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1.
小叶杨吸收利用NH4—N和NO3—N的研究 总被引：2，自引：0，他引：2
采用植物稳态营养研究的水培方法,研究了小叶杨幼苗在铵态N、硝态N及混合N源条件下的生长及对各大量元素的吸收。结果表明,小叶杨幼苗在纯铵态N和纯硝态N中的生长效果与混合N源相近,纯铵态N稍优。铵态N营养有利于对P、S等阴离子的吸收;不利于吸收K、Ca、Mg等阳离子。硝态N营养与此相反。 相似文献
2.
本研究旨在探讨不同铵硝态氮配比对针阔混交林中木荷和杉木幼苗生长的影响。通过测定光合特性、幼苗生长和生物量等指标,对两种树种在不同N素形态和配比下的响应进行了评估。研究结果显示,不同树种对铵硝态氮的响应存在差异。对于杉木而言,适量增施铵态氮可促进光合作用和地上部生长,但过高的铵态N浓度可能导致根冠比降低。而木荷则对较高硝态N浓度的处理有利于光合作用和地上部生长。因此,最佳的铵硝态氮配比可能因树种而异。在实际N施肥中,应考虑土壤中N素含量和比例,以制定合理的施肥策略。 相似文献
3.
利用5种丛枝菌根真菌,在不同肥态、肥力水平下对大青杨实生苗进行接种。结果表明:5种真菌都与大青杨形成了菌根,在不施肥情况下Glomusintraradices、G mosseae、G versiforme3个菌种的苗木在苗高、地径、总干生物量上都与对照表现出差异极显著,与菌根侵染率呈正相关。丛枝菌根能增加苗木对难溶性P肥的吸收和利用,特别是G sinuosa与施过磷酸钙(Ca(H2PO4)2·H2O)在有效成分(P2O5)含量0 06g·kg-1土水平下的组合对苗木有良好的促生效果,生物量积累是对照处理的3 58倍;使用G mosseae或G intraradices与施可溶性P肥磷酸氢二钾(K2HPO4),在有效成分(P2O5)含量0 03g·kg-1土水平下的组合时对苗木的促生效果达到最佳,但随着可溶性P浓度增加,丛枝菌根对苗木生物量的积累却有抑制作用;丛枝菌根同样促进苗木对硝态N和铵态N的吸收、利用,G ver -)含量0 08g·kg-1土水平下和G mosseae、siforme、G intraradices与施硝酸钾(KNO3)在有效成分(NO3 )含量0 08g·kg-1土水平下,对苗木都有良G intraradices与施硫酸铵((NH4)2SO4)在有效成分(NH4好的促生效果,总干生物量是对照处理的2 91、2 56和2 70、2 40倍;试验结果同时也表明,根际营养状况是决定菌根侵染率的重要因素之一。 相似文献
4.
《经济林研究》2021,39(3)
【目的】筛选出使叶用银杏高产优质的最佳硝铵配比。【方法】以2年生半同胞家系银杏苗为研究对象,设置5种硝铵比(0∶100、25∶75、50∶50、75∶25、100∶0),每盆总氮含量2 g,以不施氮肥为对照(CK),研究了不同硝铵配比对银杏苗木生长、叶生物量、叶片叶绿素含量、叶片可溶性糖含量、叶片可溶性蛋白含量、叶片NPK含量、叶片总黄酮含量及其经济产量、叶片萜内酯含量及其经济产量的影响。【结果】各硝铵配比处理促进了银杏苗的生长,提高了叶片叶绿素、可溶性蛋白、N、P、K的含量,同时提高了叶产量和总黄酮、萜内酯的经济产量。高比例的硝铵配比(75∶25)和单施硝铵(0∶100、100∶0)有利于总黄酮的积累,低比例的硝铵配比(25∶75)不利于总黄酮的积累,硝铵配比施肥不利于萜内酯的积累。单株叶产量与苗高相对生长量、地径相对生长量、单叶干质量、叶片可溶性糖含量、叶片可溶性蛋白含量、叶片N含量、叶片P含量、叶片K含量、总黄酮经济产量显著或极显著正相关,叶片总黄酮含量与总黄酮经济产量显著正相关,叶片萜内酯含量与单叶面积极显著负相关,单株黄酮经济产量与叶片可溶性糖含量、叶片可溶性蛋白含量、叶片N含量、叶片P含量、叶片K含量、叶生物量、总黄酮含量显著或极显著正相关,单株萜内酯经济产量与比叶干质量、叶片总叶绿素含量、叶片可溶性蛋白含量、叶片N含量、总黄酮经济产量显著或极显著正相关。基于主成分分析法,进行各处理肥效的综合评价,硝铵配比75∶25处理的综合得分最高。【结论】高比例的硝铵配比能有效促进银杏的生长发育,提高叶品质,单施硝态氮的效果优于单施铵态氮,其中硝铵配比75∶25是促进银杏苗的生长和提高叶品质效果最佳的配比。 相似文献
5.
