Nutritional Status of Pollen and Needles of Diverse Pinus Sylvestris Populations Grown at Sites with Contrasting Pollution

Pollen may serve as a biological indicator for air pollution stress in plants. However, knowledge of pollen mineral composition and its relationship to environmental and genetic factors is very limited. We studied the concentrations of macro- and micronutrients in pollen and needles for seven European Scots pine (Pinus sylvestris L.) populations grown in two 15-yr-old provenance plantations with contrasting pollution levels. One site was located near a phosphate fertilizer factory, and the other in an area free of acute air pollution. We also tested the relationship between tree age and pollen nutrient composition by sampling 60-yr-old trees of local origin in both sites. No population differences were found in nutrient concentrations in pollen. However, there were significant differences among populations in needle concentrations of K, Mg and Zn, as well as significant site x population interaction for Mn concentration. In pollen, populations at the polluted site had significantly higher concentrations of S, Mn, Al, Na, Cu, Ni and Cd, and lower Zn. Average concentrations of S, P, Mn and Cd was lower in pollen of 60-yr-old than 15-yr-old Scots pine trees. Pollen concentrations of P, K, Ca, Mg, Fe and B were similar between sites and not related to the concentration of these elements in needles. Therefore, by analyzing the chemical composition of pollen it is not possible to detect any nutritional disorders for P, K, Ca and Mg in plants, and it seems unlikely that nutrient analyses of pollen have an advantage over analyses of foliage as a bioindicator of pollution. However, enhanced accumulation by pollen of such elements as Al, S, Mn, Cu, Ni and Cd at the polluted site may adversely affect pollen function.     

Element Concentrations in Scots Pine Needles on Radial Transects Across a Subarctic Area

Concentrations of aluminium (Al), arsenic (As), calcium (Ca), cadmium (Cd), chlorine (Cl), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), lead (Pb), sulphur (S), silicon (Si) and zinc (Zn) were measured by X-ray fluorescence spectrometry (XRF) in Scots pine needles collected from transects across Finnish Lapland and the Kola Peninsula in Russia. Ni, Cu, Fe, P and S concentrations were significantly higher in the needles collected in the vicinity of the smelters in Monchegorsk, whereas Mn and Zn decreased towards Monchegorsk. No distinct increase of S or decrease of Mn and Zn concentrations in the needles were observed when approaching Nikel. Foliar S concentrations were higher in C needles than in C+1 needles, even in plots close to the smelters. The effect of the emissions from the smelters was clearly seen in the needle chemistry up to 50 km away from smelters and was still perceivable over 100 km away.     

脐橙幼苗新老叶片养分含量对大、中量元素短期缺乏的差异性响应

  【目的】  对比大、中量养分短期缺乏下脐橙新、老叶片中11种必需元素含量及变化,并分析缺素导致的营养元素间的相互影响。  【方法】  以一年生枳砧纽荷尔脐橙幼苗为试材进行了砂培试验。以完全营养液为对照 (CK),设置缺氮 (?N)、缺磷 (?P)、缺钾 (?K)、缺钙 (?Ca)和缺镁 (?Mg)处理,测定不同处理脐橙叶片（老叶和新叶）生长指标及矿质元素含量。  【结果】  所有缺素处理均导致叶片叶绿素含量降低,生物量减少,以缺氮处理最为显著。缺氮降低了叶片N、Ca、Cu、Mo含量;缺磷降低了叶片P、K、Mo含量;缺钾降低了叶片K含量;缺钙降低了叶片N、Cu、Zn、Mo含量但增加了P含量;缺镁降低了叶片Ca、Mg、Zn、Mo含量但增加了K含量。以必需矿质元素为变量分别对各处理老叶和新叶进行主成分分析,老叶中第一主成分 (PC1)明显将缺钾处理与其他处理区分开,与对照相比,缺钾老叶离子组成变化为N (?3%)、P (+1%)、K (?71%)、Ca (+11%)、Mg (+39%)、B (+16%)、Mn (+11%)、Fe (+32%)、Cu (?7%)、Zn (+14%)、Mo (?63%);新叶中PC1明显将缺氮处理与其他处理区分开,缺氮新叶离子组成变化为N (?53%)、P (+8%)、K (+7%)、Ca (?14%)、Mg (+11%)、B (+55%)、Mn (+51%)、Fe (?14%)、Cu (?57%)、Zn (+4%)、Mo (?25%)。老叶和新叶中元素含量呈正相关的元素是N-Cu、N-Ca、Mg-Mn和Cu-Mo,呈负相关的是K-Zn。  【结论】  脐橙幼苗老叶对钾的短期缺乏反应最敏感,缺钾会显著降低老叶中K和Mo含量并增加Mg和Fe含量,而新叶对氮素的短期缺乏最敏感,缺氮显著降低新叶中N、Ca、Cu和Mo含量。短期缺少P、Ca和Mg对脐橙幼苗叶片中的养分含量影响较小。     

