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1.
We exposed momi fir (Abies firma Sieb. et Zucc.) seedlings to simulated acid fog of pH 3.0 for about 3 years (from July 1999). During the last year of acid fog exposure, half of the seedlings were subjected to rhizosphere Al stress (complex stress) and the nutrient status of seedlings was determined. Chronic acid fog exposure decreased Fe and Zn concentrations in current-year and 1-year needles, and Al in 1-year needles, but had little effect on major element concentrations. Aluminum treatment had a broad impact on nutrient status in fine roots and needles. In fine roots, increases in Al and Cu concentrations and decreases in B, Mn, and Zn concentrations were observed. In 1-year needles, Al treatment increased Al, B, and Mn concentrations and decreased Cu concentration. The complex effect of acid fog with aluminum on nutrient status was relatively slight. These results show that changes in nutrient status under chronic acid fog exposure and/or Al stress are induced before the decline of photosynthesis in momi fir seedlings, mainly due to Al stress.  相似文献   

2.
In order to clarify the chronic influence of acid fog on the gas exchange rates of momi fir (Abies firma Sieb. et Zucc.) trees, we exposed them to simulated acid fog (pH 3) for 3 years. The composition of the acid fog was similar to that observed in a region where momi fir trees have been declining, and it contained organic acids. We then treated the firs with various additional stresses, such as drought, low temperature, fine root cutting, ozone exposure, soil acidification, nitrogen load, and rhizosphere aluminum stress. Under chronic exposure to acid fog, the momi fir seedlings exhibited a pattern of stomatal behavior whereby they excessively opened in summer and closed in winter. Furthermore, the stomata of these seedlings tended to open during drought stress, and their needles were visibly injured after ozone exposure. The net photosynthesis rates of the seedlings exposed to acid fog were regulated by their stomatal aperture, rather than directly by acid fog. These results suggest that acid fog exposure disturbs the control of stomatal function in the momi fir seedlings. In addition, we found that chronic acid fog exposure suppressed the decrease in net photosynthesis rate, due to its nitrogen load.  相似文献   

3.
The decline of virgin fir (Abies firma) forest at Mt. Oyama has been reported. Related field observations suggest that high acidity fog is linked with its decline. However, cedar (Cryptomeria japonica) in the same area shows no symptoms of decline. For assessing effects of acid fog on membrane-bound calcium (mCa) of the leaf mesophyll cells, 9-year-old seedlings of fir (Abies firma) and 8-year-old seedlings of cedar (Cryptomeria japonica) were exposed twice a week to simulated acid fog (SAF at pH 3 with pH 5 as control) for 2 h per day in a chamber during May–December 2007 (except August). Current and 1-year-old needles were collected from seedlings and analyzed at 1-month intervals. For current-year needles of fir, mCa levels in cells exposed to SAF at pH 3 were significantly lower than in cells exposed to pH 5, especially during September 2007–March 2008. In contrast, it is noteworthy that mCa levels of cedar were maintained as virtually constant irrespective of SAF acidity, indicating that fir is more sensitive to acid fog than is cedar. Based on these results, mCa loss by acid fog might also be caused in the declining virgin fir forest at Mt. Oyama.  相似文献   