《陕西林业科技》1974,(5)
硝态氮和铵态氮对湿地松苗生长和光合作用的不同影响——Driessche R. vanden. Different effects of nitrate and ammonium forms of nitrogen on growth and photosynthesis of slashpine seedlings. 《Anstral. Forest》, 1973, 36 №2, 125—137(英文) 在生长试验的各种处理中,研究Ca(NO_3)_2和(NH_4)_2SO_4溶液对湿地松(Pinuselliottii)苗生长和光合作用的影响。结苗子追6次肥,间隔一星期,每次270公斤/公顷,施铵态氮的比硝态氮的生长量大。在pH值5.5—7.0的范围内,施铵态氮的苗子生长量大,对照的生长量小。在pH值小于5.0的情况下,施铵态氮的比施硝态氮的生长量小;在pH值大于8.0的情况下,对照的生长大于试验的。实际上不同氮态的差别没有 相似文献
6.
应用PLFA方法分析氮沉降对土壤微生物群落结构的影响 总被引：4，自引：0，他引：4
【目的】土壤微生物是土壤生态系统变化的敏感指标。本研究选择磷脂脂肪酸法( PLFA)分析微生物群落结构的变化,可以更准确地了解短期氮沉降对土壤生态系统的影响,从而预测氮沉降后土壤性质及植物生长的变化趋势,为氮饱和条件下人工林的可持续经营提供微生物参数和指标,对氮沉降的即时调控和实时治理具有指导意义。【方法】2013年5月,在江西省分宜县山下林场约1 hm2的杉木幼龄林中建立30个1 m ×1 m 的样方,在30个样方中进行5种氮沉降量[N0(对照)、N1(20 kg·hm －2a －1)、N2(40 kg·hm －2a －1)、N3(60 kg·hm －2a －1)、N4(80 kg·hm －2a －1)]和2种氮形态(NH4+-N,I和 NO3－-N,II)的模拟沉降试验,沉降1年后用土钻进行土壤样品采集。磷脂脂肪酸提取方法为氢氧化钾－甲醇溶液甲酯化法,以十九烷酸为内标,采用 Agilent 6850N 测定,用Sherlock MIS4.5系统分析PLFA图谱,脂肪酸含量换算成每克干土中的含量( nmol)后进行分析。【结果】本研究共检测到PLFAs 72种,其中特征脂肪酸36种。分析特征脂肪酸种类和含量可知：各处理中土壤微生物群落均以原核微生物为主,不同氮处理样地中以磷脂脂肪酸总量表征的土壤微生物生物量范围20～44 nmol·g －1。沉降铵态氮时,土壤中 PLFA总量、革兰氏阳性菌、革兰氏阴性菌脂肪酸含量均高于对照样地,细菌、真菌、放线菌和原生动物的脂肪酸含量变化趋势相同,均为随着氮沉降量的增加先升高再降低最后再升高,NH4+-N N4处理土壤微生物 PLFAs的数量最多,NH4+-N N2处理土壤微生物 PLFAs的丰度值和多样性值最高;沉降硝态氮时,土壤中 PLFA 总量、革兰氏阳性菌和革兰氏阴性菌 PLFAs量随着硝态氮浓度的增加呈现出先增加后减少的趋势,在 NO3－-N N2处理达到最大值。细菌和放线菌的标记脂肪酸含量变化趋势相同。NO3－-N N2处理微生物脂肪酸量最多,NO3－-N N4浓度下微生物 PLFAs多样性值最高。根据典型性相关分析,得出铵态氮对土壤中细菌和放线菌含量影响较为显著,土壤中硝态氮和含水量对细菌含量影响较为显著。【结论】当氮沉降量小于80 kg·hm －2 a －1时,铵氮和硝态氮处理均促进了微生物的生长,但增长幅度不同。铵态氮的最高氮处理和硝态氮的中氮处理,更有利于土壤微生物总量的增长,铵态氮的中氮处理和硝态氮的最高氮处理,更有利于土壤微生物多样性的增加。铵态氮对土壤中细菌和放线菌含量影响较为显著,土壤中硝态氮和含水量对细菌含量影响较为显著。 相似文献
7.
