花岗岩立地上杉木幼林施肥生长效应的初步研究

连续４年杉木幼林的施肥试验表明，花岗岩发育的黄红壤上杉木幼对磷肥的生长效应最大，单施钾肥有促进生长的作用，但单施氮肥对幼林生长我效，而磷钾、磷氮混施能明显促进林木生长。氮、磷、钾这三种肥料的效应与施肥时间有关，磷肥作基肥一次性施入优地分年施入的效果，而氮肥、钾是分别于造林后第二年和第三年施入为好。所有处理中，以（１００ｋｇＰ２Ｏ５＋１０ｋｇＫ２Ｏ）／ｈｍ＾２的处理肥效最好，（１００ｋｇＮ＋５０ｋｇ     

杉木中幼龄林计量施肥校验研究

在测定土壤平衡解吸磷和土壤钾位缓冲容量的基础上,根据林木施肥的立地养分效应模型法,结合林分的目标生物量等,提出了中等立地条件下杉木中幼龄林的施肥量,并进行了校验试验．结果表明：中等立地条件下的杉木中幼龄林,单施氮肥对胸径和蓄积量生长有显著影响,但增大氮肥用量对生长无促进作用．单施磷肥虽有利于杉木胸径生长,但对杉木蓄积量生长无显著影响,增大磷肥的施用量对蓄积量的生长无促进作用．施用钾肥对杉木生长无显著促进作用．试验区杉木中幼龄林合适的施肥量是：氮１２０ｋｇ／ｈｍ２,磷３０ｋｇ／ｈｍ２,钾１５０ｋｇ／ｈｍ２．     

鄂西南杉木中龄林垦覆施肥的生长效应

对杉木中龄林科学施肥是杉木速生丰产的1项重要抚育措施,在氮缺乏、磷钾含量较高的杉木中龄林林地上,在垦覆的条件下,施氮肥增产效果明显。1993～1997年,施尿素33kg/666.7m2,22kg/666.7m2,11kg/666.7m23处理相对于对照(垦覆不施肥),其蓄积生长量净增率为116.24%、78.08%、51.25%,单施磷肥、钾肥增产效果不明显,在同一施氮水平下,随混施磷肥或钾肥的增加,增产效果降低。     

施氮对杉木苗期生长的影响

采用田间小区试验对不同施氮水平对杉木苗生长的影响进行了研究,结果表明,随着施氮量的增加,杉木苗的苗高、地径、根长、生物量、分枝数、分枝总长、根蘖数等生长指标上均有不同程度的增加,且施N量均以150kg/hm~2时最高,但当施N量≥225kg/hm~2时又逐渐减小。     

雷竹高效栽培措施对土壤碳库的影响

采样分析了高效栽培雷竹林土壤不同形态碳含量。结果表明：竹林土壤有机碳总量（CT)接近天然马尾松林，明显高于相邻板栗林地。雷竹土壤微生物生物量碳（CMB)出现了明显下降的趋势，分别比马尾松和板栗林降低了23.12%和12.63%，连年施用化肥竹林CMB和CMB/CT下降幅度更大，近3a单用化肥竹园土壤CMB和CMB/CT比有机无机肥混施竹园降低了61.54%和58.82%，但随着覆盖年份增加，土壤CMB和CMB／CT有上升的趋势。雷竹园土壤活性碳含量（CA）以及CA／CT保持与天然马尾松林桢水平，近3a有机无机肥混施地块土壤CA和CA／CT是单施化肥地块的1.39和1.23倍，随着覆盖年份增加土壤CA也明显增加，但稳定态碳（CUA）没有明显的变化规律。雷竹园冬季覆盖物补充了土壤水溶性有机碳（CWS）的库源，使土壤CWS上升，覆盖年份从1a到5a，土壤CWS增加了1倍，土壤CWS/CT也增加了0.75倍。雷竹土壤CT与CA、CWS之间，CA与CWS之间以及CT、CA、CWS与土壤全氮、水解氮、有效磷、速效钾之间相关性均达极显著水平（P＜0.01)；而土壤CMB与CT、CA、CWS、全氮、水解氮、有效磷、速效钾之间相关性均不显著。     

一些树种苗木营养与施肥研究简介

苗木营养与施肥研究已有较长的历史,迄今已积累了相当多的资料。总结以往这个领域的研究成果,对于今后促进这一研究的深入发展有重要作用。进而为制定苗圃的科学育苗措施提供依据。一、杉木在杉木自然分布区内,土壤多为红壤,普遍存在有效磷缺乏、全氮量不足的情况,氮磷是限制杉木苗生长的主要因素,在育苗过程中施用氮磷肥成为必不可少的措施。现将杉苗肥效等方面的研究结果总结如下。1.对杉苗生长和生理指标的影响氮磷钾合理配施有利于提高苗高、地径、全苗干重以及净光合速率、暗呼吸速率、叶绿素含量、硝酸还原酶活性和根系活力。氮、磷比例失调和单施氮、磷、钾任一种肥料,各个生     

