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1.
Soil Analytical Diagnosis of K- and Mg-Deficiency in Spruce Stands (Picea abies Karst.) Significant correlations were demonstrated between the amounts of exchangeable K, Mg, Ca and Al in the soil and the corresponding amounts in the needles of 44 spruce stands in southwestern Germany. Strong correlation was also found between the exchangeable Mg in the soil and the degree of yellowing of older needles. The critical levels of nutrient elements in the soil were derived from the respective contents found in the needles. Acute Mg deficiency occurs at a level of 2 μeq/g soil material. For an evaluation of the Mg nutrition of Picea abies soil analysis can replace the needle analysis. For K a similar clear definition of the deficiency range is not possible, though for K contents < 2 μeq/g soil material a deficiency is probable. However, a K deficiency can also occur at higher levels (2–5 μeq/g soil material). The soil analysis can only be regarded as a guideline indicating K deficiencies.  相似文献   

2.
Leaching of nutrients out of young intact spruce (Picea abies) by acid fog The effect of acid fog on the leaching of minerals and carbohydrates out of needles of five year old spruce trees (Picea abies) was studied. The fogs were prepared from H2SO4 and HNO3 (2:1) with a pH of 2.75 (acid treatment) and 5 (control treatment). The acid fog leached significantly higher amounts of K, Ca, Mg, Mn, and Zn as well as carbohydrates as compared with the control fog. The absolute quantities of minerals leached, however, were low and amounted to only some percent of the minerals generally present in needles. Except Zn, of which the quantity leached was about as high as the Zn needle content. Nevertheless the Zn concentration in the needles treated with acid fog was not lower than the Zn concentration in the control needles suggesting that the lost Zn was quickly compensated by Zn uptake. In the treatments with acid fog damage symptoms appeared at the end of the experimental period. In the older needles a weak chlorosis occurred; from the needles of the 1st year some turned redish brown. In the acid fog treatments all needles lacked brightness while the control needles looked bright. These symptoms were similar to those under field conditions of older spruce trees with the ?lametta syndrom”?. Electron microscopic investigation revealed that the wax layer of the needles treated with acid fog was badly damaged.  相似文献   

3.
The 6000 ha of Armand Pine in the Wushan mountainous area East of Sichuang Province in southwestern China, have almost declined completely. The preliminary investigation in the area shows that the needle chlorosis (yellowing) of Armand Pine is a common symptom of forest decline in the mountainous region, and a significant increase of the symptom has been seen in the past decade.The SO2 and rain pH data were collected from three monitoring sites in the area.Soil and needle analysis were carried out.The preliminary results indicate that yellowing was evident at all sites of lower soil pH and that soil nutrient status of Mg deficiencies were most notable on acid soils with base saturations at 3.2 to 7.5%. Magnesium, K, Zn (particularly Mg) contents of current needles were all deficient.Exchangeable Mg in the soil of the heavily damaged forest stand was lower than that of the well-growing forest. But the degree of yellowing does not rise along with the increase of A1 concentration. The preliminary investigation in the southwest indicates that the forest damage is associated with nutritional disturbances and the existence of Mg deficiency is reported as the most predominant agent in causing symptoms of yellowing foliage.  相似文献   

4.
Nutrient status in Pinus radiata sites in the Basque Country (Spain) have been established. Current-year, 1-year-old needles, and soil samples were collected in 7 sites. Needle samples were analyzed for calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P) and nitrogen (N). Soil samples were analyzed for pH (H2O), N, P, Ca, Mg, K and aluminium (Al). The results indicate differences between sites and needles of different ages. In general, nutrient concentrations in needles are sufficient for the nutritive requirements, but some low concentrations of Mg and P found in 1-year-old needles, indicate that some trees may show signs of deficiency in the near future. In turn, N concentrations are, in many cases, higher than those usually found in this species and may originate growth disorders. These concentrations may be related to NO3 ? and NH4 + deposition. Soil nutrients are sufficient for trees requirements, but the levels of K and Mg are low. Soil pH values are not very acid, and the value of the Ca/Al ratio is, in general, near 1. An arrangement of sites and physiographical and nutritional parameters based on correlation and principal component analysis is also presented.  相似文献   