《中南林业科技大学学报(自然科学版)》2016,(7)
以1年生油茶嫁接苗为研究对象,通过施肥试验,研究不同氨基酸态氮对油茶苗木生长的影响。结果表明:甘氨酸作为氮源能够促进油茶嫁接苗苗高、地径、生物量的增长,随施氮水平提高,苗高、地径、植株鲜重与干物重均随之增加,但浓度超过3 mmol/L后,促进作用有所减弱。等氮条件下,不同氮源对油茶各生长和生理指标的影响显著不同,其中甘氨酸、赖氨酸和丙氨酸对促进油茶嫁接苗苗高、地径和生物量的增长效果最好,赖氨酸态氮处理的油茶苗木叶片叶绿素含量、根系总吸收面积和根系活跃吸收面积均最高,故在试验所采用的6种氨基酸态氮中,甘氨酸、赖氨酸和丙氨酸态氮能够被油茶嫁接苗较好地吸收利用。 相似文献
8.
模拟酸雨对桉树人工林土壤养分流失的影响 总被引：2，自引：0，他引：2
以3年生桉树纯林土壤为研究对象,采用土柱淋溶法模拟酸雨沉降,配置pH值为3.0、4.0、5.6、6.0(CK)的酸雨溶液,分析桉树人工林土壤养分淋失情况。结果表明:土壤全N、硝态N经酸雨处理后含量增加,平均增加量达123.8%,其中pH 3.0处理后全N含量增加最多,为原来的2.8倍;pH 3.0与pH 5.6、pH 6.0处理后硝态N差异性极显著;铵态N含量与处理液pH值呈正相关,其中pH 3.0处理后含量最低,减少了37.1%。土壤P素含量与酸雨处理液pH值呈正相关,且处理前后差异性极显著;速效P各处理的平均流失量达54.2%,所有元素中流失量最大,流失量值最高的处理pH 3.0达77.8%,而pH 6.0处理流失量也达23.25%。土壤盐基离子含量与酸雨处理液pH值呈正相关,其中交换性Ca流失量最大,各处理平均流失量达45.2%,在pH 3.0处理下的流失量达79.8%,是所有元素和处理中流失量最大值;其次是交换性Na,交换性K受酸雨处理液影响较小。盐基离子流失量从大到小排序为:交换性Ca~(2+)交换性Na+交换性Mg~(2+)交换性K+。 相似文献
9.
在中科院长白山生态系统定位站,从地表20cm处采集土壤样品,用两种不同形式的氮肥(NO3--N,NH4 -N和NH4NO3)处理土壤样品,用盆栽试验研究了两年生红松苗木受不同浓度N源影响而产生的根际pH变化及其对根际Fe、Mn、Cu和Zn等微量元素的有效性和吸收的影响。结果表明,与对照处理相比,施加铵态氮使根际pH降低,而施加硝态氮则使根际pH增加。根际pH变化的方向与程度取决于N源及施加的浓度。根际pH的变化对根际微量元素的有效性具有显著影响,进而影响到苗木对养分的吸收利用。根际有效Fe、Mn、Cu和Zn的含量与根际pH呈负相关,而苗木叶中Fe、Mn、Cu和Zn含量与根际有效养分含量呈正相关。图5参11。 相似文献
10.
