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1.
不同树龄库尔勒香梨叶片养分特征分析   总被引:3,自引:0,他引:3  
为了掌握不同树龄库尔勒香梨树体的养分平衡特征,从而为库尔勒香梨园的科学施肥提供技术指导,选择新疆特色果树库尔勒香梨作为研究对象,测定了不同树龄段库尔勒香梨叶片的养分含量,并统计分析了其叶片养分含量的变化特征。结果表明:库尔勒香梨叶片中的氮含量随着树龄的增加而减小,钾含量随着树龄的增加而增大,磷、镁含量均随着树龄的增加先减小后增大,钙含量随着树龄的增加先增大后减小,铁、锰、铜、锌的含量均随着树龄的增加而表现出增加—减小—增加的变化趋势;不同树龄段之间,随着库尔勒香梨树龄的增加叶片氮、磷、钾、铁、锰、铜含量间的差异均逐渐减小,而其钙含量间的差异却显著,镁、锌含量间的差异不显著;不同树龄段库尔勒香梨叶片养分含量的变化表现基本一致,叶片氮、磷、镁、铜、锌的含量均处于梨叶片营养元素适宜含量范围内,钾、铁含量均高于梨叶片营养元素适宜含量的上限值,锰含量低于梨叶片营养元素适宜含量的下限值,钙含量处于梨叶片营养元素缺乏状态。  相似文献   

2.
Studies of post-fire soil status in Mediterranean ecosystems are common;however,few have examined the effects of long-term forest management after a wildfire on physicochemical soil properties.Here,we analyzed differences in soil properties attributable to long-term postfire management and assessed the sustainability of these management practices in relation to the soil properties.The study area is located in Odena in the northeast region of the Iberian Peninsula consisted of the control forest(burned more than 30 years ago),low density forest(LD;burned in a wildfire in 1986 and managed in 2005)and high density forest(HD;burned in a wildfire in 1986 and no managed).For soils from each plot,we measured soil water repellency,aggregate stability,total nitrogen(TN),soil organic matter(SOM),inorganic carbon(IC),pH,electrical conductivity,extractable calcium,magnesium,sodium,potassium(K),phosphorus,aluminum(Al),manganese(Mn),iron(Fe),zinc,copper,boron,chrome,silicon and sulfur and calculated the ratios of C/N,Ca+Mg/(Na+K)^1/2,Ca/Al and Ca/Mg.Significant differences were found in TN,IC,SOM,pH,K,Al,Mn,Fe and C/N ratio(p<0.05).All soil properties were found to have largely recovered their pre-fire values.Soils were affected by the post-fire management practices implemented 20 years after the fire,as reflected in their respective physicochemical properties,so that soil properties at the control and LD sites are more similar today than those at the control and HD sites.Thus,sustainable forest management can overcome soil degradation in areas affected by wildfire in the medium-and long-term by improving soil properties.  相似文献   

3.
This study investigated the effects of Ips typographus (L.) damage on initial litter quality parameters and subsequent decomposition rates of oriental spruce tree species [Picea orientalis (L.) Link]. The needle litter was collected from highly damaged, moderately damaged and control stands on two aspects (north and south) and two slope position (top and bottom) on each aspect. The litter was analyzed for initial total carbon, lignin and nutrient (nitrogen, phosphorus, potassium, calcium, magnesium and manganese) concentrations. The variability in nitrogen and calcium concentrations and ratios of C:N, lignin:N and lignin:Ca was significantly affected by the insect damaged levels. While nitrogen concentrations in needle litter increased with increasing insect damage (and consequently the ratios of C:N and lignin:N decreased), calcium concentrations decreased (and consequently the ratio of lignin:Ca increased). Aspect and slope positions explained most of the variability in carbon, lignin, phosphorus, potassium, magnesium and manganese concentrations and lignin:P ratio between all studied stands. Litter decomposition was studied in the field using the litterbag technique. The litter from highly damaged stands showed highest decomposition rates followed by moderately damaged and control stands. The mass loss rates were significantly positively correlated with initial nitrogen concentration and negatively with C:N and lignin:N ratios. The effects of microclimate resulting from canopy damage on litter decomposition was also examined at the same time using standard litter with the same litter quality parameters, but they showed no significant differences among the insect damage levels indicating that alteration of the litter quality parameters produced by I. typographus damage played a more important role than altered microclimate in controlling needle litter decomposition rates. However, changes in microclimate factors due to topography influenced decomposition rates.  相似文献   