李营养累积、分布及叶片养分动态研究

基于保障生态和果品安全以及合理实施果园养分管理的前提,对大石早生李树体各部位营养元素积累、分布以及各营养元素的周年变化规律进行了分析.结果表明:①营养元素在各个器官的相对含量,除K、Zn在果实中含量最高外,N、P、Ca、Mg均以叶片中含量为最高,以叶片做营养诊断是适宜的.②大石早生李树体营养元素N、P、K、Ca、Mg、Fe、Zn的元素比值为10.00:1.26:6.42:12.57:2.46:1.87:0.14.⑧100 kg鲜果的养分吸收量分别为:N 772.47g,P74.25 g,K 730.33g,Ca874.16 g,Mg 169.82 g,Fe 66.05 g,Zn 7.53 g,N:P:K的比例为1.00:0.10:0.95.④N、P、K、Ca、Mg、Fe、Zn、Mn、Cu的含量随物侯期呈规律性变化.生长季初期,N、P、K、Zn、Cu的含量迅速下降,Fe、Mn、Ca、Mg呈逐渐上升的趋势;中期这9种元素总体变化幅度较小;后期Fe,Cu.N、P、K的含量呈下降趋势,Mn、Zn、Ca,Mg依然上升.本结果既丰富了国内李营养理论,同时又为制定合理的施肥措施及建立绿色优质果品科技示范基地提供了理论依据.     

Effect of wastewater irrigation on mineral com‐position of corn and sorghum plants in a pot experiment

Effect of wastewater irrigation was investigated on mineral composition of corn and sorghum plants in a pot experiment. The ranges for the concentration of different minerals in corn plants were 0.67–0.89% calcium (Ca), 0.38–0.58% magnesium (Mg), 0.09–1.29% sodium (Na), 0.81–1.87% nitrogen (N), 1.81–2.27% potassium (K), 0.12–0.16% phosphorus (P), 190–257 mg/kg iron (Fe), 3.5–5.6 mg/kg copper (Cu), 37.1–44.5 mg/kg manganese (Mn), 21.6–33.6 mg/kg zinc (Zn), 1.40–1.84 mg/kg molydbenum (Mo), 11.0–45.7 mg/kg lead (Pb), and 2.5–10.8 mg/kg nickel (Ni). Whereas for sorghum plants, the ranges were: 0.56–0.68% Ca, 0.19–0.32% Mg, 0.02–0.27% Na, 0.69–1.53% N, 1.40–1.89% K, 0.10–0.14% P, 190–320 mg/kg Fe, 3.8–6.0 mg/kg Cu, 29.2–37.6 mg/kg Mn, 21.1–29.9 mg/kg Zn, 2.2–3.7 mg/kg Mo, 12.3–59.0 mg/kg Pb, and 2.5–15.2 mg/kg Ni. Heavy metals such as cobalt (Co) and cadmium (Cd) were below detection limits at mg/kg levels. The concentrations of Ca, N, K, P, Cu, and Mn in corn plants were in the deficient range except for Mg, Fe, Zn, and Al. The concentrations of Ca, N, P, K, Cu, Mn, Mg, and Zn in sorghum plants were in the deficient range except for Fe and aluminum (Al). The analysis of regression indicated a strong interaction between Pb, Ni, Ca, and Fe in corn and sorghum plants. In conclusion, waste water irrigation did not increase mineral concentrations of either macro‐ and micro‐elements or heavy trace metals in corn and sorghum plants to hazardous limits according to the established standards and could be used safely for crop irrigation.     