杉木林地和根际土壤酚类物质分析

为了解杉木林地和根际土壤酚类物质的含量与动态变化，同时也为了和阔叶林地及连栽林地进行比较，作者采样分析了杉木１代、２代以及檫树林地林间和根际土壤的酚类物质。结果显示：①杉木榨树两林木根际土壤总酚含量均显著高于其林间土壤，Ｒ／Ｓ植平均是１．６１和１．６７，但两种林木之间无论是根际土壤还是林间土壤总酚含量无明显不同；②杉木根际土壤游离酚含量显著高于檫树根际土，平均是檫树根际土的１１．９倍；③从１年的动     

施肥对盆栽杉木苗土壤养分含量的影响

研究施肥对1年生(1 a)与2年生(2 a)杉木苗盆栽土壤养分含量的影响.结果表明:在氮、磷营养亏缺的酸性黄红壤上,随着氮肥施用量的增加,1 a苗木盆栽土壤pH值、全钾含量下降,全氮、水解氮、水溶性钙镁含量增加,全磷、有效磷、速效钾变化不明显.由于局部尿素浓度过大直接导致幼苗受伤,影响了成活率.而2 a苗木的土壤则是全氮、水解氮、水溶性钙镁含量呈上升趋势,全钾、速效钾含量和pH值下降,有机质和全磷含量变化不明显.有效磷含量与pH值呈明显负相关,表明pH值下降导致闭蓄态磷活化,促进了2 a苗木的生长.在氮、磷营养亏缺条件下,施磷量的增加使得1 a苗木土壤全磷、有效磷、速效钾含量、pH值增加,全钾、水溶性钙镁含量则下降,有机质、水解氮没有明显变化.养分含量与生长指标的相关分析表明:施用磷肥解除了1 a苗木磷素营养亏缺,显著促进了苗木生长;而对2 a苗木,施磷肥使土壤中的全磷、有效磷增加,全钾含量下降,pH值、有机质、全氮、速效钾、水溶性钙镁没有明显变化.对养分含量与生长指标的相关分析表明:施磷肥对2 a苗木生长没有促进作用,而且使土壤营养平衡进一步失调,苗木仍处于营养亏缺状态.在氮素营养充足、磷素亏缺的营养条件下,随着氮磷复合肥施肥量的增加,2 a苗木中的全氮、全磷、水解氮、有效磷增加,速效钾含量下降.施用氮磷复合肥可促进苗木对速效钾的吸收利用,导致苗木的光合产物向叶和茎部转移.     

胡桃楸落叶松纯林与混交林中根际土壤的养分特征(英文)

与非根际土壤相比较,研究了胡桃楸落叶松纯林与混交林中根际土壤pH值、有机质及氮 、磷、钾等养分元素的特征。结果表明：各林分中,除胡桃楸纯林外,根际土壤的pH值均不 同程度低于非根际土壤;除混交林中落叶松根际土有机质含量略低于非根际土外,根际土壤 有机质含量均高于非根际土壤;根际土壤存在氮的相对累积,磷和钾在根际则具有一定的亏 缺趋势,其程度与树种相关;各林分下,氮、磷、钾在根际中均得以活化,表现为根际土壤 速效氮、磷、钾含量偏高;混交林中落叶松根际速效氮含量明显高于其纯林,而混交林中胡 桃楸根际速效磷、钾含量明显高于其纯林。     

福建省将乐县杉木人工林林地土壤养分状况

在福建省将乐国有林场,选取典型杉木人工林样地18块,对其土壤化学性状进行测定分析。结果表明:将乐杉木人工林地土壤呈酸性;土壤全氮和碱解氮含量随土层深度增加而显著递减;全磷和有效磷垂直变化不明显,且有效磷含量都小于5 mg·kg~(-1),缺磷比较严重;土壤全钾明显低于土壤速效钾的变异程度,钾素能够满足树种生长的需求。在杉木林经营过程中,合理适量的施用氮磷肥有利于林地地力的维持,特别是磷肥。     

不同浓度氮源引起的红松苗木根际pH变化及其对Fe、Mn、Cu、Zn有效性和吸收的影响(英文)

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。     

矿质肥料对柳杉苗根区土壤生化活性的影响

对柳杉１年生苗施用矿质肥料,分析苗木根区与非根区土壤养分、土壤酶活性、土壤微生物数量。结果表明：施肥显著地增加了柳杉苗根区土壤的微生物数量,细菌增幅最大,其次是真菌,施肥对非根区土的微生物数量无明显影响;施肥对柳杉苗根区土壤酶活性影响较复杂,脲酶和蔗糖酶的活性不受施肥影响,磷钾和氮磷钾处理均能显著提高蛋白酶活性,施肥还能有效地降低柳杉苗根区土壤多酚氧化酶的活性。     

经营强度对高节竹生物量的影响

对集约和粗放经营的高节竹不同器官生物量及凋落物量进行研究.结果表明:相对于粗放经营,集约经营高节竹林的1-3年生竹占比从71％增长至81％,单株叶、枝、秆生物量比粗放经营分别高66.7％、60.8％、79.4％,整株生物量比粗放经营高74.63％.集约经营高节竹林单位面积叶、枝、秆、根鞭、凋落物和总生物量分别为10.1...     

