Search results for "Picea"
showing 10 items of 113 documents
Investigations on the Polyamine Content of Spruce Needles Relative to the Occurrence of Novel Forest Decline
1991
Summary Levels of free polyamines were monitored in needles of spruce trees [ Picea abies (L.) Karst.] during the course of two vegetation periods at five natural sites. The putrescine concentration in needles of damaged spruce trees was significantly higher than in needles of undamaged trees. This is e.g. impressively proved by the putrescine/spermidine-ratio. While undamaged trees show nearly similar putrescine and spermidine concentrations, damaged trees have five- to tenfold higher putrescine levels depending on the increasing state of damage. Thus, the content of putrescine in needles can be used as a qualified biochemical damage indicator of spruce trees. The physiological effects of …
Phosphoenolpyruvate Carboxylase Activity and Malate Content of Spruce Needles of Healthy and Damaged Trees at Three Mountain Sites
1991
Summary Investigations were carried out on the phosphoenolpyruvate carboxylase (PEPC) activity and the malate content in spruce trees [Picea abies (L.) Karst] at three natural sites. In needles of damaged spruce the PEPC activity is significantly higher than in needles of undamaged spruce. Therefore, the PEPC activity seems to be a biochemical damage indicator in spruce needles. The increase in PEPC activity in damaged trees is discussed as a repair mechanism to compensate the increased need of carbon skeletons by providing oxaloacetate. The malate content is enhanced in needles of severely damaged trees. An increase in malate seems to indicate senescence reactions and may be related to the…
Investigation on phospheonol pyruvate carboxylase and proline in damaged and indamaged needles of Picea Abies and Abies Alba
1998
The client of forest damage is rapidly characterized by visible criteria such as loss and yellowing of leaves and needles Additionally damage to Norway spruce (Picea abies) and silver fit (Abies alba) can be diagnosed by biochemical criteria. The results in the present study performed in 1993 and 1994 on six Norway Spruces of each of the eleven open air stands in south-western Germany indicate that the activity of phosphoenol pyruvate carboxylase (PEPC) correlates with the extent of damage and of the loss of needles, respectively. Needles of severely damaged trees had higher levels of PEPC than needles of healthy trees. There was also a positive correlation between the activity of PEPC and …
Ethylene-biosynthesis in conifers: Investigations on the emission of ethylene and the content of ACC and MACC in Norway Spruce (Picea abies) and silv…
1998
Abstract The assessment of forest damage is carried out throughout the European Community by evaluation of the loss and yellowing of leaves or needles. The results of this ocular damage diagnosis can be confirmed and stated more precisely by applying biochemical criteria, e.g. by monitoring ethylene, its precursor ACC (1-amino-cyclopropane-carboxylate) and the malonyl conjugate of ACC malonyl-amino-cyclopropane-carboxylate (MACC). Therefore we investigated ethylene emissions well as ACC and MACC contents in six Norway Spruce trees (Picea abies) each of eleven permanently monitored sites in the southwest of Germany. The same examinations were applied with silver fir at two additional sites. …
Biochemical indicators for novel forest decline in spruce
1998
Abstract The impact of air pollution on 24 stands of spruce trees in several regions in Germany was investigated. We looked for evidence of biochemical and physiological change at the level of the photosynthetic thylakoid membranes as well as for changes in the antioxidative system in two year old needles. We observed that, as the chlorophyll content decreases in the needles, the amoung of D1 protein declines far more rapidly in relation to the redox components P700 and cytochrome f. Consequently, the PSII/PSI stoichiometry keeps dropping to pregressively lower, meaning unfavorable, values at the chlorophyll content diminishes. This is particularly the case in the higher elevation character…
Selection of biological and chemical parameters indicating or affecting the vitality of Norway spruce
1991
Abstract Thirty-two young and old Norway spruce trees ( Picea abies (L.) Karst.) showing different degrees of damage were investigated in a forest stand in the Taunus Mountains (FRG). The old trees showed visual symptoms of damage such as discolouration of the needles and needle loss. Over 70 biometric, physiological and chemical parameters were determined for needle and soil samples. Interrelationships between these variables were described by correlation analysis. The most discriminant variables between different groups of trees were found by Fisher weighing. This reduced data set was used for principal component analysis and for the classification of various parameters according to diffe…
Organic material dissolved during oxygen-alkali pulping of hot-water-extracted spruce sawdust
2016
Untreated and hot-water-extracted (HWE) Norway spruce (Picea abies) sawdust was cooked using the sulfur-free oxygen-alkali (OA) method under the following conditions: temperature, 170 °C; liquor-to-wood ratio, 5:1 L/kg; and NaOH charge, 19% on the oven-dry sawdust. In comparison with earlier studies conducted with birch sawdust, the spruce cooking yield data, together with the amount of the pulp rejects (78% to 86% for reference pulps from the initial feedstock and 73% to 83% for pulps from the HWE feedstock), revealed that the pretreatment stage prior to spruce OA pulping caused different effects on pulping performance. The analyses of the three main compound groups (i.e., lignin, volatile…
The Loss of Structural Integrity in Damaged Spruce Needles from Locations Exposed to Air Pollution I. Mesophyll and Central Cylinder
1990
In connection with the new type of forest damage, the individual disease situation of two-year-old spruce (Picea abies) needles was analyzed histopathologically in forest areas exposed to different levels of O3-, SO2- and NO3- pollution. Early damage results from losses of chlorophyll in the mesophyll cells. The bleaching is more intensive towards the apex in severely damaged needles. The cytoplasm is aggregated at the cell wall and the chloroplasts show definite structural damage as well. The mesophyll cells below the epidermis, or the cells adjacent to the vascular bundle sheath, appear to be particularly susceptible. Collapsed cells (bone cells), which increase in number with damage, can…
Oribatid mites (Acari: Oribatida) in boreal forest floor and decaying wood
2008
Summary We studied the oribatid mite communities in forest floor and in decaying wood in pine (Pinus sylvestris), spruce (Picea abies) and deciduous (mainly Betula pendula and B. pubescens) forests at different latitudes in Finland. The study sites were either in mature managed forests or in old-growth forests in nature reserves. Altogether 78 sites were sampled in 2004 and 2005, yielding a total of 38,145 oribatid mites belonging to 133 species, of which four were new to Finland. Oribatid mite communities differed in terms of total number and community structure between forest types and latitudes within the boreal forest zone. The most abundant and diverse communities were in spruce forest…
Distribution of sulphur forms in soils from beech and spruce forests of Mont Loz�re (France)
1993
From a quantitative inventory of sulphur forms and sulphur budget, the relation between the distribution of the various sulphur forms and the sulphate fluxes in three soil profiles has been addressed. These profiles are located in two forested watersheds at Mont Lozere. One has been sampled in a beech forest and the other two in a spruce forest and in a harvested plot of this spruce forest, respectively. The mean annual input-output budgets showed a sulphur immobilization in the soil cover of the three plots. In the preserved spruce forest plot, because of larger dry depositions, the sulphur immobilization is much greater than in other plots and occurs essentially in the B horizons. In the …