4.
杉木对低磷胁迫的响应和生理适应机制   总被引:1,自引:0,他引:1       下载免费PDF全文
[目的]研究低磷胁迫对杉木幼苗各种抗氧化酶等生理指标的变化影响,探讨抗氧化酶活性与杉木耐低磷能力的关系,揭示低磷胁迫下杉木养分吸收的适应机制,阐明杉木体内生物大分子对低磷胁迫的响应。[方法]通过设置不同磷浓度(0、0.25、0.50、1.00 mmol·L~(-1))Hoagland营养液,模拟低磷胁迫试验,测定低磷胁迫对杉木幼苗的生理指标的影响,研究低磷胁迫对杉木幼苗养分吸收的影响机制以及测定杉木幼苗不同部位的光谱特性。[结果]随着缺磷程度的增加,杉木幼苗中SOD活性、CAT活性以及叶绿素a、叶绿素b和叶绿素总量均先升后降,根系中POD活性呈现出升高的趋势、MDA含量先降再升后降,叶片中POD活性和MDA含量先降后升。低磷胁迫对杉木幼苗根系和叶片吸收利用营养元素有显著影响。杉木苗根系所含的Mn随着缺磷程度的增加呈上升趋势,而Al和Cu先降后升,Fe和K则有所下降,Ca先升后降。此外,杉木叶片中Fe和Mn的积累量呈降低的趋势,Cu和K先升后降。低磷胁迫对杉木幼苗根系和叶片组织在3 367、2 924、1 736、1 630、1 380、1 150 1 000 cm~(-1)处特征峰吸光值影响不同。[结论]低磷胁迫下,杉木幼苗的根系和叶片会通过改变保护酶(SOD、CAT和POD)活性抑制MDA形成,降低膜脂过氧化对细胞膜系统的破坏,通过增加对其他养分元素的吸收来规避损伤以及通过改变不同部位糖类、氨基酸和蛋白质等物质含量来适应低磷环境。  相似文献   

5.
杉木幼龄林叶片营养元素含量与林木生长的相关性   总被引:3,自引:0,他引:3  
本文重点论述丘陵立地条件下 ,1、2代杉木幼龄林高生长、当年高生长、胸径生长与叶片中营养元素N、P、K、Ca、Mg、Cu、Mn、Zn、Fe含量的相关关系 ,进而从林木营养这个角度 ,为提高林木产量、防治地力衰退提供可靠的科学依据。研究结果表明 :2代杉木幼龄林生长与N、P、Mg、Cu、Mn、Fe含量呈密切的正相关。 1代杉木幼龄林生长虽与P、Mg、Cu、Mn、Fe含量呈正相关 ,但复相关系数数值偏低。也就是说土壤养分含量尚没有明显影响 1代杉木幼龄林正常生长  相似文献   

6.
对大花序桉幼苗生物量及营养元素进行测定,结果表明,大花序桉苗木平均单株生物量大小排序为茎>根>叶。幼苗主要营养含量和吸收积累规律为K>N>P>Fe>Mn>Zn>B>Ca>Cu>Mg。大量元素N、P、K贮量最高的部位均为茎,根部和叶中含量相近。大花序桉苗期叶片对主要营养元素N、P和K的吸收分配间存在相互促进的关系;Mg与Ca,Cu与P、K,Zn与N、K、Cu、Fe,Fe与N呈现互相促进关系;Mn与N、Fe、K、Cu,B与P、Cu为相互抑制关系。据此,大花序桉苗期以氮、磷、钾肥为主,其中要求养分K2O>N>P2O5,并有针对性地添加铁肥、锌肥和铜肥。  相似文献   

7.
We evaluated how the variability of nutrient concentrations affects their suitability as quality attributes. Foliar elements of four batches of three-year-old bareroot Scots pine seedlings, 150 seedlings from each batch, were analyzed. The variability in the concentrations of N, P, and K was small (coefficient of variation in a batch was 11–12), that of Ca and Zn intermediate (CV 19–21), and that of Mg, Mn, Fe, Al, Cu and Na was large (CV 26–35), being close to the variability in morphological attributes. Micronutrients varied more than macronutrients and a larger sample would be needed to estimate these concentrations with the same precision. Correlations between seedling size and nutrient concentrations in needles were small. Positive and negative correlations were found among nutrient concentrations, but not large enough to allow us to predict concentrations with each other. For concentrations of some nutrients the variance within batches was smaller than was found for morphological attributes in both relative and absolute terms, which provides support for batch culling.  相似文献   