4.
The effects of wood ash or wood ash plus nitrogen (N) fertilization on soil chemical properties, needle nutrient concentrations and tree growth were studied in five coniferous stands, aged 31–75 yrs, after 5 and 10 yrs. In each experiment 3 t ha?1 of loose wood ash was applied to three replicated plots (30×30 m). In three of the experiments 120–150 kg N ha?1 was applied together with the same wood ash (WAN). These three experiments also included a stand-specific fertilization (SSF) treatment, which consisted of 120, 150 or 180 kg N ha?1. Five years after wood ash or WAN application the pH increase in the humus layer was 1–1.7 pH-units and in the 0–5 cm mineral soil layer 0.3–0.4 pH-units. The increase was approximately the same 10 yrs after application, and was also associated with an increase in pH in the 5–10 cm mineral soil layer. Wood ash or WAN significantly increased both the total and extractable calcium and magnesium concentrations in the humus layer on all the sites. Wood ash or WAN had an increasing effect on the boron concentrations, but a decreasing effect on the manganese concentrations in the needles. Wood ash had no significant effect on the volume growth. The trees on the WAN plots grew as well as or slightly better than those on the SSF plots.  相似文献   

5.
以22年生坪田白果为试验材料,对白果中微量元素与土壤营养因子的相关关系进行研究,为银杏精准施肥,提升白果品质提供依据。采用SPSS软件对银杏果园中土壤因子指标和白果中微量元素含量进行简单相关、偏相关分析。结果表明:白果中微量元素之间及白果中微量元素与土壤营养因子之间具有不同程度的相关性。简单相关分析筛选出7组各自具有显著或极显著相关的因子,分别是:白果中铜、锌、镁和土壤有效硼,白果中铜、土壤交换态镁、土壤速效钾、土壤有效硼,白果中锰、硼和土壤pH、土壤交换态钙,白果中锰、土壤速效钾、土壤交换态钙,白果中硼、土壤有效磷、土壤有效锌、土壤有效铜,白果中锰、土壤有机质、土壤全氮,白果中硼、土壤pH、土壤有效铁、土壤交换态钙。偏相关分析结果表明:土壤有效硼对银杏吸收铜、锌、镁等微量元素具有显著的抑制作用,可有效抑制银杏协同吸收锌镁;土壤交换态镁对银杏吸收铜,土壤有机质对银杏吸收微量元素锰,土壤有效磷对银杏吸收微量元素硼均具有较强的抑制作用;土壤pH对银杏吸收微量元素硼具有较强的促进作用。作物对微量元素的吸收受到多种因素的影响,如生境条件、土壤环境条件、土壤营养因子交互作用、施肥方式方法、栽培技术、作物品种等,相关性分析可为多变量因子提供统计学意义上的相关关系度量刻度,筛选出显著性指标,指导施肥生产实践。建议加强提升白果微量元素机理机制的研究,并开展银杏相关施肥试验;在银杏生产中,建议减少农家肥用量,叶前肥和催花促种肥适当增施石灰,提升土壤pH,在3—6月以叶面喷施方式增施硼肥,达到催花促种的目的。  相似文献   

6.
Autumnal changes in organic-S, sulfate-S, total-S and the ratios of organic-S to total-N and sulfate-S to organic-S were followed in leaves and adjacent bark of actinorhizal (Frankia-nodulated) black alder (Alnus glutinosa (L.) Gaertn.) and eastern cottonwood (Populus deltoides Bartr. ex Marsh.) trees growing on a minespoil site high in extractable soil sulfate, and in black alder and white basswood (Tilia heterophylla Venten.) trees growing on a prairie-derived soil in Illinois. Organic-S concentrations decreased significantly (P < 0.05) during autumn only in foliage of trees growing on the prairie-derived soil where losses of leaf organic-S were 65% for black alder and 100% for white basswood. Leaf sulfate concentrations were relatively stable throughout autumn in white basswood growing on prairie-derived soil and in black alder at both sites. Sulfate-S concentrations in leaves were significantly (P < 0.05) higher in trees at the minespoil site than in trees growing in the prairie-derived soil (5.1 mg g(-1) for the minespoil site and 1.2 mg g(-1) for the prairie-derived soil), and in the non-actinorhizal species during late summer. During the autumn, the ratio of organic-S to total-N doubled in leaves of eastern cottonwood at the minespoil site, but in black alder and white basswood growing on the prarie-derived soil, it decreased by 60 and 74%, respectively. Organic-S concentrations in bark increased more during autumn in species unable to fix atmospheric N(2), than in black alder. The results suggest that patterns of autumnal translocation of leaf S can be site-dependent and that leaf S and leaf N are, at least in part, translocated independently in the fall. Black alder and eastern cottonwood seemed to incorporate sulfate-S readily into organic substances in leaves when grown in soils with a high sulfate content.  相似文献   

