Relationships between symptoms expressed by Norway spruce and foliar and soil elemental status

Surveys conducted from 1987 to 1990 of Norway spruce [Picea abies(L.) Karst.] within 12 plantations across 4 northeastern states revealed symptoms of crown discoloration and defoliation on a site-specific basis. Foliar N. K. and Ca concentrations of most of the sampled trees were above deficiency ranges, while foliar Mg concentrations of most of the symptomatic trees were below the deficiency range within the plantations. Soil pH, exchangeable Mg, K, Ca, and their corresponding percent saturations in soils were lower, while soil Al concentrations were higher for most of the symptomatic trees in comparison to the healthy trees. Foliar concentrations of Mg, Ca, K, P, Al, Mn, Pb, and Zn were positively correlated with concentrations of corresponding soil elements. Knowledge of nutrient deficiency ranges may help diagnose foliar symptoms, but their exclusive use may overly simplify relationships between foliar symptoms and foliar elements. Principal component regression analysis of the data provided assessment of interactions and balances among foliar elements, and among soil elements and their possible influences on crown symptoms. Crown symptoms were not only associated with concentrations of individual elements of foliage and soils, but also associated with interactions and balances between these elements. The influences of individual soil elements on discoloration and defoliation may depend upon other elements in soils. Soil Al may induce crown discoloration and defoliation by interfering with Mg, Ca, and K uptake in acidic soils.     

Crown Condition and Nutrient Status of Red Spruce (Picea Rubens Sarg.) in West Virginia

The appearance, foliar nutrient status, and soil nutrient availability were determined for 9 trees in each of 39 red spruce stands in West Viginia. Visual evaluation of crown conditions for all 351 trees sampled resulted in median values of 5% for discoloration and 10% for defoliation. The most common symptom of discoloration was needle chlorosis, found on the upper surface of collected branches. Defoliation generally occurred beginning with the older year-classes of needles and progressed outward toward the branch tips. The levels of discoloration and defoliation varied to such an extent among stands, plots, and trees within a plot that a single causal agent was not likely responsible for the observed symptoms. Foliar nutrient levels were compared to observed crown condition but were inconclusive in proving a definite relationship between crown condition and any individual nutrient; levels of foliar N and P were negatively correlated to defoliation, but not to discoloration or live crown ratio; yet, foliar K was negatively correlated to both discoloration and defoliation and positively correlated to live crown ration. While individual sample trees exhibited symptoms of reduced health and vigor, the majority of red spruce sampled during the course of this study appeared healthy.     

Nutrient response to diagnostic fertilization of Norway spruce Picea aries (L.) karst plantations in Western Quebec,Canada

Maple forests in southern Quebec are suffering in the 1980s from a serious decline thought to be associated, in part, with acid deposition effects on their nutrient status. Research was undertaken to determine if conifers were subject to similar phenomena. The nutrient status of three Norway spruce plantations in southwestern Quebec were studied through foliar and soil analyses. In all locations low N and K and marginal Mg foliar concentrations were identified. Diagnostic fertilization resulted in improved K and P and in some cases Mg and N levels. The foliage of the treated trees has an improved dark green color as compared with the controls. From this research it is evident that nutrient deficiencies of N, K and Mg, in particular, are showing up in spruce stands in the areas where air pollution and acid rain are relatively severe. Proper diagnostic fertilization helped to correct the nutrient disturbances.     

Correction of magnesium deficiency in a young stand of Norway spruce

A trial testing of the effect of several types of Mg fertilizer was established in a 9 yr old plantation of Norway spruce at the Col du Donon in the Vosgian mountains (France). The plantation, which had exhibited symptoms of Mg deficiency (yellowing), had been fertilized 5 yr prior to this study with 40 kg ha^–1 of Mg applied as Epsom-salts. This alleviated the deficiency symptoms, but the yellowing reappeared 3 yr after the fertilization and increased until the year in which the second fertilization trial (described in this paper) was established. Five Mg fertilizers (2 forms of slag, 2 forms of limestone, and Epsom-salts) at two rates of Mg (40 and 80 kg ha^–1) were compared to a control. Just after this second fertilization, the trees became green again and small positive effects on circumference and basal area increments has been observed. However, 12 yr after the treatment, there were no differences between the treatments regarding needle coloration, circumference, basal area or volume.     

