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1.
During a two year research period from 1992 to 1993, samples of different species of trees were taken in 17 forest stands located in Navarra, Spain. From these samples, bark extracts were prepared in which the pH and the conductivity were measured. The health of the sampling trees was also evaluated by determining the degree of defoliation and decoloration of the canopies. The bark tissue analysis revealed the presence of an environmental acidity gradient that decreased from NW to SE. This coincides with the location of important sources of pollution and their course of transport and dispersion. On the other hand, in the samples ofQuercus ilex a significant correlation between the pH and the defoliation levels (P≤0.01, r=0.62) was found. This fact reveals the potential usefulness of tree bark as a health bioindicator of trees.  相似文献   

2.
Two large-scale national monitoring campaigns investigating changes in spruce bark extract acidity and long-term monitoring of bark acidity along elevation transects have been carried out in the Czech Republic. The investigations have revealed significant average changes in the pH values of bark extracts (4 g: 16 ml) from 2.35 to 2.60 between 1989 and 1995, and from 2.60 to 3.25 between 1995 and 2005. In comparison with 1990, the H+ concentrations in bark extracts had decreased by 10–15% in 1995 and by 70% in 2005. National emissions of acidic compounds were reduced by about 58% (1995) and 62% (2005), and the mean annual H+ deposition was reduced by about 60% (1995) and by about 80% (2005). However, neither inventoried current absolute amounts nor specific regional amounts of emitted acidic pollutants correlated significantly with bark acidity in 1995 and 2005. Bark acidity was not significantly affected by the elevation of the sampling plots or by the average tree defoliation. Along the altitudinal transects, considerably defoliated trees near the top of mountain ridges showed permanently lower bark acidity than trees lower down the mountain slopes. Significant differences in average bark acidity were found between defined mountain, highland and lowland elevation zones. In 2005, the epiphytic lichen Hypogymnia physodes was found at almost all sampling plots, with the exception of the most industrialised areas of two coal basins. The abundance of the lichen correlated significantly and negatively with spruce bark acidity and with total nitrogen and copper concentrations in moss growing at the bark sampling plots in 2005.  相似文献   

3.
The research was carried out in the spruce forests of Barania Góra (Silesian Beskids, Poland) affected by pandemic dying of trees. Twenty-seven samples were collected from the O layer in two plots: 17 in a cut down forest infested with insect pests (bark beetle) and ten in a 120-year-old healthy forest. The analyses covered basic parameters (pH(H2O), pH(KCl), w(org), C(tot), N(tot), CEC) and the concentrations of aluminium in the fractions leached with 0.1?M BaCl(2) (Al(exch)), 0.5?M CuCl(2) and 0.1?M Na(4)P(2)O(7) (Al(bio)) solutions. The total aluminium concentration in the soil was assayed digesting samples with hydrofluoric acid. The effect of pH and organic matter content on the amount of exchangeable (Al(exch)) and bioavailable (Al(exch)) aluminium in the soil was analysed. It has been found that the soils in both plots are strongly acidic and contain 550 to 1,700?mg?kg(-1) of exchangeable aluminium and 1,200 to 4,800?mg?kg(-1) of bioavailable aluminium. The lack of disease symptoms in the spruce trees in plot 2 can be explained by the higher content of organic matter in the soil. Unfortunately, one might expect that the high concentration of exchangeable aluminium will also cause the trees in the area to wither.  相似文献   

4.
The rising cost of peat and pine bark has boosted the demand for alternative organic materials for container growing media. Here, composts of invasive acacia (Acacia longifolia and Acacia melanoxylon) residues were evaluated as alternative organic materials for horticultural substrates. Compost bulk density was less than 0.4 g cm?3 and total pore space was more than 85 percent of the total volume, as established for an ideal substrate. The matured acacia compost air capacity, easily available water, buffering capacity, and total water-holding capacity were also within acceptable recommended values. With increased composting time the physical characteristics of the composts were improved, but the same was not true for chemical characteristics such as pH and electrical conductivity. The replacement of pine bark compost by acacia compost in a commercial substrate did not negatively affect either lettuce emergence or lettuce growth, suggesting that acacia compost can be successfully used as an alternative component for horticultural substrates.  相似文献   