7.
Scots pine (Pinus sylvestris L.) seedlings of a provenance from northern Sweden were cultivated hydroponically for 7 weeks in a climate chamber. The nutrient solution contained either 2.5 (low-N) or 50 (high-N) mg N l(-1) with other essential elements added in a fixed optimal proportion to the nitrogen. After 5 and 7 weeks, the seedlings were analyzed for growth, total nitrogen and other essential nutrients, protein and free amino acids. Low-N seedlings grew more slowly and had higher root/shoot ratios than high-N seedlings. With respect to total nitrogen, the effect of the lower nutrient supply was mainly on the nitrogen content of the whole plant and the allocation of nitrogen among tissues, not on tissue nitrogen concentration. This was also the case for potassium, phosphorus, calcium and magnesium. The proportions by weight among these macronutrients in the whole seedlings were similar in both nutrient regimes. The proportion and concentration of sulfur were significantly lower in low-N seedlings than in high-N seedlings, because of a lower net uptake of sulfur than of other macronutrients. The shoot, needles and stem of low-N seedlings had higher concentrations of free amino acids and lower concentrations of protein than the shoot, needles and stem of high-N seedlings. Arginine dominated the pool of free amino acids in the low-N seedlings, whereas glutamine predominated in the high-N seedlings. We conclude that Scots pine seedlings accumulated soluble nitrogen as arginine when net protein synthesis was limited by factors other than nitrogen availability. Nutritional imbalance, as revealed by growth characteristics and a suboptimal proportion and concentration of sulfur in the seedlings, probably affected synthesis of S-amino acids, resulting in the diversion of assimilated nitrogen to arginine instead of protein.  相似文献   

8.
云浮市油茶适生区土壤中量元素分析   总被引:1,自引:1,他引:0  
选择云浮市 15 个镇(街道)的森林土壤钙、镁、硫含量为研究对象,比较分析其空间变异 性。结果显示:研究区森林土壤交换钙含量在 0.232~0.984 g · kg -1 之间,含量较高的有富林和高村,含量 较低的为云城和河口;森林土壤交换镁含量在 0.048~0.095 g · kg -1 之间,含量较高的有高村和都杨,含量 较低的为云城和高峰;森林土壤全硫含量在 0.126~0.235 g · kg -1 之间,含量较高的有思劳和石城,含量较 低的为腰古和高峰;土壤交换钙、交换镁间存在极显著的正相关关系,交换钙与全硫间存在极显著的负 相关关系,交换镁与全硫间则没有显著的相互关系。  相似文献   

9.
用原子吸收光谱法测定云南省红河州4县生产的茶叶及茶汤中矿物元素的含量,研究云南红河州茶叶中矿物元素以及不同冲泡次数茶汤中矿物元素浸出率的变化规律。结果表明:云南红河州茶叶含有丰富的矿物元素,矿物元素浸出率有较大差异,同种元素在不同茶叶中的浸出率略有差别。茶汤中矿物元素含量顺序为镁>锰>钠>钙>锌>铜>镍>铁。矿物元素浸出率以第一道茶汤最高,而后随冲泡次数的增加而降低。  相似文献   

10.
Increasing demand for renewable energy and limiting CO2 emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants.  相似文献   

11.
The foliar chemistry of diseased and healthy trees was studied one growing season after severe reduction in living crown caused by Gremmeniella abietina in four young Scots pine (Pinus sylvestris) stands. Sample trees were chosen pairwise on the basis of the living crown length: a diseased tree with about 50% live crown reduction and a healthy tree in each pair. Fifteen elements were determined in the youngest healthy needles on the lateral top shoots of each sample tree. Diseased trees had higher foliar boron, manganese and sodium concentrations and lower magnesium, iron, zinc, copper, potassium, nitrogen and sulphur concentrations compared to the healthy trees. Foliar calcium, aluminium, phosphorus, carbon and hydrogen concentrations did not differ between the diseased and healthy trees, except for P and A1 in two of the stands when the stands were analysed separately. Significant correlations between the needle element concentrations and crown ratio (length of the living crown/tree height) were found especially for B (increasing B with decreasing crown ratio) and for Mg, Fe and Zn (decreasing concentrations with decreasing crown ratio). The effect of G. abietina-induced living crown reduction on tree nutrient status and the role of these mineral nutrients in the susceptibility are discussed.  相似文献   