Correction of magnesium deficiency in a young stand of Norway spruce

A trial testing of the effect of several types of Mg fertilizer was established in a 9 yr old plantation of Norway spruce at the Col du Donon in the Vosgian mountains (France). The plantation, which had exhibited symptoms of Mg deficiency (yellowing), had been fertilized 5 yr prior to this study with 40 kg ha⁻¹ of Mg applied as Epsom-salts. This alleviated the deficiency symptoms, but the yellowing reappeared 3 yr after the fertilization and increased until the year in which the second fertilization trial (described in this paper) was established. Five Mg fertilizers (2 forms of slag, 2 forms of limestone, and Epsom-salts) at two rates of Mg (40 and 80 kg ha⁻¹) were compared to a control. Just after this second fertilization, the trees became green again and small positive effects on circumference and basal area increments has been observed. However, 12 yr after the treatment, there were no differences between the treatments regarding needle coloration, circumference, basal area or volume.     

Magnesium- und Calcium-Ernährung von Hochlagenfichten —Vergilbungszustand und Reaktion auf unterschiedliche Düngung

Magnesium and calcium nutrition of spruce on high altitude sites — yellowing status and effects of fertilizer application On the ARINUS experimental sites in the Schwarzwald (SW Germany) since 1987 the mineral nutrition of Norway spruce was investigated using various experimental fertilizer treatments. The studies were focused on the nutrient Mg as acute Mg deficiency symptoms were observed at the beginning of the experiments. Treatments with ammonium sulfate, kieserite and dolomitic limestone were carried out to achieve an experimental modification of the Mg supply. In this paper, results on yellowing status, long-term foliar analysis, and data on the binding forms of Mg and Ca in the needles are presented. By application of Mg containing fertilizers the Mg nutrition of the trees could be markedly improved. Thus, deficiency symptoms disappeared. Kieserite application resulted in the fastest response of foliar Mg concentrations. In contrast to Mg, Ca deficiency could not be observed. The results of the (NH₄)₂SO₄ application show that high N input in ecosystems can amplify latent deficiency of mineral elements. Recently on many sites the risk of nutrient imbalances has developed as a consequence of improved N supply due to deposition. Thus, nutritional and site specific aspects should be payed more attention when liming and fertilization measures are planned. A higher percentage of deep rooting tree species as beech and fir could be useful for stabilizing mineral nutrition of forest canopies.     

Düngung mit gebranntem Magnesit und Magnesiumhydroxid zur Standortmelioration in einem stark geschädigten Fichtenökosystem

Fertilization with calcined magnesite and Mg-hydroxide for site amelioration in a heavily damaged Norway spruce ecosystem Fertilization experiments with calcined magnesite and Mg-hydroxide were carried out in a heavily damaged, 60-year old Norway spruce ecosystem at Hohe Matzen in the Fichtelgebirge/NE-Bavaria. The site is characterized by high atmospheric inputs with deposition rates of 1.25 kg H, 42 kg S, and 32 kg N per ha and year, and low pH-values of the soil (typic Dystrochrept derived from granite). The trees show severe symptoms of needle yellowing due to Mg-deficiency. Fertilization resulted in manyfold increased Mg-concentrations in soil solution down to 70 cm soil depth and a significant increase of pH down to 25 cm mineral soil depth. Nitrate concentrations were higher after fertilization, but decreased within 15–24 months below the control level. The higher solubility of the Mg-hydroxide resulted in an earlier and clearer pH-increase paralleled by a decrease of the NO₃-concentrations. As a mean over the whole experimentation period no increased N-output from the soil was found after hydroxide application. Fertilization also increased the amount of exchangeable Mg down to 40 cm mineral soil depth. Application of Mg-hydroxide leads to higher Mg-contents in recent-year needles three vegetation periods after fertilization. The lower solubility of magnesite results in a half- to one-year delay in its effects on soil chemical parameters with no reaction of the needle contents within this period.     

