by a simple arithmetic function. All four elements usually show the same accumulation pattern, the similarities being closest between Ca and Mn and least between Ca and Ba. It is postulated that the similarity between the four elements is due to their precipitation and storage as oxalates. The similarity between Ca, Sr and Ba is observed at all concentrations, that with Mn only at concentrations larger than 300 g/g. Mn at small concentrations (< 50 g/g) shows a decreasing pattern and no similarity at all with Ca, Sr and Ba, but behaves similar to mobile elements.  相似文献   

16.
Summary In a 3-year study of ectomycorrhizal diversity in 2 Norway spruce stands in Switzerland the macroscopically classified ectomycorrhizal types were analyzed microscopically to compare the results of the 2 approaches. A total of 22 ectomycorrhizal types were macroscopically classified in the 2 stands. Microscopic investigations — particularly of mantle structures — resulted in the identification of 7 additional types to give a total of 29. These additional types resulted from separation of macroscopically identical types occurring on both stands (type-pairs) at the microscopic level. The problematic nature of characterization and classification of ectomycorrhizas is discussed.  相似文献   

17.
Summary Dark respiration and photosynthetic carbon dioxide refixation in purple and green Picea abies cones were investigated from budbreak to cone maturity. The rate of dark respiration per unit dry weight and CO2 refixation capacity decreased during cone maturation. At the beginning of the growing season, photosynthetic CO2 refixation could reduce the amount of CO2 released by respiration in green and purple cones by 50% and 40%, respectively. The seasonal performance of the components of the cone carbon balance was calculated using information on the seasonal course of respiration, refixation capacity and the light response curves of cone photosynthesis, as well as the actual light and temperature regime in the field. The daily gain of CO2 refixation reached 28%–34% of respiration in green and 22%–26% in purple cones during the first month of their growth, but decreased later in the season. Over the entire growth period refixation reduced carbon costs of cone production in both cone colour polymorphs by 16%–17%.  相似文献   

18.
In Europe, spruce grows in two main regions which meet in Poland, one to the north and east, the other to the south and west. The northeastern area ranges from the northern treeline extending from Norway to Siberia, to southern Sweden, north-eastern Poland and the southern Ural mountains. The southwestern spruce region reaches the mountainous areas of the Alps and the Balkans, the mountains and uplands of the Sudety Mountains, the Carpathians and neighbouring lowlands. Opinions about the distribution of Norway spruce have changed over the years, and its scarcity in the centre of Poland has been strongly debated. The favoured current theory is that Norway spruce once had a continuous distribution in Poland. It is assumed that the rare occurrence in the central Polish lowland is due to a combination of unfavourable soil conditions and previous management activity. The main aim of this work was to analyse climate–growth relationships of Norway spruce in eastern Poland and distinguish regions with similar increment patterns with regards to spruce range. Spruce growth in northern Polish sites is positively correlated with rainfall from May to July. Tree-ring widths in southern sites are more correlated with March temperature. Selected homogenous regions are the same as range types. Trees from the so-called “spruceless area” seem to have similar climate–growth relationships to trees from the southern region. This finding does not settle the question of the origin of the trees, but it does indicate that similar environmental conditions exist in these two areas and proves that the climate was not a limiting factor there.
Marcin KoprowskiEmail:
  相似文献   

19.
In situ water relations of a large subalpine Norway spruce (Picea abies) were analyzed by simultaneous measurements of sap flow at different crown positions. In the diurnal scale, transpiration varied greatly, both spatially and temporally. Over longer periods, however, different parts of the crown transpired in fairly constant proportions. The average estimated transpiration was about 3.5 times greater in the upper than in the lower half and decreased 1.6-fold from south to north. Water intercepted from rain, fog and dew buffered and significantly decreased the transpiration. The effect was strongest in those parts which were least coupled to the free atmosphere. The top of the crown seemed to experience a regular shortage of water shortly after starting transpiration, when it was forced to switch from internal reserves to sources in the soil. Further, lower branches then started transpiring, which may have led them to compete for the water. An enhanced nocturnal sap flow during warm and dry winds (Foehn) indicated that the tree also transpired at night. Shaded twigs had more capacity to intercept water externally than twigs in the sun. The significance of the crown structure for interaction with water in both liquid and vapour phases is discussed.  相似文献   

20.
Norway spruce bore an abundance of cones in Finland in 2000, but these cones were often fungal-infected. The seeds had structural injuries that were revealed when seed samples were examined using light (LM) and a field emission scanning electron microscope (FESEM). Two main types of spores were found either in the tissues inside the seed coat or on the sarcotesta, the outermost layer of seed coat. The spores of Chrysomyxa pirolata appeared particularly in the nucellar tissue, where the cell walls were disintegrated at the middle lamellae and cytoplasm was disrupted. Degenerated remnants of fungal structures resembling aecial peridium were found close to aeciospores. The tissue of the megagametophyte differed also from that of a normal mature seed. Conidia of Thysanophora penicillioides were often encountered on the sarcotesta where the ordinary wax cover was missing. Fungal injury occurred in the nucellar layers that shelter the embryo and megagametophyte from desiccation and oxidation. Destruction of these structures together with rapid opening of the seed coat advance deterioration of seeds during storage and may cause unexpected economic losses in forest plant production.  相似文献   

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