Element interconnections in Lotus japonicus: A systematic study of the effects of element additions on different natural variants

Lotus japonicus was used to study the distribution and interconnections of 15 elements in plant tissues, including essential and non-essential elements: boron (B), sodium (Na), magnesium (Mg), potassium (K), calcium (Ca), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), strontium (Sr), molybdenum (Mo), cadmium (Cd) and cesium (Cs). Large amounts of B and Ca accumulated in plant leaves, while Fe, Na, Ni, As and Cd tended to mainly occur in the roots, and Mo was the only element to accumulate in the stems. The elemental compositions within plants were severely disturbed by treatment with toxic elements. Competition between element pairs in the same group (e.g. K and Cs; Ca and Sr) was not found. Iron, Cu and Zn accumulation were induced by Cd and Ni addition. When natural variants grew in a nutrition solution with subtoxic levels of As, Cd, Cs, Ni, Mo and Sr, intriguing relationships between the elements (such as Fe, As and K; Mg and Ni; Mn and Ca) were revealed using principal-component analysis. This study on the plant ionome offers detailed information of element interactions and indicates that chemically different elements might be closely linked in uptake or translocation systems.     

Use of the O Horizon of Forest Soils in Monitoring Metal Deposition in Latvia

The concentrations of Cu, Cd, Pb, Zn, V,Ni, Cr, Fe Ca, Mg and K were determined in the organicsoil layer (O horizon) of pine forests in Latvia. Theconcentrations were expressed on a mass, volume andsurface area basis. When concentrations were calculatedper unit mass of the O horizon, significant positivecorrelations between concentrations in the O horizon andPleurozium schreberi were achieved for mostelements (excepting Cr, Ca and K), and to lesser degreesfor Cu, Pb, Zn, V, Ni and Fe when calculated on a volumeor area basis. Non-rotated principal components analysisidentified a major soil factor related to bulk density(volume- and area-based concentrations). The main groupsof related elements defined by varimax-rotated PCAcomponents were similar for the mass- and volume-baseddata, and regions with elevated levels of these elementscould be related to local pollution sources, similar tothe patterns previously reported from surveys based onmoss.     

Bioelement content and biomass in scots pine: Effect of acidification and liming

Dry weights and bioelement contents in biomass of Scots pine (aboveground) were estimated on some differently treated plots from one acidification experiment in North Sweden. Dry weight estimates of Scots pine biomass showed relatively small differences between treatments. The content of N, P, K, Ca, Mg, Mn, and S showed significant differences in a number of cases. The amount of N in different crown components increased; fertilizer-N recovered in the biomass was up to 10% of that added (in total, the NPK-plots received 1260 kg N ha^?1). The concentration of other elements (P, K, Ca, Mg, Mn and S) showed some effect of the treatments, but was not as marked as that of N. Especially interesting is a decrease in the level of Mg in needles and shoots on the NPK-treated plots. The concentration of S was influenced by application of acid, but much more by NPK-fertilization throughout the period.     

Bioelement content and biomass in scots pine: Effect of acidification and liming

Dry weights and bioelement contents in biomass of Scots pine (aboveground) were estimated on some differently treated plots from one acidification experiment in North Sweden. Dry weight estimates of Scots pine biomass showed relatively small differences between treatments. The content of N, P, K, Ca, Mg, Mn, and S showed significant differences in a number of cases. The amount of N in different crown components increased; fertilizer-N recovered in the biomass was up to 10% of that added (in total, the NPK-plots received 1260 kg N ha^?1). The concentration of other elements (P, K, Ca, Mg, Mn and S) showed some effect of the treatments, but was not as marked as that of N. Especially interesting is a decrease in the level of Mg in needles and shoots on the NPK-treated plots. The concentration of S was influenced by application of acid, but much more by NPK-fertilization throughout the period.     