Amelioration of Magnesium Deficiency in a Norway Spruce Stand (Picea abies) with Calcined Magnesite

Norway spruce has shown needle yellowing and defoliation symptoms on manysites of the Bohemian Forest in north central Austria since theearly 1980s. A forest amelioration experiment was set up toevaluate the response of spruce to magnesite based fertilizerswith different solubilities. Response variables were a crownvigor index, diameter growth, nutrient contents in needles,soil solution chemistry, and soil chemistry. Soil solution atfertilized plots showed an immediate response in base cationconcentrations, nitrate concentrations and pH-values.Fertilization increased the pool of exchangeable cations in theupper 15 cm of the soil and reduced levels of exchangeable Al. Themagnesium and calcium content of the needles of dominant trees wasgreatly improved. Fertilization has increased the mineralizationrate of soil organic matter. Diameter growth, as a measure of treevigor, showed a pronounced positive response with a time delay of5 years. Our results demonstratethat magnesite based fertilizers are a viable option to improvethe nutritional status of spruce forests on granitic bedrock.     

Effects of forest vegetation on spatial variability of surface mineral soil pH,soluble aluminum and carbon

The purpose of this study was to examine spatial variability in forest soils at several levels including variability due to soil structure, to the presence of individual trees and to populations of different species of trees. Both classic statistical and geostatistical methods were used. Soil chemical properties measured include pH and Al and C in solution which was in equilibrium with the surface mineral soil. Results indicated that soil cores 1.8 cm in diameter were as effective as larger cores in incorporating variability in surface mineral soil pH. There was no spatial correlation in soil pH in samples separated by a distance of 20 to 360 cm. The presence of individual Norway spruce and red pine trees affected soil in their vicinity. Soil pH was depressed and soluble Al elevated. in soil near the base of the tree compared to soil 120 cm from the tree, independent of direction. In addition, in soil sampled at least 100 cm from the base of trees, pH was lower in Norway spruce compared to sugar maple plantations and soluble C was greater in red pine compared to Norway spruce plantations. It is concluded that in less than 50 yr the presence of individual trees and populations of different tree species can affect chemical properties of surface mineral soils. These effects should be considered in the design and interpretation of experiments.     

Crown Condition and Needle Chemistry of Norway Spruce in Relation to Critical Loads of Acidity in South-East Norway

This study shows that it is questionable if critical load modelling can contribute in the search for harmful effects of acid deposition on forest health at present. Critical loads forS and N deposition were calculated using the MAGIC and PROFILE models for more than 100 monitoring plots in Norway spruce forestin south-east Norway. The two models gave different results, likely due to differences in the models, including differences in the time spans applied. The PROFILE model gave considerably more plots with exceedance than the MAGIC model.At plots where the CL was exceeded, calcium/aluminium (Ca/Al) ratios in the soil solutions were low. However, very few of theseplots had possible harmful values of the Ca/Al-ratio. More than 50 yr seems in most cases to be needed to bring Ca/Al ratios below 1.0. Present deposition was better correlated with measured forest condition variables such as crown condition and needle chemistry,than with modelled exceedance according to any of the two methods. The deposition of S and N was weakly, negatively correlated to foliar concentrations of P and Ca, and positivelyto foliar N concentrations and crown density.     