5.
Aluminium toxicity as a consequence of increasing soil acidity is discussed as a primary factor in forest decline in middle Europe. Ecologically relevant concentrations of Al disturbed root systems of hydroponically grown spruce (Picea abies Karst.) seedlings. The needles, with a much lower Al content in comparison to the roots, were also affected by Al at these external concentrations. In this investigation needle chlorosis as the visible symptom of Al toxicity, was accompanied by decreasing pigment concentrations and photosynthetic rates as well as increasing starch levels and transpiration rates. The magnesium concentrations of roots and needles were lowered by treatment with Al. By feeding the needles directly with Mg, it was possible to differentiate between direct and indirect effects of Al on needle metabolism. Magnesium deficiency was found to drive all the experimental variables except transpiration.  相似文献   

6.
Japanese fir (Abies firma) forests on the urban-facing side ofMt. Oyama, eastern Japan are frequently exposed to acidic depositions. These forests have been declining more severely than those on the mountain-facing side. Chlorophyll, N, Mg, K, Ca, P and Al contents were determined for current, one- and two-year-old needles collected from the crown surfaces of Japanese fir tree forming the forest canopy (ca. 30 m height) on both sides of Mt. Oyama. Needle dry mass per needle area on the urban-facing side was significantly smaller than that on the mountain-facing sides for each needle age class. This result suggests that the development of internal tissues of fir needles on the urban-facing side is defective. N and Chl contents per needle area on the urban-facing side were smaller than those on the mountain-facing sides, indicating that photosynthetic activity per needle area is suppressed in the needles from the urban-facing side. For each needle age class, both area- and mass-based Mg contents were smaller on the urban-facing side than on the mountain-facing side, but mass-based Al contents were greater on the urban-facing side. These results suggest that acidic depositions cause nutritional disorders, which, in turn, leads to decreased needle productivity in the fir trees on the urban-facing side.  相似文献   

7.
“New type” forest damages have been observed in West Germany since the mid-1970's and discussed in North America since the early 1980's. Various types of damage are associated with typical foliar discoloration symptoms related to site characteristic nutritional disturbances. The macronutrients are generally Mg, Ca, and K. Based on foliar and soil analysis results diagnostic fertilization trials were established at a wide variety of sites and stands in West Germany as well as in North America. The appropriate application of fast soluble fertilizers proved that damage symptoms associated with nutritional disturbances can frequently be mitigated within a relatively short period. The observed visual revitalization corresponds well with foliar analysis data obtained continuously for the last 5 yr. Soil analyses also reflect the improved nutrient supply. Investigations of older fertilizer trials indicated that stands fertilized before the appearance of “new type” damage symptoms are considerably more vital when compared to the untreated control plots. Remarkable results were derived from histological research. Microscopic analysis of needles proved the regeneration potential on a histological level for moderately yellowed needles after fertilization. Furthermore, needles of nutrient deficient trees reveal typical differences of tissue damages when compared to SO2 fumigated or O3 impacted needles. Thus, histological investigations can be used as a diagnostic tool to differentiate between direct and indirect forest damages.  相似文献   

8.
Summary Microbial biomass in the upper 7 cm of soil and needle decomposition on the forest floor were measured seasonally for 10 months in a mountain hemlock (Tsuga mertensiana) old-growth forest and in a regrowth forest after Phellinus weirii, a root-rot pathogen infection, had caused disturbance. The microbial biomass was higher in the old-growth forest soil than in the regrowth forest soil. However, T. mertensiana needle decomposition rates were higher in the regrowth than in the old-growth forest. Total N, Ca, Fe, Cu, and Zn concentrations in needles increased during the 1st year of decomposition in both the old and the regrowth forests, but P, K, Mg, Mn, and B concentrations decreased. N, P, K, Mg, Cu, and Zn concentrations were lower in regrowth than in old-growth decomposing needles. During mineralization, needles in the regrowth forests released more N, P, and K as a result of higher needle decomposition rates. Our results suggest that higher needle decomposition rates increased the mineralization of N, P, and K, which may lead to increased soil fertility and faster tree growth rates in the regrowth forest.  相似文献   