12.
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   

13.
Summary The condition of Scots pine (Pinus sylvestris) forests polluted by complex industrial emissions in the Prebaikalia region (East Siberia) is described using an eco‐physiological approach. Prebaikalia is one of the largest industrial areas of Russia. On 54 study plots the following needle parameters were measured: percentage of defoliation, protein nitrogen, nonprotein nitrogen, soluble carbohydrates, starch, aluminium, cadmium, calcium, copper, fluorine, iron, lead, magnesium, manganese, mercury, potassium, sodium, sulphur and zinc. The physiological condition of the pine tree stands was recorded on the basis of the protein nitrogen/nonprotein nitrogen ratio and the percentage of defoliation. Both parameters showed significant correlations with the accumulation of most pollutants. Five main damage classes were identified by a cluster analysis. The spatial distribution of these damage classes within the region is presented in a map.  相似文献   

14.
Fine roots and ectomycorrhizal root tips were sampled in a Norway spruce (Picea abies (L.) Karst.) stand in the eastern part of the Belgian Ardennes. The cellular and partly subcellular localizations of aluminum and lead were identified by the micro-analytical laser microprobe mass analysis (LAMMA) technique. In fine roots with secondary structure, localization of aluminum was limited to the peripheral cell layers. Lead was found in the outer layers, and also in the primary phloem. Aluminum penetrated the mycorrhizal mantle, but lead was seldom detected in ectomycorrhizae.  相似文献   

15.
选用4种常见的市售蜂蜜,采用原子吸收分光光度法测定其钙、镁、铜、铁、锌、锰6种微量元素的含量(mg/kg)。实验结果表明,4种蜂蜜当中微量元素含量丰富,其中钙元素含量34.2~54.60mg/kg,镁元素含量在9.54~10.72mg/kg,铜元素含量1.28~7.22mg/kg,铁元素含量23.86~51.39mg/kg,锌元素含量1.56~2.73mg/kg,锰元素含量2.63~3.07mg/kg。此法回收率96.4%~103.8%,标准偏差0.06%~0.63%。  相似文献   

16.
16种城市绿化树种叶片中铁锰铜锌元素的含量特征   总被引:1,自引:2,他引:1  
于2003年对昆明、思茅、丽江3市不同程度污染地段、不同季节16个绿化树种叶片中的铁、锰、铜、锌4种重金属元素的含量进行了测定。依据其结果进行分析,此16个城市绿化树种对Fe、Mn、Cu、Zn 4种重金属元素的吸收能力不同,叶片中Fe含量最高的树种是冬樱花;叶片中Mn含量最高的树种是咕山含笑;叶片中Cu含量最高的树种是冬樱花;叶片中Zn含量最高的树种是咕山含笑。4种元素总含量最高的树种是咕山含笑,为1 125.64 mg/kg;最低的是栾树,为324.05 mg/kg,相差达3.47倍。叶片中Fe和Cu含量的相关性达到极显著的水平,其他元素之间相关性均不显著。在石楠、麻栗坡含笑、滇润楠、天竺桂、云南拟单性木兰、杜英、山玉兰、冬樱花8个绿化树种中,有的树种叶片中Fe、Cu的含量与空气中可吸入颗粒物污染指数间有显著或极显著的正相关性,可做为监测树种;而此8个树种叶片中Mn、Zn的含量与污染指数间的相关性显著。  相似文献   

17.
A gradient survey was carried out in order to compare peroxidase activity in Scots pine (Pinus sylvestris) needles in relation to distance from the industrial centre of Monchegorsk, on the Kola Peninsula in north-western Russia. Apoplastic and total peroxidase activity and sulphur (S), nickel (Ni) and copper (Cu) content in the needles of mature trees were measured on seven plots located between 10 and 110 km from the pollution source. Peroxidase activities in both current- and previous-year needles increased towards the smelters and showed a positive correlation with needle S, Cu and Ni concentrations. Total peroxidase activities showed a more obvious relationship to the pollution gradient in winter than in autumn. The element contents in the current year needles averaged 1649 ppm (S), 128 ppm (Ni) and 118 ppm (Cu) close to the smelters, 1212 ppm (S), 37 ppm (Ni) and 67 ppm (Cu) at a distance of 40 km and 831 ppm (S), 7 ppm (Ni) and 1 ppm (Cu) at the most distant sampling plot.This study showed that both the apoplastic and total peroxidase activities responded to heavy metal and sulphur pollution up to 40 km from the smelters in winter, which indicated an increased oxidative stress in this area. The harsh climate conditions and the high pollution levels may have had additive effects. However, as peroxidases are considered a general indicator of stress, it is not possible to evaluate the extent to which single pollutants contribute to this enzyme activity.  相似文献   