氮营养对美丽胡枝子幼苗生长和氮、磷养分吸收的影响

采用盆栽沙培法,研究分析了0、50、100、175mg/kg4种不同氮营养供给水平对美丽胡枝子(Lespedeza formosa)幼苗生长和其体内氮、磷二种养分浓度变化的影响。结果表明,施加0～100mg/kg氮对幼苗株高、地上和地下部分的生长都有促进作用,但超过100mg/kg氮时,过量供氮对幼苗的生长产生抑制作用;氮供给不足时,幼苗表现出将更多的生物量分配到根系,根冠比大;幼苗根和茎叶中的氮浓度随供氮水平的增加而增加。在供氮为0～50mg/kg时,幼苗根和茎叶中的磷浓度随氮浓度的增加稍有下降,当供氮浓度在50～100mg/kg时,根和茎叶中磷浓度随氮浓度的增加而升高,当氮浓度超过100mg/kg时,其根和茎叶中的磷浓度随氮浓度的增加而呈下降趋势。     

不同浓度氨源引起的红松苗木根际pH变化及其对Fe、Mn、Cu、Zn有效性和吸收的影响

Dark brown forest soil was collected from the upper 20 cm soil layer in Changbai Mountain Research Station of Ecosystem, Chinese Academy of Sciences. The soil was amended with two different forms of nitrogen fertilizers: NO₃ as Ca(NO₃)₂, NH₄ ⁺ as NH₄Cl at the concentrations of 50, 100, 200 and 400 mg kg⁻¹respectively. The experiment was carried out with 2-yr-oldPinus koraiensis seedlings in pot. The pH change of rhizosphere soil and the contents of available Fe, Mn, Cu, and Zn in soil and leaves were analyzed. The result indicated that the addition of NH₄-N decreased the rhizosphere pH value, while the addition of NO₃-N increased the rhizosphere pH value in contrast with the control treatment. The direction and extent of the pH change mainly depended on N source and its concentrations applied. The rhizosphere pH change had a remarkable influence on the availability of the micronutrients in the rhizosphere, and thereafter affected the nutrient uptake by the seedlings. The contents of available mineral nutrients had a negative correlation with the pH value in the rhizosphere soil. The contents of available mineral nutrients in leaves were positively correlated to the levels of the available nutrients in the rhizosphere soils. Foundation item: This paper was supported by National Natural Science Foundation of China (Grant No. 30170167). 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 Funan     

Fine-root rhizosphere and morphological adaptations to site conditions in interaction with tree mineral nutrition in young silver birch (<Emphasis Type="Italic">Betula pendula</Emphasis> Roth.) stands

Limited nutrient acquisition from soil is a key process limiting productivity in boreal forest. We investigated short-root morphological adaptations and rhizosphere effect in relation to site conditions in interaction with tree mineral nutrition. We studied seven young (8- to 14-year-old) silver birch (Betula pendula Roth.) stands on abandoned agricultural land in Estonia. Soil pH varied from 3.8 to 7.0, and soil N % from 0.07 to 0.26%. Tree nutrient (NPK) status was expressed by leaf nutrient concentrations. Leaf N correlated negatively with short-root specific length and area. Summed activity (SA) and metabolic diversity of bacteria (by BIOLOG Ecoplate™), bacterial community diversity (by DGGE) and pH_KCl were determined for rhizosphere (R) and bulk soil (S) to reveal the extent of the rhizosphere effect. Bacterial activity in rhizosphere was 1.4–4.7 times higher than in bulk soil. Ratio SA_R/SA_S indicating root support to the rhizosphere bacterial communities decreased with increasing bulk soil pH; however, when bulk soil pH was ≥5, the decrease in SA_R/SA_S was insignificant, i.e. the rhizosphere effect stayed at a stable level. Diversity of bacterial community was 6% higher in bulk soil than in rhizosphere. Rhizosphere acidification occurred in studied stands when bulk soil pH_KCl ≥ 5. Short-root N % correlated positively with SA_R/SA_S. We concluded that tree N-nutritional status was related to short-root morphological parameters but not to studied microbiological characteristics in the soil of young silver birch stands.     