以1年生美人蕉为材料，采用5种不同施氮水平处理，对其进行生理生化指标测定。结果表明：1）不同硝态氮水平处理对提高美人蕉叶片中叶绿素a，叶绿素b含量均有影响；随着N水平的增加，在一定范围内美人蕉叶片中的叶绿素含量均呈上升趋势，其中处理B和处理C效果最明显；但是过量施用氮肥反而会抑制美人蕉的正常生长。2）不同硝态氮处理能有效增加美人蕉叶片中POD酶的活性；但浓度过高的硝态氮处理，反而会降低POD酶的活性；试验显示处理A和处理B效果最佳。 相似文献
11.
The effect of different sources and levels of N on dry matter production, nutrient uptake and ionic balance ofLarlix gmelini was studied. The results showed that the growth of the plants fertilized with ammonium was not as good as the control treatment.
The growth of the plants fertilized with ammonium nitrate did not differ significantly from that in control or nitrate treatment,
but was better than that in the ammonium treatment. Total cation concentrations in shoots varied little with N level in the
ammonium and ammonium nitrate treatments, while those in the shoot increased with N level in the nitrate treatment. The treatments
had little effect on the anion concentrations in the shoot. In the roots, the concentrations of both cations and anions changed
little except for SO4
2− and Ca2+. There existed a higher carboxylate production in the plants fertilized with nitrate. The ratio between the production of
carboxylate and the production of organic N Δ(C-A)/ΔNorg was constant with N supply in the plants receiving nitrate, but obviously declined with N supply for ammonium-fed plants.
Δ (C-A)/ΔNorg values were intermediate between those of the nitrate and the ammonium-fed plants as for the mixed N source.
Foundation item: This paper was supported by “Hundred Scientists” Project of Chinese Academy of Sciences.
Biography: CHEN Yong-liang (1969-), male, Ph. Doctor, lecture of Northeast Forestry University, Harbin 150040, Post-doctor in Institute
of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P.R. China.
Responsible editor: Song Fuman 相似文献
12.
The growth and mineral nutrition of Gmelina arborea Roxb. seedlings were investigated in response to four nitrogen-based fertilizers applied at 0, 2.5, 5.0 or 7.5 g N per plant. Nitrogen sources included NH(4)-N as ammonium sulfate, NO(3)-N as potassium nitrate, NH(4)NO(3)-N as calcium ammonium nitrate, and urea-N as urea. Seedlings fertilized with NH(4)NO(3)-N or urea-N had greater height, collar diameter, dry weight, net assimilation rate, and relative growth rate than seedlings fertilized with NH(4)-N or NO(3)-N. For all sources of nitrogen, increasing the amount of exogenously supplied N per plant promoted shoot growth more than root development, hence the root to shoot ratios of all fertilized seedlings were smaller than those of the unfertilized controls. Applications of NO(3)-N increased the nitrogen, potassium, and phosphorus concentrations of fertilized seedlings. Regardless of source, a nitrogen application of 2.5 g N per plant was apparently optimal for the growth of Gmelina seedlings on a latosolic soil. 相似文献
13.
《林业研究》2020,31(4)
Camptotheac acuminata Decne is a unique tree species in China with an important secondary metabolite,camptothecin(CPT),used in the treatment of cancer.Nitrogen(N) is an important element that affects plant growth and the accumulation of CPT.Reports on the effect of N on CPT synthesis from a genetic perspective are scarce.To explore the effects of different N sources and levels on CPT synthesis in C.acuminata,two-year-old seedlings were fertilized with different concentrations of pure ammonium sulphate,source of ammonium N(NH_4~+-N),and potassium nitrate for nitrate N(NO_3~--N).Concentrations of 2.5,5,7.5,and10 g pot~(-1) NH_4~+-N and NO_3~--N were used.The results showed that 7.5 g NH_4~+-N and NO_3~--N treatments were best for growth and fresh weight of leaves.Compared with the other treatments,the CPT content,tryptophan synthase and tryptophan decarboxylase activities,and expression of the CaTSB and CaTDCl genes under the 2.5 g NH4+-N and NO_3~--N treatments peaked significantly at 30 days.However,the expression of CaTDC2 surpassed that of the other two genes at 60 days.Therefore,compared with NH4+-N source,the NO_3~--N source was more beneficial for growth,and NO_3~--N was better for CPT yield.Consequently,leaves of C.acuminata treated with 2.5 g NO_3~--N could be harvested after 30 days to obtain maximum CPT content.CaTDC1 is more closely linked to CPT synthesis.The results of this study improved the production of CPT in C.acuminata via fertilization. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(1-4):81-93
Two coniferous forest drainage areas in central Sweden were partially fertilized with ammonium nitrate and calcium ammonium nitrate respectively, both at a dose of 150 kg N ha‐1. During the following years observations were made on stream water chemistry, invertebrates and brown trout (Salmo trutta L.). Upstream stations were used as controls. Very high concentrations of inorganic N (up to 45 mg l‐1) were recorded immediately after the fertilization. Thereafter, concentration decreased rapidly but remained elevated during the whole study period. Acidity conditions (pH, alkalinity, aluminium) were unaffected by both treatments. The only registered effect on the benthic fauna was a three‐ to five‐fold increase of drifting invertebrates during the first four‐five days after the treatment. However, this did not reduce the population density at the treated stations. No effects on population of trout were recorded. 相似文献
15.
