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1.
Summary This paper describes a factorial experiment which was designed to elucidate the effect of total iron supply and rate of iron supply on the yield of tomato plants. Information was also obtained on the effect of iron supply and leaf age on the concentration of a number of nutrient elements in the leaf tissue.Increasing the total iron supply increases the yield, and the iron concentration in the leaves, while the manganese, phosphorus, sodium, calcium and magnesium decrease in concentration. The young leaves have a lower concentration of iron, manganese, potassium, sodium, calcium and magnesium than the older leaves, while the reverse is true of nitrogen and phosphorus. A slow rate of iron supply decreases the yield and sodium concentration in the leaves but increases the manganese and phosphorus concentrations.Interaction between total iron supply and leaf position affects the manganese, potassium, calcium and magnesium concentrations in the leaves, while the interaction between total-iron level and rate of iron supply affects the phosphorus and calcium concentration in the leaves.  相似文献   

2.
Material from four fertilizer trials on barley in Hampshire was analysed with the principal purpose of comparing the extent to which the potassium content of different plant organs was diagnostic of potassium deficiency. Samples of older leaf blades and sheaths, young leaves, stems and ears were gathered at the time of ear emergence from each of the 108 plots, and analysed spectrographically for calcium, iron, magnesium, manganese, potassium and sodium.
Differences in composition between plants from the different sites were proportionately greater in the older leaf blades than in the other organs for calcium, the young leaves for manganese and sodium, and the older leaf blades and sheaths for potassium. Differences in sodium and manganese content at the different sites appeared to be related to the differences in potassium status.
Applications of muriate of potash increased the potassium content of all organs except the ears, and decreased the content of magnesium, manganese and sodium, and of iron at one site. The effect of potassium supply on manganese and sodium content was most marked in the young leaves. The proportional increases observed in potassium content as a result of application of muriate of potash were similar at all four sites, in spite of the fact that responses in growth and yield differed greatly.
As between the four sites, the responses to muriate of potash observed in the yields of grain are significantly correlated with the potassium content of the older leaf blades and the stems, and the following tentative limiting values are put forward, above which no increase in grain yield as a result of potassic manuring may be expected:
(a) in the older leaf blades at the time of ear emergence 0.92% potassium in dry matter, (b) in the stems at the time of ear emergence 1–01 % potassium in dry matter.  相似文献   

3.
The monthly deposition of total nitrogen, phosphorus, potassium, calcium and magnesium via canopy throughfall, and various components of the litterfall was measured for 31 months under mature Quercus douglasii and in the bulk precipitation in the surrounding open grassland. Seasonal patterns of nutrient concentration in leaf litter, throughfall, and precipitation were also measured. Total annual subcanopy deposition exceeded open precipitation deposition by approximately 45–60x for nitrogen, 5–15x for phosphorus, 30–35x for potassium, 25–35x for calcium, and 5–10x for magnesium. Total annual subcanopy deposition was low in comparison to other oak woodland sites reported in the literature. Throughfall and leaf litter were the primary sources of nutrients and thus determined the seasonal peaks of nutrient deposition. The first autumn rains and leaf fall were associated with one peak in nutrient deposition, and throughfall during early spring leaf emergence was associated with a second peak in potassium, magnesium and phosphorus. Non-leaf plant litter (excluding acorns) provided approximately 15–35% of most nutrients, with twigs and bark depositing over 12% of the annual calcium flux in 1987–1988, and flower litter depositing over 8% of the annual nitrogen flux in 1986–1987. Acorns had high concentrations of phosphorus and nitrogen and during the mast season of 1987–1988 they contained a large proportion of the total subcanopy annual flux of these elements. With acorns excluded, total annual nutrient deposition was similar between years, but timing of nutrient deposition differed. Late summer leaf fall associated with drought, variation in precipitation, and variation in deposition of non-leaf parts were associated with seasonal differences in nutrient deposition between years.  相似文献   