腐殖酸与无机肥配施对I-107欧美杨养分和土壤肥力的影响

腐殖酸是一种廉价无污染的有效肥料基质,广泛存在于褐煤、风化煤、泥炭和草炭中。腐殖酸具有多种活性基团,有利于土壤团粒结构形成,改善土壤结构,提高土壤保墒能力,还可增强土壤阳离子交换能力,调节土壤pH值,提高土壤养分有效性(武丽     

Effects of different soil treatments on growth and net nitrogen uptake of newly planted Picea abies (L.) Karst. seedlings

Five soil treatments in a 4-year-old clearcut in southern Sweden affected biomass increase and net nitrogen uptake by planted Norway spruce (Picea abies (L.) Karst.) seedlings through their on net mineralisation and root growth. The patch soil treatments studied were: (i) soil inversion in an old clearcut; (ii) mineral soil from the clearcut remaining, (iii) mineral soil from the clearcut with fertiliser application during the first season; (iv) mineral soil from a nearby uncut forest replacing the clearcut mineral soil; and (v) an untreated control. Growth increased in seedlings in treatments (i) and (iii), but growth in soil treatments with humus removal was not better than that of seedlings in untreated soil. High N uptake early in the first growing season resulted in increased growth during this season in contrast to late N uptake that resulted in a high N concentration in the seedlings after the first growing season. This in turn led to a high growth rate during the next growing season. Generally, both root growth and net N mineralisation were positively correlated to N uptake in the soil treatments. Therefore, a combination of low net N mineralisation and poor root growth as a result of high soil density appears to explain the low N uptake in seedlings in undisturbed soil. The importance of competition with field vegetation for N and water was not clear. Net mineralisation was larger in soil treatments where the humus layer was retained than where it was removed. Net N mineralisation in soil from old clearcuts was the same as in soil from fresh clearcuts.     

Organic fertilization leads to increased peach root production and lifespan

We evaluated the effects of mineral and organic fertilizers on peach root dynamics in the growing season from 2003 to 2006 in a nectarine (Prunus persica L.) orchard, planted in 2001 and located in the Po valley, northeastern Italy. Very few studies have conducted long-term investigations of root dynamics of fruit crops. Our main objective was to determine whether organic fertilizers affect root dynamics differently than mineral fertilizers. The experiment was a completely randomized block design with four replicates of three treatments: unfertilized, mineral fertilized and composted with municipal waste. Mineral fertilizers included P (100?kg?ha(-1)?year(-1)) and K (200?kg?ha(-1)?year(-1)) applied only at planting and N (70-130?kg?ha(-1)?year(-1)) split into two applications, one at 40 days after full bloom (60%) and the other in September (40%) each year. The compost fertilization represented a yearly rate of 10 metric tons (t) dry weight?ha(-1), which approximates (in kg?ha(-1)?year(-1)) 240 N, 100 P and 200 K, split similarly to that described for the mineral fertilization of N. Both root growth and survival were evaluated at 20-day intervals during the growing season by the minirhizotron technique. Compost increased the production of new roots compared with the other treatments (P?相似文献   

盐分和水分胁迫对落羽杉幼苗的生长量及营养元素含量的影响

采用温室盆栽试验方法 ,研究了不同土壤水分下盐胁迫对 1年生落羽杉实生苗的生长及营养吸收的影响。试验共 12种处理 ,3种水分水平 (W1 ,淹水 ;W2 、W3,土壤含水量分别为田间持水量的 75 %和 2 5 % ) ,每种水分下设 4种盐分处理 (NaCl含量为土壤干重的 0、0 15 %、0 3%和 0 4 5 % ) ,处理时间为 130d。结果表明 :土壤盐分胁迫下落羽杉幼苗的生长及对营养的吸收发生了显著的变化 ,这种变化又因土壤含水量的不同而不同。落羽杉相对高生长、相对地径生长和生物量增量随着土壤盐分浓度的增加和土壤水分含量的减少而减少。在淹水条件下 ,随着土壤盐分浓度的增加 ,落羽杉幼苗根、茎、叶中全N、全P、全Na,以及叶片中的全Ca、全Fe的含量均随着升高 ,而根、茎中的全Fe、全Ca、全Mg含量差异较小。在W2 水分条件下 ,各种盐分处理都在不同程度上增加了根、茎、叶中全N、全Na、全Ca和全Fe含量 ,茎和叶中全P、全K和全Mg含量 ,而根系中的全P、全K和全Mg含量在盐分浓度较高时有所下降。在W3水分条件下 ,各种土壤盐分不同程度地增加了叶片全N、全P和全K含量 ,茎和叶中全Mg和全Ca含量 ,以及根、茎、叶中全Na含量 ,而茎和根中全N、全P和全K含量 ,根、茎和叶中全Fe含量均随着土壤盐分浓度的增加而下降。