5.
Little effect of forest age on oribatid mites on the bark of trees   总被引：1，自引：0，他引：1  
This study investigates the effect of forest age (20-, 50-, 160-year-old, and primeval forest) on oribatid mite communities on the bark of oak trees in the National Park Pusza Białowieża in eastern Poland. We hypothesized that oribatid mite diversity on bark peaks at forests of intermediate age and that the number of parthenogenetic species of oribatid mites is highest in young stands. In contrast to these hypotheses, the diversity, density, number of juveniles, community structure and the mode of reproduction of oribatid mite species were not significantly affected by forest age. None of the oribatid mite species occurred exclusively on trees of a specific age. The results suggest that oribatid mite communities on the bark of trees are minimally affected by tree harvesting regimes. In contrast to oribatid mites in soil, communities on bark appear to be less sensitive to disturbances.  相似文献   

6.
Changes of the qualitative and quantitative features of snow and rain during the winter and the vegetation period, respectively, were studied during three years (1997–1999). The sites were located on Che?mova Góra Mt. in the Ojców National Park (South Poland), which is one of the most polluted areas in Poland. Standard methods of measuring bulk precipitation were used according to the ICP Forest Manual. One plot was near the summit part (OPN2), and the other plot was in the lower part close to the foot (OPN5) of the Che?mowa Góra Mt. The total amount of Ca decreased during the study period, while NO3 ? and SO4 ?2 decreased only in the vegetation period. During the winter period the snow carried high amounts of Cl?, NO3 ?, SO4 ?2, Na, Mg, and Ca. A decrease in pH was noticed during the winter periods, whereas an increase in pH was found during the vegetation period. Higher element concentrations were always found in the upper plot compared to the lower situated plot. This indicated that the upper and more exposed parts of the mountains in the Park were under higher pollution stress.  相似文献   

7.
Air pollution emissions were not continually monitored in the Upper Silesian Industrial District (USID), southern Poland, and data is only available for the last 20?years. Long-lasting and severe tree ring reductions in pines growing 5-20 km north of the USID area recorded particularly high levels of air pollution emissions in the period 1950-1990. Especially high amounts of reductions and many missing rings were found in the period 1964-1981. At the same time, pines growing 60?km west of the USID do not record deep ring reductions; this proves that the phenomenon is of a regional nature. Increases in infant mortality and lung, bronchial, and tracheal cancer morbidity rates among males were also recorded in the USID during periods of high air pollution. Infant mortality rates increased several years after the tree ring reductions. Therefore, it may be possible to use tree ring reductions as an early indicator of the occurrence of adverse effects on human health.  相似文献   

8.
As part of the PIRLA projects, diatom-pH transfer equations were used to infer past lakewater chemistries from dated sediment cores. Diatom inferred lakewater acidification appeared to show a strong subregional pattern within Florida. Five lakes were examined from in or near the Trail Ridge region (in the north-central peninsula) and all showed some evidence of recent acidification (>.20 pH units decrease) probably related to acidic deposition. Lakes hi the Panhandle region and the Ocala National Forest (south of Gainesville) did not show evidence of recent anthropogenic acidification, although few acidic clearwater lakes hi the Panhandle were examined. Paleolimnological studies have provided strong evidence for acidification due to acidic deposition in a small subset of lakes from various regions of the United States. This subset is defined geographically by different acidic deposition rates and bedrock types, and by the many limnological factors that contribute to lake pH and buffering capacity. Unfortunately, it is also defined by the small numbers of lakes that have so far been studied.  相似文献   

9.
Several hypotheses have been put forward to explain the causes of damage to plants by atmospheric pollution. None however, fully explain why some species are more prone to damage than others. In the literature, certain higher plants are more commonly reported as suffering damage from atmospheric pollution. These include climax species such as conifers, some broadleaf species such as oak and beech, and ericaceous species. Pioneer species such as highly nitrophillous woody species and ruderal herbaceous species are seldom reported in connection with damage from atmospheric pollutants. A screening of 18 species (woody and herbaceous) for 5 physiological and metabolic parameters and subsequent regression analysis of the data, showed that plants could be grouped according to their tolerance to acidity. There was a marked positive correlation between leaf nitrate reductase (NR) activity and the buffering capacity index (BCI) of the leaf. Foliar mistings and soil applications of 3 mol m?3 KNO3 to 6 assorted plant species also revealed that pioneer species, can induce NR activity when NO3 ? is applied directly to the foliage or soil. However, climax species have a much lower ability to increase NR activity in response to foliar and soil NO3 ? inputs. Leaf NO3 ? assimilation carries with it the direct generation of OH?, involves greater uptake of base cations and confers greater physiological buffering capability through the close interaction of carbon and nitrogen acquisition in the leaf. The hypothesis states that leaf nitrate assimilators are physiologically more competent at buffering acidic inputs whether directly as H+, or indirectly through uptake of acidic pollutants.  相似文献   