8.
Temporal variation in nutrient concentrations of Scots pine (Pinus sylvestris L.) needles was studied during a three‐year period in three stands of differing stages of development. Concentrations of N, P and K varied significantly between years; this variation was related to differences in needle dry weight. Concentrations of all measured nutrients (N, P, K, Ca, Mg, Mn, Cu, Zn, Fe, B) and Al varied between seasons; this variation was related to nutrient mobility and the annual physiological cycle. Concentrations of the mobile nutrients N, P and K decreased in spring and early summer during shoot and needle elongation and increased in late summer and autumn during needle senescence and litterfall. Concentrations of Mg, Cu, Zn and B followed somewhat similar patterns. The poorly mobile nutrients Ca, Mn and Fe accumulated gradually in needles during each growing season. Needle nutrient concentrations were stable during the nonactive period.  相似文献   

9.
Teak (Tectona grandis L.f.) is widely planted in the world due to its high market demand, economic, ecological and social value. Its plantations have mostly been established and expanded into sites that are acidic to severely acidic in southern China. But, there are no available and specific evidence-based nutrient management techniques. To better recognize and understand the relationship between teak tree growth and nutrient content in the foliage and soil and establish nutrient norms are critical to optimally manage these young plantations. We studied the foliar nutrient and soil chemistry in 19 representative teak plantations aged 5–8 years. Regression analysis indicated that the mean annual increment of teak volume was linearly and positively correlated with foliar N, Ca, Fe and B concentrations, with soil base saturation percentage, available P and Zn concentrations, and negatively correlated with soil Al concentration. Only if the Ca and Mg contents in soil were enhanced, could the increase in soil base saturation percentage benefit teak growth. A revised classification of low-and high-yielding stands was established by using a sorting method of principal components over 6 foliar macro and 8 micro elements in a Diagnosis and Recommendation Integrated System (DRIS). Specific DRIS norms for teak plantations in acid soils were derived. The nutrient balance of N, P, K Ca, Mg, Zn, B with Fe or Al, Ca with Mg, and Fe with Al provided a key to promote the growth of teak in acid soils. Meanwhile, soil Zn was also found as a primary trace element that affected teak growth in this study.  相似文献   

10.
Pollution often causes visible symptoms of foliar injury. The injury is sometimes associated with an increase in the accessibility of toxic elements to plants as a result of acidification of the soil. We investigated the distribution of elements (N, P, K, Ca, Mg, Mn, S, Fe, B, Cu, Zn, Al, F, Pb, Cd, Cr, Ni and Co) in healthy current-year needles of Scots pine (Pinus sylvestris L.) growing at an unpolluted control site and at a site polluted mainly by SO(2), HF and Al(3+) from a fertilizer factory established in 1917. Needles from both sites were sampled before the appearance of visible injury and cut into five sections of equal length (tip, base and three middle parts). The mean concentrations of major nutrients were 20-30% lower in needles at the polluted site than in needles at the control site, whereas the concentrations of aluminum and fluorine were higher in needles at the polluted site. An increase in concentration from needle base to tip was detected for N, Fe, B, and Al at both sites and for Mn only at the polluted site. Fluoride accumulated in the tips of needles only at the polluted site, which could explain the necroses of needle tips at this site. The distribution of elements along the length of the needles was influenced by pollution, element mobility and the distal accumulation of toxic elements.  相似文献   

11.
贵州都匀马尾松种子园针叶DRIS营养诊断分析   总被引:1,自引:0,他引:1  
通过对都匀1.5代无性系种子园20年生马尾松针叶中N、P、K、Ca、Mg、Cu、Zn、Fe、Mn、B等营养元素含量变化的测定和分析,初步筛选出N/P、K/N、Ca/N、Mg/N、N/Cu、zn/N、N/Fe、K/P、Ca/P、P/Mg、P/Cu、P/Zn、Fe/P、K/Ca、K/Mg、K/Cu、K/Zn、Fe/K、Ca/Mg、Ca/Cu、Ca/Zn、Fe/Ca、MgJCu、Zn/Mg、Fe/Mg、Zn/Cu、Fe/Cu、Fe/Zn共28对元素比值为重要参数,对贵州都匀马尾松种子园针叶作DRIS营养诊断分析。结果表明,该地区马尾松针叶内Mn含量过高,平均值为767.01mg/kg,而B含量较低,仅为12.95mg/kg,马尾松的需肥顺序为Cu〉P〉Zn〉Mg〉Ca〉N〉K〉Fe。  相似文献   