9.
The concentrations of 21 elements were determined in 1 yr old needles of Norway spruce (Picea abies) at 39 different sites: The following soil parameters were measured at 3 different depths: pH, loss on ignition, total and EDTA-extractable concentrations of 28 elements. Needle concentrations were tested for correlations with soil parameters. The following significant correlations were found with pH: Al, Co, Cs, Mn, and Rb in needles increased with decreasing soil pH, whereas Ba and Sr decreased. Needle concentrations of As, Ca, Cu, Fe, K, La, Mg, P, Sb, Sc, V, and Zn had no significant correlations with soil pH. AI and Ba in needles correlated also with A1 and Ba extracted from the soil. Needle concentrations of the pairs Co and Mn, Cs and Rb, and Ba and Sr showed significant positive interelement correlations, whereas concentrations of P and K had negative interelement correlations with Mn.  相似文献   

10.
Abstract

Concentrations of N, P, K, Ca, Mg, and Mn were determined in one‐, two‐, and five‐year‐old needles from upper and lower crowns of declining and healthy red spruce (Picea rubens Sarg.) to assess nutritional deficiencies as causes of severe defoliation in upper‐elevation forests in western Massachusetts. Concentrations of N and K did not differ between stands or positions in crowns but decreased with leaf age. In declining stands, mean Ca concentrations were the same in the upper and lower crowns (3.2 mg g‐1), whereas in healthy stands, Ca was higher in the lower crown (4.8 mg g‐1) than in the upper crown (3.9 mg g‐1). Five‐year‐old needles of healthy trees had higher Ca than those of declining trees (6.0 and 3.8 mg g‐1, respectively). Mean concentrations of P and Mg in declining trees were 0.9 and 0.5 mg g‐1, respectively, with each element being at threshold levels of sufficiency. Mean concentrations of P and Mg, respectively, were 0.3 mg g‐1 and 0.2 mg g‐1 lower in needles of declining trees than in healthy trees. Five‐year‐old needles of declining trees were lower in P and Mg than those from healthy trees. Mean Mn concentrations were lower in needles of declining trees than in healthy trees (0.4 vs 1.3 mg g‐1). The results suggest that low P, Mg, and possibly Ca concentrations in needles of declining trees may contribute to the decline.  相似文献   

11.
The effects of clinker dust and wood ash on Norway spruce and Scots pine seedlings were compared in buried pots. Clinker dust (0.5 kg m?2) and wood ash (0.5 kg m?2) were applied to the surface of a nutrient-poor mineral soil. In the second year, the increase in soil pH by the dust and ash were larger than in the first year. Both alkaline treatments caused a large increase in the needle potassium (K) concentration. An excess of soil K relative to magnesium (Mg) was observed by decreased Mg concentration in needles shortly after treatment. However, Mg concentration in needles stayed in the sufficiency range. Current results confirmed earlier findings that despite a positive effect on base cation nutrition, wood ash has a low potential for increasing the biomass of forest stands on mineral soils due to the N limitation in these soils.  相似文献   

12.
Two-year-old Norway spruce (Picea abies (L.) Karst) seedlings were exposed to trafficemissions along roadsides with three different trafficdensities and speed limits; highway, street and aquiet local road. Deposition of the polyaromatichydrocarbons (PAH) was determined at all sites usingmoss bags as an indicator of organic traffic pollutantdeposition. Short term concentrations of atmosphericnitrogen oxides (NOx) and aerosol black carbon(BC) were also recorded from the sites. The responsesof the needle epicuticular wax structure of theexposed spruce seedlings were analysed under thescanning electron microscopy (SEM). The epistomatalwax structure of needles was distinctively fused andaggregated along the highway and street withrelatively high traffic densities. Along the localroad, where the traffic density was low, nosignificant degradation of needle epicuticular wax wasobserved. The NOx and BC data, along with PAHsaccumulated in moss bags indicate significantdeposition of gaseous pollutants and particulateorganic compounds along the highway and street andthese are suggested as cause of the epicuticular waxdegradation. Epistomatal wax structure is thus suggested to be an early indicator of traffic exposure effects.  相似文献   