10.
Natural abundances of carbon-13 and nitrogen-15 were analyzed in 3-year bands of annual rings of three red pine (Pinus densiflora Sieb. et Zucc.) trees in eastern Korea to elucidate their variations in relation to changing environmental conditions, particularly air pollution. Tree ring width had a trend to decrease with time (r = ?0.79, P < 0.001); however, tree-ring indices did not show any consistent pattern of change over time. Tree ring indices were correlated neither with the respective precipitation nor temperature. The δ13C (range: ?25.7 to ?24.4ä) of tree rings became less negative as tree ring indices increase (r = 0.43, P < 0.05), suggesting that radial growth of trees might have been affected by environmental factors such as nutrient deficiency and acid rain that affect carboxylation efficiency. Increasing N concentration (range: 0.40 to 0.68 g N kg?1) with decreasing δ15N (range: +4.2 to ?0.6ä) of tree rings (r = ?0.84, P < 0.01) during the period (since 1980s) of increasing NO x emission in Korea was consistent with the hypothesis that increasing deposition of N depleted in 15N may lead to 15N depletion in tree tissues. However, quantitative information on inter-ring translocation of N which may cause N isotopic fractionation is necessary to use the δ15N signal as a reliable indicator of air pollution.  相似文献   

11.
To determine the geological distribution of acid buffering capacity and exchangeable Al of forest soils in Japan, surface soils under forest vegetation were collected nationwide from a total of 1,034 sites. Generally, surface soils in Japanese forests are mostly acidic and low in both exchangeable cation content and exchangeable Al. The median of soil pH(H2O), total exchangeable cations, and exchangeable Al are 5.1, 76 mmol(+)Kg?1, and 19.6 mmol(+)kg?1, respectively. Acid buffering capacities of selected soils were determined using a soil column, which was comparable to the capacity that resulted from cation exchanges with protons. Soils with high buffering capacity and low exchangeable Al are widely distributed in Japan, and overlap with the areas of Andisol distribution. Volcanogenic materials seem to mask soil characteristics derived from underlying geology even though they are not Andisols. However, central to western Honshu Island, Shikoku Island, and northern Kyushu Island showed weak acid buffering capacities with high exchangeable Al potential in surface soils.  相似文献   

12.
The relationship between plant‐available silicon (Si) soil concentrations and bark Si concentrations in coniferous species is poorly understood. The objectives of this research were to generate baseline data on Si concentrations in soils and bark of Sitka spruce (Picea sitchensis) seedlings in Ireland and to understand better the relationship between soil and bark Si concentrations. Seedlings were harvested from eight plantation forestry sites and two tree nurseries, and Si concentrations in the bark tissue as well as plant‐available Si concentrations in soils (CaCl2 extractant) were measured. Bark Si concentrations varied significantly between sites and were lowest [mean 790 (± 242 SD) mg kg?1 dry plant tissue] on acidic, organic rich peat soils, while the highest Si concentrations occurred in seedlings [mean 3688 (± 633 SD) mg kg?1 dry plant tissue] grown on soils with low C concentration and higher pH values (≈ 4.5 to 5.5 in H2O). Plant‐available Si soil concentrations were not related to soil C concentrations. There was a negative (but statistically not significant) relationship between plant–soil concentrations and soil pH. A significant negative relationship was observed between plant‐available soil Si concentrations and bark Si concentrations, which may be related to the presence of soil from mixed soil horizons forming the mounds that seedlings were planted on. Uptake and sequestration of Si by seedlings may have been related to the rate of growth of the seedlings, as bark Si concentrations were highest on sites that were expected to have greater seedling growth rates. The negative relationship between bark and plant‐available Si soil concentrations suggest that uptake of Si by Sitka spruce is rejective at higher concentrations.  相似文献   

13.
Flowering and height growth of 20 Scots pine (Pinus sylvestris L.) populations from 10 countries were analyzed at two replicated provenance sites established in 1984 in western Poland. One site was 2 km from a phosphate fertilizer factory that emits SO2 and fluorides, and the other 12 km to the southeast in an area free of acute air pollution levels was treated as a control. Slow-growing populations from the southern (40 to 45°N) and northern (58 to 61°N) part of the species range exhibited relatively smaller air pollutioninduced growth reductions than those from the central part of the range (45 to 58°N). Trees growing in the control area started flowering 4 yrs earlier than those at the polluted site. The percent of trees flowering at the control site differed significantly among provenances in both 1988 and 1990. The mean percent of trees with flowers was three times lower at the polluted site. The least sensitive southern and northern provenances in terms of pollutioninduced reductions in growth exhibited the largest pollution-induced decreases in flowering. These findings indicate that the sensitivity of vegetative organs to air pollution stress is not always paralleled by the sensitivity of reproductive organs.  相似文献   