4.
Y. B. Ho 《Hydrobiologia》1981,85(3):227-237
Monthly levels of nitrogen, phosphorus, potassium, sodium, calcium, magnesium and iron in the organs (root, rhizome, stem, leaf and panicle) of Phragmites australis were determined from March to November, 1975 in Forfar Loch (polytrophic), Balgavies Loch (eutrophic) and Loch of the Lowes (mesotrophic), Scotland. Generally no consistent seasonal changes in the mineral levels were detected for the root, rhizome and panicle. For the stem and leaf, the levels of nitrogen, phosphorus, potassium, calcium and magnesium rose to a peak before declining for the rest of the season. Consistently higher levels of tissue nitrogen, phosphorus, potassium and calcium were found in the Forfar plants over those of Balgavies and Lowes, reflecting the very eutrophic condition in Forfar Loch. The mineral compositions in the reeds in the present study were compared with similar studies in other areas.  相似文献   

5.
外源施钙对盐胁迫下花生营养元素吸收与分配的影响   总被引:2,自引:0,他引:2  
为解决盐碱地花生养分吸收不畅及分配受阻等问题,研究外源施钙对盐胁迫下花生氮、磷、钾、钙、镁吸收积累、分配特性和产量的影响,为盐碱地花生生产合理、高效施肥提供理论依据.以‘花育25号’为材料,在0.3%盐胁迫浓度下,设置4个Ca浓度梯度[T1(0)、T2(75)、T3(150)和T4(225) kg·hm-2 CaO]进行盆栽试验.结果表明: 花生植株内养分含量依次为氮>钾>钙>磷>镁,苗期植株对氮和钙素的吸收中心均在叶片,磷、钾、镁的吸收中心为茎,苗期近一半的营养积累分配在各元素相应的生长中心.成熟期氮、磷、钾吸收中心转移到荚果中,尤以氮、磷在籽仁中的积累量居多,达72.3%~78.9%;钙、镁的吸收中心仍为叶片和茎,其分配比例分别为49.8%、32.6%.盐胁迫明显抑制花生植株各器官对氮、磷、钾、钙和镁各元素的吸收积累与分配,尤以对叶片和籽仁中氮素积累的抑制较为显著,但盐胁迫对荚果中镁的积累有促进作用.外源钙对盐胁迫下花生植株各器官氮、磷、钙和镁的吸收累积有明显的促进作用,尤其对籽仁中磷素积累的调节最为显著,其在籽仁中的积累量提高50%以上.适宜的钙施用量可显著促进盐胁迫下花生养分吸收积累量,提高花生成熟期荚果中氮、磷、钾的分配比,最终提高产量.综合各养分吸收、积累分配和产量结果,在0.3%盐胁迫条件下钙肥适宜施用量为150 kg·hm-2 CaO.  相似文献   

6.
Summary Decreases in the concentrations of nitrogen, phosphorus, potassium, calcium and magnesium, in the shoots of wheat seedlings soon after the start of waterlogging were mainly attributed to an inhibition of ion uptake and transport by roots in the oxygen deficient soil. There was a small net accumulation of nitrogen, phosphorus and potassium by the aerial tissues, principally the tillers rather than the main shoot. By contrast, calcium and magnesium accumulated in both tillers and main shoot. With waterlogging, nitrogen, phosphorus and potassium were translocated from the older leaves to the younger growing leaves, and in the case of nitrogen this was associated with the onset of premature senescence. Calcium and magnesium were not translocated from the older leaves, the younger leaves acquiring these cations from the waterlogged soil. The promotion of leaf senescence by waterlogging was counteracted by applications of nitrate or ammonium to the soil surface, or by spraying the shoots with solutions of urea, but the beneficial effects on shoot growth were small.The role of mineral nutrition in relation to waterlogging damage to young cereal plants is discussed.  相似文献   