13.
Annual terrestrial inventories carried out in West Germany since 1984 indicate that for the last 4 yr approximately 50% of the forests were damaged. The damages were and are commonly attributed to the adverse effects of acid rain and other air pollutants. As most decline types are associated with nutritional disturbances, it was found that the application of lime and/or fertilizers could reduce or even remove the damages. Therefore, the West German government has established a nationwide program by which up to 80% of the costs of fertilization in forests revealing ”new type“ forest damages are subsidized. In practice, a clear distinction is made between compensative and ameliorative fertilization methods. Compensative fertilization means the application of Mg containing lime (generally 3,000 kg-ha?1) to neutralize further acidic deposition in forest soils. The ameliorative fertilization is focused on the specific application of nutrients, particularly in stands with acute nutritional deficiencies. This is accomplished by means of readily soluble Mg and K fertilizers at application rates of 500 to 1,000 kg-ha?1. In cases of insufficient P supply or for the activation of microbial decomposer chains in organic top soil horizons, P fertilizers are utilized. For ameliorative fertilization, foliar and soil analyses are recommended as a sound basis for fertilizer selection. In many cases, particularly in the States of Bavaria and Baden-Wuerttemberg, Mg containing lime in combination with fast soluble Mg and/or K (P) fertilizers are applied. Between 1984 and 1987, approximately 400,000 ha of “new type” forest damage areas have been limed and/or fertilized in West Germany. As positive as the application of lime and/or fertilizers appear to be, there exists some potential risks and limitations of these practices with regard to restabilization and revitalization of declining forest stands.  相似文献   

14.
Many studies have dealt with the links between nutrient supply and tree growth. High N availability usually leads to increased growth but it may also be a stress factor and may affect the ability of the tree to take up both water and nutrients. We measured the nutritional status of the trees and estimated their tolerance to drought by examining the flushing of new shoots and needle loss. The studies were carried out on trees grown under different N and water supply in a field experiment using a 25–30 year old Norway spruce (Picea abies) in SW Sweden. The treatments included in this study were ammonium sulphate (NS) where 100 kg N ha?1 was applied yearly, N-free fertiliser (V) where P, K, Ca, Mg and S but no N was applied, and also the combinations of ammonium sulphate and drought (ND) and N-free fertiliser and drought (VD). The NS treatment caused increased N but decreasing P/N, K/N and Mg/N ratios in the needles whereas the N-free fertiliser resulted in increased P/N and Ca/N ratios. In ND and VD, nutrient ratios remained relatively unchanged compared with NS and V. Thus, trees keep a stable internal nutrient balance. However, as a response to the drought, ND seemed to stop the flushing of new shoots to a higher degree than VD. In conclusion, this study showed that nutrient status did affect drought resistance which could be seen as differences in the flushing of new shoots rather than changes in nutrient ratios in the needles.  相似文献   

15.
At three sites in northern Germany (Witzenhausen, Egge-Mountains and Hamburg-Eißendorf) biochemical stress bioindicators (chlorophyll, starch, proline and acid phosphatase and peroxidase activity) were determined in the needles of healthy and damaged Norway spruce (Picea abies L. Karst.). Peroxidase activity was higher in 1 and 2 yr old needles of damaged Norway spruce at the Witzenhausen and Hamburg-Eißendorf sites. Phosphatase activity was significantly higher in needles of damaged trees in all needle ages at the Egge-mountains site in 1983, and at the Witzenhausen site in current and 1 yr old needles. At the Hamburg-Eißendorf site lower phosphatase activity in needles of damaged trees was determined. At the Witzenhausen site lower levels of chlorophyll were determined in the 1 and 2 yr old needles of damaged trees, whereas at the Hamburg-Eißendorf and Egge-mountains sites lower chlorophyll levels were found in current needles. Thus between healthy and damaged trees at a specific site differences in the stress bioindicators could be found, however no common pattern between the sites could be determined. The study indicates that these biochemical bioindicators may be used to show a general stress, but it is difficult to relate them to a specific stress factor.  相似文献   

16.
The elemental concentrations of K, Rb and Cs were determined in needles from individual spruce trees as a function of the needle age class. The concentrations are highest in current year's needles and decrease smoothly in older needles, approaching a constant value. Rb and Cs show similar behaviour, whereas that of K differs in so far as its relative decrease with time is less pronounced. Intra- and intersite variation of the needle concentrations are largest for Cs and smallest for K. Individual trees show a highly significant correlation between the log (Cs) and log (Rb) values. Total soil concentrations were determined at 9 sites with different parent material. Intra- and intersite variations of K are comparable for soils and for needles, whereas those for Rb and Cs are much smaller for soils than for needles. All three elements are correlated in soil samples. There is no close connection between soil and needle concentrations at the various sites. However, the results suggest that needle concentrations of Rb and Cs, but not of K, are strongly dependent on the sorption properties of the associated soils.  相似文献   