12.
13.
Nutrient retranslocation from existing foliage of singleleaf pinyon pine (Pinus monophylla Torr. & Frem.) did not meet the nutrient demands of new needles on the same branch. Singleleaf pinyon pines, with an average age of 177 years, located at an elevation of 2300 m on a ridge in The Sweetwater Range in Nevada, USA retained needles for 18 or more years and increased needle number per branch by 17-18% annually. With age, needles gained weight and accumulated Ca, Mg, Fe, Zn, P, and Mn. The amount of N per needle showed no consistent trend with needle age. Only Cu and K declined in concentrations and amounts with needle age and these differences were not statistically significant. Retranslocation of nutrients at needle abscission could provide only 2 to 13% of the N, P, K, Fe, Cu, and Mg required by new needles. We conclude that nutrient capital in existing foliage constitutes a long-term nutrient reserve for the tree rather than a mobile nutrient pool.  相似文献   

14.
Allocation of biomass and nutrients to shoots and roots was followed for three years in fast and slow growing populations of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), a fast growing pioneer species, and amabilis fir (Abies amabilis Dougl. ex J. Forbes), a slow growing shade-tolerant species. Seedlings were grown for three seasons in five nutrient treatments containing varying proportions of nitrogen and phosphorus (N:P). In both species, growth was greatest in the 250:20 N:P treatment followed by the 100:60 and 100:20 treatments. Vector analysis showed that, in both species, relative to the 100:20 treatment, seedlings in the 20:20 treatment were N deficient and seedlings in the 100:4 treatment were P deficient, i.e., where deficiency is defined to mean that an increase in nutrient supply increases nutrient content, nutrient concentration and plant dry weight. Seedlings in the 100:60 treatment had a higher P content than seedlings in the 100:20 treatment but the same dry weight, indicative of what Timmer and Armstrong (1987) termed luxury consumption. No nutrient retranslocation was observed in either species until the third growing season. In Douglas-fir, the greatest percentage of nutrients was exported from one-year-old shoots between May and July of the third growing season to support new growth. The total amount and percent of nutrients retranslocated was higher in Douglas-fir than in amabilis fir. Amabilis fir seedlings also exported N and P from older shoots, but this was later partially replenished. In both species, P retranslocation was greatest in treatments with a high N:P ratio. Nitrogen retranslocation was greatest in amabilis fir seedlings in treatments with a low N:P ratio, and greatest in Douglas-fir seedlings in the 250:20 and 100:60 treatments. Potassium retranslocation was correlated with seedling size. Douglas-fir retranslocated more of its shoot N reserves into new growth at the expense of older needles when soil fertility was high and sinks were strong. Otherwise, both species preferentially translocated the elements in short supply. Thus, retranslocation varied with the ecological characteristics of species, the relative availability of soil nutrients and sink strength.  相似文献   

15.
Zusammenfassung Die Gelbf?rbung von Fichten im Südschwarzwald betrifft vor allem die ?lteren Nadeln; der jüngste Nadeljahrgang ist jeweils grün. Wir untersuchten die zeitliche Entwicklung der Vergilbung durch Chlorophyll- und Elementanalysen. Die Vergilbung der letztj?hrigen Nadeln setzt mit dem Knospenaustrieb im Sp?tfrühjahr ein und ist mit einer starken abnahme der Gehalte an Mg und Zn gekoppelt. N, P, K, und S ver?ndern sich nur wenig. Fe und Al, weniger stark Ca und Mn, nehmen mit dem Nadelalter zu. Cu, Pb und Cd zeigen keine Korrelation mit dem Vergilbungsgrad Ein Anstieg des Chlorophyllgehaltes ist nur schwach ausgepr?gt. Aus dem zeitpunkt des Vergilbens und den Ver?nderungen der Elementgehalte schlie?en wir, da? Mobilisierung und Verlagerung von unzureichend angebotenen N?hrelementen (Mg, Zn) die Vergilbung der Nadeln ma?geblich beeinflussen.
Chronological change in chlorophyll and element contents in the needles of a yellow-chlorotic spruce stand
Summary The yellow discoloration of spruce in the southern Black Forest primarily affects the older needles; the current year's needles remain green.We investigated the chronological development of yellowing through chlorophyll and element analyses. The discoloration of last year's needles begins at bud burst in late spring and occurs along with a great decrease in the contents of Mg and Zn. N, P, K. and S are scarcely altered. Fe and Al, less so Ca and Mn, increase with needle age. Cu, Pb, and Cd show no correlation with the degree of yellowing. An increase in chlorophyll content is only weakly pronounced. From the onset of yellowing and the changes in element contents we conclude that mobilization and translocation of the deficient nutrient elements (Mg, Zn) decisively influence needle discoloration.
  相似文献   