Plant tolerance to nickel toxicity: II nickel effects on influx and transport of mineral nutrients in four plant species

Nickel (Ni) is an essential micronutrient for higher plants but is toxic to plants at excess levels. Plant species differ extensively for mineral uptake and accumulation, and these differences often help explain plant tolerances to mineral toxicities/deficiencies. Solution culture experiments were conducted under controlled conditions to determine the effects of Ni on influx into roots (IN) and transport from roots to shoots (TR) of zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), calcium (Ca), magnesium (Mg), phosphorus (P), and sulfur (S) in white clover (Trifolium repens L.), cabbage (ßrassica oleracea van capitata L.), ryegrass (Lolium perenne L.), and maize (Zea mays L.). Nickel decreased both IN and TR of Zn, Cu, Ca, and Mg, but only TR of Fe and Mn in white clover. Both IN and TR of Cu, Fe, Mn, Mg, and S were markedly decreased by Ni >30 μM in cabbage, whereas IN and TR of P increased with Ni treatment. For ryegrass, TR of Cu, Fe, Mn, Ca, and Mg was decreased, but IN of these elements except Mg was not affected by Ni. The IN and TR of P and S were increased in ryegrass with increasing external Ni levels. Nickel inhibited IN of Cu, Ca, and Mg, and TR of Zn, Cu, Fe, Mn, Ca, and Mg in maize. Plant species differed in response to Ni relative to IN and TR of mineral nutrients. Plant tolerance to Ni toxicity was associated with the influence of Ni on IN and TR of Cu, Fe, and Mn in white clover and cabbage but not in maize and ryegrass.     

番茄对氮磷钾及中微量元素的吸收规律研究

通过田间试验研究了番茄生长过程中对氮、磷、钾及中微量元素的吸收分配规律.通过试验,测定番茄各个时期根系、茎秆、叶片、果实中氮、磷、钾、钙、镁、铁、锰、铜、锌的含量,旨在发现番茄各时期矿质元素的吸收规律.研究表明:随番茄生长发育的进行,氮、磷、钾及中微量元素在根、茎、叶中的分配率均呈降低的趋势,而果实中各元素分配率持续提...     

Etude par spectrometrie de masse a etincelles de la composition minerale de cuticules isolees de feuilles de poirier passe crassane

Abstract

The minerai content of enzymatically isolated pear leaf cuticles has been determined using a technique allowing a high sensitivity and a wide elemental coverage : the spark source mass spectrometry. About thirty elements have been detected, classified in different classes according to their content : N, K (major) Ca, Si, Al, Na (≥ 1 000 ppm) Fe, Cl, Mg (≥ 100 ppm) P, Cu, Zn, Ti, Ba, Mn, Ni, Co, Sr (≥ 10 ppm) B, Ag, Rb, Cr, Sn, V, Pb, Cd, U etc... (traces). These results are compared with analysis of entire pear leaves effected simultaneously and with those reported in literature concerning isolated tomato fruit cuticles. The problem of their validity for cuticles in situ, is discussed.     

Essential and toxic elements in seafood available in poland from different geographical regions

The concentrations of 15 elements (Cu, Fe, Mn, Zn, Co, Ni, Cr, Se, Cd, Pb, Hg, Ca, Na, K, and Mg) were determined in the edible parts of shellfish on sale in the local market in Gdańsk. The samples consisted of three groups--crustaceans, molluscs, and surimi--that are processed to different degrees. For the purposes of this analysis, they were dried, homogenized, and digested in an automatic microwave system. The samples were analyzed quantitatively for Cu, Zn, Fe, Mn, Co, Ni, Cr, Mg, Na, K, and Ca (F-AAS), Cd and Pb (GF-AAS), Se (HG-AAS), and Hg (CV-AAS). The elemental levels detected in shellfish were compared to those in cod, herring, pork, beef, chicken, and eggs. The recommended dietary allowance (RDA) of essential elements and the provisional tolerable weekly intake (PTWI) of toxic elements were estimated. With factor analysis of the data, taxonomically different groups of raw and processed shellfish could be distinguished.     