17.
Element mass balance estimates for South Carolina Coastal Plain watersheds indicate that fertilizers and liming materials are the major sources for inputs of Ca, Mg, K, Cl, and HCO3 whereas precipitation is the major input for Na and SO4. Stream flow is the chief mode of output for all of these elements. A balance between input and output is evident only for Cl. Retentions of 50% or more are shown by Ca, Mg, K, HCO3 and SO4 whereas Na shows an apparent net loss. The retention of Ca, Mg and HCO3 suggests that less than 25% of the dolomitic liming materials applied to the landscape actually dissolve and that the carbonate chemistry of Lower Coastal Plain streams is therefore probably largely controlled by seepage of groundwaters from underlying calcareous aquifers. The retention of K and the loss of Na may be due to cation exchange reactions on soil clays whereas the apparent retention of SO4 is probably due to reduction to H2S in floodplain environments and soil adsorption.  相似文献   

18.
Microbial biomass C and N, and activities related to C and N cycles, were compared in needle and leaf litter, and in the uppermost 10 cm of soil under the litter layer in Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L.) and silver birch (Betula pendula L.) stands, planted on originally similar field afforestation sites 23–24 years ago. The ground vegetation was differentiated under different tree species, consisting of grasses and herbs under birch and pine, and mosses or no vegetation with a thick layer of needles under spruce. The C:N ratio of the soils was 13–21 and the soil pHCaCl 2 3.8–5.2. Both showed little variation under different tree species. Microbial biomass C and N, C mineralization, net ammonification, reduction) did not differ significantly in soil under different tree species either. Birch leaf litter had a higher pHCaCl 2 (5.9) than spruce and pine needle litter (pH 5.0 and 4.8, respectively). The C:N ratio of spruce needles was 30, and was considerably higher in pine needles (69) and birch leaves (54). Birch leaves tended to have the highest microbial biomass C and C mineralization. Spruce needles appeared to have the highest microbial biomass N and net formation of mineral N, whereas formation of mineral N in pine needles and birch leaves was negligible. Microbial biomass C and N were of the same order of magnitude in the soil and litter samples but C mineralization was tenfold higher in the litter samples.  相似文献   

19.
In the early summer of 1987 an untimely needle loss was observed in Scots pine (Pinus sylvestris L.) of different ages growing on oliogotrophic mineral soils in Cladina and Calluna-type heath forests in northern Finland. The first symptoms were observed at the beginning of July when current shoot growth was ending and the young needles were flushing. The older needles first yellowed then later turned brown before falling. Needle loss proceeded from the oldest to the younger needle age classes. The trees lost between one and four age classes of needles from earlier growth and retained only the most recent 1 to 3 yr needles. Foliar analysis indicated nutrient stress as revealed by retranslocation of mobile nutrients such as N and insufficient uptake of immobile nutrients such as Ca. The soil nutrient concentration, however, was normal at poor sites and therefore it appears the primary reason for needle Loss is a nutrient stress due to root damage. This damage was caused by unusual weather in the winter of 1986 to 1987, rather than by soluble Al.  相似文献   

20.
In the early summer of 1987 an untimely needle loss was observed in Scots pine (Pinus sylvestris L.) of different ages growing on oliogotrophic mineral soils in Cladina and Calluna-type heath forests in northern Finland. The first symptoms were observed at the beginning of July when current shoot growth was ending and the young needles were flushing. The older needles first yellowed then later turned brown before falling. Needle loss proceeded from the oldest to the younger needle age classes. The trees lost between one and four age classes of needles from earlier growth and retained only the most recent 1 to 3 yr needles. Foliar analysis indicated nutrient stress as revealed by retranslocation of mobile nutrients such as N and insufficient uptake of immobile nutrients such as Ca. The soil nutrient concentration, however, was normal at poor sites and therefore it appears the primary reason for needle loss is a nutrient stress due to root damage. This damage was caused by unusual weather in the winter of 1986 to 1987, rather than by soluble Al.  相似文献   

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