Shoot development was studied for two consecutive years in peach trees fertilized with N either in the previous fall or in the middle of the growing season. During the first year, two additional treatments were studied: no N supply and nitrate supplied in the irrigation water throughout the growing season. The number of shoots that developed depended on nitrogen availability in the period following bud break. During shoot development, leaf emergence occurred in one, two, or three stages, which ended at about 500 to 600 degree days, 1,000 to 1,200 degree days, and 1,500 to 2,000 degree days after bloom, respectively. The proportion of shoots exhibiting a second or third developmental stage depended on nitrogen availability at the beginning of that stage. Increasing nitrogen availability during a developmental stage prolonged the stage and increased the number of leaves produced. 相似文献
16.
Effects of nitrogen source on growth and activity of nitrogen-assimilating enzymes in Douglas-fir seedlings 总被引：2，自引：0，他引：2
Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were grown for 68 days in a growth chamber in nutrient solutions with ammonium, nitrate or ammonium nitrate as the nitrogen source. Among the nitrogen sources tested, whole-seedling biomass, relative growth rate (RGR), root and shoot elongation, and number of lateral roots, were greatest in seedlings grown with ammonium. In the absence of nitrogen, plant growth and formation of lateral roots were poor. Initially, glutamine synthetase, NAD-glutamate dehydrogenase and aspartate aminotransferase activities were high in young roots and shoots, but all three enzymatic activities decreased after one month of culture. In root apices, glutamine synthetase and aspartate aminotransferase activities were higher than NAD-glutamate dehydrogenase activity. Enzymatic activities were often higher in ammonium-fed seedlings than in seedings supplied with the other forms of nitrogen. Activities of all three enzymes were significantly reduced in seedlings grown in the absence of nitrogen. The beneficial effect of ammonium is discussed on the basis of its involvement in the assimilation pathways of Douglas-fir. 相似文献
17.
Seasonal changes in above ground dry-matter, nitrogen (N), and phosphorus (P) accumulation were measured following application of N and P in autumn or spring to 1-year-old Pinus radiata (D. Don). Dry-matter production and nutrient accumulation were measured eight times over two years following fertilization.
All trees produced dry-matter throughout the year, but during the summer, fertilized trees produced more dry-matter than unfertilized trees. In contrast to dry-matter production, nutrient accumulation showed a distinctly seasonal pattern with maximum accumulation of N and P occurring in winter and spring, when rainfall and soil moisture were highest. Accumulation of N and P either slowed markedly or ceased during summer depending on fertilizer treatment. Continued dry-matter production during summer, when nutrient accumulation was low, resulted in the decline of N and P concentrations in needles, branches and stems of all trees. This indicated that nutrients required for new growth during summer were mobilized from existing foliage and wood. Fertilization increased the concentrations of N and P in foliage and wood, and these higher concentrations persisted through summer. Spring fertilization increased N accumulation to a greater extent than autumn fertilization, this effect lasting two years. The greater dry-matter production by fertilized trees during summer indicated that growth during summer was limited by nutrient supply. 相似文献
18.