Nutritional Status of Northern Spain Beech Forests Wate 4915

Fagus sylvatica L. is the most representative tree species in forests of Navarre (Northern Spain), in the boundary between the Euro-Siberian and Mediterranean regions. In this paper we assess the nutritional status of 30 beech forest stands selected in this area which belong to three vegetation series: Saxifrago hirsutae – Fageto sylvaticae S., Scillo lilio-hyacinthi – Fageto sylvaticae S. and Carici sylvaticae – Fageto sylvaticae S. We also determine the foliar content of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), nitrogen (N) phosphorus (P) and sulphur (S) for these stands. Additionally, the crown condition was also assessed. Average stand values for Ca, Na, Mg and K foliar content were found to be above the reference values in many of the stands. Consequently, macronutrient ratios for these elements (N/Ca, K/Ca, Ca/Mg and K/Mg) were either above or below the range considered to be suitable for the harmonious growth of beech trees, but no evidence was found that this had a deleterious effect on the health status of the beech trees. Results showed that crown condition in these stands was good, with an average 12.2% of trees considered as damaged compared to an EU 22.8% for the same period. No symptoms of N-saturation were found; on the contrary, N is believed to still be a limiting factor for tree growth in the area.     

Foliar symptoms,ethylene biosynthesis and water use of young Norway spruce (Picea abies (L.) Karst.) exposed to drought and ozone

Four-year old Norway spruce (Picea abies (L.) Karst.) trees were pretreated at low and high water supply, and then placed into a growth chamber containing four compartments so that two levels of ozone exposure, 0.02 and 0.4 Μl l^?1, could be replicated. They were exposed to ozone and drought stress for 59 days, and water use was determined by periodic weighing. Small effects of ozone treatment were detected on new shoot dry weight, and water use by trees receiving the high ozone treatment appeared higher. Both visual symptoms and ethylene biosynthesis showed that drought stress reduced damage to trees exposed to high ozone. Ethylene emission and 1-aminocyclopropane-1-carboxylic acid (ACC) levels increased after 18 days of exposure to 0.4 Μl l^?1 ozone, while visual symptoms were seen at 30 days. After 59 days of exposure to the combined stresses, ethylene and ACC levels were lower, but showed an ozone x water interaction. Most ethylene and ACC were produced by wet trees at high ozone concentration, but dry trees also had high ethylene and ACC levels at low ozone. Levels of needle malonyl-ACC (MACC) were not significantly affected by treatment, and did not change with time, but root MACC levels, which were twice needle levels, were high in wet trees at high ozone concentration, but also high in dry trees at low ozone concentration. These results suggest that drought stress occurring during ozone exposure could be expected to reduce damage to young Norway spruce, and that this damage may be related to ethylene biosynthesis.     

Throughfall of plant nutrients in relation to crown thinning in a swedish coniferous forest

Throughfall has been sampled in SW Sweden from 60 to 80 yr old Norway spruce (Picea abies) of two stands with different crown thinning classes, representing healthy reference trees and injured trees. the condition of the canopy had a significant influence on quantity and quality of deposition to the forest floor. Annual throughfall deposition from injured spruce showed an increase in glucose 270%, total sugar 80%, organic carbon (DOC) 40%, organic N 50%, Mg 100%, Ca 30%, and Fe 40% while Mn and K deposition decreased 30% and 20%, respectively, compared to annual throughfall deposition from healthy spruce.     

Soil chemical properties and nutritional status of trees in pure and mixed‐species stands in south Ethiopia

Interest in mixed‐species plantations in the tropics has increased because they appear to provide a wider range of options, such as yield, biodiversity, nutrient cycling, and C sequestration than pure stands. Pure stands of Pinus patula Schlecht. and Charm., Juniperus procera Hochst., and Grevillea robusta A. Cunn., and mixed stands of P. patula/G. robusta, P. patula/J. procera, and P. patula/Podocarpus falcatus R. Br. at Wondo Genet in S Ethiopia were studied to examine (1) the impact of mixed‐species plantations on soil chemical properties, and (2) the impact of mixed‐species plantations on the nutritional status of constituent trees. Soil (0–50 cm depth) and foliage samples were collected from four random plots (100 m²) in each of the pure and mixed‐species plantations. Soil samples were analyzed for organic C, N, and base cations. Foliage samples were analyzed for nutrients (N, P, K, Ca, and Mg). There were little significant differences in soil chemical properties and foliar nutrient concentrations of trees between the pure and mixed stands. Among pure stands, J. procera and G. robusta differed in soil exchangeable Ca⁺⁺ and K⁺ at 0–5 cm soil depth and in foliar P and Ca concentration. After 18 and 24 y, mixed stands did not influence soil chemical properties and tree nutrition differently than pure stands. This may be due to additive interaction in mixed‐species stands and the similarity of the constituent tree species in foliar nutrient concentration and their impact on soil chemical properties.     