16.
Models of the effects of elevated concentrations of aluminum (Al) on growth and nutrient uptake of forest trees frequently ignore the effects of mycorrhizal fungi. In this study, we present novel data indicating that ectomycorrhizal mycelia may prevent leaching of base cations and Al. Mycorrhizal and non-mycorrhizal Pinus sylvestris L. seedlings were grown in sand obtained from the B-horizon of a local forest. In Experiment 1, non-mycorrhizal seedlings and seedlings inoculated with Hebeloma cf. longicaudum (Pers.: Fr.) Kumm. ss. Lange or Laccaria bicolor (Maire) Orton were provided with nutrient solution containing 2.5 mM Al. Aluminum did not affect growth of non-mycorrhizal seedlings or seedlings inoculated with L. bicolor. Seedlings colonized by H. cf. longicaudum had the highest biomass production of all seedlings grown without added Al, but the fungus did not tolerate Al. Shoots of seedlings colonized by L. bicolor had the lowest nitrogen (N) concentrations but the highest phosphorus (P) concentrations of all seedlings. The treatments had small but significant effects on shoot and root Al concentrations. In Experiment 2, inoculation with L. bicolor was factorially combined with the addition of a complete nutrient solution, or a solution lacking the base cations K, Ca and Mg, and solutions containing 0 or 0.74 mM Al. Seedling growth decreased in response to 0.74 mM Al, but the effect was significant only for non-mycorrhizal seedlings. Mycorrhizal seedlings generally had higher P concentrations than non-mycorrhizal seedlings. Aluminum reduced P uptake in non-mycorrhizal plants but had no effect on P uptake in mycorrhizal plants. Mycorrhizal colonization increased the pH of the soil solution by about 0.5 units and addition of Al decreased the pH by the same amount. We conclude that the presence of ectomycorrhizal mycelia decreased leaching of base cations and Al from the soil.  相似文献   

17.
The low availability of nitrogen (N) is believed to be one of the major limiting factors of forest regeneration in Iceland and frequently under Boreal conditions. Lutz spruce (Picea x lutzii Littl.) seedlings were nutrient loaded using four fertilization regimes in the end of nursery rotation in autumn 2008 and planted in the following spring, with or without a single dose of fertilizer, on two treeless sites in N-Iceland with contrasting soil fertility. Measurements were made after one growing season. The highest loading level without additional field fertilization increased new needle mass by 122% and 152%, for the poor and more fertile site, respectively. The highest loading level with field fertilization increased new needle mass equally, by 188% and 189%, for the poor and more fertile site, respectively. Retranslocation of N, from old needles to current needles, increased with more loading. However, it was clear that nutrient loading could not replace field fertilization, as the seedlings generally showed an additive response to field fertilization and nutrient loading; doing both always gave the best results in seedling performance. As the study only covers field establishment during the first year, the long-term effect of nutrient loading of Lutz spruce cannot be predicted. However, it was concluded that loading might provide an additional input for faster plantation establishment during the first growing season after planting.  相似文献   