18.
薛煜  吴兴印 《林业科技》1992,17(3):21-24
试验结果表明,在病级不同的樟子松针叶内,无机元素的含量不同。1年生罹病针叶内Fe的含量高于健康林木针叶内铁的含量,2年生针叶内Mn、Cu、K的含量随病级的增高而增加,3年生病叶内Fe的含量比健康林木的高2.7倍,4年生病叶内K、Cu、Mn的含量随病级的增高而增加。  相似文献   

19.
We evaluated photosynthetic gas exchange and the accumulation of iron, manganese and sulfur in seedlings of five mangrove species (Aegiceras corniculatum (L.) Blanco, Avicennia marina (Forsk.) Vierh., Bruguiera gymnorrhiza (L.) Lamk., Hibiscus tiliaceus L. and Rhizophora stylosa Griff.) growing under anoxic soil conditions at low irradiance. Seedlings of the viviparous mangroves showed no significant responses to root anoxia. The presence of ferrous sulfate or manganous sulfate had a smaller effect on CO(2) assimilation, transpiration rate and stomatal behavior than the presence of sodium sulfide. Sodium sulfide inhibited photosynthetic gas exchange and caused complete stomatal closure in all species. Stomatal closure was probably the result of the damaging effect of sulfide ions on root cell membranes. Some leaf epinasty and wilting were also observed in response to the Na(2)S treatment in all species. A combination of FeSO(4), MnSO(4) and Na(2)S had a smaller effect on photosynthesis than Na(2)S alone, especially for Avicennia marina and Rhizophora stylosa seedlings, which maintained appreciable rates of CO(2) assimilation (2.49 and 3.84 &mgr;mol m(-2) s(-1), respectively) in the presence of all three phytotoxins. Roots of phytotoxin-treated seedlings of all species accumulated significant amounts of the corresponding toxin compared with roots of the control plants. The FeSO(4) or MnSO(4) treatments had no effect on foliar concentrations of iron or manganese, whereas the Na(2)S treatment resulted in an accumulation of S in the leaves of all species. Interactions between Fe(2+) and Mn(2+) and sulfide in the culture medium appeared to reduce their uptake by the seedlings. We conclude that high concentrations of sulfides in mangrove sediments may adversely affect both growth and survival of mangrove seedlings at low irradiances.  相似文献   

20.
叶片对植物的生长、发育和生活史的完成具有极其重要的作用,叶生物量(叶量)及其养分含量将直接影响树体对光能的接收与利用,而土壤为植物的生长发育提供了所需的养分元素。本研究对不同年龄毛竹的叶量、叶片和土壤养分含量及其相互关系进行了研究。结果表明:(1)毛竹叶量随着径阶的增大而增大。(2)5块样地中,样地1和3的毛竹叶量明显高于其他3块样地,样地4的毛竹叶量最小。(3)毛竹叶片中镁含量随着年龄的变化差异不显著(p>0.05);氮、总磷、有机磷、钾、钙含量在1度毛竹叶片与其他年龄毛竹叶片含量差异显著(p<0.05);2度以上各年龄毛竹叶间氮含量差异显著(p<0.05);毛竹叶无机磷含量仅1度竹叶与4度竹叶含量差异显著(p<0.05);叶片中的氮磷比值(N/P)随年龄增加先增大后减小;相同年龄不同径阶毛竹的叶片养分含量虽有变化却不存在显著差异(p>0.05)。(4)竹叶中氮含量与有机磷、全磷、钾、钙含量呈极显著相关(p<0.01);总磷、无机磷、有机磷含量与钙、钾含量显著相关(p<0.05);钾与钙含量呈极显著负相关(p<0.01)。(5)毛竹林土壤pH值与叶片镁含量显著负相关(p<0.05);土壤中镁含量与叶片中钙含量显著负相关(p<0.05),而与叶片全氮、总磷、有机磷、镁含量呈极显著负相关(p<0.01)。  相似文献   

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