Relationship between Norway Spruce Status and Soil Water Base Cations/Aluminum Ratios in the Czech Republic

There is a concern that soil acidification by acidic deposition, along with the resulting depletion of the labile pool of nutrient cations (e.g. Ca, Mg) and enhanced leaching of Al from soil may contribute to forest dieback. The molar ratios of Ca/Al or (Ca+Mg+K)/Al in the soil solution have been widely used as a criterion for risk of tree damage due to acidification. Intensity and quality of the crown and branch structure transformation due to formation of secondary shoots in successive series is a very sensitive indicator of long-term tree damage, and the subsequent regenerative processes. Soil water chemistry and crown structure transformation of Norway spruce were observed at 16 forest plots within the Czech Republic with the following results: parameters, expressing degradation processes in the crown (defoliation of primary structure), regeneration processes (percentage of secondary shoots) or synthetic stages of crown structure transformation showed high correlation with soil water (Ca+Mg+K)/Al ratio in organic horizons. No relationships were found for mineral horizons. The correlations between soil water and crown status parameters were considerably stronger when using the (Ca+Mg+K)/Al ratio rather than the Ca/Al ratio.     

Ozone and drought stress — Interactive effects on the growth and physiology of Norway spruce (Picea abies (L.) Karst.)

Young trees of Norway spruce (Picea abies (L.) Karst.) were grown in 120 litre pots under two different ozone levels in open-top chambers for three seasons, 1992–1994. The ozone treatments were charcoal filtered air (CF, average 24 h seasonal mean 6.5 ppb) and non-filtered air with extra ozone aiming to track 1.5 times ambient (NF+, average seasonal mean 34 ppb). In addition, half of the spruce trees in Aug – Sep each season recieved a drought period of between five and seven weeks. The remaining half were kept well-watered. The soil water content, the needle water potentials, and the gas exchange as well as the chamber micro climate were measured before, during and after the drought period. Furthermore, the growth of the trees was measured as biomass increase. During the 1993 drought period, where the trees experienced a moderate drought stress, the trees grown in NF+ consumed soil water faster and showed a higher needle conductance compared to CF. However, no negative effects were found on needle water potential or growth. During the more severe 1994 drought stress period we did not find any differences between the two ozone treatments in soil water consumption, needle conductance or needle water potential. There was a significant negative effect of the high ozone treatment on tree biomass of the well-watered trees. Total plant biomass was reduced 18 % and stem biomass was reduced as much as 28 %. The negative effect of ozone on tree biomass was much smaller for the droughted trees.     

Fertilization of declining conifer stands in the vosges and in the French Ardennes

Twenty fertilization experiments were set up in 1985 and 1986 in the Vosges mountains, using mostly calcareous or Mg fertilizers, in order to verify whether fertilization can attenuate defoliation and yellowing recently recorded in Silver fir and Norway spruce. In the Ardennes, a fertilization experiment set up in Norway spruce stands prior to the appearance of yellowing was assessed. In these areas, the total acid deposition is about 2 kg eq H⁺ ha^–1 yr^–1. Nitrogen deposition is much more important in the Ardennes (52 kg N ha^–1 yr^–1 in form of wet and dry deposition) than in the Vosges (16 kg N ha^–1 yr^–1). The results in the eight adult stands showed no uniform reaction to the treatments. Spontaneous improvement, further deterioration independently of the treatment, as well as a positive reaction to fertilization were observed. Additional N or P fertilization sometimes had a beneficial effect on Ca or Mg treatments. The selection of the stands with the best response turns out to be difficult, as the nutrient contents of needles alone seem not to be a satisfactory criterion for selection. Young plantations reacted positivley to the treatments. Soluble Mg fertilizer leads to an immediate response. Low solubility Ca-Mg fertilizers (Ca-Mg lime) did not produce reactions until three years after the application. In the Ardennes, in a 40 yr old spruce stand suffering from severe Mg deficiency, a Ca and Ca-phosphate fertilization applied 5 yr before yellowing appeared had positive effects on crown density, discoloration and wood production. Conversely, a single N fertilization in this experiment, as well as in a young plantation in the Vosges, had a marked negative effect on Mg nutrition, even at low levels.     