7.
以种植于干热河谷区的赤桉(Eucalyptus camaldulensis Dehnh.)幼龄林、中龄林和成熟林为研究对象,分析了赤桉鲜叶和凋落叶中养分(包括N、P、K、Ca、Mg和Na)的含量和化学计量比,并计算各养分的再吸收率;在此基础上,对鲜叶和凋落叶中各养分的含量与再吸收率进行线性回归分析.结果表明:成熟林赤桉鲜叶和凋落叶的有机碳、全氮、全磷、全钾和全钠含量总体上高于幼龄林,而全钙和全镁含量则低于幼龄林;且鲜叶中的全氮、全磷、全钾、全钠和全镁含量总体上高于凋落叶,而有机碳和全钙含量则低于凋落叶.成熟林赤桉鲜叶和凋落叶的C:N比、鲜叶的N:P比和N:K比以及凋落叶的K:P比和Ca:Mg比均低于幼龄林,但其鲜叶的K:P比和Ca:Mg比及凋落叶的N:P比和N:K比则高于幼龄林;且不同林龄鲜叶的C:N比、K:P比和Ca:Mg比均低于凋落叶.各林龄赤桉叶的Ca再吸收率及幼龄林和中龄林叶的Na再吸收率均为负值,而其余养分的再吸收率均为正值;随林龄增长,N、K和Mg的再吸收率先升高后降低,而P、Ca和Na的再吸收率却先降低后升高;总体上看,赤桉叶中各养分的再吸收率从高到低依次为P、N、K、Mg、Na、Ca.线性回归分析结果表明:赤桉鲜叶的全钾和全钠含量分别与K和Na再吸收率呈极显著正相关(P<001),全钙含量与Ca再吸收率呈显著正相关(P<005);而凋落叶的全氮含量与N再吸收率呈极显著负相关,全镁含量与Mg再吸收率呈显著负相关.综合分析结果显示:林龄对赤桉叶的养分含量和再吸收率有明显影响,其保存养分的能力随林龄增长呈现先增强后减弱的趋势.  相似文献   

8.
After a fire in a phryganic ecosystem, the nutrient losses in above-ground plant biomass, in nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were quantitatively different. The most important is that of nitrogen (96%), followed by magnesium (59%), potassium (54%) and calcium (36%) while phosphorus content remained constant. Removal of these elements took place through fire's smoke.  相似文献   

9.
Proximate (live mass, water, lipid, ash, non-fat organic), caloric, nitrogen, and mineral (sodium, potassium, calcium, magnesium, and iron) concentrations and total body content of individuals of 24 species of Neotropical and Paleotropical bats were determined. Mass-related, concentration patterns were found for all measured variables, except iron. Concentrations increase with size for nitrogen, calcium, and magnesium but are concave, opening upward, for sodium and potassium. These last two elements reach minimal concentrations in bats weighing about 22 and 28 g dry mass, respectively. Total body content of nitrogen and minerals was compared with amounts in similar-sized birds and tetrapodal mammals.  相似文献   

10.
Stocking , C. Ralph , and Alpaslan Ongun . (U. California, Davis.) The intracellular distribution of some metallic elements in leaves. Amer. Jour. Bot. 49(3): 284–289. Illus. 1962.—A comparison of the potassium, sodium, calcium, magnesium, and nitrogen levels of chloroplasts isolated in an aqueous sucrose medium and by the nonaqueous method reveals that large amounts of these elements are lost from the plastids during their isolation in sucrose solution. Nonaqueously isolated chloroplasts of bean and tobacco leaves contained over 40% of the total leaf potassium, magnesium, and calcium. High levels of nitrogen up to 70% of the total leaf nitrogen were found associated with nonaqueously isolated chloroplasts. As much as 40–50% of this nitrogen is lost when chloroplasts are isolated in a sucrose solution. Electron photomicrographs of nonaqueously isolated chloroplasts reveal only a partial disruption of the internal structure and a loss of the plastid membrane during isolation.  相似文献   