14.
《Journal of plant nutrition》2013,36(7):1513-1526
Abstract

Many tropical plant species originated in areas with acidic soils and do not grow well in calcareous (high pH) soils. It is impossible to acidify soils that have high contents of calcium carbonate in south Florida. Replacing calcareous soils with acidic soils obtained from distant regions is an alternative. Unfortunately, such introduced acidic soils may eventually be neutralized by irrigation and ground water that is saturated with calcium carbonate. The objective of this investigation was to examine the acidity changes and buffering capacities of three types of acidic soils (silica sand soil, red loamy sand soil, and a mixed soil) used to establish tropical plants in a rainforest exhibition at Fairchild Tropical Garden, Miami, FL. The three areas were excavated to remove native calcareous soil, limestone bedrock, and filled with acidic soils. Various rainforest plants were planted. Soil samples were collected in contiguous 10 cm‐deep segments from the soil surface to the bedrock shortly after deposition of the soils and one year later. Soil pH, EC, particle distribution, buffering capacity were determined. Results showed that both silica sand and mixed soils had been neutralized and the soil pH values had risen over 7 in all soil depths after one year. However, less than 10 cm of the surface and bottom soil layers of red loamy sand had been neutralized and the soil pH in the middle of soil profile remained unchanged due to its higher buffering capacity. A column leaching study showed that the acidity in the red loamy sand soil would be neutralized by irrigation water and by capillary movement of groundwater with a high concentration of calcium bicarbonate. Buffering curves indicate that it is easier to maintain acidity in sandy soil than of loamy sand and mixed soils with acidified irrigation water. Indeed it is difficult to acidify the mixed soils with high organic matter content after these soils have been neutralized.  相似文献   

15.
Ninety potted red spruce saplings enclosed in open-top fumigation chambers were exposed to O3 (charcoal-filtered air, non-filtered air, 1.5 × ambient, or 2 × ambient) and simulated rain (pH 3.1, 4.1 or 5.1) for two growing seasons (June to October). Foliage was sampled for mineral nutrients, total soluble sugars, and starch in September 1988 at the end of the second season of exposures. The development of cold tolerance of individual trees was assessed using the electrolyte leakage technique. Ozone and simulated rain treatments had marginal effects on mineral nutrient concentrations of current and 1 yr old foliage. Ozone did not affect foliar carbohydrate levels but the simulated rain treatments of pH 3.1 tended to depress levels of total soluble sugars and starch in 1 yr old foliage and of starch in current year's foliage. During mid to late October, the current year's foliage of trees receiving rain of pH 3.1 was less tolerant to cold than the current year's foliage of trees receiving rain of pH 4.1 or 5.1. Following the October period, trees in all three acidic rain treatments had similar tolerances to cold.  相似文献   

16.
Previous soil and spring water analyses in small catchments revealed low pH values in the spring water during high discharge events. This paper analyses the potential which small scale heterogeneity of soil acidity may have to explain decreasing spring water pH as a result of high discharge. Soil aggregates were collected from a C‐horizon of a Spodosol in the Fichtelgebirge. Exchangeable cations and soil solution were examined on both samples from the surfaces and the cores of aggregates which were obtained by a mechanical separation procedure. The Reuss‐Johnson soil chemical equilibrium model was used to predict soil and spring water pH values as a function of acidic input and soil air CO2 concentration in equilibrium with both aggregate fractions. Ranges of acidic input from 160—570 μeq L−1 and soil air CO2 concentrations from 0.1 to 3 Vol. % were considered. The model predicted spring water pH values from 5.0 to 5.3 for the acidic aggregate surface samples (base saturation = 12.5%) and from 6.8 to 7.2 for the aggregate core samples (base saturation = 32.1%). The results suggest that small scale acidity gradients may expand the range of predictable spring water pH values. However, very low pH values (<5) still need additional explanation.  相似文献   