Fertilization of declining conifer stands in the Vosges and in the French Ardennes

Twenty fertilization experiments were set up in 1985 and 1986 in the Vosges mountains, using mostly calcareous or Mg fertilizers, in order to verify whether fertilization can attenuate defoliation and yellowing recently recorded in Silver fir and Norway spruce. In the Ardennes, a fertilization experiment set up in Norway spruce stands prior to the appearance of yellowing was assessed. In these areas, the total acid deposition is about 2 kg eq H⁺ ha⁻¹ yr⁻¹. Nitrogen deposition is much more important in the Ardennes (52 kg N ha⁻¹ yr⁻¹ in form of wet and dry deposition) than in the Vosges (16 kg N ha⁻¹ yr⁻¹). The results in the eight adult stands showed no uniform reaction to the treatments. Spontaneous improvement, further deterioration independently of the treatment, as well as a positive reaction to fertilization were observed. Additional N or P fertilization sometimes had a beneficial effect on Ca or Mg treatments. The selection of the stands with the best response turns out to be difficult, as the nutrient contents of needles alone seem not to be a satisfactory criterion for selection. Young plantations reacted positivley to the treatments. Soluble Mg fertilizer leads to an immediate response. Low solubility Ca-Mg fertilizers (Ca-Mg lime) did not produce reactions until three years after the application. In the Ardennes, in a 40 yr old spruce stand suffering from severe Mg deficiency, a Ca and Ca-phosphate fertilization applied 5 yr before yellowing appeared had positive effects on crown density, discoloration and wood production. Conversely, a single N fertilization in this experiment, as well as in a young plantation in the Vosges, had a marked negative effect on Mg nutrition, even at low levels.     

川西亚高山针叶林植物群落演替对生物学特性的影响

通过对川西亚高山针叶林人工重建过程中土壤微生物数量、酶活性及其与土壤养分性状的关系研究表明,云杉人工成熟林土壤微生物数量、酶活性明显低于云杉人工幼林地,也低于同龄的次生阔叶林地,人工云杉林随着林龄的增加土壤肥力严重退化。土壤微生物数量、酶活性与土壤有机质、全N、全P和碱解N等养分指标呈显著相关关系,土壤生物学指标能较好地反映土壤肥力状况。解决当前人工成熟云杉林土壤退化的主要措施应因地制宜地进行抚育间伐,改善林地的微生态条件,尽量避免营造针叶纯林,建议营造针阔混交林。     

川西亚高山针叶林植物群落演替对土壤性质的影响

研究了川西亚高山针叶林人工重建过程中土壤物理性质,结果表明:随着人工云杉林龄的增加,土壤表层粉粒、粘粒、物理性粘粒、团聚度和结构系数降低,砂粒含量增高,土壤饱和持水量、毛管持水量及总孔隙和毛管孔隙在人工云杉林演替过程中表现出"U"型变化,即人工云杉从幼林向成熟林演替阶段,土壤饱和持水量、毛管持水量及总孔隙和毛管孔隙则减少,在40年生云杉林达最低值之后,随着云杉自疏而有上升的趋势,毛管持水量是决定林地土壤自然含水量的主要因子。为了加速该区域植被恢复和重建过程,建议营造针阔混交林和对人工成熟林和过熟林进行间伐抚育,增加物种多样性,减少水土流失,为植物生长创造良好的土壤物理环境。