11.
为探讨果园土壤矿质元素与叶片营养水平的相互关系,于巴仁杏盛果期采集南疆阿克陶县巴仁杏果园的壤土和沙土土样,以及植株叶片,测定土壤与叶片矿质元素质量分数,结果表明,该地区2种类型土壤巴仁杏果园叶片全氮质量分数均偏低,沙土果园叶片镁质量分数偏低。不同土壤类型果园叶片全氮、钾、钙、镁质量分数差异显著。该地区果园土壤养分整体较低,其中,土壤有机质、氮、磷、锌、锰、铜质量分数均偏低,此外不同矿质元素在不同土层的分布规律因土壤类型不同而各有差异。2种土壤类型果园的土壤有机质质量分数与叶片磷质量分数均呈正相关,叶片其他矿质元素质量分数与土壤有机质质量分数的相关性与土壤类型有关;土壤矿质元素与叶片相应矿物质元素的相关性因土壤质地不同而存在较大差异。因此,在巴仁杏果园的土肥管理中应增施有机质及氮、磷、锌、锰、铜、硼等矿质元素。此外,对不同土壤类型果园的管理应根据果园土壤类型进行针对性施肥。  相似文献   

12.
Summary Manure from finishing pigs fed diets with and without a growth stimulating level of added copper (250 ppm in 1972, 370 ppm in 1973 and 300 ppm in 1974) was incorporated into a Groseclose silt loam at the rate of 15.5, 12.9 and 15.7 metric tons of dry matter per hectare, respectively, for 1972, 1973 and 1974. A third treatment was no manure. The manure was applied between rows when corn was about 10 cm tall and worked into the surface 10 cm of the soil with a rotary tiller. The average composition of the manure for the three years on a dry basis was 3.6 per cent nitrogen, 2.87 per cent calcium, 0.93 per cent magnesium, 2.22 per cent phosphorus, 1.30 per cent potassium, 648 ppm zinc, 2191 ppm iron. The copper content was 73 ppm for control manure and 1719 ppm for high copper manure. The copper content in the upper 10 cm of the soil was significantly increased each year when high copper manure was applied. During one growing season, copper did not appear to move down, however, plowing after the first year increased the copper level in the 10–20 cm depth with a small increase in the 20–30 cm depth. Potassium, zinc, phosphorus, calcium and magnesium levels of the soil were increased when manure was applied. There was a small increase in the copper content of the maize ear leaf (average of one ppm per year) when manure from pigs fed diets containing high copper was applied. Copper in the washed roots of the mature maize plants was doubled (5.6 vs 11.2 ppm) when the high copper manure was added. The copper content of grain from plants grown on soil receiving high copper manure was not different from that of grain from soil receiving no manure. The zinc, potassium and phosphorus contents of the maize ear leaf were increased a small amount when both control and high copper manure were applied with the effect of potassium and phosphorus carrying over to the grain. The iron and calcium contents of the ear leaf were not affected by application of manure, but there was a decrease in calcium content of the grain from the application of control and high copper manure. re]19750305Department of Animal ScienceDepartment of AgronomyDepartment of Statistics  相似文献   

13.
The results are given of chemical analyses of leaves collectedover a period of two years from cocoa trees in a field trialreceiving fertilizer, shade, and irrigation treatments. Thegreatest variation in concentration of nutrients in the leaveswas due to the time of year the leaves were collected. The lowestconcentrations of nitrogen, phosphorus, and potassium were foundin the leaves collected during the peak of the main season harvest.The highest levels of these elements were found in leaves collectednear the end or a few weeks after the end of the main harvest.The levels of calcium in the leaves were just opposite, withthe highest levels coinciding with harvest and the lowest levelsoccurring just after the harvest period. The levels of magnesiumshowed no marked variations between seasons. Shade increased the levels of nitrogen, phosphorus, and potassium,and decreased the levels of calcium in the leaves. Fertilizerincreased the levels of nitrogen, phosphorus, calcium, and magnesium,and decreased the level of potassium in the leaves. The effectof irrigation was small, but it decreased the levels of nitrogen,potassium, calcium, and magnesium in the leaves. The levels of nitrogen, phosphorus, and potassium in the leavesover the 21 harvesting times were found to be positively correlatedwith each other, and all three were negatively correlated withthe levels of calcium in the leaves over the same period. Noneof the levels of these four elements was significantly correlatedwith the levels of magnesium in the leaves over the period.  相似文献   