Seasonal dynamics of mineral nutrients by walnut tree reproductive organs

The dry weight accumulation per male and female flower as well as the concentration per gram of dry weight and the accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were determined in walnut tree (Juglans regia L.) catkins and female flowers at the stage of flower bud and during the flower development. Catkin emergence was accompanied by a very fast hydration of the tissues. After the catkin matured, the fresh and dry weights were reduced. The female flower development period was accompanied by the dry and fresh weight increase. Total N, P, K, Fe, Mn, Cu and Zn concentrations in catkin buds were detected at lower levels, Mg in equal levels, and Ca at higher levels as compared to the nutrient concentrations in young growing leaves. The estimated values of the ratio NCmfb/NCygl were: total N = 0.54, P = 0.83, K = 0.56, Ca = 1.5, Mg = 1.0, Fe = 0.46, Mn = 0.71, Cu = 0.85, and Zn = 0.60. Nutrient concentration in female flower buds was detected in almost equal levels with the exception of total N and Fe. The estimated values of the ratio: NCffb/NCygl were: total N = 0.57, P = 1.1, K = 1.17, Ca = 1.06, Mg = 0.9, Fe = 0.47, Mn = 1.0, Cu = 0.92, and Zn = 0.85. Total N, P, Mn, Cu, and Zn accumulations in the catkin were increased during the fast growing phase and decreased after catkin maturing. Potassium, Mg, and Fe accumulation continued to increase in the mature catkin. Calcium accumulation decreased at a very late mature catkin phase. Total N, P, and K accumulation rates during the catkin fast growing phase were higher than the dry weight accumulation rate. Calcium, Mg, Fe, Mn, Cu, and Zn accumulation rates at the same period were lower or equal to dry weight accumulation rates. In mature catkins, the total N, P, Mn, Cu, and Zn depletion rates were higher than the dry weight depletion rate. The continual increase of K, Ca, Mg, and Fe accumulation in mature catkin resulted in the increase of nutrients concentration also. Total N and P showed the highest remobilization values from mature catkin of 51.4% and 45%, respectively. Calcium, K, Mg, Cu, Mn, and Zn remobilization values estimated to be 22.1%, 7.5%, 3.2%, 45.3%, 33.4%, and 31.8%, respectively. Iron showed no remobilization at all. Nutrients remobilization from catkins as compared to the leaves had almost similar values for total N, Zn, and Cu, higher for P, Ca, and Mn, and lower for Mg, Fe, and K. Accumulation of all nutrients in female flowers increased after fertilization. The dry weight accumulation rate was higher than the nutrient accumulation rates.     