18.
Harvest residue decomposition can significantly contribute to nutrient and heavy metal exports to receiving water courses. This study monitors the nutrient and heavy metal dynamics in decaying Sitka spruce and lodgepole pine harvest residue needles on Atlantic blanket peat forests in the west of Ireland. Using the litterbag method, harvest residue was placed both within and between furrows in two uncut forest and two clear-cut sites. On the clear-cut sites, the litterbags were positioned outside the harvest residue piles (i.e. brash windrows). Over the 2-year monitoring period, the needles decomposed slower at the clear-cut sites than the uncut forest sites, with mass losses of 46–55 and 58–77 %, respectively. Approximately 20 % less phosphorous (P) was released from the decaying needles at the clear-cut sites, while nitrogen (N) was released only at the uncut sites. Tree species was a significant factor contributing to nutrient and heavy metal release and accumulation patterns, with higher concentrations of aluminium (Al), nickel (Ni), cadmium (Cd) and zinc (Zn) in the decaying spruce needles than in pine. Conversely, the spruce needles showed accelerated depletion of calcium (Ca) and magnesium (Mg) relative to the pine. The harvest residue needle positioning (inside furrow/between furrows) and the site soil characteristics contributed significantly to Al transformations in spruce needles and iron (Fe) in both spruce and pine needles, with more accumulation occurring inside the furrows where Al and Fe contents of the peat were high. Manganese (Mn) was released from the needles in three of the four sites with a total release of over 90 % within 2 years. In the remaining site, where the Mn content of the peat was high, an accumulation of Mn in the needles was observed. The decomposition of needles on blanket peat catchments may be a significant source of P to receiving water courses, owing to their fast release of P, but not a likely source for N export.  相似文献   

19.
Effects of Al on growth, nutrient uptake and proton efflux were studied in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings grown for about nine months in culture solutions with a pH between 3.4 and 3.6 and with both calcium and magnesium (Ca + Mg) at a concentration of 0.1, 0.5 or 2.5 mM. In the absence of Al, plant dry matter production and root development increased with increasing concentrations of (Ca + Mg) in the culture solution. At the low and intermediate (Ca + Mg) concentrations, optimal root and shoot development were observed at an Al concentration of 4 mg l(-1). At the highest (Ca + Mg) concentration, Al up to 4 mg l(-1) did not affect growth, but at higher concentrations, it significantly reduced both shoot and root growth. As the concentration of (Ca + Mg) in the nutrient solution increased, the concentrations of Ca and Mg increased in shoots and roots also. The concentrations of Ca and Mg in the roots were unaffected by the presence of Al, whereas in the shoots they were either unaffected, or increased, by Al. Concentrations of Al in, or on, roots, or in shoots, did not change in response to changing concentrations of Ca + Mg in the nutrient medium. In general, concentrations of P and K in shoots and roots were higher in seedlings grown in nutrient solutions containing Al. Stimulation of growth by moderate concentrations of Al, which was observed at suboptimal (Ca + Mg) concentrations, was associated with a low NH(4) preference and a low root proton efflux. The Al-induced increase in internal K concentration and reduction in NH(4) preference may be explained by a lower efflux of K and NO(3), respectively.  相似文献   

20.
The distribution in tree biomass and understorey vegetation and annual biological and geochemical cycling of total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were measured in young, middle-aged and mature plantations (8-, 14- and 24-years old) of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) in southern China. Although >98% of nutrients occurred in the soil, soil nutrient content decreased with plantation age. Nutrient outputs from the soil exceeded inputs in stands of all ages but the net soil nutrient loss increased significantly for N, P and Ca with plantation age. Comparison of nutrient fluxes showed that the smallest (and hence limiting for nutrient cycling) fluxes were litter decomposition in the young plantation in contrast to canopy fluxes (apart from for Mg) in the middle-aged and mature plantations. Nutrient use efficiency, release of nutrients from litter decomposition and nutrient return, particularly in litterfall, increased significantly with plantation age. These results suggest that, as stand age increases, nutrient cycling in Chinese fir plantations is increasingly dominated by biological processes and becomes less dependent on external nutrient sources in rainfall and the soil. It therefore appears that prolonging the rotation length of Chinese fir plantations by approximately 5 years could be beneficial for maintaining the soil nutrient status for successive plantings.  相似文献   

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