14.
Effects of silicon on the chemical composition of rice plants   总被引:3,自引:2,他引:1  
Summary Rice plants were grown in nutrient culture solutions. Silicon was supplied to these plants at different rates. The plant samples of early vegetative, vegetative and flowering stages were analysed for nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese, silicon, protein and carbohydrate contents. The application of silicon generally decreased the nitrogen, protein and potassium content of rice plants. Its application also decreased the iron and manganese contents. The use of silicon resulted in an increase in phosphorus, calcium, magnesium, silicon and carbohydrate contents of rice plants.Reader and Head of the Department of Soil Science, University of Dacca, Dacca, East Pakistan.  相似文献   

15.
以2年生杜鹃(Rhododendron simsii)苗为研究对象,采用J1(杜鹃花类菌根真菌混合接菌)、J2(杜鹃花类菌根真菌和马尾松外生菌混合接菌)、J3(不接菌,对照)等3种接菌组合与不同氮磷钾施肥组合研究菌根真菌与氮磷钾肥对杜鹃苗生长及养分吸收的影响。结果表明,杜鹃幼苗的生长指标和氮磷钾含量总体表现为接菌处理优于不接菌处理,J2处理下施用尿素1.1 g·株-1、钙镁磷1 g·株-1、氯化钾0.7 g·株-1对杜鹃苗生长及氮磷钾含量积累的促进作用最为明显。数据表明,J2处理促进N向叶积累,促进K向茎叶积累,促进P向根茎积累;J1处理促进N和P向根茎积累,促进K向茎叶积累。  相似文献   

16.
Summary A declining Picea abies (L.) Karst. stand produced as much foliage and branches as a healthy stand but less stemwood at a similar leaf area index and climate. Nutrient analyses revealed that most biomass components at the declining site had lower concentrations of calcium and magnesium, but similar nitrogen and potassium (except for lower potassium in younger needles) and higher phosphorus, manganese and aluminum than the respective components at the healthy site. Comparison of these data with the results from studies on the nutrition and growth of P. abies seedlings (Ingestad 1959) led to the conclusion that the healthy stand is in a balanced nutritional state, while trees at the declining stand have only 56% of the foliar magnesium concentration required to permit growth at a rate which could be achieved at their nitrogen status. It appears that acidic deposition, which involves an input of nitrogen and a leaching of cations from the soil, causes an imbalance in the availability of nitrogen and magnesium. Growth is eventually reduced as magnesium becomes limiting.  相似文献   

17.
Summary Buckwheat was grown in media in which the supply of nitrate and potassium was varied. The relation between nitrate assimilation and the carboxylate content of the plant was examined.In full supply of nitrate total carboxylate came from and was equivalent to the assimilated nitrate. Only when this nutrient was depleted, bicarbonate was absorbed and assimilated as the alternative source which caused carboxylate to accumulate in excess of the deficient level of organic nitrogen.Shortage of potassium had no effect on the level of carboxylate because increased uptake of calcium and magnesium replaced the missing potassium.  相似文献   