钙、 硼对常山胡柚叶片养分、 果实产量及品质的影响

【目的】研究叶片矿质营养元素含量的季节性变化,对探明植物体中营养元素的丰缺状况、 调控养分代谢、 提高果实产量和改善品质具有重要意义。本研究结合常山胡柚园土壤养分状况,通过连续4年施用钙肥和硼肥,研究钙、 硼对常山胡柚叶片矿质营养元素含量的季节变化、 果实产量及品质的影响。【方法】采用田间定位试验,以13年生枳砧常山胡柚为试验材料,设4个处理,1)CK(对照); 2)Ca(每株0.5 kg生石灰粉); 3)B(每株25 g 硼砂); 4)Ca+B(每株0.5 kg生石灰粉+ 25 g 硼砂)。于试验的第4年采集常山胡柚不同生长期当年生春梢叶片及成熟期果实样品,并对常山胡柚叶片矿质营养元素含量的季节变化、 果实品质进行分析。【结果】常山胡柚叶片各矿质养分在果实逐渐成熟过程中总体呈现先增后降的变化规律,其中叶片氮(N)、 钾(K)、 镁(Mg)和锌(Zn)在果实坐果期达到最大值,磷(P)在果实膨大前中期(8月份)到达最大值,钙(Ca)、 硼(B)、 铁(Fe)、 锰(Mn)和铜(Cu)在果实膨大后期(9月份)出现最高值。钙、 硼肥施用均可提高常山胡柚果实各发育时期叶片Ca、 B、 N、 K、 Fe、 Mn和Cu含量,但明显抑制叶片Zn的吸收,其中钙、 硼配施对成熟叶片(8~9月份)Ca含量存在显著正交互效应,但对提高叶片B含量无显著交互作用。施钙、 硼肥可不同程度提高常山胡柚2年平均产量,增产率达到1.8%~21.4%,其中各处理增产率顺序为Ca+B＞B≥Ca,且单施硼可显著提高2年累积产量,钙硼配施对单年产量、 2年平均产量均存在显著正交互效应。钙、 硼肥单施对果实品质无显著性影响,但钙硼配施可显著降低可滴定酸含量,显著提高固酸比。【结论】常山胡柚坐果期(4月份)为叶片N、 P、 K、 Mg和Zn吸收的关键时期,果实膨大期(8~9月份)为叶片Ca、 B、 Fe、 Mn和Cu吸收的重要时期。钙、 硼配施既可明显提高常山胡柚叶片中矿质营养元素含量(P和Zn除外),又能显著提高果实产量和品质。     

Calcium and L-histidine interaction on nutrients accumulation in three tomato cultivars under nickel stress

This study was carried out to evaluation of some nutrients accumulation including Ni (nickel), Fe (iron), Mg (magnesium), Cu (copper), Ca (calcium) as well as Ni translocation factor (TF) in three tomato cultivars grown hydroponically under treatments including L-histidine (His) and calcium chloride (CaCl₂) (300 µM) exposed to nickel (II) sulfate (NiSO₄) (150 and 300 µM) by ICP-OES (inductively coupled plasma atomic emission spectroscopy) analysis. Tomato cultivars included Cal-J N3, Early Urbana Y and. Results indicated that shoot Ni accumulation increased under Ni stress. Ca and His reduced root, shoot Ni content and Ni TF (translocation factor) under Ni stress in Petoearly CH cultivar. Ni stress also decreased root and shoot Ca, Fe, Mg and Cu while Ca and His improved the nutrients uptake, and inhibited Ni accumulation. Therefore, Ca and His alleviated adverse effects of Ni stress on nutrients in Petoearly CH cultivar. Beside, Ca and His interaction alleviate Ni stress by inhibition of Ni uptake and translocation as well as plant nutrition improvement in the tomato plants.     

Critical nutrient concentrations and antagonistic and synergistic relationships among the nutrients of NFT‐grown young tomato plants

Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn.     

Fluctuations of element concentrations during the growing season of Polytrichum formosum (Hedw.)

Fourteen elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Ni, Pb, Sr, Ti, and Zn) were quantitatively determined by AES/ICP in aboveground parts of the endohydric moss Polytrichum formosum (Hedw.) after sampling over regular intervals from 1985 to 1987. With the exception of K, Mg, and Zn all elements showed a large continuous fluctuation (> 30%) during the growing season. Four different patterns of seasonal variation were found: (1) large seasonal variations of element concentrations (～80%) with maximum concentrations in winter and lowest concentrations in the summer months (Al, Fe, Cr, Mg, Pb, and Ti), (2) smaller seasonal variations (～50%) with maximum concentrations in winter and lowest concentrations in summer (Ba, Ca, Cd, Cu, Sr), (3) slight seasonal variations (～30%) with maximum concentrations in the summer (K), and (4) slight seasonal changes (～30%) with maximum concentrations in the winter (Mg and Zn). The relative biological variance of element concentrations between 9 different stands of Polytrichum formosum decreases in the following sequence: Ti, Al, Pb, Fe, Cr, Ni, Ba, Ca, Cu, Cd, K, Mg, Sr, Zn. The relative biological variance of individual elements is generally lower than the variance in element concentrations caused by seasonal changes. Because of its high biological variance for most elements investigated (seasonal as well as between different stands of Polytrichum formosum) this moss should only be used as a passive bioindicator, if all other environmental parameters are standardized.     