Påhlsson AM 《Tree physiology》1992,10(1):93-100
Beginning in 1985, plots in a 120-year-old beech (Fagus sylvatica L.) stand in the province of Scania, southern Sweden were fertilized annually with ammonium nitrate. In August 1989, leaves from both fertilized and unfertilized trees were analyzed for mineral nutrients, soluble carbohydrates, amino acids and phenolic compounds. Leaf concentrations of total nitrogen were increased by N fertilization. Ammonium was not detected in the leaves, but NO(3) (-) was increased by up to 65% as a result of N fertilization. Nitrogen fertilization decreased foliar concentrations of P and Cu, leading to a nutrient imbalance relative to N. Of the free amino acids, glutamic acid and aspartic acid predominated and, together with glutamine and asparagine, were significantly increased by N fertilization. The concentrations of amides were 2-4 times higher in fertilized trees than in unfertilized trees. Soluble carbohydrates did not change in response to N fertilization, but total phenolic compounds decreased markedly. The reduced concentration of phenolics may explain the greater susceptibility to parasite attacks of trees exposed to N deposition and excess N. 相似文献
19.
Jack pine (Pinus banksiana Lamb.) seedlings were grown in a shaded or unshaded light regime with either NO(3) (-)- or NH(4) (+)-N as the sole N source. After three months, seedlings grown with NH(4) (+)-N were larger than seedlings grown with NO(3) (-)-N. Irradiance had a greater effect on growth of ammonium-fed seedlings than on growth of nitrate-fed seedlings.At all times from 6 to 24 h following incorporation of (15)N, soluble, insoluble, and total (15)N contents of shoots and roots were higher in ammonium-fed seedlings than in nitrate-fed seedlings. The pattern of (15)N accumulation in shoots was similar to that in roots. After 6 and 24 h of (15)N incorporation, unshaded, ammonium-fed seedlings had 8.8 and 2.8 times greater total (15)N contents, respectively, than unshaded, nitrate-fed seedlings. In response to shading, ammonium-fed seedlings increased their total uptake of (15)N per unit root weight, whereas nitrate-fed seedlings did not. No nitrate or (15)NO(3) (-) was detected in any plant tissue. Nitrate-fed plants had higher NH(4) (+), Asp, and Gln concentrations in needles and higher gamma-aminobutyric acid and Arg concentrations in stems. Accumulation of (15)N in roots was not affected by the pH of the (15)N solution or by the N source fed to the seedlings before the period of (15)N incorporation. Thus NO(3) (-) transport into roots, rather than its reduction or transport within the plant, seems to be the factor limiting the growth of jack pine supplied with NO(3) (-)-N as the sole N source. 相似文献
20.
报道细胞分裂素和硝酸铵对欧洲云杉不定芽伸长过程的影响.采用5年生的欧洲云杉1个无性系不定芽丛来研究玉米素和硝酸铵对不定芽生长的影响.试验3种诱导类型(玉米素浓度分别为6.84、13.68、20.52 μmol·L-1,激动素浓度0.69 μmol·L-1,培养4周),玉米素最高浓度处理诱导的伸长芽数量最多,在4个无生长调节剂继代培养过程中,加入了1个硝酸铵浓度逐渐增加的继代培养过程.经不含生长调节剂的低浓度的硝酸铵(2.5 mmol·L-1)培养基的继代培养后转入含有细胞分裂素的诱导培养基,下一个继代培养基补充的硝酸铵浓度分别为2.5、7.5、12.5、17.5 mmol·L-1,8周(2个继代培养)后转入含有硝酸铵浓度为2.5 mmol·L-1的培养基培养.硝酸铵浓度为7.5 mmol·L-1的处理可形成数量最多的不定芽,这对于采用不同浓度的玉米素进行诱导的处理结果是一致的,但随着硝酸铵的浓度增至12.5 mmol·L-1和17.5 mmol·L-1时则不定芽的数量减少.欧洲云杉的胚轴外植体经1次或多次诱导后,细胞分裂素(BA、激动素、玉米素、2iP)促进了不定芽的分化和发育,其中BA由于可诱导产生大量的不定芽而成为最有效的细胞分裂素.玉米素虽然诱导不定芽相对弱一些,却在BA多次诱导后可促进芽的伸长.这对获得具有形成不定芽能力并可扩繁的芽丛非常重要. 相似文献