18.
Summary Two experiments on cacao seedlings grown in sand culture are described, the first of which was concerned with variations in the levels of nitrogen, phosphorus, potassium, calcium, magnesium and sulfur (the macronutrient experiment) and the second dealing with variations in the levels of iron, copper, zinc, boron, manganese, and molybdenum (the micronutrient experiment).Many of the deficiency symptoms obtained were similar to those reported in the literature and they have not been described again. However, additional information is provided for symptoms of phosphorus, potassium, calcium, iron, manganese, copper, boron, and molybdenum deficiencies.The effects of all treatments on the dry weights of leaves, stems, and roots are presented. The effects of the macronutrient treatments on the levels of nitrogen, phosphorus, potassium, calcium, and magnesium in the leaves of eight month old plants and the effects of micronutrient treatments on the levels of nitrogen, phosphorus, potassium, calcium, magnesium, iron, manganese, copper, zinc, boron, molybdenum, sodium, and aluminium in the leaves of eleven-month-old plants are presented and discussed.  相似文献   

19.
湖南烟区土壤交换性钙、镁含量及对烤烟品质的影响   总被引:28,自引:0,他引:28  
分析了湖南烟区主要土壤类型交换性钙、镁元素含量状况及其对烟叶品质的影响,结果表明:(1)土壤交换性钙、镁含量在不同土壤类型间存在显著性差异,交换性钙含量平均为8.87cmol/kg,以红壤含量最高;交换性镁含量平均为1.16cmol/kg,以黄棕壤含量最高;交换性钙镁比值大小依次为:红壤(11.74)>水稻土(10.25)>黄壤(6.84)>黄棕壤(6.14),在烟叶实际生产中,应重视镁肥在红壤和水稻土中的施用;(2)烟叶钙含量偏高(21.93g/kg±4.37g/kg),烟叶镁含量偏低(2.52g/kg±1.26g/kg),两者均存在广泛的变异性;(3)整体来看,烟叶钙含量随土壤中交换性钙含量的升高和镁含量的降低而显著升高;烟叶镁含量随土壤交换性镁含量的升高而升高,与土壤交换性钙含量的相关性不显著;(4)典型相关分析表明,土壤中交换性镁含量的降低可能引起烟叶钾含量的提高,从而使得烟叶钾素和镁素含量达到较好的平衡;(5)土壤交换性钙、镁含量与烟叶其它化学成分指标的相关分析表明,土壤交换性钙有利于烟株对硼和氯素的吸收,对氮、锌和锰素的吸收则有显著的抑制作用;而土壤交换性镁有利于烟叶总糖、硼素和锰素的积累,对氮、磷、铁和锌素的吸收具有显著的抑制作用。  相似文献   

20.
森林生态系统中凋落物养分含量通常具有明显的时空异质性,为探究喀斯特常绿落叶阔叶混交林凋落叶养分含量的时空分布特征及其影响因素,以广西木论喀斯特常绿落叶阔叶混交林25hm2动态监测样地内151个凋落物收集器所收集的凋落叶为研究对象,选取连续12个月的凋落叶进行元素含量分析。结果显示:该森林群落凋落叶元素含量大小顺序为碳(C)>钙(Ca)>氮(N)>镁(Mg)>钾(K)>硫(S)>磷(P),分别介于471.85-496.33、20.27-28.29、17.34-23.10、2.79-5.49、1.80-4.38、1.82-2.22、0.96-1.21g/kg之间,呈现高Ca、Mg,低P、K的分布规律,并且随时间出现明显波动,其中C、N、P、S和Ca元素均在4月出现较大值,而K、Mg则在1月出现峰值。生物因子在5m和10m邻域范围内对凋落叶含量的影响基本一致,但10m尺度上地形因子和土壤因子对凋落叶元素含量的影响更为明显。10m邻域范围内生物和非生物因子对凋落叶P元素的随机森林累积解释率最高,达80.27%,C元素累积解释率最低,仅10.49%,其中海拔和坡度对凋落叶C、N、P、S、K、Ca和Mg含量均有强烈影响,岩石出露率和土壤铁(Fe)含量也会在一定程度上对凋落叶元素含量产生较大影响。综上所述,喀斯特常绿落叶阔叶混交林不同月际间凋落叶养分含量存在显著差异,10m尺度上海拔和坡度是凋落叶养分含量产生空间变异的主要原因。  相似文献   

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