Seasonal dynamics of mineral nutrients and carbohydrates by walnut tree leaves

The dry weight accumulation per leaf as well as the concentration per gram of dry weight and the accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were determined in walnut tree leaves (Juglans regia L.) during a complete life cycle. Additionally, the dynamics of plant nutrient concentration in leaf petiole sap and carbohydrate accumulation in leaves were studied in relation to the main life cycle events of the walnut tree. Total N, P, K, Cu, and Zn concentrations decreased, whereas that of Ca, Mg, and Mn increased during the season. Iron concentration fluctuated around a mean value. Total N, P, K, Mg, and Cu concentrations detected in younger mature leaves were at the sufficient level, whereas Ca, Fe, Mn, and Zn concentrations were at higher levels as compared to those previously reported. All the detected nutrient accumulations increased abruptly during leaf ontogeny and leaf maturation until a maximum level was attained in the younger mature leaves. Similarly, sucrose, glucose, and fructose accumulation were observed at the same period. The rates of total N, P, Cu, and Zn accumulation were lower than the rates of the observed dry matter accumulation and nutrient concentration dilution. Potassium and Mn accumulation rates were almost equal, whereas those for Ca and Mg were higher as compared to the dry matter accumulation rate. The fast embryo growing phase resulted in a considerable decrease in dry weight, total N, P, K, Cu, Zn, and carbohydrate accumulation, and to a lesser degree in Ca, Mg, and Mn accumulation. Nutrient accumulation reduction in leaves by the influence of the growing fruits were estimated to be: total N 52%, K 48%, P 29.5%, Mg 16.3%, Ca 15%, Fe 51.2%, Cu 55.2%, Zn 37.3%, and Mn 5.4% of the maximum nutrient value of the younger mature leaves. Old leaves preserved nutrients before leaf fall as follows: total N 25.4%, P 45%, K 31%, Ca 74.8%, Mg 76.5%, Mn 89.2%, Fe and Zn 50%, and Cu 37%. Nutrient remobilization from the senescing old leaves before leaf fall were: total N 22.6%, P 25.5%, K 21%, Ca 10.2%, Mg 7%, Fe 3.2%, Mn 5.4%, Cu 8%, and Zn 13.3% of the maximum value in the younger mature leaves. In early spring, the absorption rates of N, P, and Ca were low while those of Mg, Fe, Mn, Cu, and Zn were high. During the fast growing pollen phase, the N, P, Fe, Mn, Cu, and Zn concentrations were reduced. Calcium concentration is supposed to be more affected by the rate of transpiration rather than during the growing of embryo. Calcium and Mg concentrations in the sap were negatively correlated. The detected K concentration level in the sap was as high as 33 to 50 times that of soluble N, 12 to 21 times to that of P, 5 times to that of Ca, and 10 to 20 times to that of Mg. The first maximum of starch accumulation in mature leaves was observed during the slow growing embryo phase and a second one after fruit ripening. Old senescing leaves showed an extensive carbohydrate depletion before leaf fall.     

Seasonal Variation in Nutrient Status of Foxglove Leaves

The seasonal variation of mineral elements and the relationships among them were studied in natural populations of foxglove (Digitalis obscura). Young and mature leaves were collected in 10 different populations and on four sample dates (May, July, October, and February). Leaf mineral elements [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu)] were determined. The highest concentrations of N, P, and K in young leaf were recorded in May, followed by a decrease in the other months, while in contrast Ca and Fe showed the lowest concentration in May. Mature leaves showed differential seasonal behavior. Besides seasonal variations, significant fluctuations of N/P and Ca/Mg ratios were observed in young leaves. Strong positive correlations existed among N, P and K, while negative correlations were found between Ca and N, P, or K.