17.
ABSTRACT

Evaluation of the plant-available phosphorus (P) in calcareous soils is commonly performed by removing a portion of solid phase P using chemical extractants. Critical soil test values, however, may be affected by variation in sorption and buffering behavior of different soils. The objective of this study was to evaluate the importance of buffering capacity indices to predict P uptake by wheat (Triticum aestivum). Eleven surface soil samples were assayed for a number of P intensity (CaCl2-P) and quantity (Olsen-P, Colwell-P, and Resin-P) factors. Some phosphorus buffering indices were obtained from P sorption equations. A single-point index of buffering was also determined experimentally. In a greenhouse experiment, wheat was grown for 35 and 70 days on the same soils and P uptake was determined. Nonlinear and linear equations described the P sorption data (P < 0.001). Buffering indices derived from these equations were highly correlated with single-point index of capacity. Clay content was the most important soil property affecting the buffering capacity factor. The phosphorus intensity index (CaCl2-P) was weakly related to P uptake (P < 0.05). Among the quantity factors only Resin-P was significantly correlated with P uptake. Buffering indices showed significant but inverse relationships with P uptake only at 70 days harvest (r = ?0.69 to ?0.71; P < 0.05). Combination of intensity or quantity factors with buffering capacity indices, such as intensity/capacity or quantity/capacity indicators, improved considerably the ability to account for variations in P uptake by wheat.  相似文献   

18.
Identification of trees with key microhabitats as well as knowledge of their ecological formation is important for the conservation of epiphytic bryophytes and lichens on beech. Based on the hypothesis that certain types of stem damage are crucial for the occurrence of epiphytes of conservation concern, we surveyed 145 beech trees (57-280 years) for different types of stem damage and analysed their relationship to other tree characteristics, epiphyte species and wood-inhabiting fungi in a forest landscape on acid soils.Three main types of stem damage were identified; canker, rot hole and surface rot. The incidence of rot holes was highest on trees with a low growth rate during the last 50 years, but was unrelated to tree size or age per se. Bark pH was significantly higher below than above rot holes, whereas no such relationship was found for cankers. Wood mould from rot holes had a very high pH, explaining the higher bark pH below this type of damage. The number of epiphyte species of conservation concern was strongly positively related to rot holes and high bark pH. Cankers had a weaker, yet significant positive effect. The fungus Psathyrella cernua was associated with the rot holes and is suggested to be a key species involved in creating this microhabitat.We conclude that slow-growing trees with rot holes are important for the conservation of epiphytes and should be selected as retention trees in managed forests. The study also highlights a potential for habitat restoration by inducing artificial damage and inoculation of decay fungi in beech trees.  相似文献   

19.
The condition around coniferous trees in the soil is becoming gradually acidic when acid rain falls continuously. Nutrient uptake by the roots of coniferous trees could be affected in such environmental change of root zone. The experiments of water culture of coniferous seedlings in modified systems were carried out using (2-and, 3-year-old) of Japanese cedar(Cryptomeria japonica) and, Japanese cypress(Chamaecyparis obtusa) that are the typical Japanese forest trees. Nine major nutrients such as Na+, NH4 +, K+, Ca2+, Mg2+, Cl?, NO3 ?, PO4 3?, and SO4 2?, were given in the water culture solution and growth of trees was observed for two years. The aspects of nutrient uptake by these seedlings and the effects of acidity in culture solution were observed. The following results were obtained. 1) Japanese cedar of 50% and Japanese cypress of 30 % in tested seedlings could live for two years. 2) All Japanese cedar and cypress that started in the strong acidic condition ( pH=3.0) were dead within three months. 3) The minimum pH value in the acidic condition is estimated as 3.2 for these coniferous seedlings, and it means that they can live at least for two years in this condition. 4) The seasonal pattern of the uptake of nitrogen nutrient by Japanese cedar was determined.  相似文献   

20.
Air pollutant emissions from the industrial complex of Cubatão, SE-Brazil, have caused a severe decline of the Atlantic Forest in that region. In order to test the influenceof air pollution on the mineral nutrition of trees, leaves of the native species Tibouchina pulchra Cogn. (Melastomataceae), Miconia pyrifolia Naud. (Melastomataceae) and Cecropia glazioui Snethl. (Cecropiaceae) were sampled during winter and summer seasons at four sites with different pollution characteristics. Additionally, saplings of T. pulchra were cultivated in uniform soil and exposed to ambient air at the same experimentalsites for periods of 16 weeks. In both kinds of leaf samples, the concentrations of macro-nutrients were determined and nutrient ratios calculated. In leaves of mature T. pulchraand C. glazioui growing at polluted sites N, P and S levels were significantly higher than in trees from the reference area. With respect to K contents, C. glaziouishowed an increase, T. pulchra a decrease when compared to reference trees. Mg and Ca concentrations generally did not exhibit great variations. As a consequence of the changes in mineral contents nutrient ratios (N/K, N/Ca, S/K, S/Ca) shifted to higher values. The results of the exposure experiments together with data on pollutant concentrations inambient air and rain water demonstrated that atmosphericdeposition to the plants and pollution effects on the soilchemistry are the main reasons for the observed alterations inmineral nutrition of trees.  相似文献   

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